ETH Price: $2,049.62 (+10.98%)

Transaction Decoder

Block:
24393872 at Feb-05-2026 11:21:11 PM +UTC
Transaction Fee:
0.000168461088675432 ETH $0.35
Gas Used:
132,258 Gas / 1.273730804 Gwei

Emitted Events:

24 FiatTokenProxy.0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef( 0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef, 0x000000000000000000000000f7fd0860922bd3352e2dbaf725a182b74bf7a2e1, 0x00000000000000000000000051c72848c68a965f66fa7a88855f9f7784502a7f, 000000000000000000000000000000000000000000000000000000000d568729 )
25 PromptToken.Transfer( from=[Receiver] 0x51c72848c68a965f66fa7a88855f9f7784502a7f, to=UniswapV3Pool, value=4581336613352615968768 )
26 UniswapV3Pool.Swap( sender=[Receiver] 0x51c72848c68a965f66fa7a88855f9f7784502a7f, recipient=[Receiver] 0x51c72848c68a965f66fa7a88855f9f7784502a7f, amount0=4581336613352615968768, amount1=-223774505, sqrtPriceX96=17524814298339837672086, liquidity=762850691250636520, tick=-306500 )

Account State Difference:

  Address   Before After State Difference Code
0x28d38dF6...a82041544
(Titan Builder)
15.144609336561307271 Eth15.144681602051984564 Eth0.000072265490677293
0x4b9fcc41...e8752D4DA
1.346380734074959838 Eth
Nonce: 4219
1.346212272986284406 Eth
Nonce: 4220
0.000168461088675432
0x51C72848...784502a7F 144.575731070098233202 Eth144.575658804607555909 Eth0.000072265490677293
0xA0b86991...E3606eB48
0xf7Fd0860...74bf7A2e1
(Uniswap V3: PROMPT-USDC)

Execution Trace

MEV Bot: 0x51C…a7F.771d503f( )
  • UniswapV3Pool.swap( recipient=0x51C72848c68a965f66FA7a88855F9f7784502a7F, zeroForOne=True, amountSpecified=4581336613352615968768, sqrtPriceLimitX96=4295128740, data=0x28D38DF637DB75533BD3F71426F3410A82041544 ) => ( amount0=4581336613352615968768, amount1=-223774505 )
    • FiatTokenProxy.a9059cbb( )
      • FiatTokenV2_2.transfer( to=0x51C72848c68a965f66FA7a88855F9f7784502a7F, value=223774505 ) => ( True )
      • PromptToken.balanceOf( account=0xf7Fd0860922bD3352E2DBAf725A182b74bf7A2e1 ) => ( 5598675389170816337893919 )
      • MEV Bot: 0x51C…a7F.fa461e33( )
        • PromptToken.transfer( to=0xf7Fd0860922bD3352E2DBAf725A182b74bf7A2e1, amount=4581336613352615968768 ) => ( True )
        • PromptToken.balanceOf( account=0xf7Fd0860922bD3352E2DBAf725A182b74bf7A2e1 ) => ( 5603256725784168953862687 )
        • ETH 0.000072265490677293 Titan Builder.CALL( )
          File 1 of 4: FiatTokenProxy
          pragma solidity ^0.4.24;
          
          // File: zos-lib/contracts/upgradeability/Proxy.sol
          
          /**
           * @title Proxy
           * @dev Implements delegation of calls to other contracts, with proper
           * forwarding of return values and bubbling of failures.
           * It defines a fallback function that delegates all calls to the address
           * returned by the abstract _implementation() internal function.
           */
          contract Proxy {
            /**
             * @dev Fallback function.
             * Implemented entirely in `_fallback`.
             */
            function () payable external {
              _fallback();
            }
          
            /**
             * @return The Address of the implementation.
             */
            function _implementation() internal view returns (address);
          
            /**
             * @dev Delegates execution to an implementation contract.
             * This is a low level function that doesn't return to its internal call site.
             * It will return to the external caller whatever the implementation returns.
             * @param implementation Address to delegate.
             */
            function _delegate(address implementation) internal {
              assembly {
                // Copy msg.data. We take full control of memory in this inline assembly
                // block because it will not return to Solidity code. We overwrite the
                // Solidity scratch pad at memory position 0.
                calldatacopy(0, 0, calldatasize)
          
                // Call the implementation.
                // out and outsize are 0 because we don't know the size yet.
                let result := delegatecall(gas, implementation, 0, calldatasize, 0, 0)
          
                // Copy the returned data.
                returndatacopy(0, 0, returndatasize)
          
                switch result
                // delegatecall returns 0 on error.
                case 0 { revert(0, returndatasize) }
                default { return(0, returndatasize) }
              }
            }
          
            /**
             * @dev Function that is run as the first thing in the fallback function.
             * Can be redefined in derived contracts to add functionality.
             * Redefinitions must call super._willFallback().
             */
            function _willFallback() internal {
            }
          
            /**
             * @dev fallback implementation.
             * Extracted to enable manual triggering.
             */
            function _fallback() internal {
              _willFallback();
              _delegate(_implementation());
            }
          }
          
          // File: openzeppelin-solidity/contracts/AddressUtils.sol
          
          /**
           * Utility library of inline functions on addresses
           */
          library AddressUtils {
          
            /**
             * Returns whether the target address is a contract
             * @dev This function will return false if invoked during the constructor of a contract,
             * as the code is not actually created until after the constructor finishes.
             * @param addr address to check
             * @return whether the target address is a contract
             */
            function isContract(address addr) internal view returns (bool) {
              uint256 size;
              // XXX Currently there is no better way to check if there is a contract in an address
              // than to check the size of the code at that address.
              // See https://ethereum.stackexchange.com/a/14016/36603
              // for more details about how this works.
              // TODO Check this again before the Serenity release, because all addresses will be
              // contracts then.
              // solium-disable-next-line security/no-inline-assembly
              assembly { size := extcodesize(addr) }
              return size > 0;
            }
          
          }
          
          // File: zos-lib/contracts/upgradeability/UpgradeabilityProxy.sol
          
          /**
           * @title UpgradeabilityProxy
           * @dev This contract implements a proxy that allows to change the
           * implementation address to which it will delegate.
           * Such a change is called an implementation upgrade.
           */
          contract UpgradeabilityProxy is Proxy {
            /**
             * @dev Emitted when the implementation is upgraded.
             * @param implementation Address of the new implementation.
             */
            event Upgraded(address implementation);
          
            /**
             * @dev Storage slot with the address of the current implementation.
             * This is the keccak-256 hash of "org.zeppelinos.proxy.implementation", and is
             * validated in the constructor.
             */
            bytes32 private constant IMPLEMENTATION_SLOT = 0x7050c9e0f4ca769c69bd3a8ef740bc37934f8e2c036e5a723fd8ee048ed3f8c3;
          
            /**
             * @dev Contract constructor.
             * @param _implementation Address of the initial implementation.
             */
            constructor(address _implementation) public {
              assert(IMPLEMENTATION_SLOT == keccak256("org.zeppelinos.proxy.implementation"));
          
              _setImplementation(_implementation);
            }
          
            /**
             * @dev Returns the current implementation.
             * @return Address of the current implementation
             */
            function _implementation() internal view returns (address impl) {
              bytes32 slot = IMPLEMENTATION_SLOT;
              assembly {
                impl := sload(slot)
              }
            }
          
            /**
             * @dev Upgrades the proxy to a new implementation.
             * @param newImplementation Address of the new implementation.
             */
            function _upgradeTo(address newImplementation) internal {
              _setImplementation(newImplementation);
              emit Upgraded(newImplementation);
            }
          
            /**
             * @dev Sets the implementation address of the proxy.
             * @param newImplementation Address of the new implementation.
             */
            function _setImplementation(address newImplementation) private {
              require(AddressUtils.isContract(newImplementation), "Cannot set a proxy implementation to a non-contract address");
          
              bytes32 slot = IMPLEMENTATION_SLOT;
          
              assembly {
                sstore(slot, newImplementation)
              }
            }
          }
          
          // File: zos-lib/contracts/upgradeability/AdminUpgradeabilityProxy.sol
          
          /**
           * @title AdminUpgradeabilityProxy
           * @dev This contract combines an upgradeability proxy with an authorization
           * mechanism for administrative tasks.
           * All external functions in this contract must be guarded by the
           * `ifAdmin` modifier. See ethereum/solidity#3864 for a Solidity
           * feature proposal that would enable this to be done automatically.
           */
          contract AdminUpgradeabilityProxy is UpgradeabilityProxy {
            /**
             * @dev Emitted when the administration has been transferred.
             * @param previousAdmin Address of the previous admin.
             * @param newAdmin Address of the new admin.
             */
            event AdminChanged(address previousAdmin, address newAdmin);
          
            /**
             * @dev Storage slot with the admin of the contract.
             * This is the keccak-256 hash of "org.zeppelinos.proxy.admin", and is
             * validated in the constructor.
             */
            bytes32 private constant ADMIN_SLOT = 0x10d6a54a4754c8869d6886b5f5d7fbfa5b4522237ea5c60d11bc4e7a1ff9390b;
          
            /**
             * @dev Modifier to check whether the `msg.sender` is the admin.
             * If it is, it will run the function. Otherwise, it will delegate the call
             * to the implementation.
             */
            modifier ifAdmin() {
              if (msg.sender == _admin()) {
                _;
              } else {
                _fallback();
              }
            }
          
            /**
             * Contract constructor.
             * It sets the `msg.sender` as the proxy administrator.
             * @param _implementation address of the initial implementation.
             */
            constructor(address _implementation) UpgradeabilityProxy(_implementation) public {
              assert(ADMIN_SLOT == keccak256("org.zeppelinos.proxy.admin"));
          
              _setAdmin(msg.sender);
            }
          
            /**
             * @return The address of the proxy admin.
             */
            function admin() external view ifAdmin returns (address) {
              return _admin();
            }
          
            /**
             * @return The address of the implementation.
             */
            function implementation() external view ifAdmin returns (address) {
              return _implementation();
            }
          
            /**
             * @dev Changes the admin of the proxy.
             * Only the current admin can call this function.
             * @param newAdmin Address to transfer proxy administration to.
             */
            function changeAdmin(address newAdmin) external ifAdmin {
              require(newAdmin != address(0), "Cannot change the admin of a proxy to the zero address");
              emit AdminChanged(_admin(), newAdmin);
              _setAdmin(newAdmin);
            }
          
            /**
             * @dev Upgrade the backing implementation of the proxy.
             * Only the admin can call this function.
             * @param newImplementation Address of the new implementation.
             */
            function upgradeTo(address newImplementation) external ifAdmin {
              _upgradeTo(newImplementation);
            }
          
            /**
             * @dev Upgrade the backing implementation of the proxy and call a function
             * on the new implementation.
             * This is useful to initialize the proxied contract.
             * @param newImplementation Address of the new implementation.
             * @param data Data to send as msg.data in the low level call.
             * It should include the signature and the parameters of the function to be
             * called, as described in
             * https://solidity.readthedocs.io/en/develop/abi-spec.html#function-selector-and-argument-encoding.
             */
            function upgradeToAndCall(address newImplementation, bytes data) payable external ifAdmin {
              _upgradeTo(newImplementation);
              require(address(this).call.value(msg.value)(data));
            }
          
            /**
             * @return The admin slot.
             */
            function _admin() internal view returns (address adm) {
              bytes32 slot = ADMIN_SLOT;
              assembly {
                adm := sload(slot)
              }
            }
          
            /**
             * @dev Sets the address of the proxy admin.
             * @param newAdmin Address of the new proxy admin.
             */
            function _setAdmin(address newAdmin) internal {
              bytes32 slot = ADMIN_SLOT;
          
              assembly {
                sstore(slot, newAdmin)
              }
            }
          
            /**
             * @dev Only fall back when the sender is not the admin.
             */
            function _willFallback() internal {
              require(msg.sender != _admin(), "Cannot call fallback function from the proxy admin");
              super._willFallback();
            }
          }
          
          // File: contracts/FiatTokenProxy.sol
          
          /**
          * Copyright CENTRE SECZ 2018
          *
          * Permission is hereby granted, free of charge, to any person obtaining a copy 
          * of this software and associated documentation files (the "Software"), to deal 
          * in the Software without restriction, including without limitation the rights 
          * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 
          * copies of the Software, and to permit persons to whom the Software is furnished to 
          * do so, subject to the following conditions:
          *
          * The above copyright notice and this permission notice shall be included in all 
          * copies or substantial portions of the Software.
          *
          * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 
          * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 
          * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 
          * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
          * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 
          * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
          */
          
          pragma solidity ^0.4.24;
          
          
          /**
           * @title FiatTokenProxy
           * @dev This contract proxies FiatToken calls and enables FiatToken upgrades
          */ 
          contract FiatTokenProxy is AdminUpgradeabilityProxy {
              constructor(address _implementation) public AdminUpgradeabilityProxy(_implementation) {
              }
          }

          File 2 of 4: UniswapV3Pool
          // SPDX-License-Identifier: BUSL-1.1
          pragma solidity =0.7.6;
          import './interfaces/IUniswapV3Pool.sol';
          import './NoDelegateCall.sol';
          import './libraries/LowGasSafeMath.sol';
          import './libraries/SafeCast.sol';
          import './libraries/Tick.sol';
          import './libraries/TickBitmap.sol';
          import './libraries/Position.sol';
          import './libraries/Oracle.sol';
          import './libraries/FullMath.sol';
          import './libraries/FixedPoint128.sol';
          import './libraries/TransferHelper.sol';
          import './libraries/TickMath.sol';
          import './libraries/LiquidityMath.sol';
          import './libraries/SqrtPriceMath.sol';
          import './libraries/SwapMath.sol';
          import './interfaces/IUniswapV3PoolDeployer.sol';
          import './interfaces/IUniswapV3Factory.sol';
          import './interfaces/IERC20Minimal.sol';
          import './interfaces/callback/IUniswapV3MintCallback.sol';
          import './interfaces/callback/IUniswapV3SwapCallback.sol';
          import './interfaces/callback/IUniswapV3FlashCallback.sol';
          contract UniswapV3Pool is IUniswapV3Pool, NoDelegateCall {
              using LowGasSafeMath for uint256;
              using LowGasSafeMath for int256;
              using SafeCast for uint256;
              using SafeCast for int256;
              using Tick for mapping(int24 => Tick.Info);
              using TickBitmap for mapping(int16 => uint256);
              using Position for mapping(bytes32 => Position.Info);
              using Position for Position.Info;
              using Oracle for Oracle.Observation[65535];
              /// @inheritdoc IUniswapV3PoolImmutables
              address public immutable override factory;
              /// @inheritdoc IUniswapV3PoolImmutables
              address public immutable override token0;
              /// @inheritdoc IUniswapV3PoolImmutables
              address public immutable override token1;
              /// @inheritdoc IUniswapV3PoolImmutables
              uint24 public immutable override fee;
              /// @inheritdoc IUniswapV3PoolImmutables
              int24 public immutable override tickSpacing;
              /// @inheritdoc IUniswapV3PoolImmutables
              uint128 public immutable override maxLiquidityPerTick;
              struct Slot0 {
                  // the current price
                  uint160 sqrtPriceX96;
                  // the current tick
                  int24 tick;
                  // the most-recently updated index of the observations array
                  uint16 observationIndex;
                  // the current maximum number of observations that are being stored
                  uint16 observationCardinality;
                  // the next maximum number of observations to store, triggered in observations.write
                  uint16 observationCardinalityNext;
                  // the current protocol fee as a percentage of the swap fee taken on withdrawal
                  // represented as an integer denominator (1/x)%
                  uint8 feeProtocol;
                  // whether the pool is locked
                  bool unlocked;
              }
              /// @inheritdoc IUniswapV3PoolState
              Slot0 public override slot0;
              /// @inheritdoc IUniswapV3PoolState
              uint256 public override feeGrowthGlobal0X128;
              /// @inheritdoc IUniswapV3PoolState
              uint256 public override feeGrowthGlobal1X128;
              // accumulated protocol fees in token0/token1 units
              struct ProtocolFees {
                  uint128 token0;
                  uint128 token1;
              }
              /// @inheritdoc IUniswapV3PoolState
              ProtocolFees public override protocolFees;
              /// @inheritdoc IUniswapV3PoolState
              uint128 public override liquidity;
              /// @inheritdoc IUniswapV3PoolState
              mapping(int24 => Tick.Info) public override ticks;
              /// @inheritdoc IUniswapV3PoolState
              mapping(int16 => uint256) public override tickBitmap;
              /// @inheritdoc IUniswapV3PoolState
              mapping(bytes32 => Position.Info) public override positions;
              /// @inheritdoc IUniswapV3PoolState
              Oracle.Observation[65535] public override observations;
              /// @dev Mutually exclusive reentrancy protection into the pool to/from a method. This method also prevents entrance
              /// to a function before the pool is initialized. The reentrancy guard is required throughout the contract because
              /// we use balance checks to determine the payment status of interactions such as mint, swap and flash.
              modifier lock() {
                  require(slot0.unlocked, 'LOK');
                  slot0.unlocked = false;
                  _;
                  slot0.unlocked = true;
              }
              /// @dev Prevents calling a function from anyone except the address returned by IUniswapV3Factory#owner()
              modifier onlyFactoryOwner() {
                  require(msg.sender == IUniswapV3Factory(factory).owner());
                  _;
              }
              constructor() {
                  int24 _tickSpacing;
                  (factory, token0, token1, fee, _tickSpacing) = IUniswapV3PoolDeployer(msg.sender).parameters();
                  tickSpacing = _tickSpacing;
                  maxLiquidityPerTick = Tick.tickSpacingToMaxLiquidityPerTick(_tickSpacing);
              }
              /// @dev Common checks for valid tick inputs.
              function checkTicks(int24 tickLower, int24 tickUpper) private pure {
                  require(tickLower < tickUpper, 'TLU');
                  require(tickLower >= TickMath.MIN_TICK, 'TLM');
                  require(tickUpper <= TickMath.MAX_TICK, 'TUM');
              }
              /// @dev Returns the block timestamp truncated to 32 bits, i.e. mod 2**32. This method is overridden in tests.
              function _blockTimestamp() internal view virtual returns (uint32) {
                  return uint32(block.timestamp); // truncation is desired
              }
              /// @dev Get the pool's balance of token0
              /// @dev This function is gas optimized to avoid a redundant extcodesize check in addition to the returndatasize
              /// check
              function balance0() private view returns (uint256) {
                  (bool success, bytes memory data) =
                      token0.staticcall(abi.encodeWithSelector(IERC20Minimal.balanceOf.selector, address(this)));
                  require(success && data.length >= 32);
                  return abi.decode(data, (uint256));
              }
              /// @dev Get the pool's balance of token1
              /// @dev This function is gas optimized to avoid a redundant extcodesize check in addition to the returndatasize
              /// check
              function balance1() private view returns (uint256) {
                  (bool success, bytes memory data) =
                      token1.staticcall(abi.encodeWithSelector(IERC20Minimal.balanceOf.selector, address(this)));
                  require(success && data.length >= 32);
                  return abi.decode(data, (uint256));
              }
              /// @inheritdoc IUniswapV3PoolDerivedState
              function snapshotCumulativesInside(int24 tickLower, int24 tickUpper)
                  external
                  view
                  override
                  noDelegateCall
                  returns (
                      int56 tickCumulativeInside,
                      uint160 secondsPerLiquidityInsideX128,
                      uint32 secondsInside
                  )
              {
                  checkTicks(tickLower, tickUpper);
                  int56 tickCumulativeLower;
                  int56 tickCumulativeUpper;
                  uint160 secondsPerLiquidityOutsideLowerX128;
                  uint160 secondsPerLiquidityOutsideUpperX128;
                  uint32 secondsOutsideLower;
                  uint32 secondsOutsideUpper;
                  {
                      Tick.Info storage lower = ticks[tickLower];
                      Tick.Info storage upper = ticks[tickUpper];
                      bool initializedLower;
                      (tickCumulativeLower, secondsPerLiquidityOutsideLowerX128, secondsOutsideLower, initializedLower) = (
                          lower.tickCumulativeOutside,
                          lower.secondsPerLiquidityOutsideX128,
                          lower.secondsOutside,
                          lower.initialized
                      );
                      require(initializedLower);
                      bool initializedUpper;
                      (tickCumulativeUpper, secondsPerLiquidityOutsideUpperX128, secondsOutsideUpper, initializedUpper) = (
                          upper.tickCumulativeOutside,
                          upper.secondsPerLiquidityOutsideX128,
                          upper.secondsOutside,
                          upper.initialized
                      );
                      require(initializedUpper);
                  }
                  Slot0 memory _slot0 = slot0;
                  if (_slot0.tick < tickLower) {
                      return (
                          tickCumulativeLower - tickCumulativeUpper,
                          secondsPerLiquidityOutsideLowerX128 - secondsPerLiquidityOutsideUpperX128,
                          secondsOutsideLower - secondsOutsideUpper
                      );
                  } else if (_slot0.tick < tickUpper) {
                      uint32 time = _blockTimestamp();
                      (int56 tickCumulative, uint160 secondsPerLiquidityCumulativeX128) =
                          observations.observeSingle(
                              time,
                              0,
                              _slot0.tick,
                              _slot0.observationIndex,
                              liquidity,
                              _slot0.observationCardinality
                          );
                      return (
                          tickCumulative - tickCumulativeLower - tickCumulativeUpper,
                          secondsPerLiquidityCumulativeX128 -
                              secondsPerLiquidityOutsideLowerX128 -
                              secondsPerLiquidityOutsideUpperX128,
                          time - secondsOutsideLower - secondsOutsideUpper
                      );
                  } else {
                      return (
                          tickCumulativeUpper - tickCumulativeLower,
                          secondsPerLiquidityOutsideUpperX128 - secondsPerLiquidityOutsideLowerX128,
                          secondsOutsideUpper - secondsOutsideLower
                      );
                  }
              }
              /// @inheritdoc IUniswapV3PoolDerivedState
              function observe(uint32[] calldata secondsAgos)
                  external
                  view
                  override
                  noDelegateCall
                  returns (int56[] memory tickCumulatives, uint160[] memory secondsPerLiquidityCumulativeX128s)
              {
                  return
                      observations.observe(
                          _blockTimestamp(),
                          secondsAgos,
                          slot0.tick,
                          slot0.observationIndex,
                          liquidity,
                          slot0.observationCardinality
                      );
              }
              /// @inheritdoc IUniswapV3PoolActions
              function increaseObservationCardinalityNext(uint16 observationCardinalityNext)
                  external
                  override
                  lock
                  noDelegateCall
              {
                  uint16 observationCardinalityNextOld = slot0.observationCardinalityNext; // for the event
                  uint16 observationCardinalityNextNew =
                      observations.grow(observationCardinalityNextOld, observationCardinalityNext);
                  slot0.observationCardinalityNext = observationCardinalityNextNew;
                  if (observationCardinalityNextOld != observationCardinalityNextNew)
                      emit IncreaseObservationCardinalityNext(observationCardinalityNextOld, observationCardinalityNextNew);
              }
              /// @inheritdoc IUniswapV3PoolActions
              /// @dev not locked because it initializes unlocked
              function initialize(uint160 sqrtPriceX96) external override {
                  require(slot0.sqrtPriceX96 == 0, 'AI');
                  int24 tick = TickMath.getTickAtSqrtRatio(sqrtPriceX96);
                  (uint16 cardinality, uint16 cardinalityNext) = observations.initialize(_blockTimestamp());
                  slot0 = Slot0({
                      sqrtPriceX96: sqrtPriceX96,
                      tick: tick,
                      observationIndex: 0,
                      observationCardinality: cardinality,
                      observationCardinalityNext: cardinalityNext,
                      feeProtocol: 0,
                      unlocked: true
                  });
                  emit Initialize(sqrtPriceX96, tick);
              }
              struct ModifyPositionParams {
                  // the address that owns the position
                  address owner;
                  // the lower and upper tick of the position
                  int24 tickLower;
                  int24 tickUpper;
                  // any change in liquidity
                  int128 liquidityDelta;
              }
              /// @dev Effect some changes to a position
              /// @param params the position details and the change to the position's liquidity to effect
              /// @return position a storage pointer referencing the position with the given owner and tick range
              /// @return amount0 the amount of token0 owed to the pool, negative if the pool should pay the recipient
              /// @return amount1 the amount of token1 owed to the pool, negative if the pool should pay the recipient
              function _modifyPosition(ModifyPositionParams memory params)
                  private
                  noDelegateCall
                  returns (
                      Position.Info storage position,
                      int256 amount0,
                      int256 amount1
                  )
              {
                  checkTicks(params.tickLower, params.tickUpper);
                  Slot0 memory _slot0 = slot0; // SLOAD for gas optimization
                  position = _updatePosition(
                      params.owner,
                      params.tickLower,
                      params.tickUpper,
                      params.liquidityDelta,
                      _slot0.tick
                  );
                  if (params.liquidityDelta != 0) {
                      if (_slot0.tick < params.tickLower) {
                          // current tick is below the passed range; liquidity can only become in range by crossing from left to
                          // right, when we'll need _more_ token0 (it's becoming more valuable) so user must provide it
                          amount0 = SqrtPriceMath.getAmount0Delta(
                              TickMath.getSqrtRatioAtTick(params.tickLower),
                              TickMath.getSqrtRatioAtTick(params.tickUpper),
                              params.liquidityDelta
                          );
                      } else if (_slot0.tick < params.tickUpper) {
                          // current tick is inside the passed range
                          uint128 liquidityBefore = liquidity; // SLOAD for gas optimization
                          // write an oracle entry
                          (slot0.observationIndex, slot0.observationCardinality) = observations.write(
                              _slot0.observationIndex,
                              _blockTimestamp(),
                              _slot0.tick,
                              liquidityBefore,
                              _slot0.observationCardinality,
                              _slot0.observationCardinalityNext
                          );
                          amount0 = SqrtPriceMath.getAmount0Delta(
                              _slot0.sqrtPriceX96,
                              TickMath.getSqrtRatioAtTick(params.tickUpper),
                              params.liquidityDelta
                          );
                          amount1 = SqrtPriceMath.getAmount1Delta(
                              TickMath.getSqrtRatioAtTick(params.tickLower),
                              _slot0.sqrtPriceX96,
                              params.liquidityDelta
                          );
                          liquidity = LiquidityMath.addDelta(liquidityBefore, params.liquidityDelta);
                      } else {
                          // current tick is above the passed range; liquidity can only become in range by crossing from right to
                          // left, when we'll need _more_ token1 (it's becoming more valuable) so user must provide it
                          amount1 = SqrtPriceMath.getAmount1Delta(
                              TickMath.getSqrtRatioAtTick(params.tickLower),
                              TickMath.getSqrtRatioAtTick(params.tickUpper),
                              params.liquidityDelta
                          );
                      }
                  }
              }
              /// @dev Gets and updates a position with the given liquidity delta
              /// @param owner the owner of the position
              /// @param tickLower the lower tick of the position's tick range
              /// @param tickUpper the upper tick of the position's tick range
              /// @param tick the current tick, passed to avoid sloads
              function _updatePosition(
                  address owner,
                  int24 tickLower,
                  int24 tickUpper,
                  int128 liquidityDelta,
                  int24 tick
              ) private returns (Position.Info storage position) {
                  position = positions.get(owner, tickLower, tickUpper);
                  uint256 _feeGrowthGlobal0X128 = feeGrowthGlobal0X128; // SLOAD for gas optimization
                  uint256 _feeGrowthGlobal1X128 = feeGrowthGlobal1X128; // SLOAD for gas optimization
                  // if we need to update the ticks, do it
                  bool flippedLower;
                  bool flippedUpper;
                  if (liquidityDelta != 0) {
                      uint32 time = _blockTimestamp();
                      (int56 tickCumulative, uint160 secondsPerLiquidityCumulativeX128) =
                          observations.observeSingle(
                              time,
                              0,
                              slot0.tick,
                              slot0.observationIndex,
                              liquidity,
                              slot0.observationCardinality
                          );
                      flippedLower = ticks.update(
                          tickLower,
                          tick,
                          liquidityDelta,
                          _feeGrowthGlobal0X128,
                          _feeGrowthGlobal1X128,
                          secondsPerLiquidityCumulativeX128,
                          tickCumulative,
                          time,
                          false,
                          maxLiquidityPerTick
                      );
                      flippedUpper = ticks.update(
                          tickUpper,
                          tick,
                          liquidityDelta,
                          _feeGrowthGlobal0X128,
                          _feeGrowthGlobal1X128,
                          secondsPerLiquidityCumulativeX128,
                          tickCumulative,
                          time,
                          true,
                          maxLiquidityPerTick
                      );
                      if (flippedLower) {
                          tickBitmap.flipTick(tickLower, tickSpacing);
                      }
                      if (flippedUpper) {
                          tickBitmap.flipTick(tickUpper, tickSpacing);
                      }
                  }
                  (uint256 feeGrowthInside0X128, uint256 feeGrowthInside1X128) =
                      ticks.getFeeGrowthInside(tickLower, tickUpper, tick, _feeGrowthGlobal0X128, _feeGrowthGlobal1X128);
                  position.update(liquidityDelta, feeGrowthInside0X128, feeGrowthInside1X128);
                  // clear any tick data that is no longer needed
                  if (liquidityDelta < 0) {
                      if (flippedLower) {
                          ticks.clear(tickLower);
                      }
                      if (flippedUpper) {
                          ticks.clear(tickUpper);
                      }
                  }
              }
              /// @inheritdoc IUniswapV3PoolActions
              /// @dev noDelegateCall is applied indirectly via _modifyPosition
              function mint(
                  address recipient,
                  int24 tickLower,
                  int24 tickUpper,
                  uint128 amount,
                  bytes calldata data
              ) external override lock returns (uint256 amount0, uint256 amount1) {
                  require(amount > 0);
                  (, int256 amount0Int, int256 amount1Int) =
                      _modifyPosition(
                          ModifyPositionParams({
                              owner: recipient,
                              tickLower: tickLower,
                              tickUpper: tickUpper,
                              liquidityDelta: int256(amount).toInt128()
                          })
                      );
                  amount0 = uint256(amount0Int);
                  amount1 = uint256(amount1Int);
                  uint256 balance0Before;
                  uint256 balance1Before;
                  if (amount0 > 0) balance0Before = balance0();
                  if (amount1 > 0) balance1Before = balance1();
                  IUniswapV3MintCallback(msg.sender).uniswapV3MintCallback(amount0, amount1, data);
                  if (amount0 > 0) require(balance0Before.add(amount0) <= balance0(), 'M0');
                  if (amount1 > 0) require(balance1Before.add(amount1) <= balance1(), 'M1');
                  emit Mint(msg.sender, recipient, tickLower, tickUpper, amount, amount0, amount1);
              }
              /// @inheritdoc IUniswapV3PoolActions
              function collect(
                  address recipient,
                  int24 tickLower,
                  int24 tickUpper,
                  uint128 amount0Requested,
                  uint128 amount1Requested
              ) external override lock returns (uint128 amount0, uint128 amount1) {
                  // we don't need to checkTicks here, because invalid positions will never have non-zero tokensOwed{0,1}
                  Position.Info storage position = positions.get(msg.sender, tickLower, tickUpper);
                  amount0 = amount0Requested > position.tokensOwed0 ? position.tokensOwed0 : amount0Requested;
                  amount1 = amount1Requested > position.tokensOwed1 ? position.tokensOwed1 : amount1Requested;
                  if (amount0 > 0) {
                      position.tokensOwed0 -= amount0;
                      TransferHelper.safeTransfer(token0, recipient, amount0);
                  }
                  if (amount1 > 0) {
                      position.tokensOwed1 -= amount1;
                      TransferHelper.safeTransfer(token1, recipient, amount1);
                  }
                  emit Collect(msg.sender, recipient, tickLower, tickUpper, amount0, amount1);
              }
              /// @inheritdoc IUniswapV3PoolActions
              /// @dev noDelegateCall is applied indirectly via _modifyPosition
              function burn(
                  int24 tickLower,
                  int24 tickUpper,
                  uint128 amount
              ) external override lock returns (uint256 amount0, uint256 amount1) {
                  (Position.Info storage position, int256 amount0Int, int256 amount1Int) =
                      _modifyPosition(
                          ModifyPositionParams({
                              owner: msg.sender,
                              tickLower: tickLower,
                              tickUpper: tickUpper,
                              liquidityDelta: -int256(amount).toInt128()
                          })
                      );
                  amount0 = uint256(-amount0Int);
                  amount1 = uint256(-amount1Int);
                  if (amount0 > 0 || amount1 > 0) {
                      (position.tokensOwed0, position.tokensOwed1) = (
                          position.tokensOwed0 + uint128(amount0),
                          position.tokensOwed1 + uint128(amount1)
                      );
                  }
                  emit Burn(msg.sender, tickLower, tickUpper, amount, amount0, amount1);
              }
              struct SwapCache {
                  // the protocol fee for the input token
                  uint8 feeProtocol;
                  // liquidity at the beginning of the swap
                  uint128 liquidityStart;
                  // the timestamp of the current block
                  uint32 blockTimestamp;
                  // the current value of the tick accumulator, computed only if we cross an initialized tick
                  int56 tickCumulative;
                  // the current value of seconds per liquidity accumulator, computed only if we cross an initialized tick
                  uint160 secondsPerLiquidityCumulativeX128;
                  // whether we've computed and cached the above two accumulators
                  bool computedLatestObservation;
              }
              // the top level state of the swap, the results of which are recorded in storage at the end
              struct SwapState {
                  // the amount remaining to be swapped in/out of the input/output asset
                  int256 amountSpecifiedRemaining;
                  // the amount already swapped out/in of the output/input asset
                  int256 amountCalculated;
                  // current sqrt(price)
                  uint160 sqrtPriceX96;
                  // the tick associated with the current price
                  int24 tick;
                  // the global fee growth of the input token
                  uint256 feeGrowthGlobalX128;
                  // amount of input token paid as protocol fee
                  uint128 protocolFee;
                  // the current liquidity in range
                  uint128 liquidity;
              }
              struct StepComputations {
                  // the price at the beginning of the step
                  uint160 sqrtPriceStartX96;
                  // the next tick to swap to from the current tick in the swap direction
                  int24 tickNext;
                  // whether tickNext is initialized or not
                  bool initialized;
                  // sqrt(price) for the next tick (1/0)
                  uint160 sqrtPriceNextX96;
                  // how much is being swapped in in this step
                  uint256 amountIn;
                  // how much is being swapped out
                  uint256 amountOut;
                  // how much fee is being paid in
                  uint256 feeAmount;
              }
              /// @inheritdoc IUniswapV3PoolActions
              function swap(
                  address recipient,
                  bool zeroForOne,
                  int256 amountSpecified,
                  uint160 sqrtPriceLimitX96,
                  bytes calldata data
              ) external override noDelegateCall returns (int256 amount0, int256 amount1) {
                  require(amountSpecified != 0, 'AS');
                  Slot0 memory slot0Start = slot0;
                  require(slot0Start.unlocked, 'LOK');
                  require(
                      zeroForOne
                          ? sqrtPriceLimitX96 < slot0Start.sqrtPriceX96 && sqrtPriceLimitX96 > TickMath.MIN_SQRT_RATIO
                          : sqrtPriceLimitX96 > slot0Start.sqrtPriceX96 && sqrtPriceLimitX96 < TickMath.MAX_SQRT_RATIO,
                      'SPL'
                  );
                  slot0.unlocked = false;
                  SwapCache memory cache =
                      SwapCache({
                          liquidityStart: liquidity,
                          blockTimestamp: _blockTimestamp(),
                          feeProtocol: zeroForOne ? (slot0Start.feeProtocol % 16) : (slot0Start.feeProtocol >> 4),
                          secondsPerLiquidityCumulativeX128: 0,
                          tickCumulative: 0,
                          computedLatestObservation: false
                      });
                  bool exactInput = amountSpecified > 0;
                  SwapState memory state =
                      SwapState({
                          amountSpecifiedRemaining: amountSpecified,
                          amountCalculated: 0,
                          sqrtPriceX96: slot0Start.sqrtPriceX96,
                          tick: slot0Start.tick,
                          feeGrowthGlobalX128: zeroForOne ? feeGrowthGlobal0X128 : feeGrowthGlobal1X128,
                          protocolFee: 0,
                          liquidity: cache.liquidityStart
                      });
                  // continue swapping as long as we haven't used the entire input/output and haven't reached the price limit
                  while (state.amountSpecifiedRemaining != 0 && state.sqrtPriceX96 != sqrtPriceLimitX96) {
                      StepComputations memory step;
                      step.sqrtPriceStartX96 = state.sqrtPriceX96;
                      (step.tickNext, step.initialized) = tickBitmap.nextInitializedTickWithinOneWord(
                          state.tick,
                          tickSpacing,
                          zeroForOne
                      );
                      // ensure that we do not overshoot the min/max tick, as the tick bitmap is not aware of these bounds
                      if (step.tickNext < TickMath.MIN_TICK) {
                          step.tickNext = TickMath.MIN_TICK;
                      } else if (step.tickNext > TickMath.MAX_TICK) {
                          step.tickNext = TickMath.MAX_TICK;
                      }
                      // get the price for the next tick
                      step.sqrtPriceNextX96 = TickMath.getSqrtRatioAtTick(step.tickNext);
                      // compute values to swap to the target tick, price limit, or point where input/output amount is exhausted
                      (state.sqrtPriceX96, step.amountIn, step.amountOut, step.feeAmount) = SwapMath.computeSwapStep(
                          state.sqrtPriceX96,
                          (zeroForOne ? step.sqrtPriceNextX96 < sqrtPriceLimitX96 : step.sqrtPriceNextX96 > sqrtPriceLimitX96)
                              ? sqrtPriceLimitX96
                              : step.sqrtPriceNextX96,
                          state.liquidity,
                          state.amountSpecifiedRemaining,
                          fee
                      );
                      if (exactInput) {
                          state.amountSpecifiedRemaining -= (step.amountIn + step.feeAmount).toInt256();
                          state.amountCalculated = state.amountCalculated.sub(step.amountOut.toInt256());
                      } else {
                          state.amountSpecifiedRemaining += step.amountOut.toInt256();
                          state.amountCalculated = state.amountCalculated.add((step.amountIn + step.feeAmount).toInt256());
                      }
                      // if the protocol fee is on, calculate how much is owed, decrement feeAmount, and increment protocolFee
                      if (cache.feeProtocol > 0) {
                          uint256 delta = step.feeAmount / cache.feeProtocol;
                          step.feeAmount -= delta;
                          state.protocolFee += uint128(delta);
                      }
                      // update global fee tracker
                      if (state.liquidity > 0)
                          state.feeGrowthGlobalX128 += FullMath.mulDiv(step.feeAmount, FixedPoint128.Q128, state.liquidity);
                      // shift tick if we reached the next price
                      if (state.sqrtPriceX96 == step.sqrtPriceNextX96) {
                          // if the tick is initialized, run the tick transition
                          if (step.initialized) {
                              // check for the placeholder value, which we replace with the actual value the first time the swap
                              // crosses an initialized tick
                              if (!cache.computedLatestObservation) {
                                  (cache.tickCumulative, cache.secondsPerLiquidityCumulativeX128) = observations.observeSingle(
                                      cache.blockTimestamp,
                                      0,
                                      slot0Start.tick,
                                      slot0Start.observationIndex,
                                      cache.liquidityStart,
                                      slot0Start.observationCardinality
                                  );
                                  cache.computedLatestObservation = true;
                              }
                              int128 liquidityNet =
                                  ticks.cross(
                                      step.tickNext,
                                      (zeroForOne ? state.feeGrowthGlobalX128 : feeGrowthGlobal0X128),
                                      (zeroForOne ? feeGrowthGlobal1X128 : state.feeGrowthGlobalX128),
                                      cache.secondsPerLiquidityCumulativeX128,
                                      cache.tickCumulative,
                                      cache.blockTimestamp
                                  );
                              // if we're moving leftward, we interpret liquidityNet as the opposite sign
                              // safe because liquidityNet cannot be type(int128).min
                              if (zeroForOne) liquidityNet = -liquidityNet;
                              state.liquidity = LiquidityMath.addDelta(state.liquidity, liquidityNet);
                          }
                          state.tick = zeroForOne ? step.tickNext - 1 : step.tickNext;
                      } else if (state.sqrtPriceX96 != step.sqrtPriceStartX96) {
                          // recompute unless we're on a lower tick boundary (i.e. already transitioned ticks), and haven't moved
                          state.tick = TickMath.getTickAtSqrtRatio(state.sqrtPriceX96);
                      }
                  }
                  // update tick and write an oracle entry if the tick change
                  if (state.tick != slot0Start.tick) {
                      (uint16 observationIndex, uint16 observationCardinality) =
                          observations.write(
                              slot0Start.observationIndex,
                              cache.blockTimestamp,
                              slot0Start.tick,
                              cache.liquidityStart,
                              slot0Start.observationCardinality,
                              slot0Start.observationCardinalityNext
                          );
                      (slot0.sqrtPriceX96, slot0.tick, slot0.observationIndex, slot0.observationCardinality) = (
                          state.sqrtPriceX96,
                          state.tick,
                          observationIndex,
                          observationCardinality
                      );
                  } else {
                      // otherwise just update the price
                      slot0.sqrtPriceX96 = state.sqrtPriceX96;
                  }
                  // update liquidity if it changed
                  if (cache.liquidityStart != state.liquidity) liquidity = state.liquidity;
                  // update fee growth global and, if necessary, protocol fees
                  // overflow is acceptable, protocol has to withdraw before it hits type(uint128).max fees
                  if (zeroForOne) {
                      feeGrowthGlobal0X128 = state.feeGrowthGlobalX128;
                      if (state.protocolFee > 0) protocolFees.token0 += state.protocolFee;
                  } else {
                      feeGrowthGlobal1X128 = state.feeGrowthGlobalX128;
                      if (state.protocolFee > 0) protocolFees.token1 += state.protocolFee;
                  }
                  (amount0, amount1) = zeroForOne == exactInput
                      ? (amountSpecified - state.amountSpecifiedRemaining, state.amountCalculated)
                      : (state.amountCalculated, amountSpecified - state.amountSpecifiedRemaining);
                  // do the transfers and collect payment
                  if (zeroForOne) {
                      if (amount1 < 0) TransferHelper.safeTransfer(token1, recipient, uint256(-amount1));
                      uint256 balance0Before = balance0();
                      IUniswapV3SwapCallback(msg.sender).uniswapV3SwapCallback(amount0, amount1, data);
                      require(balance0Before.add(uint256(amount0)) <= balance0(), 'IIA');
                  } else {
                      if (amount0 < 0) TransferHelper.safeTransfer(token0, recipient, uint256(-amount0));
                      uint256 balance1Before = balance1();
                      IUniswapV3SwapCallback(msg.sender).uniswapV3SwapCallback(amount0, amount1, data);
                      require(balance1Before.add(uint256(amount1)) <= balance1(), 'IIA');
                  }
                  emit Swap(msg.sender, recipient, amount0, amount1, state.sqrtPriceX96, state.liquidity, state.tick);
                  slot0.unlocked = true;
              }
              /// @inheritdoc IUniswapV3PoolActions
              function flash(
                  address recipient,
                  uint256 amount0,
                  uint256 amount1,
                  bytes calldata data
              ) external override lock noDelegateCall {
                  uint128 _liquidity = liquidity;
                  require(_liquidity > 0, 'L');
                  uint256 fee0 = FullMath.mulDivRoundingUp(amount0, fee, 1e6);
                  uint256 fee1 = FullMath.mulDivRoundingUp(amount1, fee, 1e6);
                  uint256 balance0Before = balance0();
                  uint256 balance1Before = balance1();
                  if (amount0 > 0) TransferHelper.safeTransfer(token0, recipient, amount0);
                  if (amount1 > 0) TransferHelper.safeTransfer(token1, recipient, amount1);
                  IUniswapV3FlashCallback(msg.sender).uniswapV3FlashCallback(fee0, fee1, data);
                  uint256 balance0After = balance0();
                  uint256 balance1After = balance1();
                  require(balance0Before.add(fee0) <= balance0After, 'F0');
                  require(balance1Before.add(fee1) <= balance1After, 'F1');
                  // sub is safe because we know balanceAfter is gt balanceBefore by at least fee
                  uint256 paid0 = balance0After - balance0Before;
                  uint256 paid1 = balance1After - balance1Before;
                  if (paid0 > 0) {
                      uint8 feeProtocol0 = slot0.feeProtocol % 16;
                      uint256 fees0 = feeProtocol0 == 0 ? 0 : paid0 / feeProtocol0;
                      if (uint128(fees0) > 0) protocolFees.token0 += uint128(fees0);
                      feeGrowthGlobal0X128 += FullMath.mulDiv(paid0 - fees0, FixedPoint128.Q128, _liquidity);
                  }
                  if (paid1 > 0) {
                      uint8 feeProtocol1 = slot0.feeProtocol >> 4;
                      uint256 fees1 = feeProtocol1 == 0 ? 0 : paid1 / feeProtocol1;
                      if (uint128(fees1) > 0) protocolFees.token1 += uint128(fees1);
                      feeGrowthGlobal1X128 += FullMath.mulDiv(paid1 - fees1, FixedPoint128.Q128, _liquidity);
                  }
                  emit Flash(msg.sender, recipient, amount0, amount1, paid0, paid1);
              }
              /// @inheritdoc IUniswapV3PoolOwnerActions
              function setFeeProtocol(uint8 feeProtocol0, uint8 feeProtocol1) external override lock onlyFactoryOwner {
                  require(
                      (feeProtocol0 == 0 || (feeProtocol0 >= 4 && feeProtocol0 <= 10)) &&
                          (feeProtocol1 == 0 || (feeProtocol1 >= 4 && feeProtocol1 <= 10))
                  );
                  uint8 feeProtocolOld = slot0.feeProtocol;
                  slot0.feeProtocol = feeProtocol0 + (feeProtocol1 << 4);
                  emit SetFeeProtocol(feeProtocolOld % 16, feeProtocolOld >> 4, feeProtocol0, feeProtocol1);
              }
              /// @inheritdoc IUniswapV3PoolOwnerActions
              function collectProtocol(
                  address recipient,
                  uint128 amount0Requested,
                  uint128 amount1Requested
              ) external override lock onlyFactoryOwner returns (uint128 amount0, uint128 amount1) {
                  amount0 = amount0Requested > protocolFees.token0 ? protocolFees.token0 : amount0Requested;
                  amount1 = amount1Requested > protocolFees.token1 ? protocolFees.token1 : amount1Requested;
                  if (amount0 > 0) {
                      if (amount0 == protocolFees.token0) amount0--; // ensure that the slot is not cleared, for gas savings
                      protocolFees.token0 -= amount0;
                      TransferHelper.safeTransfer(token0, recipient, amount0);
                  }
                  if (amount1 > 0) {
                      if (amount1 == protocolFees.token1) amount1--; // ensure that the slot is not cleared, for gas savings
                      protocolFees.token1 -= amount1;
                      TransferHelper.safeTransfer(token1, recipient, amount1);
                  }
                  emit CollectProtocol(msg.sender, recipient, amount0, amount1);
              }
          }
          // SPDX-License-Identifier: GPL-2.0-or-later
          pragma solidity >=0.5.0;
          import './pool/IUniswapV3PoolImmutables.sol';
          import './pool/IUniswapV3PoolState.sol';
          import './pool/IUniswapV3PoolDerivedState.sol';
          import './pool/IUniswapV3PoolActions.sol';
          import './pool/IUniswapV3PoolOwnerActions.sol';
          import './pool/IUniswapV3PoolEvents.sol';
          /// @title The interface for a Uniswap V3 Pool
          /// @notice A Uniswap pool facilitates swapping and automated market making between any two assets that strictly conform
          /// to the ERC20 specification
          /// @dev The pool interface is broken up into many smaller pieces
          interface IUniswapV3Pool is
              IUniswapV3PoolImmutables,
              IUniswapV3PoolState,
              IUniswapV3PoolDerivedState,
              IUniswapV3PoolActions,
              IUniswapV3PoolOwnerActions,
              IUniswapV3PoolEvents
          {
          }
          // SPDX-License-Identifier: BUSL-1.1
          pragma solidity =0.7.6;
          /// @title Prevents delegatecall to a contract
          /// @notice Base contract that provides a modifier for preventing delegatecall to methods in a child contract
          abstract contract NoDelegateCall {
              /// @dev The original address of this contract
              address private immutable original;
              constructor() {
                  // Immutables are computed in the init code of the contract, and then inlined into the deployed bytecode.
                  // In other words, this variable won't change when it's checked at runtime.
                  original = address(this);
              }
              /// @dev Private method is used instead of inlining into modifier because modifiers are copied into each method,
              ///     and the use of immutable means the address bytes are copied in every place the modifier is used.
              function checkNotDelegateCall() private view {
                  require(address(this) == original);
              }
              /// @notice Prevents delegatecall into the modified method
              modifier noDelegateCall() {
                  checkNotDelegateCall();
                  _;
              }
          }
          // SPDX-License-Identifier: GPL-2.0-or-later
          pragma solidity >=0.7.0;
          /// @title Optimized overflow and underflow safe math operations
          /// @notice Contains methods for doing math operations that revert on overflow or underflow for minimal gas cost
          library LowGasSafeMath {
              /// @notice Returns x + y, reverts if sum overflows uint256
              /// @param x The augend
              /// @param y The addend
              /// @return z The sum of x and y
              function add(uint256 x, uint256 y) internal pure returns (uint256 z) {
                  require((z = x + y) >= x);
              }
              /// @notice Returns x - y, reverts if underflows
              /// @param x The minuend
              /// @param y The subtrahend
              /// @return z The difference of x and y
              function sub(uint256 x, uint256 y) internal pure returns (uint256 z) {
                  require((z = x - y) <= x);
              }
              /// @notice Returns x * y, reverts if overflows
              /// @param x The multiplicand
              /// @param y The multiplier
              /// @return z The product of x and y
              function mul(uint256 x, uint256 y) internal pure returns (uint256 z) {
                  require(x == 0 || (z = x * y) / x == y);
              }
              /// @notice Returns x + y, reverts if overflows or underflows
              /// @param x The augend
              /// @param y The addend
              /// @return z The sum of x and y
              function add(int256 x, int256 y) internal pure returns (int256 z) {
                  require((z = x + y) >= x == (y >= 0));
              }
              /// @notice Returns x - y, reverts if overflows or underflows
              /// @param x The minuend
              /// @param y The subtrahend
              /// @return z The difference of x and y
              function sub(int256 x, int256 y) internal pure returns (int256 z) {
                  require((z = x - y) <= x == (y >= 0));
              }
          }
          // SPDX-License-Identifier: GPL-2.0-or-later
          pragma solidity >=0.5.0;
          /// @title Safe casting methods
          /// @notice Contains methods for safely casting between types
          library SafeCast {
              /// @notice Cast a uint256 to a uint160, revert on overflow
              /// @param y The uint256 to be downcasted
              /// @return z The downcasted integer, now type uint160
              function toUint160(uint256 y) internal pure returns (uint160 z) {
                  require((z = uint160(y)) == y);
              }
              /// @notice Cast a int256 to a int128, revert on overflow or underflow
              /// @param y The int256 to be downcasted
              /// @return z The downcasted integer, now type int128
              function toInt128(int256 y) internal pure returns (int128 z) {
                  require((z = int128(y)) == y);
              }
              /// @notice Cast a uint256 to a int256, revert on overflow
              /// @param y The uint256 to be casted
              /// @return z The casted integer, now type int256
              function toInt256(uint256 y) internal pure returns (int256 z) {
                  require(y < 2**255);
                  z = int256(y);
              }
          }
          // SPDX-License-Identifier: BUSL-1.1
          pragma solidity >=0.5.0;
          import './LowGasSafeMath.sol';
          import './SafeCast.sol';
          import './TickMath.sol';
          import './LiquidityMath.sol';
          /// @title Tick
          /// @notice Contains functions for managing tick processes and relevant calculations
          library Tick {
              using LowGasSafeMath for int256;
              using SafeCast for int256;
              // info stored for each initialized individual tick
              struct Info {
                  // the total position liquidity that references this tick
                  uint128 liquidityGross;
                  // amount of net liquidity added (subtracted) when tick is crossed from left to right (right to left),
                  int128 liquidityNet;
                  // fee growth per unit of liquidity on the _other_ side of this tick (relative to the current tick)
                  // only has relative meaning, not absolute — the value depends on when the tick is initialized
                  uint256 feeGrowthOutside0X128;
                  uint256 feeGrowthOutside1X128;
                  // the cumulative tick value on the other side of the tick
                  int56 tickCumulativeOutside;
                  // the seconds per unit of liquidity on the _other_ side of this tick (relative to the current tick)
                  // only has relative meaning, not absolute — the value depends on when the tick is initialized
                  uint160 secondsPerLiquidityOutsideX128;
                  // the seconds spent on the other side of the tick (relative to the current tick)
                  // only has relative meaning, not absolute — the value depends on when the tick is initialized
                  uint32 secondsOutside;
                  // true iff the tick is initialized, i.e. the value is exactly equivalent to the expression liquidityGross != 0
                  // these 8 bits are set to prevent fresh sstores when crossing newly initialized ticks
                  bool initialized;
              }
              /// @notice Derives max liquidity per tick from given tick spacing
              /// @dev Executed within the pool constructor
              /// @param tickSpacing The amount of required tick separation, realized in multiples of `tickSpacing`
              ///     e.g., a tickSpacing of 3 requires ticks to be initialized every 3rd tick i.e., ..., -6, -3, 0, 3, 6, ...
              /// @return The max liquidity per tick
              function tickSpacingToMaxLiquidityPerTick(int24 tickSpacing) internal pure returns (uint128) {
                  int24 minTick = (TickMath.MIN_TICK / tickSpacing) * tickSpacing;
                  int24 maxTick = (TickMath.MAX_TICK / tickSpacing) * tickSpacing;
                  uint24 numTicks = uint24((maxTick - minTick) / tickSpacing) + 1;
                  return type(uint128).max / numTicks;
              }
              /// @notice Retrieves fee growth data
              /// @param self The mapping containing all tick information for initialized ticks
              /// @param tickLower The lower tick boundary of the position
              /// @param tickUpper The upper tick boundary of the position
              /// @param tickCurrent The current tick
              /// @param feeGrowthGlobal0X128 The all-time global fee growth, per unit of liquidity, in token0
              /// @param feeGrowthGlobal1X128 The all-time global fee growth, per unit of liquidity, in token1
              /// @return feeGrowthInside0X128 The all-time fee growth in token0, per unit of liquidity, inside the position's tick boundaries
              /// @return feeGrowthInside1X128 The all-time fee growth in token1, per unit of liquidity, inside the position's tick boundaries
              function getFeeGrowthInside(
                  mapping(int24 => Tick.Info) storage self,
                  int24 tickLower,
                  int24 tickUpper,
                  int24 tickCurrent,
                  uint256 feeGrowthGlobal0X128,
                  uint256 feeGrowthGlobal1X128
              ) internal view returns (uint256 feeGrowthInside0X128, uint256 feeGrowthInside1X128) {
                  Info storage lower = self[tickLower];
                  Info storage upper = self[tickUpper];
                  // calculate fee growth below
                  uint256 feeGrowthBelow0X128;
                  uint256 feeGrowthBelow1X128;
                  if (tickCurrent >= tickLower) {
                      feeGrowthBelow0X128 = lower.feeGrowthOutside0X128;
                      feeGrowthBelow1X128 = lower.feeGrowthOutside1X128;
                  } else {
                      feeGrowthBelow0X128 = feeGrowthGlobal0X128 - lower.feeGrowthOutside0X128;
                      feeGrowthBelow1X128 = feeGrowthGlobal1X128 - lower.feeGrowthOutside1X128;
                  }
                  // calculate fee growth above
                  uint256 feeGrowthAbove0X128;
                  uint256 feeGrowthAbove1X128;
                  if (tickCurrent < tickUpper) {
                      feeGrowthAbove0X128 = upper.feeGrowthOutside0X128;
                      feeGrowthAbove1X128 = upper.feeGrowthOutside1X128;
                  } else {
                      feeGrowthAbove0X128 = feeGrowthGlobal0X128 - upper.feeGrowthOutside0X128;
                      feeGrowthAbove1X128 = feeGrowthGlobal1X128 - upper.feeGrowthOutside1X128;
                  }
                  feeGrowthInside0X128 = feeGrowthGlobal0X128 - feeGrowthBelow0X128 - feeGrowthAbove0X128;
                  feeGrowthInside1X128 = feeGrowthGlobal1X128 - feeGrowthBelow1X128 - feeGrowthAbove1X128;
              }
              /// @notice Updates a tick and returns true if the tick was flipped from initialized to uninitialized, or vice versa
              /// @param self The mapping containing all tick information for initialized ticks
              /// @param tick The tick that will be updated
              /// @param tickCurrent The current tick
              /// @param liquidityDelta A new amount of liquidity to be added (subtracted) when tick is crossed from left to right (right to left)
              /// @param feeGrowthGlobal0X128 The all-time global fee growth, per unit of liquidity, in token0
              /// @param feeGrowthGlobal1X128 The all-time global fee growth, per unit of liquidity, in token1
              /// @param secondsPerLiquidityCumulativeX128 The all-time seconds per max(1, liquidity) of the pool
              /// @param time The current block timestamp cast to a uint32
              /// @param upper true for updating a position's upper tick, or false for updating a position's lower tick
              /// @param maxLiquidity The maximum liquidity allocation for a single tick
              /// @return flipped Whether the tick was flipped from initialized to uninitialized, or vice versa
              function update(
                  mapping(int24 => Tick.Info) storage self,
                  int24 tick,
                  int24 tickCurrent,
                  int128 liquidityDelta,
                  uint256 feeGrowthGlobal0X128,
                  uint256 feeGrowthGlobal1X128,
                  uint160 secondsPerLiquidityCumulativeX128,
                  int56 tickCumulative,
                  uint32 time,
                  bool upper,
                  uint128 maxLiquidity
              ) internal returns (bool flipped) {
                  Tick.Info storage info = self[tick];
                  uint128 liquidityGrossBefore = info.liquidityGross;
                  uint128 liquidityGrossAfter = LiquidityMath.addDelta(liquidityGrossBefore, liquidityDelta);
                  require(liquidityGrossAfter <= maxLiquidity, 'LO');
                  flipped = (liquidityGrossAfter == 0) != (liquidityGrossBefore == 0);
                  if (liquidityGrossBefore == 0) {
                      // by convention, we assume that all growth before a tick was initialized happened _below_ the tick
                      if (tick <= tickCurrent) {
                          info.feeGrowthOutside0X128 = feeGrowthGlobal0X128;
                          info.feeGrowthOutside1X128 = feeGrowthGlobal1X128;
                          info.secondsPerLiquidityOutsideX128 = secondsPerLiquidityCumulativeX128;
                          info.tickCumulativeOutside = tickCumulative;
                          info.secondsOutside = time;
                      }
                      info.initialized = true;
                  }
                  info.liquidityGross = liquidityGrossAfter;
                  // when the lower (upper) tick is crossed left to right (right to left), liquidity must be added (removed)
                  info.liquidityNet = upper
                      ? int256(info.liquidityNet).sub(liquidityDelta).toInt128()
                      : int256(info.liquidityNet).add(liquidityDelta).toInt128();
              }
              /// @notice Clears tick data
              /// @param self The mapping containing all initialized tick information for initialized ticks
              /// @param tick The tick that will be cleared
              function clear(mapping(int24 => Tick.Info) storage self, int24 tick) internal {
                  delete self[tick];
              }
              /// @notice Transitions to next tick as needed by price movement
              /// @param self The mapping containing all tick information for initialized ticks
              /// @param tick The destination tick of the transition
              /// @param feeGrowthGlobal0X128 The all-time global fee growth, per unit of liquidity, in token0
              /// @param feeGrowthGlobal1X128 The all-time global fee growth, per unit of liquidity, in token1
              /// @param secondsPerLiquidityCumulativeX128 The current seconds per liquidity
              /// @param time The current block.timestamp
              /// @return liquidityNet The amount of liquidity added (subtracted) when tick is crossed from left to right (right to left)
              function cross(
                  mapping(int24 => Tick.Info) storage self,
                  int24 tick,
                  uint256 feeGrowthGlobal0X128,
                  uint256 feeGrowthGlobal1X128,
                  uint160 secondsPerLiquidityCumulativeX128,
                  int56 tickCumulative,
                  uint32 time
              ) internal returns (int128 liquidityNet) {
                  Tick.Info storage info = self[tick];
                  info.feeGrowthOutside0X128 = feeGrowthGlobal0X128 - info.feeGrowthOutside0X128;
                  info.feeGrowthOutside1X128 = feeGrowthGlobal1X128 - info.feeGrowthOutside1X128;
                  info.secondsPerLiquidityOutsideX128 = secondsPerLiquidityCumulativeX128 - info.secondsPerLiquidityOutsideX128;
                  info.tickCumulativeOutside = tickCumulative - info.tickCumulativeOutside;
                  info.secondsOutside = time - info.secondsOutside;
                  liquidityNet = info.liquidityNet;
              }
          }
          // SPDX-License-Identifier: BUSL-1.1
          pragma solidity >=0.5.0;
          import './BitMath.sol';
          /// @title Packed tick initialized state library
          /// @notice Stores a packed mapping of tick index to its initialized state
          /// @dev The mapping uses int16 for keys since ticks are represented as int24 and there are 256 (2^8) values per word.
          library TickBitmap {
              /// @notice Computes the position in the mapping where the initialized bit for a tick lives
              /// @param tick The tick for which to compute the position
              /// @return wordPos The key in the mapping containing the word in which the bit is stored
              /// @return bitPos The bit position in the word where the flag is stored
              function position(int24 tick) private pure returns (int16 wordPos, uint8 bitPos) {
                  wordPos = int16(tick >> 8);
                  bitPos = uint8(tick % 256);
              }
              /// @notice Flips the initialized state for a given tick from false to true, or vice versa
              /// @param self The mapping in which to flip the tick
              /// @param tick The tick to flip
              /// @param tickSpacing The spacing between usable ticks
              function flipTick(
                  mapping(int16 => uint256) storage self,
                  int24 tick,
                  int24 tickSpacing
              ) internal {
                  require(tick % tickSpacing == 0); // ensure that the tick is spaced
                  (int16 wordPos, uint8 bitPos) = position(tick / tickSpacing);
                  uint256 mask = 1 << bitPos;
                  self[wordPos] ^= mask;
              }
              /// @notice Returns the next initialized tick contained in the same word (or adjacent word) as the tick that is either
              /// to the left (less than or equal to) or right (greater than) of the given tick
              /// @param self The mapping in which to compute the next initialized tick
              /// @param tick The starting tick
              /// @param tickSpacing The spacing between usable ticks
              /// @param lte Whether to search for the next initialized tick to the left (less than or equal to the starting tick)
              /// @return next The next initialized or uninitialized tick up to 256 ticks away from the current tick
              /// @return initialized Whether the next tick is initialized, as the function only searches within up to 256 ticks
              function nextInitializedTickWithinOneWord(
                  mapping(int16 => uint256) storage self,
                  int24 tick,
                  int24 tickSpacing,
                  bool lte
              ) internal view returns (int24 next, bool initialized) {
                  int24 compressed = tick / tickSpacing;
                  if (tick < 0 && tick % tickSpacing != 0) compressed--; // round towards negative infinity
                  if (lte) {
                      (int16 wordPos, uint8 bitPos) = position(compressed);
                      // all the 1s at or to the right of the current bitPos
                      uint256 mask = (1 << bitPos) - 1 + (1 << bitPos);
                      uint256 masked = self[wordPos] & mask;
                      // if there are no initialized ticks to the right of or at the current tick, return rightmost in the word
                      initialized = masked != 0;
                      // overflow/underflow is possible, but prevented externally by limiting both tickSpacing and tick
                      next = initialized
                          ? (compressed - int24(bitPos - BitMath.mostSignificantBit(masked))) * tickSpacing
                          : (compressed - int24(bitPos)) * tickSpacing;
                  } else {
                      // start from the word of the next tick, since the current tick state doesn't matter
                      (int16 wordPos, uint8 bitPos) = position(compressed + 1);
                      // all the 1s at or to the left of the bitPos
                      uint256 mask = ~((1 << bitPos) - 1);
                      uint256 masked = self[wordPos] & mask;
                      // if there are no initialized ticks to the left of the current tick, return leftmost in the word
                      initialized = masked != 0;
                      // overflow/underflow is possible, but prevented externally by limiting both tickSpacing and tick
                      next = initialized
                          ? (compressed + 1 + int24(BitMath.leastSignificantBit(masked) - bitPos)) * tickSpacing
                          : (compressed + 1 + int24(type(uint8).max - bitPos)) * tickSpacing;
                  }
              }
          }
          // SPDX-License-Identifier: BUSL-1.1
          pragma solidity >=0.5.0;
          import './FullMath.sol';
          import './FixedPoint128.sol';
          import './LiquidityMath.sol';
          /// @title Position
          /// @notice Positions represent an owner address' liquidity between a lower and upper tick boundary
          /// @dev Positions store additional state for tracking fees owed to the position
          library Position {
              // info stored for each user's position
              struct Info {
                  // the amount of liquidity owned by this position
                  uint128 liquidity;
                  // fee growth per unit of liquidity as of the last update to liquidity or fees owed
                  uint256 feeGrowthInside0LastX128;
                  uint256 feeGrowthInside1LastX128;
                  // the fees owed to the position owner in token0/token1
                  uint128 tokensOwed0;
                  uint128 tokensOwed1;
              }
              /// @notice Returns the Info struct of a position, given an owner and position boundaries
              /// @param self The mapping containing all user positions
              /// @param owner The address of the position owner
              /// @param tickLower The lower tick boundary of the position
              /// @param tickUpper The upper tick boundary of the position
              /// @return position The position info struct of the given owners' position
              function get(
                  mapping(bytes32 => Info) storage self,
                  address owner,
                  int24 tickLower,
                  int24 tickUpper
              ) internal view returns (Position.Info storage position) {
                  position = self[keccak256(abi.encodePacked(owner, tickLower, tickUpper))];
              }
              /// @notice Credits accumulated fees to a user's position
              /// @param self The individual position to update
              /// @param liquidityDelta The change in pool liquidity as a result of the position update
              /// @param feeGrowthInside0X128 The all-time fee growth in token0, per unit of liquidity, inside the position's tick boundaries
              /// @param feeGrowthInside1X128 The all-time fee growth in token1, per unit of liquidity, inside the position's tick boundaries
              function update(
                  Info storage self,
                  int128 liquidityDelta,
                  uint256 feeGrowthInside0X128,
                  uint256 feeGrowthInside1X128
              ) internal {
                  Info memory _self = self;
                  uint128 liquidityNext;
                  if (liquidityDelta == 0) {
                      require(_self.liquidity > 0, 'NP'); // disallow pokes for 0 liquidity positions
                      liquidityNext = _self.liquidity;
                  } else {
                      liquidityNext = LiquidityMath.addDelta(_self.liquidity, liquidityDelta);
                  }
                  // calculate accumulated fees
                  uint128 tokensOwed0 =
                      uint128(
                          FullMath.mulDiv(
                              feeGrowthInside0X128 - _self.feeGrowthInside0LastX128,
                              _self.liquidity,
                              FixedPoint128.Q128
                          )
                      );
                  uint128 tokensOwed1 =
                      uint128(
                          FullMath.mulDiv(
                              feeGrowthInside1X128 - _self.feeGrowthInside1LastX128,
                              _self.liquidity,
                              FixedPoint128.Q128
                          )
                      );
                  // update the position
                  if (liquidityDelta != 0) self.liquidity = liquidityNext;
                  self.feeGrowthInside0LastX128 = feeGrowthInside0X128;
                  self.feeGrowthInside1LastX128 = feeGrowthInside1X128;
                  if (tokensOwed0 > 0 || tokensOwed1 > 0) {
                      // overflow is acceptable, have to withdraw before you hit type(uint128).max fees
                      self.tokensOwed0 += tokensOwed0;
                      self.tokensOwed1 += tokensOwed1;
                  }
              }
          }
          // SPDX-License-Identifier: BUSL-1.1
          pragma solidity >=0.5.0;
          /// @title Oracle
          /// @notice Provides price and liquidity data useful for a wide variety of system designs
          /// @dev Instances of stored oracle data, "observations", are collected in the oracle array
          /// Every pool is initialized with an oracle array length of 1. Anyone can pay the SSTOREs to increase the
          /// maximum length of the oracle array. New slots will be added when the array is fully populated.
          /// Observations are overwritten when the full length of the oracle array is populated.
          /// The most recent observation is available, independent of the length of the oracle array, by passing 0 to observe()
          library Oracle {
              struct Observation {
                  // the block timestamp of the observation
                  uint32 blockTimestamp;
                  // the tick accumulator, i.e. tick * time elapsed since the pool was first initialized
                  int56 tickCumulative;
                  // the seconds per liquidity, i.e. seconds elapsed / max(1, liquidity) since the pool was first initialized
                  uint160 secondsPerLiquidityCumulativeX128;
                  // whether or not the observation is initialized
                  bool initialized;
              }
              /// @notice Transforms a previous observation into a new observation, given the passage of time and the current tick and liquidity values
              /// @dev blockTimestamp _must_ be chronologically equal to or greater than last.blockTimestamp, safe for 0 or 1 overflows
              /// @param last The specified observation to be transformed
              /// @param blockTimestamp The timestamp of the new observation
              /// @param tick The active tick at the time of the new observation
              /// @param liquidity The total in-range liquidity at the time of the new observation
              /// @return Observation The newly populated observation
              function transform(
                  Observation memory last,
                  uint32 blockTimestamp,
                  int24 tick,
                  uint128 liquidity
              ) private pure returns (Observation memory) {
                  uint32 delta = blockTimestamp - last.blockTimestamp;
                  return
                      Observation({
                          blockTimestamp: blockTimestamp,
                          tickCumulative: last.tickCumulative + int56(tick) * delta,
                          secondsPerLiquidityCumulativeX128: last.secondsPerLiquidityCumulativeX128 +
                              ((uint160(delta) << 128) / (liquidity > 0 ? liquidity : 1)),
                          initialized: true
                      });
              }
              /// @notice Initialize the oracle array by writing the first slot. Called once for the lifecycle of the observations array
              /// @param self The stored oracle array
              /// @param time The time of the oracle initialization, via block.timestamp truncated to uint32
              /// @return cardinality The number of populated elements in the oracle array
              /// @return cardinalityNext The new length of the oracle array, independent of population
              function initialize(Observation[65535] storage self, uint32 time)
                  internal
                  returns (uint16 cardinality, uint16 cardinalityNext)
              {
                  self[0] = Observation({
                      blockTimestamp: time,
                      tickCumulative: 0,
                      secondsPerLiquidityCumulativeX128: 0,
                      initialized: true
                  });
                  return (1, 1);
              }
              /// @notice Writes an oracle observation to the array
              /// @dev Writable at most once per block. Index represents the most recently written element. cardinality and index must be tracked externally.
              /// If the index is at the end of the allowable array length (according to cardinality), and the next cardinality
              /// is greater than the current one, cardinality may be increased. This restriction is created to preserve ordering.
              /// @param self The stored oracle array
              /// @param index The index of the observation that was most recently written to the observations array
              /// @param blockTimestamp The timestamp of the new observation
              /// @param tick The active tick at the time of the new observation
              /// @param liquidity The total in-range liquidity at the time of the new observation
              /// @param cardinality The number of populated elements in the oracle array
              /// @param cardinalityNext The new length of the oracle array, independent of population
              /// @return indexUpdated The new index of the most recently written element in the oracle array
              /// @return cardinalityUpdated The new cardinality of the oracle array
              function write(
                  Observation[65535] storage self,
                  uint16 index,
                  uint32 blockTimestamp,
                  int24 tick,
                  uint128 liquidity,
                  uint16 cardinality,
                  uint16 cardinalityNext
              ) internal returns (uint16 indexUpdated, uint16 cardinalityUpdated) {
                  Observation memory last = self[index];
                  // early return if we've already written an observation this block
                  if (last.blockTimestamp == blockTimestamp) return (index, cardinality);
                  // if the conditions are right, we can bump the cardinality
                  if (cardinalityNext > cardinality && index == (cardinality - 1)) {
                      cardinalityUpdated = cardinalityNext;
                  } else {
                      cardinalityUpdated = cardinality;
                  }
                  indexUpdated = (index + 1) % cardinalityUpdated;
                  self[indexUpdated] = transform(last, blockTimestamp, tick, liquidity);
              }
              /// @notice Prepares the oracle array to store up to `next` observations
              /// @param self The stored oracle array
              /// @param current The current next cardinality of the oracle array
              /// @param next The proposed next cardinality which will be populated in the oracle array
              /// @return next The next cardinality which will be populated in the oracle array
              function grow(
                  Observation[65535] storage self,
                  uint16 current,
                  uint16 next
              ) internal returns (uint16) {
                  require(current > 0, 'I');
                  // no-op if the passed next value isn't greater than the current next value
                  if (next <= current) return current;
                  // store in each slot to prevent fresh SSTOREs in swaps
                  // this data will not be used because the initialized boolean is still false
                  for (uint16 i = current; i < next; i++) self[i].blockTimestamp = 1;
                  return next;
              }
              /// @notice comparator for 32-bit timestamps
              /// @dev safe for 0 or 1 overflows, a and b _must_ be chronologically before or equal to time
              /// @param time A timestamp truncated to 32 bits
              /// @param a A comparison timestamp from which to determine the relative position of `time`
              /// @param b From which to determine the relative position of `time`
              /// @return bool Whether `a` is chronologically <= `b`
              function lte(
                  uint32 time,
                  uint32 a,
                  uint32 b
              ) private pure returns (bool) {
                  // if there hasn't been overflow, no need to adjust
                  if (a <= time && b <= time) return a <= b;
                  uint256 aAdjusted = a > time ? a : a + 2**32;
                  uint256 bAdjusted = b > time ? b : b + 2**32;
                  return aAdjusted <= bAdjusted;
              }
              /// @notice Fetches the observations beforeOrAt and atOrAfter a target, i.e. where [beforeOrAt, atOrAfter] is satisfied.
              /// The result may be the same observation, or adjacent observations.
              /// @dev The answer must be contained in the array, used when the target is located within the stored observation
              /// boundaries: older than the most recent observation and younger, or the same age as, the oldest observation
              /// @param self The stored oracle array
              /// @param time The current block.timestamp
              /// @param target The timestamp at which the reserved observation should be for
              /// @param index The index of the observation that was most recently written to the observations array
              /// @param cardinality The number of populated elements in the oracle array
              /// @return beforeOrAt The observation recorded before, or at, the target
              /// @return atOrAfter The observation recorded at, or after, the target
              function binarySearch(
                  Observation[65535] storage self,
                  uint32 time,
                  uint32 target,
                  uint16 index,
                  uint16 cardinality
              ) private view returns (Observation memory beforeOrAt, Observation memory atOrAfter) {
                  uint256 l = (index + 1) % cardinality; // oldest observation
                  uint256 r = l + cardinality - 1; // newest observation
                  uint256 i;
                  while (true) {
                      i = (l + r) / 2;
                      beforeOrAt = self[i % cardinality];
                      // we've landed on an uninitialized tick, keep searching higher (more recently)
                      if (!beforeOrAt.initialized) {
                          l = i + 1;
                          continue;
                      }
                      atOrAfter = self[(i + 1) % cardinality];
                      bool targetAtOrAfter = lte(time, beforeOrAt.blockTimestamp, target);
                      // check if we've found the answer!
                      if (targetAtOrAfter && lte(time, target, atOrAfter.blockTimestamp)) break;
                      if (!targetAtOrAfter) r = i - 1;
                      else l = i + 1;
                  }
              }
              /// @notice Fetches the observations beforeOrAt and atOrAfter a given target, i.e. where [beforeOrAt, atOrAfter] is satisfied
              /// @dev Assumes there is at least 1 initialized observation.
              /// Used by observeSingle() to compute the counterfactual accumulator values as of a given block timestamp.
              /// @param self The stored oracle array
              /// @param time The current block.timestamp
              /// @param target The timestamp at which the reserved observation should be for
              /// @param tick The active tick at the time of the returned or simulated observation
              /// @param index The index of the observation that was most recently written to the observations array
              /// @param liquidity The total pool liquidity at the time of the call
              /// @param cardinality The number of populated elements in the oracle array
              /// @return beforeOrAt The observation which occurred at, or before, the given timestamp
              /// @return atOrAfter The observation which occurred at, or after, the given timestamp
              function getSurroundingObservations(
                  Observation[65535] storage self,
                  uint32 time,
                  uint32 target,
                  int24 tick,
                  uint16 index,
                  uint128 liquidity,
                  uint16 cardinality
              ) private view returns (Observation memory beforeOrAt, Observation memory atOrAfter) {
                  // optimistically set before to the newest observation
                  beforeOrAt = self[index];
                  // if the target is chronologically at or after the newest observation, we can early return
                  if (lte(time, beforeOrAt.blockTimestamp, target)) {
                      if (beforeOrAt.blockTimestamp == target) {
                          // if newest observation equals target, we're in the same block, so we can ignore atOrAfter
                          return (beforeOrAt, atOrAfter);
                      } else {
                          // otherwise, we need to transform
                          return (beforeOrAt, transform(beforeOrAt, target, tick, liquidity));
                      }
                  }
                  // now, set before to the oldest observation
                  beforeOrAt = self[(index + 1) % cardinality];
                  if (!beforeOrAt.initialized) beforeOrAt = self[0];
                  // ensure that the target is chronologically at or after the oldest observation
                  require(lte(time, beforeOrAt.blockTimestamp, target), 'OLD');
                  // if we've reached this point, we have to binary search
                  return binarySearch(self, time, target, index, cardinality);
              }
              /// @dev Reverts if an observation at or before the desired observation timestamp does not exist.
              /// 0 may be passed as `secondsAgo' to return the current cumulative values.
              /// If called with a timestamp falling between two observations, returns the counterfactual accumulator values
              /// at exactly the timestamp between the two observations.
              /// @param self The stored oracle array
              /// @param time The current block timestamp
              /// @param secondsAgo The amount of time to look back, in seconds, at which point to return an observation
              /// @param tick The current tick
              /// @param index The index of the observation that was most recently written to the observations array
              /// @param liquidity The current in-range pool liquidity
              /// @param cardinality The number of populated elements in the oracle array
              /// @return tickCumulative The tick * time elapsed since the pool was first initialized, as of `secondsAgo`
              /// @return secondsPerLiquidityCumulativeX128 The time elapsed / max(1, liquidity) since the pool was first initialized, as of `secondsAgo`
              function observeSingle(
                  Observation[65535] storage self,
                  uint32 time,
                  uint32 secondsAgo,
                  int24 tick,
                  uint16 index,
                  uint128 liquidity,
                  uint16 cardinality
              ) internal view returns (int56 tickCumulative, uint160 secondsPerLiquidityCumulativeX128) {
                  if (secondsAgo == 0) {
                      Observation memory last = self[index];
                      if (last.blockTimestamp != time) last = transform(last, time, tick, liquidity);
                      return (last.tickCumulative, last.secondsPerLiquidityCumulativeX128);
                  }
                  uint32 target = time - secondsAgo;
                  (Observation memory beforeOrAt, Observation memory atOrAfter) =
                      getSurroundingObservations(self, time, target, tick, index, liquidity, cardinality);
                  if (target == beforeOrAt.blockTimestamp) {
                      // we're at the left boundary
                      return (beforeOrAt.tickCumulative, beforeOrAt.secondsPerLiquidityCumulativeX128);
                  } else if (target == atOrAfter.blockTimestamp) {
                      // we're at the right boundary
                      return (atOrAfter.tickCumulative, atOrAfter.secondsPerLiquidityCumulativeX128);
                  } else {
                      // we're in the middle
                      uint32 observationTimeDelta = atOrAfter.blockTimestamp - beforeOrAt.blockTimestamp;
                      uint32 targetDelta = target - beforeOrAt.blockTimestamp;
                      return (
                          beforeOrAt.tickCumulative +
                              ((atOrAfter.tickCumulative - beforeOrAt.tickCumulative) / observationTimeDelta) *
                              targetDelta,
                          beforeOrAt.secondsPerLiquidityCumulativeX128 +
                              uint160(
                                  (uint256(
                                      atOrAfter.secondsPerLiquidityCumulativeX128 - beforeOrAt.secondsPerLiquidityCumulativeX128
                                  ) * targetDelta) / observationTimeDelta
                              )
                      );
                  }
              }
              /// @notice Returns the accumulator values as of each time seconds ago from the given time in the array of `secondsAgos`
              /// @dev Reverts if `secondsAgos` > oldest observation
              /// @param self The stored oracle array
              /// @param time The current block.timestamp
              /// @param secondsAgos Each amount of time to look back, in seconds, at which point to return an observation
              /// @param tick The current tick
              /// @param index The index of the observation that was most recently written to the observations array
              /// @param liquidity The current in-range pool liquidity
              /// @param cardinality The number of populated elements in the oracle array
              /// @return tickCumulatives The tick * time elapsed since the pool was first initialized, as of each `secondsAgo`
              /// @return secondsPerLiquidityCumulativeX128s The cumulative seconds / max(1, liquidity) since the pool was first initialized, as of each `secondsAgo`
              function observe(
                  Observation[65535] storage self,
                  uint32 time,
                  uint32[] memory secondsAgos,
                  int24 tick,
                  uint16 index,
                  uint128 liquidity,
                  uint16 cardinality
              ) internal view returns (int56[] memory tickCumulatives, uint160[] memory secondsPerLiquidityCumulativeX128s) {
                  require(cardinality > 0, 'I');
                  tickCumulatives = new int56[](secondsAgos.length);
                  secondsPerLiquidityCumulativeX128s = new uint160[](secondsAgos.length);
                  for (uint256 i = 0; i < secondsAgos.length; i++) {
                      (tickCumulatives[i], secondsPerLiquidityCumulativeX128s[i]) = observeSingle(
                          self,
                          time,
                          secondsAgos[i],
                          tick,
                          index,
                          liquidity,
                          cardinality
                      );
                  }
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.4.0;
          /// @title Contains 512-bit math functions
          /// @notice Facilitates multiplication and division that can have overflow of an intermediate value without any loss of precision
          /// @dev Handles "phantom overflow" i.e., allows multiplication and division where an intermediate value overflows 256 bits
          library FullMath {
              /// @notice Calculates floor(a×b÷denominator) with full precision. Throws if result overflows a uint256 or denominator == 0
              /// @param a The multiplicand
              /// @param b The multiplier
              /// @param denominator The divisor
              /// @return result The 256-bit result
              /// @dev Credit to Remco Bloemen under MIT license https://xn--2-umb.com/21/muldiv
              function mulDiv(
                  uint256 a,
                  uint256 b,
                  uint256 denominator
              ) internal pure returns (uint256 result) {
                  // 512-bit multiply [prod1 prod0] = a * b
                  // Compute the product mod 2**256 and mod 2**256 - 1
                  // then use the Chinese Remainder Theorem to reconstruct
                  // the 512 bit result. The result is stored in two 256
                  // variables such that product = prod1 * 2**256 + prod0
                  uint256 prod0; // Least significant 256 bits of the product
                  uint256 prod1; // Most significant 256 bits of the product
                  assembly {
                      let mm := mulmod(a, b, not(0))
                      prod0 := mul(a, b)
                      prod1 := sub(sub(mm, prod0), lt(mm, prod0))
                  }
                  // Handle non-overflow cases, 256 by 256 division
                  if (prod1 == 0) {
                      require(denominator > 0);
                      assembly {
                          result := div(prod0, denominator)
                      }
                      return result;
                  }
                  // Make sure the result is less than 2**256.
                  // Also prevents denominator == 0
                  require(denominator > prod1);
                  ///////////////////////////////////////////////
                  // 512 by 256 division.
                  ///////////////////////////////////////////////
                  // Make division exact by subtracting the remainder from [prod1 prod0]
                  // Compute remainder using mulmod
                  uint256 remainder;
                  assembly {
                      remainder := mulmod(a, b, denominator)
                  }
                  // Subtract 256 bit number from 512 bit number
                  assembly {
                      prod1 := sub(prod1, gt(remainder, prod0))
                      prod0 := sub(prod0, remainder)
                  }
                  // Factor powers of two out of denominator
                  // Compute largest power of two divisor of denominator.
                  // Always >= 1.
                  uint256 twos = -denominator & denominator;
                  // Divide denominator by power of two
                  assembly {
                      denominator := div(denominator, twos)
                  }
                  // Divide [prod1 prod0] by the factors of two
                  assembly {
                      prod0 := div(prod0, twos)
                  }
                  // Shift in bits from prod1 into prod0. For this we need
                  // to flip `twos` such that it is 2**256 / twos.
                  // If twos is zero, then it becomes one
                  assembly {
                      twos := add(div(sub(0, twos), twos), 1)
                  }
                  prod0 |= prod1 * twos;
                  // Invert denominator mod 2**256
                  // Now that denominator is an odd number, it has an inverse
                  // modulo 2**256 such that denominator * inv = 1 mod 2**256.
                  // Compute the inverse by starting with a seed that is correct
                  // correct for four bits. That is, denominator * inv = 1 mod 2**4
                  uint256 inv = (3 * denominator) ^ 2;
                  // Now use Newton-Raphson iteration to improve the precision.
                  // Thanks to Hensel's lifting lemma, this also works in modular
                  // arithmetic, doubling the correct bits in each step.
                  inv *= 2 - denominator * inv; // inverse mod 2**8
                  inv *= 2 - denominator * inv; // inverse mod 2**16
                  inv *= 2 - denominator * inv; // inverse mod 2**32
                  inv *= 2 - denominator * inv; // inverse mod 2**64
                  inv *= 2 - denominator * inv; // inverse mod 2**128
                  inv *= 2 - denominator * inv; // inverse mod 2**256
                  // Because the division is now exact we can divide by multiplying
                  // with the modular inverse of denominator. This will give us the
                  // correct result modulo 2**256. Since the precoditions guarantee
                  // that the outcome is less than 2**256, this is the final result.
                  // We don't need to compute the high bits of the result and prod1
                  // is no longer required.
                  result = prod0 * inv;
                  return result;
              }
              /// @notice Calculates ceil(a×b÷denominator) with full precision. Throws if result overflows a uint256 or denominator == 0
              /// @param a The multiplicand
              /// @param b The multiplier
              /// @param denominator The divisor
              /// @return result The 256-bit result
              function mulDivRoundingUp(
                  uint256 a,
                  uint256 b,
                  uint256 denominator
              ) internal pure returns (uint256 result) {
                  result = mulDiv(a, b, denominator);
                  if (mulmod(a, b, denominator) > 0) {
                      require(result < type(uint256).max);
                      result++;
                  }
              }
          }
          // SPDX-License-Identifier: GPL-2.0-or-later
          pragma solidity >=0.4.0;
          /// @title FixedPoint128
          /// @notice A library for handling binary fixed point numbers, see https://en.wikipedia.org/wiki/Q_(number_format)
          library FixedPoint128 {
              uint256 internal constant Q128 = 0x100000000000000000000000000000000;
          }
          // SPDX-License-Identifier: GPL-2.0-or-later
          pragma solidity >=0.6.0;
          import '../interfaces/IERC20Minimal.sol';
          /// @title TransferHelper
          /// @notice Contains helper methods for interacting with ERC20 tokens that do not consistently return true/false
          library TransferHelper {
              /// @notice Transfers tokens from msg.sender to a recipient
              /// @dev Calls transfer on token contract, errors with TF if transfer fails
              /// @param token The contract address of the token which will be transferred
              /// @param to The recipient of the transfer
              /// @param value The value of the transfer
              function safeTransfer(
                  address token,
                  address to,
                  uint256 value
              ) internal {
                  (bool success, bytes memory data) =
                      token.call(abi.encodeWithSelector(IERC20Minimal.transfer.selector, to, value));
                  require(success && (data.length == 0 || abi.decode(data, (bool))), 'TF');
              }
          }
          // SPDX-License-Identifier: GPL-2.0-or-later
          pragma solidity >=0.5.0;
          /// @title Math library for computing sqrt prices from ticks and vice versa
          /// @notice Computes sqrt price for ticks of size 1.0001, i.e. sqrt(1.0001^tick) as fixed point Q64.96 numbers. Supports
          /// prices between 2**-128 and 2**128
          library TickMath {
              /// @dev The minimum tick that may be passed to #getSqrtRatioAtTick computed from log base 1.0001 of 2**-128
              int24 internal constant MIN_TICK = -887272;
              /// @dev The maximum tick that may be passed to #getSqrtRatioAtTick computed from log base 1.0001 of 2**128
              int24 internal constant MAX_TICK = -MIN_TICK;
              /// @dev The minimum value that can be returned from #getSqrtRatioAtTick. Equivalent to getSqrtRatioAtTick(MIN_TICK)
              uint160 internal constant MIN_SQRT_RATIO = 4295128739;
              /// @dev The maximum value that can be returned from #getSqrtRatioAtTick. Equivalent to getSqrtRatioAtTick(MAX_TICK)
              uint160 internal constant MAX_SQRT_RATIO = 1461446703485210103287273052203988822378723970342;
              /// @notice Calculates sqrt(1.0001^tick) * 2^96
              /// @dev Throws if |tick| > max tick
              /// @param tick The input tick for the above formula
              /// @return sqrtPriceX96 A Fixed point Q64.96 number representing the sqrt of the ratio of the two assets (token1/token0)
              /// at the given tick
              function getSqrtRatioAtTick(int24 tick) internal pure returns (uint160 sqrtPriceX96) {
                  uint256 absTick = tick < 0 ? uint256(-int256(tick)) : uint256(int256(tick));
                  require(absTick <= uint256(MAX_TICK), 'T');
                  uint256 ratio = absTick & 0x1 != 0 ? 0xfffcb933bd6fad37aa2d162d1a594001 : 0x100000000000000000000000000000000;
                  if (absTick & 0x2 != 0) ratio = (ratio * 0xfff97272373d413259a46990580e213a) >> 128;
                  if (absTick & 0x4 != 0) ratio = (ratio * 0xfff2e50f5f656932ef12357cf3c7fdcc) >> 128;
                  if (absTick & 0x8 != 0) ratio = (ratio * 0xffe5caca7e10e4e61c3624eaa0941cd0) >> 128;
                  if (absTick & 0x10 != 0) ratio = (ratio * 0xffcb9843d60f6159c9db58835c926644) >> 128;
                  if (absTick & 0x20 != 0) ratio = (ratio * 0xff973b41fa98c081472e6896dfb254c0) >> 128;
                  if (absTick & 0x40 != 0) ratio = (ratio * 0xff2ea16466c96a3843ec78b326b52861) >> 128;
                  if (absTick & 0x80 != 0) ratio = (ratio * 0xfe5dee046a99a2a811c461f1969c3053) >> 128;
                  if (absTick & 0x100 != 0) ratio = (ratio * 0xfcbe86c7900a88aedcffc83b479aa3a4) >> 128;
                  if (absTick & 0x200 != 0) ratio = (ratio * 0xf987a7253ac413176f2b074cf7815e54) >> 128;
                  if (absTick & 0x400 != 0) ratio = (ratio * 0xf3392b0822b70005940c7a398e4b70f3) >> 128;
                  if (absTick & 0x800 != 0) ratio = (ratio * 0xe7159475a2c29b7443b29c7fa6e889d9) >> 128;
                  if (absTick & 0x1000 != 0) ratio = (ratio * 0xd097f3bdfd2022b8845ad8f792aa5825) >> 128;
                  if (absTick & 0x2000 != 0) ratio = (ratio * 0xa9f746462d870fdf8a65dc1f90e061e5) >> 128;
                  if (absTick & 0x4000 != 0) ratio = (ratio * 0x70d869a156d2a1b890bb3df62baf32f7) >> 128;
                  if (absTick & 0x8000 != 0) ratio = (ratio * 0x31be135f97d08fd981231505542fcfa6) >> 128;
                  if (absTick & 0x10000 != 0) ratio = (ratio * 0x9aa508b5b7a84e1c677de54f3e99bc9) >> 128;
                  if (absTick & 0x20000 != 0) ratio = (ratio * 0x5d6af8dedb81196699c329225ee604) >> 128;
                  if (absTick & 0x40000 != 0) ratio = (ratio * 0x2216e584f5fa1ea926041bedfe98) >> 128;
                  if (absTick & 0x80000 != 0) ratio = (ratio * 0x48a170391f7dc42444e8fa2) >> 128;
                  if (tick > 0) ratio = type(uint256).max / ratio;
                  // this divides by 1<<32 rounding up to go from a Q128.128 to a Q128.96.
                  // we then downcast because we know the result always fits within 160 bits due to our tick input constraint
                  // we round up in the division so getTickAtSqrtRatio of the output price is always consistent
                  sqrtPriceX96 = uint160((ratio >> 32) + (ratio % (1 << 32) == 0 ? 0 : 1));
              }
              /// @notice Calculates the greatest tick value such that getRatioAtTick(tick) <= ratio
              /// @dev Throws in case sqrtPriceX96 < MIN_SQRT_RATIO, as MIN_SQRT_RATIO is the lowest value getRatioAtTick may
              /// ever return.
              /// @param sqrtPriceX96 The sqrt ratio for which to compute the tick as a Q64.96
              /// @return tick The greatest tick for which the ratio is less than or equal to the input ratio
              function getTickAtSqrtRatio(uint160 sqrtPriceX96) internal pure returns (int24 tick) {
                  // second inequality must be < because the price can never reach the price at the max tick
                  require(sqrtPriceX96 >= MIN_SQRT_RATIO && sqrtPriceX96 < MAX_SQRT_RATIO, 'R');
                  uint256 ratio = uint256(sqrtPriceX96) << 32;
                  uint256 r = ratio;
                  uint256 msb = 0;
                  assembly {
                      let f := shl(7, gt(r, 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF))
                      msb := or(msb, f)
                      r := shr(f, r)
                  }
                  assembly {
                      let f := shl(6, gt(r, 0xFFFFFFFFFFFFFFFF))
                      msb := or(msb, f)
                      r := shr(f, r)
                  }
                  assembly {
                      let f := shl(5, gt(r, 0xFFFFFFFF))
                      msb := or(msb, f)
                      r := shr(f, r)
                  }
                  assembly {
                      let f := shl(4, gt(r, 0xFFFF))
                      msb := or(msb, f)
                      r := shr(f, r)
                  }
                  assembly {
                      let f := shl(3, gt(r, 0xFF))
                      msb := or(msb, f)
                      r := shr(f, r)
                  }
                  assembly {
                      let f := shl(2, gt(r, 0xF))
                      msb := or(msb, f)
                      r := shr(f, r)
                  }
                  assembly {
                      let f := shl(1, gt(r, 0x3))
                      msb := or(msb, f)
                      r := shr(f, r)
                  }
                  assembly {
                      let f := gt(r, 0x1)
                      msb := or(msb, f)
                  }
                  if (msb >= 128) r = ratio >> (msb - 127);
                  else r = ratio << (127 - msb);
                  int256 log_2 = (int256(msb) - 128) << 64;
                  assembly {
                      r := shr(127, mul(r, r))
                      let f := shr(128, r)
                      log_2 := or(log_2, shl(63, f))
                      r := shr(f, r)
                  }
                  assembly {
                      r := shr(127, mul(r, r))
                      let f := shr(128, r)
                      log_2 := or(log_2, shl(62, f))
                      r := shr(f, r)
                  }
                  assembly {
                      r := shr(127, mul(r, r))
                      let f := shr(128, r)
                      log_2 := or(log_2, shl(61, f))
                      r := shr(f, r)
                  }
                  assembly {
                      r := shr(127, mul(r, r))
                      let f := shr(128, r)
                      log_2 := or(log_2, shl(60, f))
                      r := shr(f, r)
                  }
                  assembly {
                      r := shr(127, mul(r, r))
                      let f := shr(128, r)
                      log_2 := or(log_2, shl(59, f))
                      r := shr(f, r)
                  }
                  assembly {
                      r := shr(127, mul(r, r))
                      let f := shr(128, r)
                      log_2 := or(log_2, shl(58, f))
                      r := shr(f, r)
                  }
                  assembly {
                      r := shr(127, mul(r, r))
                      let f := shr(128, r)
                      log_2 := or(log_2, shl(57, f))
                      r := shr(f, r)
                  }
                  assembly {
                      r := shr(127, mul(r, r))
                      let f := shr(128, r)
                      log_2 := or(log_2, shl(56, f))
                      r := shr(f, r)
                  }
                  assembly {
                      r := shr(127, mul(r, r))
                      let f := shr(128, r)
                      log_2 := or(log_2, shl(55, f))
                      r := shr(f, r)
                  }
                  assembly {
                      r := shr(127, mul(r, r))
                      let f := shr(128, r)
                      log_2 := or(log_2, shl(54, f))
                      r := shr(f, r)
                  }
                  assembly {
                      r := shr(127, mul(r, r))
                      let f := shr(128, r)
                      log_2 := or(log_2, shl(53, f))
                      r := shr(f, r)
                  }
                  assembly {
                      r := shr(127, mul(r, r))
                      let f := shr(128, r)
                      log_2 := or(log_2, shl(52, f))
                      r := shr(f, r)
                  }
                  assembly {
                      r := shr(127, mul(r, r))
                      let f := shr(128, r)
                      log_2 := or(log_2, shl(51, f))
                      r := shr(f, r)
                  }
                  assembly {
                      r := shr(127, mul(r, r))
                      let f := shr(128, r)
                      log_2 := or(log_2, shl(50, f))
                  }
                  int256 log_sqrt10001 = log_2 * 255738958999603826347141; // 128.128 number
                  int24 tickLow = int24((log_sqrt10001 - 3402992956809132418596140100660247210) >> 128);
                  int24 tickHi = int24((log_sqrt10001 + 291339464771989622907027621153398088495) >> 128);
                  tick = tickLow == tickHi ? tickLow : getSqrtRatioAtTick(tickHi) <= sqrtPriceX96 ? tickHi : tickLow;
              }
          }
          // SPDX-License-Identifier: GPL-2.0-or-later
          pragma solidity >=0.5.0;
          /// @title Math library for liquidity
          library LiquidityMath {
              /// @notice Add a signed liquidity delta to liquidity and revert if it overflows or underflows
              /// @param x The liquidity before change
              /// @param y The delta by which liquidity should be changed
              /// @return z The liquidity delta
              function addDelta(uint128 x, int128 y) internal pure returns (uint128 z) {
                  if (y < 0) {
                      require((z = x - uint128(-y)) < x, 'LS');
                  } else {
                      require((z = x + uint128(y)) >= x, 'LA');
                  }
              }
          }
          // SPDX-License-Identifier: BUSL-1.1
          pragma solidity >=0.5.0;
          import './LowGasSafeMath.sol';
          import './SafeCast.sol';
          import './FullMath.sol';
          import './UnsafeMath.sol';
          import './FixedPoint96.sol';
          /// @title Functions based on Q64.96 sqrt price and liquidity
          /// @notice Contains the math that uses square root of price as a Q64.96 and liquidity to compute deltas
          library SqrtPriceMath {
              using LowGasSafeMath for uint256;
              using SafeCast for uint256;
              /// @notice Gets the next sqrt price given a delta of token0
              /// @dev Always rounds up, because in the exact output case (increasing price) we need to move the price at least
              /// far enough to get the desired output amount, and in the exact input case (decreasing price) we need to move the
              /// price less in order to not send too much output.
              /// The most precise formula for this is liquidity * sqrtPX96 / (liquidity +- amount * sqrtPX96),
              /// if this is impossible because of overflow, we calculate liquidity / (liquidity / sqrtPX96 +- amount).
              /// @param sqrtPX96 The starting price, i.e. before accounting for the token0 delta
              /// @param liquidity The amount of usable liquidity
              /// @param amount How much of token0 to add or remove from virtual reserves
              /// @param add Whether to add or remove the amount of token0
              /// @return The price after adding or removing amount, depending on add
              function getNextSqrtPriceFromAmount0RoundingUp(
                  uint160 sqrtPX96,
                  uint128 liquidity,
                  uint256 amount,
                  bool add
              ) internal pure returns (uint160) {
                  // we short circuit amount == 0 because the result is otherwise not guaranteed to equal the input price
                  if (amount == 0) return sqrtPX96;
                  uint256 numerator1 = uint256(liquidity) << FixedPoint96.RESOLUTION;
                  if (add) {
                      uint256 product;
                      if ((product = amount * sqrtPX96) / amount == sqrtPX96) {
                          uint256 denominator = numerator1 + product;
                          if (denominator >= numerator1)
                              // always fits in 160 bits
                              return uint160(FullMath.mulDivRoundingUp(numerator1, sqrtPX96, denominator));
                      }
                      return uint160(UnsafeMath.divRoundingUp(numerator1, (numerator1 / sqrtPX96).add(amount)));
                  } else {
                      uint256 product;
                      // if the product overflows, we know the denominator underflows
                      // in addition, we must check that the denominator does not underflow
                      require((product = amount * sqrtPX96) / amount == sqrtPX96 && numerator1 > product);
                      uint256 denominator = numerator1 - product;
                      return FullMath.mulDivRoundingUp(numerator1, sqrtPX96, denominator).toUint160();
                  }
              }
              /// @notice Gets the next sqrt price given a delta of token1
              /// @dev Always rounds down, because in the exact output case (decreasing price) we need to move the price at least
              /// far enough to get the desired output amount, and in the exact input case (increasing price) we need to move the
              /// price less in order to not send too much output.
              /// The formula we compute is within <1 wei of the lossless version: sqrtPX96 +- amount / liquidity
              /// @param sqrtPX96 The starting price, i.e., before accounting for the token1 delta
              /// @param liquidity The amount of usable liquidity
              /// @param amount How much of token1 to add, or remove, from virtual reserves
              /// @param add Whether to add, or remove, the amount of token1
              /// @return The price after adding or removing `amount`
              function getNextSqrtPriceFromAmount1RoundingDown(
                  uint160 sqrtPX96,
                  uint128 liquidity,
                  uint256 amount,
                  bool add
              ) internal pure returns (uint160) {
                  // if we're adding (subtracting), rounding down requires rounding the quotient down (up)
                  // in both cases, avoid a mulDiv for most inputs
                  if (add) {
                      uint256 quotient =
                          (
                              amount <= type(uint160).max
                                  ? (amount << FixedPoint96.RESOLUTION) / liquidity
                                  : FullMath.mulDiv(amount, FixedPoint96.Q96, liquidity)
                          );
                      return uint256(sqrtPX96).add(quotient).toUint160();
                  } else {
                      uint256 quotient =
                          (
                              amount <= type(uint160).max
                                  ? UnsafeMath.divRoundingUp(amount << FixedPoint96.RESOLUTION, liquidity)
                                  : FullMath.mulDivRoundingUp(amount, FixedPoint96.Q96, liquidity)
                          );
                      require(sqrtPX96 > quotient);
                      // always fits 160 bits
                      return uint160(sqrtPX96 - quotient);
                  }
              }
              /// @notice Gets the next sqrt price given an input amount of token0 or token1
              /// @dev Throws if price or liquidity are 0, or if the next price is out of bounds
              /// @param sqrtPX96 The starting price, i.e., before accounting for the input amount
              /// @param liquidity The amount of usable liquidity
              /// @param amountIn How much of token0, or token1, is being swapped in
              /// @param zeroForOne Whether the amount in is token0 or token1
              /// @return sqrtQX96 The price after adding the input amount to token0 or token1
              function getNextSqrtPriceFromInput(
                  uint160 sqrtPX96,
                  uint128 liquidity,
                  uint256 amountIn,
                  bool zeroForOne
              ) internal pure returns (uint160 sqrtQX96) {
                  require(sqrtPX96 > 0);
                  require(liquidity > 0);
                  // round to make sure that we don't pass the target price
                  return
                      zeroForOne
                          ? getNextSqrtPriceFromAmount0RoundingUp(sqrtPX96, liquidity, amountIn, true)
                          : getNextSqrtPriceFromAmount1RoundingDown(sqrtPX96, liquidity, amountIn, true);
              }
              /// @notice Gets the next sqrt price given an output amount of token0 or token1
              /// @dev Throws if price or liquidity are 0 or the next price is out of bounds
              /// @param sqrtPX96 The starting price before accounting for the output amount
              /// @param liquidity The amount of usable liquidity
              /// @param amountOut How much of token0, or token1, is being swapped out
              /// @param zeroForOne Whether the amount out is token0 or token1
              /// @return sqrtQX96 The price after removing the output amount of token0 or token1
              function getNextSqrtPriceFromOutput(
                  uint160 sqrtPX96,
                  uint128 liquidity,
                  uint256 amountOut,
                  bool zeroForOne
              ) internal pure returns (uint160 sqrtQX96) {
                  require(sqrtPX96 > 0);
                  require(liquidity > 0);
                  // round to make sure that we pass the target price
                  return
                      zeroForOne
                          ? getNextSqrtPriceFromAmount1RoundingDown(sqrtPX96, liquidity, amountOut, false)
                          : getNextSqrtPriceFromAmount0RoundingUp(sqrtPX96, liquidity, amountOut, false);
              }
              /// @notice Gets the amount0 delta between two prices
              /// @dev Calculates liquidity / sqrt(lower) - liquidity / sqrt(upper),
              /// i.e. liquidity * (sqrt(upper) - sqrt(lower)) / (sqrt(upper) * sqrt(lower))
              /// @param sqrtRatioAX96 A sqrt price
              /// @param sqrtRatioBX96 Another sqrt price
              /// @param liquidity The amount of usable liquidity
              /// @param roundUp Whether to round the amount up or down
              /// @return amount0 Amount of token0 required to cover a position of size liquidity between the two passed prices
              function getAmount0Delta(
                  uint160 sqrtRatioAX96,
                  uint160 sqrtRatioBX96,
                  uint128 liquidity,
                  bool roundUp
              ) internal pure returns (uint256 amount0) {
                  if (sqrtRatioAX96 > sqrtRatioBX96) (sqrtRatioAX96, sqrtRatioBX96) = (sqrtRatioBX96, sqrtRatioAX96);
                  uint256 numerator1 = uint256(liquidity) << FixedPoint96.RESOLUTION;
                  uint256 numerator2 = sqrtRatioBX96 - sqrtRatioAX96;
                  require(sqrtRatioAX96 > 0);
                  return
                      roundUp
                          ? UnsafeMath.divRoundingUp(
                              FullMath.mulDivRoundingUp(numerator1, numerator2, sqrtRatioBX96),
                              sqrtRatioAX96
                          )
                          : FullMath.mulDiv(numerator1, numerator2, sqrtRatioBX96) / sqrtRatioAX96;
              }
              /// @notice Gets the amount1 delta between two prices
              /// @dev Calculates liquidity * (sqrt(upper) - sqrt(lower))
              /// @param sqrtRatioAX96 A sqrt price
              /// @param sqrtRatioBX96 Another sqrt price
              /// @param liquidity The amount of usable liquidity
              /// @param roundUp Whether to round the amount up, or down
              /// @return amount1 Amount of token1 required to cover a position of size liquidity between the two passed prices
              function getAmount1Delta(
                  uint160 sqrtRatioAX96,
                  uint160 sqrtRatioBX96,
                  uint128 liquidity,
                  bool roundUp
              ) internal pure returns (uint256 amount1) {
                  if (sqrtRatioAX96 > sqrtRatioBX96) (sqrtRatioAX96, sqrtRatioBX96) = (sqrtRatioBX96, sqrtRatioAX96);
                  return
                      roundUp
                          ? FullMath.mulDivRoundingUp(liquidity, sqrtRatioBX96 - sqrtRatioAX96, FixedPoint96.Q96)
                          : FullMath.mulDiv(liquidity, sqrtRatioBX96 - sqrtRatioAX96, FixedPoint96.Q96);
              }
              /// @notice Helper that gets signed token0 delta
              /// @param sqrtRatioAX96 A sqrt price
              /// @param sqrtRatioBX96 Another sqrt price
              /// @param liquidity The change in liquidity for which to compute the amount0 delta
              /// @return amount0 Amount of token0 corresponding to the passed liquidityDelta between the two prices
              function getAmount0Delta(
                  uint160 sqrtRatioAX96,
                  uint160 sqrtRatioBX96,
                  int128 liquidity
              ) internal pure returns (int256 amount0) {
                  return
                      liquidity < 0
                          ? -getAmount0Delta(sqrtRatioAX96, sqrtRatioBX96, uint128(-liquidity), false).toInt256()
                          : getAmount0Delta(sqrtRatioAX96, sqrtRatioBX96, uint128(liquidity), true).toInt256();
              }
              /// @notice Helper that gets signed token1 delta
              /// @param sqrtRatioAX96 A sqrt price
              /// @param sqrtRatioBX96 Another sqrt price
              /// @param liquidity The change in liquidity for which to compute the amount1 delta
              /// @return amount1 Amount of token1 corresponding to the passed liquidityDelta between the two prices
              function getAmount1Delta(
                  uint160 sqrtRatioAX96,
                  uint160 sqrtRatioBX96,
                  int128 liquidity
              ) internal pure returns (int256 amount1) {
                  return
                      liquidity < 0
                          ? -getAmount1Delta(sqrtRatioAX96, sqrtRatioBX96, uint128(-liquidity), false).toInt256()
                          : getAmount1Delta(sqrtRatioAX96, sqrtRatioBX96, uint128(liquidity), true).toInt256();
              }
          }
          // SPDX-License-Identifier: BUSL-1.1
          pragma solidity >=0.5.0;
          import './FullMath.sol';
          import './SqrtPriceMath.sol';
          /// @title Computes the result of a swap within ticks
          /// @notice Contains methods for computing the result of a swap within a single tick price range, i.e., a single tick.
          library SwapMath {
              /// @notice Computes the result of swapping some amount in, or amount out, given the parameters of the swap
              /// @dev The fee, plus the amount in, will never exceed the amount remaining if the swap's `amountSpecified` is positive
              /// @param sqrtRatioCurrentX96 The current sqrt price of the pool
              /// @param sqrtRatioTargetX96 The price that cannot be exceeded, from which the direction of the swap is inferred
              /// @param liquidity The usable liquidity
              /// @param amountRemaining How much input or output amount is remaining to be swapped in/out
              /// @param feePips The fee taken from the input amount, expressed in hundredths of a bip
              /// @return sqrtRatioNextX96 The price after swapping the amount in/out, not to exceed the price target
              /// @return amountIn The amount to be swapped in, of either token0 or token1, based on the direction of the swap
              /// @return amountOut The amount to be received, of either token0 or token1, based on the direction of the swap
              /// @return feeAmount The amount of input that will be taken as a fee
              function computeSwapStep(
                  uint160 sqrtRatioCurrentX96,
                  uint160 sqrtRatioTargetX96,
                  uint128 liquidity,
                  int256 amountRemaining,
                  uint24 feePips
              )
                  internal
                  pure
                  returns (
                      uint160 sqrtRatioNextX96,
                      uint256 amountIn,
                      uint256 amountOut,
                      uint256 feeAmount
                  )
              {
                  bool zeroForOne = sqrtRatioCurrentX96 >= sqrtRatioTargetX96;
                  bool exactIn = amountRemaining >= 0;
                  if (exactIn) {
                      uint256 amountRemainingLessFee = FullMath.mulDiv(uint256(amountRemaining), 1e6 - feePips, 1e6);
                      amountIn = zeroForOne
                          ? SqrtPriceMath.getAmount0Delta(sqrtRatioTargetX96, sqrtRatioCurrentX96, liquidity, true)
                          : SqrtPriceMath.getAmount1Delta(sqrtRatioCurrentX96, sqrtRatioTargetX96, liquidity, true);
                      if (amountRemainingLessFee >= amountIn) sqrtRatioNextX96 = sqrtRatioTargetX96;
                      else
                          sqrtRatioNextX96 = SqrtPriceMath.getNextSqrtPriceFromInput(
                              sqrtRatioCurrentX96,
                              liquidity,
                              amountRemainingLessFee,
                              zeroForOne
                          );
                  } else {
                      amountOut = zeroForOne
                          ? SqrtPriceMath.getAmount1Delta(sqrtRatioTargetX96, sqrtRatioCurrentX96, liquidity, false)
                          : SqrtPriceMath.getAmount0Delta(sqrtRatioCurrentX96, sqrtRatioTargetX96, liquidity, false);
                      if (uint256(-amountRemaining) >= amountOut) sqrtRatioNextX96 = sqrtRatioTargetX96;
                      else
                          sqrtRatioNextX96 = SqrtPriceMath.getNextSqrtPriceFromOutput(
                              sqrtRatioCurrentX96,
                              liquidity,
                              uint256(-amountRemaining),
                              zeroForOne
                          );
                  }
                  bool max = sqrtRatioTargetX96 == sqrtRatioNextX96;
                  // get the input/output amounts
                  if (zeroForOne) {
                      amountIn = max && exactIn
                          ? amountIn
                          : SqrtPriceMath.getAmount0Delta(sqrtRatioNextX96, sqrtRatioCurrentX96, liquidity, true);
                      amountOut = max && !exactIn
                          ? amountOut
                          : SqrtPriceMath.getAmount1Delta(sqrtRatioNextX96, sqrtRatioCurrentX96, liquidity, false);
                  } else {
                      amountIn = max && exactIn
                          ? amountIn
                          : SqrtPriceMath.getAmount1Delta(sqrtRatioCurrentX96, sqrtRatioNextX96, liquidity, true);
                      amountOut = max && !exactIn
                          ? amountOut
                          : SqrtPriceMath.getAmount0Delta(sqrtRatioCurrentX96, sqrtRatioNextX96, liquidity, false);
                  }
                  // cap the output amount to not exceed the remaining output amount
                  if (!exactIn && amountOut > uint256(-amountRemaining)) {
                      amountOut = uint256(-amountRemaining);
                  }
                  if (exactIn && sqrtRatioNextX96 != sqrtRatioTargetX96) {
                      // we didn't reach the target, so take the remainder of the maximum input as fee
                      feeAmount = uint256(amountRemaining) - amountIn;
                  } else {
                      feeAmount = FullMath.mulDivRoundingUp(amountIn, feePips, 1e6 - feePips);
                  }
              }
          }
          // SPDX-License-Identifier: GPL-2.0-or-later
          pragma solidity >=0.5.0;
          /// @title An interface for a contract that is capable of deploying Uniswap V3 Pools
          /// @notice A contract that constructs a pool must implement this to pass arguments to the pool
          /// @dev This is used to avoid having constructor arguments in the pool contract, which results in the init code hash
          /// of the pool being constant allowing the CREATE2 address of the pool to be cheaply computed on-chain
          interface IUniswapV3PoolDeployer {
              /// @notice Get the parameters to be used in constructing the pool, set transiently during pool creation.
              /// @dev Called by the pool constructor to fetch the parameters of the pool
              /// Returns factory The factory address
              /// Returns token0 The first token of the pool by address sort order
              /// Returns token1 The second token of the pool by address sort order
              /// Returns fee The fee collected upon every swap in the pool, denominated in hundredths of a bip
              /// Returns tickSpacing The minimum number of ticks between initialized ticks
              function parameters()
                  external
                  view
                  returns (
                      address factory,
                      address token0,
                      address token1,
                      uint24 fee,
                      int24 tickSpacing
                  );
          }
          // SPDX-License-Identifier: GPL-2.0-or-later
          pragma solidity >=0.5.0;
          /// @title The interface for the Uniswap V3 Factory
          /// @notice The Uniswap V3 Factory facilitates creation of Uniswap V3 pools and control over the protocol fees
          interface IUniswapV3Factory {
              /// @notice Emitted when the owner of the factory is changed
              /// @param oldOwner The owner before the owner was changed
              /// @param newOwner The owner after the owner was changed
              event OwnerChanged(address indexed oldOwner, address indexed newOwner);
              /// @notice Emitted when a pool is created
              /// @param token0 The first token of the pool by address sort order
              /// @param token1 The second token of the pool by address sort order
              /// @param fee The fee collected upon every swap in the pool, denominated in hundredths of a bip
              /// @param tickSpacing The minimum number of ticks between initialized ticks
              /// @param pool The address of the created pool
              event PoolCreated(
                  address indexed token0,
                  address indexed token1,
                  uint24 indexed fee,
                  int24 tickSpacing,
                  address pool
              );
              /// @notice Emitted when a new fee amount is enabled for pool creation via the factory
              /// @param fee The enabled fee, denominated in hundredths of a bip
              /// @param tickSpacing The minimum number of ticks between initialized ticks for pools created with the given fee
              event FeeAmountEnabled(uint24 indexed fee, int24 indexed tickSpacing);
              /// @notice Returns the current owner of the factory
              /// @dev Can be changed by the current owner via setOwner
              /// @return The address of the factory owner
              function owner() external view returns (address);
              /// @notice Returns the tick spacing for a given fee amount, if enabled, or 0 if not enabled
              /// @dev A fee amount can never be removed, so this value should be hard coded or cached in the calling context
              /// @param fee The enabled fee, denominated in hundredths of a bip. Returns 0 in case of unenabled fee
              /// @return The tick spacing
              function feeAmountTickSpacing(uint24 fee) external view returns (int24);
              /// @notice Returns the pool address for a given pair of tokens and a fee, or address 0 if it does not exist
              /// @dev tokenA and tokenB may be passed in either token0/token1 or token1/token0 order
              /// @param tokenA The contract address of either token0 or token1
              /// @param tokenB The contract address of the other token
              /// @param fee The fee collected upon every swap in the pool, denominated in hundredths of a bip
              /// @return pool The pool address
              function getPool(
                  address tokenA,
                  address tokenB,
                  uint24 fee
              ) external view returns (address pool);
              /// @notice Creates a pool for the given two tokens and fee
              /// @param tokenA One of the two tokens in the desired pool
              /// @param tokenB The other of the two tokens in the desired pool
              /// @param fee The desired fee for the pool
              /// @dev tokenA and tokenB may be passed in either order: token0/token1 or token1/token0. tickSpacing is retrieved
              /// from the fee. The call will revert if the pool already exists, the fee is invalid, or the token arguments
              /// are invalid.
              /// @return pool The address of the newly created pool
              function createPool(
                  address tokenA,
                  address tokenB,
                  uint24 fee
              ) external returns (address pool);
              /// @notice Updates the owner of the factory
              /// @dev Must be called by the current owner
              /// @param _owner The new owner of the factory
              function setOwner(address _owner) external;
              /// @notice Enables a fee amount with the given tickSpacing
              /// @dev Fee amounts may never be removed once enabled
              /// @param fee The fee amount to enable, denominated in hundredths of a bip (i.e. 1e-6)
              /// @param tickSpacing The spacing between ticks to be enforced for all pools created with the given fee amount
              function enableFeeAmount(uint24 fee, int24 tickSpacing) external;
          }
          // SPDX-License-Identifier: GPL-2.0-or-later
          pragma solidity >=0.5.0;
          /// @title Minimal ERC20 interface for Uniswap
          /// @notice Contains a subset of the full ERC20 interface that is used in Uniswap V3
          interface IERC20Minimal {
              /// @notice Returns the balance of a token
              /// @param account The account for which to look up the number of tokens it has, i.e. its balance
              /// @return The number of tokens held by the account
              function balanceOf(address account) external view returns (uint256);
              /// @notice Transfers the amount of token from the `msg.sender` to the recipient
              /// @param recipient The account that will receive the amount transferred
              /// @param amount The number of tokens to send from the sender to the recipient
              /// @return Returns true for a successful transfer, false for an unsuccessful transfer
              function transfer(address recipient, uint256 amount) external returns (bool);
              /// @notice Returns the current allowance given to a spender by an owner
              /// @param owner The account of the token owner
              /// @param spender The account of the token spender
              /// @return The current allowance granted by `owner` to `spender`
              function allowance(address owner, address spender) external view returns (uint256);
              /// @notice Sets the allowance of a spender from the `msg.sender` to the value `amount`
              /// @param spender The account which will be allowed to spend a given amount of the owners tokens
              /// @param amount The amount of tokens allowed to be used by `spender`
              /// @return Returns true for a successful approval, false for unsuccessful
              function approve(address spender, uint256 amount) external returns (bool);
              /// @notice Transfers `amount` tokens from `sender` to `recipient` up to the allowance given to the `msg.sender`
              /// @param sender The account from which the transfer will be initiated
              /// @param recipient The recipient of the transfer
              /// @param amount The amount of the transfer
              /// @return Returns true for a successful transfer, false for unsuccessful
              function transferFrom(
                  address sender,
                  address recipient,
                  uint256 amount
              ) external returns (bool);
              /// @notice Event emitted when tokens are transferred from one address to another, either via `#transfer` or `#transferFrom`.
              /// @param from The account from which the tokens were sent, i.e. the balance decreased
              /// @param to The account to which the tokens were sent, i.e. the balance increased
              /// @param value The amount of tokens that were transferred
              event Transfer(address indexed from, address indexed to, uint256 value);
              /// @notice Event emitted when the approval amount for the spender of a given owner's tokens changes.
              /// @param owner The account that approved spending of its tokens
              /// @param spender The account for which the spending allowance was modified
              /// @param value The new allowance from the owner to the spender
              event Approval(address indexed owner, address indexed spender, uint256 value);
          }
          // SPDX-License-Identifier: GPL-2.0-or-later
          pragma solidity >=0.5.0;
          /// @title Callback for IUniswapV3PoolActions#mint
          /// @notice Any contract that calls IUniswapV3PoolActions#mint must implement this interface
          interface IUniswapV3MintCallback {
              /// @notice Called to `msg.sender` after minting liquidity to a position from IUniswapV3Pool#mint.
              /// @dev In the implementation you must pay the pool tokens owed for the minted liquidity.
              /// The caller of this method must be checked to be a UniswapV3Pool deployed by the canonical UniswapV3Factory.
              /// @param amount0Owed The amount of token0 due to the pool for the minted liquidity
              /// @param amount1Owed The amount of token1 due to the pool for the minted liquidity
              /// @param data Any data passed through by the caller via the IUniswapV3PoolActions#mint call
              function uniswapV3MintCallback(
                  uint256 amount0Owed,
                  uint256 amount1Owed,
                  bytes calldata data
              ) external;
          }
          // SPDX-License-Identifier: GPL-2.0-or-later
          pragma solidity >=0.5.0;
          /// @title Callback for IUniswapV3PoolActions#swap
          /// @notice Any contract that calls IUniswapV3PoolActions#swap must implement this interface
          interface IUniswapV3SwapCallback {
              /// @notice Called to `msg.sender` after executing a swap via IUniswapV3Pool#swap.
              /// @dev In the implementation you must pay the pool tokens owed for the swap.
              /// The caller of this method must be checked to be a UniswapV3Pool deployed by the canonical UniswapV3Factory.
              /// amount0Delta and amount1Delta can both be 0 if no tokens were swapped.
              /// @param amount0Delta The amount of token0 that was sent (negative) or must be received (positive) by the pool by
              /// the end of the swap. If positive, the callback must send that amount of token0 to the pool.
              /// @param amount1Delta The amount of token1 that was sent (negative) or must be received (positive) by the pool by
              /// the end of the swap. If positive, the callback must send that amount of token1 to the pool.
              /// @param data Any data passed through by the caller via the IUniswapV3PoolActions#swap call
              function uniswapV3SwapCallback(
                  int256 amount0Delta,
                  int256 amount1Delta,
                  bytes calldata data
              ) external;
          }
          // SPDX-License-Identifier: GPL-2.0-or-later
          pragma solidity >=0.5.0;
          /// @title Callback for IUniswapV3PoolActions#flash
          /// @notice Any contract that calls IUniswapV3PoolActions#flash must implement this interface
          interface IUniswapV3FlashCallback {
              /// @notice Called to `msg.sender` after transferring to the recipient from IUniswapV3Pool#flash.
              /// @dev In the implementation you must repay the pool the tokens sent by flash plus the computed fee amounts.
              /// The caller of this method must be checked to be a UniswapV3Pool deployed by the canonical UniswapV3Factory.
              /// @param fee0 The fee amount in token0 due to the pool by the end of the flash
              /// @param fee1 The fee amount in token1 due to the pool by the end of the flash
              /// @param data Any data passed through by the caller via the IUniswapV3PoolActions#flash call
              function uniswapV3FlashCallback(
                  uint256 fee0,
                  uint256 fee1,
                  bytes calldata data
              ) external;
          }
          // SPDX-License-Identifier: GPL-2.0-or-later
          pragma solidity >=0.5.0;
          /// @title Pool state that never changes
          /// @notice These parameters are fixed for a pool forever, i.e., the methods will always return the same values
          interface IUniswapV3PoolImmutables {
              /// @notice The contract that deployed the pool, which must adhere to the IUniswapV3Factory interface
              /// @return The contract address
              function factory() external view returns (address);
              /// @notice The first of the two tokens of the pool, sorted by address
              /// @return The token contract address
              function token0() external view returns (address);
              /// @notice The second of the two tokens of the pool, sorted by address
              /// @return The token contract address
              function token1() external view returns (address);
              /// @notice The pool's fee in hundredths of a bip, i.e. 1e-6
              /// @return The fee
              function fee() external view returns (uint24);
              /// @notice The pool tick spacing
              /// @dev Ticks can only be used at multiples of this value, minimum of 1 and always positive
              /// e.g.: a tickSpacing of 3 means ticks can be initialized every 3rd tick, i.e., ..., -6, -3, 0, 3, 6, ...
              /// This value is an int24 to avoid casting even though it is always positive.
              /// @return The tick spacing
              function tickSpacing() external view returns (int24);
              /// @notice The maximum amount of position liquidity that can use any tick in the range
              /// @dev This parameter is enforced per tick to prevent liquidity from overflowing a uint128 at any point, and
              /// also prevents out-of-range liquidity from being used to prevent adding in-range liquidity to a pool
              /// @return The max amount of liquidity per tick
              function maxLiquidityPerTick() external view returns (uint128);
          }
          // SPDX-License-Identifier: GPL-2.0-or-later
          pragma solidity >=0.5.0;
          /// @title Pool state that can change
          /// @notice These methods compose the pool's state, and can change with any frequency including multiple times
          /// per transaction
          interface IUniswapV3PoolState {
              /// @notice The 0th storage slot in the pool stores many values, and is exposed as a single method to save gas
              /// when accessed externally.
              /// @return sqrtPriceX96 The current price of the pool as a sqrt(token1/token0) Q64.96 value
              /// tick The current tick of the pool, i.e. according to the last tick transition that was run.
              /// This value may not always be equal to SqrtTickMath.getTickAtSqrtRatio(sqrtPriceX96) if the price is on a tick
              /// boundary.
              /// observationIndex The index of the last oracle observation that was written,
              /// observationCardinality The current maximum number of observations stored in the pool,
              /// observationCardinalityNext The next maximum number of observations, to be updated when the observation.
              /// feeProtocol The protocol fee for both tokens of the pool.
              /// Encoded as two 4 bit values, where the protocol fee of token1 is shifted 4 bits and the protocol fee of token0
              /// is the lower 4 bits. Used as the denominator of a fraction of the swap fee, e.g. 4 means 1/4th of the swap fee.
              /// unlocked Whether the pool is currently locked to reentrancy
              function slot0()
                  external
                  view
                  returns (
                      uint160 sqrtPriceX96,
                      int24 tick,
                      uint16 observationIndex,
                      uint16 observationCardinality,
                      uint16 observationCardinalityNext,
                      uint8 feeProtocol,
                      bool unlocked
                  );
              /// @notice The fee growth as a Q128.128 fees of token0 collected per unit of liquidity for the entire life of the pool
              /// @dev This value can overflow the uint256
              function feeGrowthGlobal0X128() external view returns (uint256);
              /// @notice The fee growth as a Q128.128 fees of token1 collected per unit of liquidity for the entire life of the pool
              /// @dev This value can overflow the uint256
              function feeGrowthGlobal1X128() external view returns (uint256);
              /// @notice The amounts of token0 and token1 that are owed to the protocol
              /// @dev Protocol fees will never exceed uint128 max in either token
              function protocolFees() external view returns (uint128 token0, uint128 token1);
              /// @notice The currently in range liquidity available to the pool
              /// @dev This value has no relationship to the total liquidity across all ticks
              function liquidity() external view returns (uint128);
              /// @notice Look up information about a specific tick in the pool
              /// @param tick The tick to look up
              /// @return liquidityGross the total amount of position liquidity that uses the pool either as tick lower or
              /// tick upper,
              /// liquidityNet how much liquidity changes when the pool price crosses the tick,
              /// feeGrowthOutside0X128 the fee growth on the other side of the tick from the current tick in token0,
              /// feeGrowthOutside1X128 the fee growth on the other side of the tick from the current tick in token1,
              /// tickCumulativeOutside the cumulative tick value on the other side of the tick from the current tick
              /// secondsPerLiquidityOutsideX128 the seconds spent per liquidity on the other side of the tick from the current tick,
              /// secondsOutside the seconds spent on the other side of the tick from the current tick,
              /// initialized Set to true if the tick is initialized, i.e. liquidityGross is greater than 0, otherwise equal to false.
              /// Outside values can only be used if the tick is initialized, i.e. if liquidityGross is greater than 0.
              /// In addition, these values are only relative and must be used only in comparison to previous snapshots for
              /// a specific position.
              function ticks(int24 tick)
                  external
                  view
                  returns (
                      uint128 liquidityGross,
                      int128 liquidityNet,
                      uint256 feeGrowthOutside0X128,
                      uint256 feeGrowthOutside1X128,
                      int56 tickCumulativeOutside,
                      uint160 secondsPerLiquidityOutsideX128,
                      uint32 secondsOutside,
                      bool initialized
                  );
              /// @notice Returns 256 packed tick initialized boolean values. See TickBitmap for more information
              function tickBitmap(int16 wordPosition) external view returns (uint256);
              /// @notice Returns the information about a position by the position's key
              /// @param key The position's key is a hash of a preimage composed by the owner, tickLower and tickUpper
              /// @return _liquidity The amount of liquidity in the position,
              /// Returns feeGrowthInside0LastX128 fee growth of token0 inside the tick range as of the last mint/burn/poke,
              /// Returns feeGrowthInside1LastX128 fee growth of token1 inside the tick range as of the last mint/burn/poke,
              /// Returns tokensOwed0 the computed amount of token0 owed to the position as of the last mint/burn/poke,
              /// Returns tokensOwed1 the computed amount of token1 owed to the position as of the last mint/burn/poke
              function positions(bytes32 key)
                  external
                  view
                  returns (
                      uint128 _liquidity,
                      uint256 feeGrowthInside0LastX128,
                      uint256 feeGrowthInside1LastX128,
                      uint128 tokensOwed0,
                      uint128 tokensOwed1
                  );
              /// @notice Returns data about a specific observation index
              /// @param index The element of the observations array to fetch
              /// @dev You most likely want to use #observe() instead of this method to get an observation as of some amount of time
              /// ago, rather than at a specific index in the array.
              /// @return blockTimestamp The timestamp of the observation,
              /// Returns tickCumulative the tick multiplied by seconds elapsed for the life of the pool as of the observation timestamp,
              /// Returns secondsPerLiquidityCumulativeX128 the seconds per in range liquidity for the life of the pool as of the observation timestamp,
              /// Returns initialized whether the observation has been initialized and the values are safe to use
              function observations(uint256 index)
                  external
                  view
                  returns (
                      uint32 blockTimestamp,
                      int56 tickCumulative,
                      uint160 secondsPerLiquidityCumulativeX128,
                      bool initialized
                  );
          }
          // SPDX-License-Identifier: GPL-2.0-or-later
          pragma solidity >=0.5.0;
          /// @title Pool state that is not stored
          /// @notice Contains view functions to provide information about the pool that is computed rather than stored on the
          /// blockchain. The functions here may have variable gas costs.
          interface IUniswapV3PoolDerivedState {
              /// @notice Returns the cumulative tick and liquidity as of each timestamp `secondsAgo` from the current block timestamp
              /// @dev To get a time weighted average tick or liquidity-in-range, you must call this with two values, one representing
              /// the beginning of the period and another for the end of the period. E.g., to get the last hour time-weighted average tick,
              /// you must call it with secondsAgos = [3600, 0].
              /// @dev The time weighted average tick represents the geometric time weighted average price of the pool, in
              /// log base sqrt(1.0001) of token1 / token0. The TickMath library can be used to go from a tick value to a ratio.
              /// @param secondsAgos From how long ago each cumulative tick and liquidity value should be returned
              /// @return tickCumulatives Cumulative tick values as of each `secondsAgos` from the current block timestamp
              /// @return secondsPerLiquidityCumulativeX128s Cumulative seconds per liquidity-in-range value as of each `secondsAgos` from the current block
              /// timestamp
              function observe(uint32[] calldata secondsAgos)
                  external
                  view
                  returns (int56[] memory tickCumulatives, uint160[] memory secondsPerLiquidityCumulativeX128s);
              /// @notice Returns a snapshot of the tick cumulative, seconds per liquidity and seconds inside a tick range
              /// @dev Snapshots must only be compared to other snapshots, taken over a period for which a position existed.
              /// I.e., snapshots cannot be compared if a position is not held for the entire period between when the first
              /// snapshot is taken and the second snapshot is taken.
              /// @param tickLower The lower tick of the range
              /// @param tickUpper The upper tick of the range
              /// @return tickCumulativeInside The snapshot of the tick accumulator for the range
              /// @return secondsPerLiquidityInsideX128 The snapshot of seconds per liquidity for the range
              /// @return secondsInside The snapshot of seconds per liquidity for the range
              function snapshotCumulativesInside(int24 tickLower, int24 tickUpper)
                  external
                  view
                  returns (
                      int56 tickCumulativeInside,
                      uint160 secondsPerLiquidityInsideX128,
                      uint32 secondsInside
                  );
          }
          // SPDX-License-Identifier: GPL-2.0-or-later
          pragma solidity >=0.5.0;
          /// @title Permissionless pool actions
          /// @notice Contains pool methods that can be called by anyone
          interface IUniswapV3PoolActions {
              /// @notice Sets the initial price for the pool
              /// @dev Price is represented as a sqrt(amountToken1/amountToken0) Q64.96 value
              /// @param sqrtPriceX96 the initial sqrt price of the pool as a Q64.96
              function initialize(uint160 sqrtPriceX96) external;
              /// @notice Adds liquidity for the given recipient/tickLower/tickUpper position
              /// @dev The caller of this method receives a callback in the form of IUniswapV3MintCallback#uniswapV3MintCallback
              /// in which they must pay any token0 or token1 owed for the liquidity. The amount of token0/token1 due depends
              /// on tickLower, tickUpper, the amount of liquidity, and the current price.
              /// @param recipient The address for which the liquidity will be created
              /// @param tickLower The lower tick of the position in which to add liquidity
              /// @param tickUpper The upper tick of the position in which to add liquidity
              /// @param amount The amount of liquidity to mint
              /// @param data Any data that should be passed through to the callback
              /// @return amount0 The amount of token0 that was paid to mint the given amount of liquidity. Matches the value in the callback
              /// @return amount1 The amount of token1 that was paid to mint the given amount of liquidity. Matches the value in the callback
              function mint(
                  address recipient,
                  int24 tickLower,
                  int24 tickUpper,
                  uint128 amount,
                  bytes calldata data
              ) external returns (uint256 amount0, uint256 amount1);
              /// @notice Collects tokens owed to a position
              /// @dev Does not recompute fees earned, which must be done either via mint or burn of any amount of liquidity.
              /// Collect must be called by the position owner. To withdraw only token0 or only token1, amount0Requested or
              /// amount1Requested may be set to zero. To withdraw all tokens owed, caller may pass any value greater than the
              /// actual tokens owed, e.g. type(uint128).max. Tokens owed may be from accumulated swap fees or burned liquidity.
              /// @param recipient The address which should receive the fees collected
              /// @param tickLower The lower tick of the position for which to collect fees
              /// @param tickUpper The upper tick of the position for which to collect fees
              /// @param amount0Requested How much token0 should be withdrawn from the fees owed
              /// @param amount1Requested How much token1 should be withdrawn from the fees owed
              /// @return amount0 The amount of fees collected in token0
              /// @return amount1 The amount of fees collected in token1
              function collect(
                  address recipient,
                  int24 tickLower,
                  int24 tickUpper,
                  uint128 amount0Requested,
                  uint128 amount1Requested
              ) external returns (uint128 amount0, uint128 amount1);
              /// @notice Burn liquidity from the sender and account tokens owed for the liquidity to the position
              /// @dev Can be used to trigger a recalculation of fees owed to a position by calling with an amount of 0
              /// @dev Fees must be collected separately via a call to #collect
              /// @param tickLower The lower tick of the position for which to burn liquidity
              /// @param tickUpper The upper tick of the position for which to burn liquidity
              /// @param amount How much liquidity to burn
              /// @return amount0 The amount of token0 sent to the recipient
              /// @return amount1 The amount of token1 sent to the recipient
              function burn(
                  int24 tickLower,
                  int24 tickUpper,
                  uint128 amount
              ) external returns (uint256 amount0, uint256 amount1);
              /// @notice Swap token0 for token1, or token1 for token0
              /// @dev The caller of this method receives a callback in the form of IUniswapV3SwapCallback#uniswapV3SwapCallback
              /// @param recipient The address to receive the output of the swap
              /// @param zeroForOne The direction of the swap, true for token0 to token1, false for token1 to token0
              /// @param amountSpecified The amount of the swap, which implicitly configures the swap as exact input (positive), or exact output (negative)
              /// @param sqrtPriceLimitX96 The Q64.96 sqrt price limit. If zero for one, the price cannot be less than this
              /// value after the swap. If one for zero, the price cannot be greater than this value after the swap
              /// @param data Any data to be passed through to the callback
              /// @return amount0 The delta of the balance of token0 of the pool, exact when negative, minimum when positive
              /// @return amount1 The delta of the balance of token1 of the pool, exact when negative, minimum when positive
              function swap(
                  address recipient,
                  bool zeroForOne,
                  int256 amountSpecified,
                  uint160 sqrtPriceLimitX96,
                  bytes calldata data
              ) external returns (int256 amount0, int256 amount1);
              /// @notice Receive token0 and/or token1 and pay it back, plus a fee, in the callback
              /// @dev The caller of this method receives a callback in the form of IUniswapV3FlashCallback#uniswapV3FlashCallback
              /// @dev Can be used to donate underlying tokens pro-rata to currently in-range liquidity providers by calling
              /// with 0 amount{0,1} and sending the donation amount(s) from the callback
              /// @param recipient The address which will receive the token0 and token1 amounts
              /// @param amount0 The amount of token0 to send
              /// @param amount1 The amount of token1 to send
              /// @param data Any data to be passed through to the callback
              function flash(
                  address recipient,
                  uint256 amount0,
                  uint256 amount1,
                  bytes calldata data
              ) external;
              /// @notice Increase the maximum number of price and liquidity observations that this pool will store
              /// @dev This method is no-op if the pool already has an observationCardinalityNext greater than or equal to
              /// the input observationCardinalityNext.
              /// @param observationCardinalityNext The desired minimum number of observations for the pool to store
              function increaseObservationCardinalityNext(uint16 observationCardinalityNext) external;
          }
          // SPDX-License-Identifier: GPL-2.0-or-later
          pragma solidity >=0.5.0;
          /// @title Permissioned pool actions
          /// @notice Contains pool methods that may only be called by the factory owner
          interface IUniswapV3PoolOwnerActions {
              /// @notice Set the denominator of the protocol's % share of the fees
              /// @param feeProtocol0 new protocol fee for token0 of the pool
              /// @param feeProtocol1 new protocol fee for token1 of the pool
              function setFeeProtocol(uint8 feeProtocol0, uint8 feeProtocol1) external;
              /// @notice Collect the protocol fee accrued to the pool
              /// @param recipient The address to which collected protocol fees should be sent
              /// @param amount0Requested The maximum amount of token0 to send, can be 0 to collect fees in only token1
              /// @param amount1Requested The maximum amount of token1 to send, can be 0 to collect fees in only token0
              /// @return amount0 The protocol fee collected in token0
              /// @return amount1 The protocol fee collected in token1
              function collectProtocol(
                  address recipient,
                  uint128 amount0Requested,
                  uint128 amount1Requested
              ) external returns (uint128 amount0, uint128 amount1);
          }
          // SPDX-License-Identifier: GPL-2.0-or-later
          pragma solidity >=0.5.0;
          /// @title Events emitted by a pool
          /// @notice Contains all events emitted by the pool
          interface IUniswapV3PoolEvents {
              /// @notice Emitted exactly once by a pool when #initialize is first called on the pool
              /// @dev Mint/Burn/Swap cannot be emitted by the pool before Initialize
              /// @param sqrtPriceX96 The initial sqrt price of the pool, as a Q64.96
              /// @param tick The initial tick of the pool, i.e. log base 1.0001 of the starting price of the pool
              event Initialize(uint160 sqrtPriceX96, int24 tick);
              /// @notice Emitted when liquidity is minted for a given position
              /// @param sender The address that minted the liquidity
              /// @param owner The owner of the position and recipient of any minted liquidity
              /// @param tickLower The lower tick of the position
              /// @param tickUpper The upper tick of the position
              /// @param amount The amount of liquidity minted to the position range
              /// @param amount0 How much token0 was required for the minted liquidity
              /// @param amount1 How much token1 was required for the minted liquidity
              event Mint(
                  address sender,
                  address indexed owner,
                  int24 indexed tickLower,
                  int24 indexed tickUpper,
                  uint128 amount,
                  uint256 amount0,
                  uint256 amount1
              );
              /// @notice Emitted when fees are collected by the owner of a position
              /// @dev Collect events may be emitted with zero amount0 and amount1 when the caller chooses not to collect fees
              /// @param owner The owner of the position for which fees are collected
              /// @param tickLower The lower tick of the position
              /// @param tickUpper The upper tick of the position
              /// @param amount0 The amount of token0 fees collected
              /// @param amount1 The amount of token1 fees collected
              event Collect(
                  address indexed owner,
                  address recipient,
                  int24 indexed tickLower,
                  int24 indexed tickUpper,
                  uint128 amount0,
                  uint128 amount1
              );
              /// @notice Emitted when a position's liquidity is removed
              /// @dev Does not withdraw any fees earned by the liquidity position, which must be withdrawn via #collect
              /// @param owner The owner of the position for which liquidity is removed
              /// @param tickLower The lower tick of the position
              /// @param tickUpper The upper tick of the position
              /// @param amount The amount of liquidity to remove
              /// @param amount0 The amount of token0 withdrawn
              /// @param amount1 The amount of token1 withdrawn
              event Burn(
                  address indexed owner,
                  int24 indexed tickLower,
                  int24 indexed tickUpper,
                  uint128 amount,
                  uint256 amount0,
                  uint256 amount1
              );
              /// @notice Emitted by the pool for any swaps between token0 and token1
              /// @param sender The address that initiated the swap call, and that received the callback
              /// @param recipient The address that received the output of the swap
              /// @param amount0 The delta of the token0 balance of the pool
              /// @param amount1 The delta of the token1 balance of the pool
              /// @param sqrtPriceX96 The sqrt(price) of the pool after the swap, as a Q64.96
              /// @param liquidity The liquidity of the pool after the swap
              /// @param tick The log base 1.0001 of price of the pool after the swap
              event Swap(
                  address indexed sender,
                  address indexed recipient,
                  int256 amount0,
                  int256 amount1,
                  uint160 sqrtPriceX96,
                  uint128 liquidity,
                  int24 tick
              );
              /// @notice Emitted by the pool for any flashes of token0/token1
              /// @param sender The address that initiated the swap call, and that received the callback
              /// @param recipient The address that received the tokens from flash
              /// @param amount0 The amount of token0 that was flashed
              /// @param amount1 The amount of token1 that was flashed
              /// @param paid0 The amount of token0 paid for the flash, which can exceed the amount0 plus the fee
              /// @param paid1 The amount of token1 paid for the flash, which can exceed the amount1 plus the fee
              event Flash(
                  address indexed sender,
                  address indexed recipient,
                  uint256 amount0,
                  uint256 amount1,
                  uint256 paid0,
                  uint256 paid1
              );
              /// @notice Emitted by the pool for increases to the number of observations that can be stored
              /// @dev observationCardinalityNext is not the observation cardinality until an observation is written at the index
              /// just before a mint/swap/burn.
              /// @param observationCardinalityNextOld The previous value of the next observation cardinality
              /// @param observationCardinalityNextNew The updated value of the next observation cardinality
              event IncreaseObservationCardinalityNext(
                  uint16 observationCardinalityNextOld,
                  uint16 observationCardinalityNextNew
              );
              /// @notice Emitted when the protocol fee is changed by the pool
              /// @param feeProtocol0Old The previous value of the token0 protocol fee
              /// @param feeProtocol1Old The previous value of the token1 protocol fee
              /// @param feeProtocol0New The updated value of the token0 protocol fee
              /// @param feeProtocol1New The updated value of the token1 protocol fee
              event SetFeeProtocol(uint8 feeProtocol0Old, uint8 feeProtocol1Old, uint8 feeProtocol0New, uint8 feeProtocol1New);
              /// @notice Emitted when the collected protocol fees are withdrawn by the factory owner
              /// @param sender The address that collects the protocol fees
              /// @param recipient The address that receives the collected protocol fees
              /// @param amount0 The amount of token0 protocol fees that is withdrawn
              /// @param amount0 The amount of token1 protocol fees that is withdrawn
              event CollectProtocol(address indexed sender, address indexed recipient, uint128 amount0, uint128 amount1);
          }
          // SPDX-License-Identifier: GPL-2.0-or-later
          pragma solidity >=0.5.0;
          /// @title BitMath
          /// @dev This library provides functionality for computing bit properties of an unsigned integer
          library BitMath {
              /// @notice Returns the index of the most significant bit of the number,
              ///     where the least significant bit is at index 0 and the most significant bit is at index 255
              /// @dev The function satisfies the property:
              ///     x >= 2**mostSignificantBit(x) and x < 2**(mostSignificantBit(x)+1)
              /// @param x the value for which to compute the most significant bit, must be greater than 0
              /// @return r the index of the most significant bit
              function mostSignificantBit(uint256 x) internal pure returns (uint8 r) {
                  require(x > 0);
                  if (x >= 0x100000000000000000000000000000000) {
                      x >>= 128;
                      r += 128;
                  }
                  if (x >= 0x10000000000000000) {
                      x >>= 64;
                      r += 64;
                  }
                  if (x >= 0x100000000) {
                      x >>= 32;
                      r += 32;
                  }
                  if (x >= 0x10000) {
                      x >>= 16;
                      r += 16;
                  }
                  if (x >= 0x100) {
                      x >>= 8;
                      r += 8;
                  }
                  if (x >= 0x10) {
                      x >>= 4;
                      r += 4;
                  }
                  if (x >= 0x4) {
                      x >>= 2;
                      r += 2;
                  }
                  if (x >= 0x2) r += 1;
              }
              /// @notice Returns the index of the least significant bit of the number,
              ///     where the least significant bit is at index 0 and the most significant bit is at index 255
              /// @dev The function satisfies the property:
              ///     (x & 2**leastSignificantBit(x)) != 0 and (x & (2**(leastSignificantBit(x)) - 1)) == 0)
              /// @param x the value for which to compute the least significant bit, must be greater than 0
              /// @return r the index of the least significant bit
              function leastSignificantBit(uint256 x) internal pure returns (uint8 r) {
                  require(x > 0);
                  r = 255;
                  if (x & type(uint128).max > 0) {
                      r -= 128;
                  } else {
                      x >>= 128;
                  }
                  if (x & type(uint64).max > 0) {
                      r -= 64;
                  } else {
                      x >>= 64;
                  }
                  if (x & type(uint32).max > 0) {
                      r -= 32;
                  } else {
                      x >>= 32;
                  }
                  if (x & type(uint16).max > 0) {
                      r -= 16;
                  } else {
                      x >>= 16;
                  }
                  if (x & type(uint8).max > 0) {
                      r -= 8;
                  } else {
                      x >>= 8;
                  }
                  if (x & 0xf > 0) {
                      r -= 4;
                  } else {
                      x >>= 4;
                  }
                  if (x & 0x3 > 0) {
                      r -= 2;
                  } else {
                      x >>= 2;
                  }
                  if (x & 0x1 > 0) r -= 1;
              }
          }
          // SPDX-License-Identifier: GPL-2.0-or-later
          pragma solidity >=0.5.0;
          /// @title Math functions that do not check inputs or outputs
          /// @notice Contains methods that perform common math functions but do not do any overflow or underflow checks
          library UnsafeMath {
              /// @notice Returns ceil(x / y)
              /// @dev division by 0 has unspecified behavior, and must be checked externally
              /// @param x The dividend
              /// @param y The divisor
              /// @return z The quotient, ceil(x / y)
              function divRoundingUp(uint256 x, uint256 y) internal pure returns (uint256 z) {
                  assembly {
                      z := add(div(x, y), gt(mod(x, y), 0))
                  }
              }
          }
          // SPDX-License-Identifier: GPL-2.0-or-later
          pragma solidity >=0.4.0;
          /// @title FixedPoint96
          /// @notice A library for handling binary fixed point numbers, see https://en.wikipedia.org/wiki/Q_(number_format)
          /// @dev Used in SqrtPriceMath.sol
          library FixedPoint96 {
              uint8 internal constant RESOLUTION = 96;
              uint256 internal constant Q96 = 0x1000000000000000000000000;
          }
          

          File 3 of 4: PromptToken
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.0;
          import { IMessageLibManager } from "./IMessageLibManager.sol";
          import { IMessagingComposer } from "./IMessagingComposer.sol";
          import { IMessagingChannel } from "./IMessagingChannel.sol";
          import { IMessagingContext } from "./IMessagingContext.sol";
          struct MessagingParams {
              uint32 dstEid;
              bytes32 receiver;
              bytes message;
              bytes options;
              bool payInLzToken;
          }
          struct MessagingReceipt {
              bytes32 guid;
              uint64 nonce;
              MessagingFee fee;
          }
          struct MessagingFee {
              uint256 nativeFee;
              uint256 lzTokenFee;
          }
          struct Origin {
              uint32 srcEid;
              bytes32 sender;
              uint64 nonce;
          }
          interface ILayerZeroEndpointV2 is IMessageLibManager, IMessagingComposer, IMessagingChannel, IMessagingContext {
              event PacketSent(bytes encodedPayload, bytes options, address sendLibrary);
              event PacketVerified(Origin origin, address receiver, bytes32 payloadHash);
              event PacketDelivered(Origin origin, address receiver);
              event LzReceiveAlert(
                  address indexed receiver,
                  address indexed executor,
                  Origin origin,
                  bytes32 guid,
                  uint256 gas,
                  uint256 value,
                  bytes message,
                  bytes extraData,
                  bytes reason
              );
              event LzTokenSet(address token);
              event DelegateSet(address sender, address delegate);
              function quote(MessagingParams calldata _params, address _sender) external view returns (MessagingFee memory);
              function send(
                  MessagingParams calldata _params,
                  address _refundAddress
              ) external payable returns (MessagingReceipt memory);
              function verify(Origin calldata _origin, address _receiver, bytes32 _payloadHash) external;
              function verifiable(Origin calldata _origin, address _receiver) external view returns (bool);
              function initializable(Origin calldata _origin, address _receiver) external view returns (bool);
              function lzReceive(
                  Origin calldata _origin,
                  address _receiver,
                  bytes32 _guid,
                  bytes calldata _message,
                  bytes calldata _extraData
              ) external payable;
              // oapp can burn messages partially by calling this function with its own business logic if messages are verified in order
              function clear(address _oapp, Origin calldata _origin, bytes32 _guid, bytes calldata _message) external;
              function setLzToken(address _lzToken) external;
              function lzToken() external view returns (address);
              function nativeToken() external view returns (address);
              function setDelegate(address _delegate) external;
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.0;
          import { Origin } from "./ILayerZeroEndpointV2.sol";
          interface ILayerZeroReceiver {
              function allowInitializePath(Origin calldata _origin) external view returns (bool);
              function nextNonce(uint32 _eid, bytes32 _sender) external view returns (uint64);
              function lzReceive(
                  Origin calldata _origin,
                  bytes32 _guid,
                  bytes calldata _message,
                  address _executor,
                  bytes calldata _extraData
              ) external payable;
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.0;
          import { IERC165 } from "@openzeppelin/contracts/utils/introspection/IERC165.sol";
          import { SetConfigParam } from "./IMessageLibManager.sol";
          enum MessageLibType {
              Send,
              Receive,
              SendAndReceive
          }
          interface IMessageLib is IERC165 {
              function setConfig(address _oapp, SetConfigParam[] calldata _config) external;
              function getConfig(uint32 _eid, address _oapp, uint32 _configType) external view returns (bytes memory config);
              function isSupportedEid(uint32 _eid) external view returns (bool);
              // message libs of same major version are compatible
              function version() external view returns (uint64 major, uint8 minor, uint8 endpointVersion);
              function messageLibType() external view returns (MessageLibType);
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.0;
          struct SetConfigParam {
              uint32 eid;
              uint32 configType;
              bytes config;
          }
          interface IMessageLibManager {
              struct Timeout {
                  address lib;
                  uint256 expiry;
              }
              event LibraryRegistered(address newLib);
              event DefaultSendLibrarySet(uint32 eid, address newLib);
              event DefaultReceiveLibrarySet(uint32 eid, address newLib);
              event DefaultReceiveLibraryTimeoutSet(uint32 eid, address oldLib, uint256 expiry);
              event SendLibrarySet(address sender, uint32 eid, address newLib);
              event ReceiveLibrarySet(address receiver, uint32 eid, address newLib);
              event ReceiveLibraryTimeoutSet(address receiver, uint32 eid, address oldLib, uint256 timeout);
              function registerLibrary(address _lib) external;
              function isRegisteredLibrary(address _lib) external view returns (bool);
              function getRegisteredLibraries() external view returns (address[] memory);
              function setDefaultSendLibrary(uint32 _eid, address _newLib) external;
              function defaultSendLibrary(uint32 _eid) external view returns (address);
              function setDefaultReceiveLibrary(uint32 _eid, address _newLib, uint256 _gracePeriod) external;
              function defaultReceiveLibrary(uint32 _eid) external view returns (address);
              function setDefaultReceiveLibraryTimeout(uint32 _eid, address _lib, uint256 _expiry) external;
              function defaultReceiveLibraryTimeout(uint32 _eid) external view returns (address lib, uint256 expiry);
              function isSupportedEid(uint32 _eid) external view returns (bool);
              function isValidReceiveLibrary(address _receiver, uint32 _eid, address _lib) external view returns (bool);
              /// ------------------- OApp interfaces -------------------
              function setSendLibrary(address _oapp, uint32 _eid, address _newLib) external;
              function getSendLibrary(address _sender, uint32 _eid) external view returns (address lib);
              function isDefaultSendLibrary(address _sender, uint32 _eid) external view returns (bool);
              function setReceiveLibrary(address _oapp, uint32 _eid, address _newLib, uint256 _gracePeriod) external;
              function getReceiveLibrary(address _receiver, uint32 _eid) external view returns (address lib, bool isDefault);
              function setReceiveLibraryTimeout(address _oapp, uint32 _eid, address _lib, uint256 _expiry) external;
              function receiveLibraryTimeout(address _receiver, uint32 _eid) external view returns (address lib, uint256 expiry);
              function setConfig(address _oapp, address _lib, SetConfigParam[] calldata _params) external;
              function getConfig(
                  address _oapp,
                  address _lib,
                  uint32 _eid,
                  uint32 _configType
              ) external view returns (bytes memory config);
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.0;
          interface IMessagingChannel {
              event InboundNonceSkipped(uint32 srcEid, bytes32 sender, address receiver, uint64 nonce);
              event PacketNilified(uint32 srcEid, bytes32 sender, address receiver, uint64 nonce, bytes32 payloadHash);
              event PacketBurnt(uint32 srcEid, bytes32 sender, address receiver, uint64 nonce, bytes32 payloadHash);
              function eid() external view returns (uint32);
              // this is an emergency function if a message cannot be verified for some reasons
              // required to provide _nextNonce to avoid race condition
              function skip(address _oapp, uint32 _srcEid, bytes32 _sender, uint64 _nonce) external;
              function nilify(address _oapp, uint32 _srcEid, bytes32 _sender, uint64 _nonce, bytes32 _payloadHash) external;
              function burn(address _oapp, uint32 _srcEid, bytes32 _sender, uint64 _nonce, bytes32 _payloadHash) external;
              function nextGuid(address _sender, uint32 _dstEid, bytes32 _receiver) external view returns (bytes32);
              function inboundNonce(address _receiver, uint32 _srcEid, bytes32 _sender) external view returns (uint64);
              function outboundNonce(address _sender, uint32 _dstEid, bytes32 _receiver) external view returns (uint64);
              function inboundPayloadHash(
                  address _receiver,
                  uint32 _srcEid,
                  bytes32 _sender,
                  uint64 _nonce
              ) external view returns (bytes32);
              function lazyInboundNonce(address _receiver, uint32 _srcEid, bytes32 _sender) external view returns (uint64);
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.0;
          interface IMessagingComposer {
              event ComposeSent(address from, address to, bytes32 guid, uint16 index, bytes message);
              event ComposeDelivered(address from, address to, bytes32 guid, uint16 index);
              event LzComposeAlert(
                  address indexed from,
                  address indexed to,
                  address indexed executor,
                  bytes32 guid,
                  uint16 index,
                  uint256 gas,
                  uint256 value,
                  bytes message,
                  bytes extraData,
                  bytes reason
              );
              function composeQueue(
                  address _from,
                  address _to,
                  bytes32 _guid,
                  uint16 _index
              ) external view returns (bytes32 messageHash);
              function sendCompose(address _to, bytes32 _guid, uint16 _index, bytes calldata _message) external;
              function lzCompose(
                  address _from,
                  address _to,
                  bytes32 _guid,
                  uint16 _index,
                  bytes calldata _message,
                  bytes calldata _extraData
              ) external payable;
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.0;
          interface IMessagingContext {
              function isSendingMessage() external view returns (bool);
              function getSendContext() external view returns (uint32 dstEid, address sender);
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.8.0;
          import { MessagingFee } from "./ILayerZeroEndpointV2.sol";
          import { IMessageLib } from "./IMessageLib.sol";
          struct Packet {
              uint64 nonce;
              uint32 srcEid;
              address sender;
              uint32 dstEid;
              bytes32 receiver;
              bytes32 guid;
              bytes message;
          }
          interface ISendLib is IMessageLib {
              function send(
                  Packet calldata _packet,
                  bytes calldata _options,
                  bool _payInLzToken
              ) external returns (MessagingFee memory, bytes memory encodedPacket);
              function quote(
                  Packet calldata _packet,
                  bytes calldata _options,
                  bool _payInLzToken
              ) external view returns (MessagingFee memory);
              function setTreasury(address _treasury) external;
              function withdrawFee(address _to, uint256 _amount) external;
              function withdrawLzTokenFee(address _lzToken, address _to, uint256 _amount) external;
          }
          // SPDX-License-Identifier: LZBL-1.2
          pragma solidity ^0.8.20;
          library AddressCast {
              error AddressCast_InvalidSizeForAddress();
              error AddressCast_InvalidAddress();
              function toBytes32(bytes calldata _addressBytes) internal pure returns (bytes32 result) {
                  if (_addressBytes.length > 32) revert AddressCast_InvalidAddress();
                  result = bytes32(_addressBytes);
                  unchecked {
                      uint256 offset = 32 - _addressBytes.length;
                      result = result >> (offset * 8);
                  }
              }
              function toBytes32(address _address) internal pure returns (bytes32 result) {
                  result = bytes32(uint256(uint160(_address)));
              }
              function toBytes(bytes32 _addressBytes32, uint256 _size) internal pure returns (bytes memory result) {
                  if (_size == 0 || _size > 32) revert AddressCast_InvalidSizeForAddress();
                  result = new bytes(_size);
                  unchecked {
                      uint256 offset = 256 - _size * 8;
                      assembly {
                          mstore(add(result, 32), shl(offset, _addressBytes32))
                      }
                  }
              }
              function toAddress(bytes32 _addressBytes32) internal pure returns (address result) {
                  result = address(uint160(uint256(_addressBytes32)));
              }
              function toAddress(bytes calldata _addressBytes) internal pure returns (address result) {
                  if (_addressBytes.length != 20) revert AddressCast_InvalidAddress();
                  result = address(bytes20(_addressBytes));
              }
          }
          // SPDX-License-Identifier: LZBL-1.2
          pragma solidity ^0.8.20;
          import { Packet } from "../../interfaces/ISendLib.sol";
          import { AddressCast } from "../../libs/AddressCast.sol";
          library PacketV1Codec {
              using AddressCast for address;
              using AddressCast for bytes32;
              uint8 internal constant PACKET_VERSION = 1;
              // header (version + nonce + path)
              // version
              uint256 private constant PACKET_VERSION_OFFSET = 0;
              //    nonce
              uint256 private constant NONCE_OFFSET = 1;
              //    path
              uint256 private constant SRC_EID_OFFSET = 9;
              uint256 private constant SENDER_OFFSET = 13;
              uint256 private constant DST_EID_OFFSET = 45;
              uint256 private constant RECEIVER_OFFSET = 49;
              // payload (guid + message)
              uint256 private constant GUID_OFFSET = 81; // keccak256(nonce + path)
              uint256 private constant MESSAGE_OFFSET = 113;
              function encode(Packet memory _packet) internal pure returns (bytes memory encodedPacket) {
                  encodedPacket = abi.encodePacked(
                      PACKET_VERSION,
                      _packet.nonce,
                      _packet.srcEid,
                      _packet.sender.toBytes32(),
                      _packet.dstEid,
                      _packet.receiver,
                      _packet.guid,
                      _packet.message
                  );
              }
              function encodePacketHeader(Packet memory _packet) internal pure returns (bytes memory) {
                  return
                      abi.encodePacked(
                          PACKET_VERSION,
                          _packet.nonce,
                          _packet.srcEid,
                          _packet.sender.toBytes32(),
                          _packet.dstEid,
                          _packet.receiver
                      );
              }
              function encodePayload(Packet memory _packet) internal pure returns (bytes memory) {
                  return abi.encodePacked(_packet.guid, _packet.message);
              }
              function header(bytes calldata _packet) internal pure returns (bytes calldata) {
                  return _packet[0:GUID_OFFSET];
              }
              function version(bytes calldata _packet) internal pure returns (uint8) {
                  return uint8(bytes1(_packet[PACKET_VERSION_OFFSET:NONCE_OFFSET]));
              }
              function nonce(bytes calldata _packet) internal pure returns (uint64) {
                  return uint64(bytes8(_packet[NONCE_OFFSET:SRC_EID_OFFSET]));
              }
              function srcEid(bytes calldata _packet) internal pure returns (uint32) {
                  return uint32(bytes4(_packet[SRC_EID_OFFSET:SENDER_OFFSET]));
              }
              function sender(bytes calldata _packet) internal pure returns (bytes32) {
                  return bytes32(_packet[SENDER_OFFSET:DST_EID_OFFSET]);
              }
              function senderAddressB20(bytes calldata _packet) internal pure returns (address) {
                  return sender(_packet).toAddress();
              }
              function dstEid(bytes calldata _packet) internal pure returns (uint32) {
                  return uint32(bytes4(_packet[DST_EID_OFFSET:RECEIVER_OFFSET]));
              }
              function receiver(bytes calldata _packet) internal pure returns (bytes32) {
                  return bytes32(_packet[RECEIVER_OFFSET:GUID_OFFSET]);
              }
              function receiverB20(bytes calldata _packet) internal pure returns (address) {
                  return receiver(_packet).toAddress();
              }
              function guid(bytes calldata _packet) internal pure returns (bytes32) {
                  return bytes32(_packet[GUID_OFFSET:MESSAGE_OFFSET]);
              }
              function message(bytes calldata _packet) internal pure returns (bytes calldata) {
                  return bytes(_packet[MESSAGE_OFFSET:]);
              }
              function payload(bytes calldata _packet) internal pure returns (bytes calldata) {
                  return bytes(_packet[GUID_OFFSET:]);
              }
              function payloadHash(bytes calldata _packet) internal pure returns (bytes32) {
                  return keccak256(payload(_packet));
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.20;
          import { ILayerZeroEndpointV2 } from "@layerzerolabs/lz-evm-protocol-v2/contracts/interfaces/ILayerZeroEndpointV2.sol";
          /**
           * @title IOAppCore
           */
          interface IOAppCore {
              // Custom error messages
              error OnlyPeer(uint32 eid, bytes32 sender);
              error NoPeer(uint32 eid);
              error InvalidEndpointCall();
              error InvalidDelegate();
              // Event emitted when a peer (OApp) is set for a corresponding endpoint
              event PeerSet(uint32 eid, bytes32 peer);
              /**
               * @notice Retrieves the OApp version information.
               * @return senderVersion The version of the OAppSender.sol contract.
               * @return receiverVersion The version of the OAppReceiver.sol contract.
               */
              function oAppVersion() external view returns (uint64 senderVersion, uint64 receiverVersion);
              /**
               * @notice Retrieves the LayerZero endpoint associated with the OApp.
               * @return iEndpoint The LayerZero endpoint as an interface.
               */
              function endpoint() external view returns (ILayerZeroEndpointV2 iEndpoint);
              /**
               * @notice Retrieves the peer (OApp) associated with a corresponding endpoint.
               * @param _eid The endpoint ID.
               * @return peer The peer address (OApp instance) associated with the corresponding endpoint.
               */
              function peers(uint32 _eid) external view returns (bytes32 peer);
              /**
               * @notice Sets the peer address (OApp instance) for a corresponding endpoint.
               * @param _eid The endpoint ID.
               * @param _peer The address of the peer to be associated with the corresponding endpoint.
               */
              function setPeer(uint32 _eid, bytes32 _peer) external;
              /**
               * @notice Sets the delegate address for the OApp Core.
               * @param _delegate The address of the delegate to be set.
               */
              function setDelegate(address _delegate) external;
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.20;
          /**
           * @title IOAppMsgInspector
           * @dev Interface for the OApp Message Inspector, allowing examination of message and options contents.
           */
          interface IOAppMsgInspector {
              // Custom error message for inspection failure
              error InspectionFailed(bytes message, bytes options);
              /**
               * @notice Allows the inspector to examine LayerZero message contents and optionally throw a revert if invalid.
               * @param _message The message payload to be inspected.
               * @param _options Additional options or parameters for inspection.
               * @return valid A boolean indicating whether the inspection passed (true) or failed (false).
               *
               * @dev Optionally done as a revert, OR use the boolean provided to handle the failure.
               */
              function inspect(bytes calldata _message, bytes calldata _options) external view returns (bool valid);
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.20;
          /**
           * @dev Struct representing enforced option parameters.
           */
          struct EnforcedOptionParam {
              uint32 eid; // Endpoint ID
              uint16 msgType; // Message Type
              bytes options; // Additional options
          }
          /**
           * @title IOAppOptionsType3
           * @dev Interface for the OApp with Type 3 Options, allowing the setting and combining of enforced options.
           */
          interface IOAppOptionsType3 {
              // Custom error message for invalid options
              error InvalidOptions(bytes options);
              // Event emitted when enforced options are set
              event EnforcedOptionSet(EnforcedOptionParam[] _enforcedOptions);
              /**
               * @notice Sets enforced options for specific endpoint and message type combinations.
               * @param _enforcedOptions An array of EnforcedOptionParam structures specifying enforced options.
               */
              function setEnforcedOptions(EnforcedOptionParam[] calldata _enforcedOptions) external;
              /**
               * @notice Combines options for a given endpoint and message type.
               * @param _eid The endpoint ID.
               * @param _msgType The OApp message type.
               * @param _extraOptions Additional options passed by the caller.
               * @return options The combination of caller specified options AND enforced options.
               */
              function combineOptions(
                  uint32 _eid,
                  uint16 _msgType,
                  bytes calldata _extraOptions
              ) external view returns (bytes memory options);
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.20;
          import { ILayerZeroReceiver, Origin } from "@layerzerolabs/lz-evm-protocol-v2/contracts/interfaces/ILayerZeroReceiver.sol";
          interface IOAppReceiver is ILayerZeroReceiver {
              /**
               * @notice Indicates whether an address is an approved composeMsg sender to the Endpoint.
               * @param _origin The origin information containing the source endpoint and sender address.
               *  - srcEid: The source chain endpoint ID.
               *  - sender: The sender address on the src chain.
               *  - nonce: The nonce of the message.
               * @param _message The lzReceive payload.
               * @param _sender The sender address.
               * @return isSender Is a valid sender.
               *
               * @dev Applications can optionally choose to implement a separate composeMsg sender that is NOT the bridging layer.
               * @dev The default sender IS the OAppReceiver implementer.
               */
              function isComposeMsgSender(
                  Origin calldata _origin,
                  bytes calldata _message,
                  address _sender
              ) external view returns (bool isSender);
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.20;
          import { Ownable } from "@openzeppelin/contracts/access/Ownable.sol";
          import { IOAppOptionsType3, EnforcedOptionParam } from "../interfaces/IOAppOptionsType3.sol";
          /**
           * @title OAppOptionsType3
           * @dev Abstract contract implementing the IOAppOptionsType3 interface with type 3 options.
           */
          abstract contract OAppOptionsType3 is IOAppOptionsType3, Ownable {
              uint16 internal constant OPTION_TYPE_3 = 3;
              // @dev The "msgType" should be defined in the child contract.
              mapping(uint32 eid => mapping(uint16 msgType => bytes enforcedOption)) public enforcedOptions;
              /**
               * @dev Sets the enforced options for specific endpoint and message type combinations.
               * @param _enforcedOptions An array of EnforcedOptionParam structures specifying enforced options.
               *
               * @dev Only the owner/admin of the OApp can call this function.
               * @dev Provides a way for the OApp to enforce things like paying for PreCrime, AND/OR minimum dst lzReceive gas amounts etc.
               * @dev These enforced options can vary as the potential options/execution on the remote may differ as per the msgType.
               * eg. Amount of lzReceive() gas necessary to deliver a lzCompose() message adds overhead you dont want to pay
               * if you are only making a standard LayerZero message ie. lzReceive() WITHOUT sendCompose().
               */
              function setEnforcedOptions(EnforcedOptionParam[] calldata _enforcedOptions) public virtual onlyOwner {
                  _setEnforcedOptions(_enforcedOptions);
              }
              /**
               * @dev Sets the enforced options for specific endpoint and message type combinations.
               * @param _enforcedOptions An array of EnforcedOptionParam structures specifying enforced options.
               *
               * @dev Provides a way for the OApp to enforce things like paying for PreCrime, AND/OR minimum dst lzReceive gas amounts etc.
               * @dev These enforced options can vary as the potential options/execution on the remote may differ as per the msgType.
               * eg. Amount of lzReceive() gas necessary to deliver a lzCompose() message adds overhead you dont want to pay
               * if you are only making a standard LayerZero message ie. lzReceive() WITHOUT sendCompose().
               */
              function _setEnforcedOptions(EnforcedOptionParam[] memory _enforcedOptions) internal virtual {
                  for (uint256 i = 0; i < _enforcedOptions.length; i++) {
                      // @dev Enforced options are only available for optionType 3, as type 1 and 2 dont support combining.
                      _assertOptionsType3(_enforcedOptions[i].options);
                      enforcedOptions[_enforcedOptions[i].eid][_enforcedOptions[i].msgType] = _enforcedOptions[i].options;
                  }
                  emit EnforcedOptionSet(_enforcedOptions);
              }
              /**
               * @notice Combines options for a given endpoint and message type.
               * @param _eid The endpoint ID.
               * @param _msgType The OAPP message type.
               * @param _extraOptions Additional options passed by the caller.
               * @return options The combination of caller specified options AND enforced options.
               *
               * @dev If there is an enforced lzReceive option:
               * - {gasLimit: 200k, msg.value: 1 ether} AND a caller supplies a lzReceive option: {gasLimit: 100k, msg.value: 0.5 ether}
               * - The resulting options will be {gasLimit: 300k, msg.value: 1.5 ether} when the message is executed on the remote lzReceive() function.
               * @dev This presence of duplicated options is handled off-chain in the verifier/executor.
               */
              function combineOptions(
                  uint32 _eid,
                  uint16 _msgType,
                  bytes calldata _extraOptions
              ) public view virtual returns (bytes memory) {
                  bytes memory enforced = enforcedOptions[_eid][_msgType];
                  // No enforced options, pass whatever the caller supplied, even if it's empty or legacy type 1/2 options.
                  if (enforced.length == 0) return _extraOptions;
                  // No caller options, return enforced
                  if (_extraOptions.length == 0) return enforced;
                  // @dev If caller provided _extraOptions, must be type 3 as its the ONLY type that can be combined.
                  if (_extraOptions.length >= 2) {
                      _assertOptionsType3(_extraOptions);
                      // @dev Remove the first 2 bytes containing the type from the _extraOptions and combine with enforced.
                      return bytes.concat(enforced, _extraOptions[2:]);
                  }
                  // No valid set of options was found.
                  revert InvalidOptions(_extraOptions);
              }
              /**
               * @dev Internal function to assert that options are of type 3.
               * @param _options The options to be checked.
               */
              function _assertOptionsType3(bytes memory _options) internal pure virtual {
                  uint16 optionsType;
                  assembly {
                      optionsType := mload(add(_options, 2))
                  }
                  if (optionsType != OPTION_TYPE_3) revert InvalidOptions(_options);
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.20;
          // @dev Import the 'MessagingFee' and 'MessagingReceipt' so it's exposed to OApp implementers
          // solhint-disable-next-line no-unused-import
          import { OAppSender, MessagingFee, MessagingReceipt } from "./OAppSender.sol";
          // @dev Import the 'Origin' so it's exposed to OApp implementers
          // solhint-disable-next-line no-unused-import
          import { OAppReceiver, Origin } from "./OAppReceiver.sol";
          import { OAppCore } from "./OAppCore.sol";
          /**
           * @title OApp
           * @dev Abstract contract serving as the base for OApp implementation, combining OAppSender and OAppReceiver functionality.
           */
          abstract contract OApp is OAppSender, OAppReceiver {
              /**
               * @dev Constructor to initialize the OApp with the provided endpoint and owner.
               * @param _endpoint The address of the LOCAL LayerZero endpoint.
               * @param _delegate The delegate capable of making OApp configurations inside of the endpoint.
               */
              constructor(address _endpoint, address _delegate) OAppCore(_endpoint, _delegate) {}
              /**
               * @notice Retrieves the OApp version information.
               * @return senderVersion The version of the OAppSender.sol implementation.
               * @return receiverVersion The version of the OAppReceiver.sol implementation.
               */
              function oAppVersion()
                  public
                  pure
                  virtual
                  override(OAppSender, OAppReceiver)
                  returns (uint64 senderVersion, uint64 receiverVersion)
              {
                  return (SENDER_VERSION, RECEIVER_VERSION);
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.20;
          import { Ownable } from "@openzeppelin/contracts/access/Ownable.sol";
          import { IOAppCore, ILayerZeroEndpointV2 } from "./interfaces/IOAppCore.sol";
          /**
           * @title OAppCore
           * @dev Abstract contract implementing the IOAppCore interface with basic OApp configurations.
           */
          abstract contract OAppCore is IOAppCore, Ownable {
              // The LayerZero endpoint associated with the given OApp
              ILayerZeroEndpointV2 public immutable endpoint;
              // Mapping to store peers associated with corresponding endpoints
              mapping(uint32 eid => bytes32 peer) public peers;
              /**
               * @dev Constructor to initialize the OAppCore with the provided endpoint and delegate.
               * @param _endpoint The address of the LOCAL Layer Zero endpoint.
               * @param _delegate The delegate capable of making OApp configurations inside of the endpoint.
               *
               * @dev The delegate typically should be set as the owner of the contract.
               */
              constructor(address _endpoint, address _delegate) {
                  endpoint = ILayerZeroEndpointV2(_endpoint);
                  if (_delegate == address(0)) revert InvalidDelegate();
                  endpoint.setDelegate(_delegate);
              }
              /**
               * @notice Sets the peer address (OApp instance) for a corresponding endpoint.
               * @param _eid The endpoint ID.
               * @param _peer The address of the peer to be associated with the corresponding endpoint.
               *
               * @dev Only the owner/admin of the OApp can call this function.
               * @dev Indicates that the peer is trusted to send LayerZero messages to this OApp.
               * @dev Set this to bytes32(0) to remove the peer address.
               * @dev Peer is a bytes32 to accommodate non-evm chains.
               */
              function setPeer(uint32 _eid, bytes32 _peer) public virtual onlyOwner {
                  _setPeer(_eid, _peer);
              }
              /**
               * @notice Sets the peer address (OApp instance) for a corresponding endpoint.
               * @param _eid The endpoint ID.
               * @param _peer The address of the peer to be associated with the corresponding endpoint.
               *
               * @dev Indicates that the peer is trusted to send LayerZero messages to this OApp.
               * @dev Set this to bytes32(0) to remove the peer address.
               * @dev Peer is a bytes32 to accommodate non-evm chains.
               */
              function _setPeer(uint32 _eid, bytes32 _peer) internal virtual {
                  peers[_eid] = _peer;
                  emit PeerSet(_eid, _peer);
              }
              /**
               * @notice Internal function to get the peer address associated with a specific endpoint; reverts if NOT set.
               * ie. the peer is set to bytes32(0).
               * @param _eid The endpoint ID.
               * @return peer The address of the peer associated with the specified endpoint.
               */
              function _getPeerOrRevert(uint32 _eid) internal view virtual returns (bytes32) {
                  bytes32 peer = peers[_eid];
                  if (peer == bytes32(0)) revert NoPeer(_eid);
                  return peer;
              }
              /**
               * @notice Sets the delegate address for the OApp.
               * @param _delegate The address of the delegate to be set.
               *
               * @dev Only the owner/admin of the OApp can call this function.
               * @dev Provides the ability for a delegate to set configs, on behalf of the OApp, directly on the Endpoint contract.
               */
              function setDelegate(address _delegate) public onlyOwner {
                  endpoint.setDelegate(_delegate);
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.20;
          import { IOAppReceiver, Origin } from "./interfaces/IOAppReceiver.sol";
          import { OAppCore } from "./OAppCore.sol";
          /**
           * @title OAppReceiver
           * @dev Abstract contract implementing the ILayerZeroReceiver interface and extending OAppCore for OApp receivers.
           */
          abstract contract OAppReceiver is IOAppReceiver, OAppCore {
              // Custom error message for when the caller is not the registered endpoint/
              error OnlyEndpoint(address addr);
              // @dev The version of the OAppReceiver implementation.
              // @dev Version is bumped when changes are made to this contract.
              uint64 internal constant RECEIVER_VERSION = 2;
              /**
               * @notice Retrieves the OApp version information.
               * @return senderVersion The version of the OAppSender.sol contract.
               * @return receiverVersion The version of the OAppReceiver.sol contract.
               *
               * @dev Providing 0 as the default for OAppSender version. Indicates that the OAppSender is not implemented.
               * ie. this is a RECEIVE only OApp.
               * @dev If the OApp uses both OAppSender and OAppReceiver, then this needs to be override returning the correct versions.
               */
              function oAppVersion() public view virtual returns (uint64 senderVersion, uint64 receiverVersion) {
                  return (0, RECEIVER_VERSION);
              }
              /**
               * @notice Indicates whether an address is an approved composeMsg sender to the Endpoint.
               * @dev _origin The origin information containing the source endpoint and sender address.
               *  - srcEid: The source chain endpoint ID.
               *  - sender: The sender address on the src chain.
               *  - nonce: The nonce of the message.
               * @dev _message The lzReceive payload.
               * @param _sender The sender address.
               * @return isSender Is a valid sender.
               *
               * @dev Applications can optionally choose to implement separate composeMsg senders that are NOT the bridging layer.
               * @dev The default sender IS the OAppReceiver implementer.
               */
              function isComposeMsgSender(
                  Origin calldata /*_origin*/,
                  bytes calldata /*_message*/,
                  address _sender
              ) public view virtual returns (bool) {
                  return _sender == address(this);
              }
              /**
               * @notice Checks if the path initialization is allowed based on the provided origin.
               * @param origin The origin information containing the source endpoint and sender address.
               * @return Whether the path has been initialized.
               *
               * @dev This indicates to the endpoint that the OApp has enabled msgs for this particular path to be received.
               * @dev This defaults to assuming if a peer has been set, its initialized.
               * Can be overridden by the OApp if there is other logic to determine this.
               */
              function allowInitializePath(Origin calldata origin) public view virtual returns (bool) {
                  return peers[origin.srcEid] == origin.sender;
              }
              /**
               * @notice Retrieves the next nonce for a given source endpoint and sender address.
               * @dev _srcEid The source endpoint ID.
               * @dev _sender The sender address.
               * @return nonce The next nonce.
               *
               * @dev The path nonce starts from 1. If 0 is returned it means that there is NO nonce ordered enforcement.
               * @dev Is required by the off-chain executor to determine the OApp expects msg execution is ordered.
               * @dev This is also enforced by the OApp.
               * @dev By default this is NOT enabled. ie. nextNonce is hardcoded to return 0.
               */
              function nextNonce(uint32 /*_srcEid*/, bytes32 /*_sender*/) public view virtual returns (uint64 nonce) {
                  return 0;
              }
              /**
               * @dev Entry point for receiving messages or packets from the endpoint.
               * @param _origin The origin information containing the source endpoint and sender address.
               *  - srcEid: The source chain endpoint ID.
               *  - sender: The sender address on the src chain.
               *  - nonce: The nonce of the message.
               * @param _guid The unique identifier for the received LayerZero message.
               * @param _message The payload of the received message.
               * @param _executor The address of the executor for the received message.
               * @param _extraData Additional arbitrary data provided by the corresponding executor.
               *
               * @dev Entry point for receiving msg/packet from the LayerZero endpoint.
               */
              function lzReceive(
                  Origin calldata _origin,
                  bytes32 _guid,
                  bytes calldata _message,
                  address _executor,
                  bytes calldata _extraData
              ) public payable virtual {
                  // Ensures that only the endpoint can attempt to lzReceive() messages to this OApp.
                  if (address(endpoint) != msg.sender) revert OnlyEndpoint(msg.sender);
                  // Ensure that the sender matches the expected peer for the source endpoint.
                  if (_getPeerOrRevert(_origin.srcEid) != _origin.sender) revert OnlyPeer(_origin.srcEid, _origin.sender);
                  // Call the internal OApp implementation of lzReceive.
                  _lzReceive(_origin, _guid, _message, _executor, _extraData);
              }
              /**
               * @dev Internal function to implement lzReceive logic without needing to copy the basic parameter validation.
               */
              function _lzReceive(
                  Origin calldata _origin,
                  bytes32 _guid,
                  bytes calldata _message,
                  address _executor,
                  bytes calldata _extraData
              ) internal virtual;
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.20;
          import { SafeERC20, IERC20 } from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
          import { MessagingParams, MessagingFee, MessagingReceipt } from "@layerzerolabs/lz-evm-protocol-v2/contracts/interfaces/ILayerZeroEndpointV2.sol";
          import { OAppCore } from "./OAppCore.sol";
          /**
           * @title OAppSender
           * @dev Abstract contract implementing the OAppSender functionality for sending messages to a LayerZero endpoint.
           */
          abstract contract OAppSender is OAppCore {
              using SafeERC20 for IERC20;
              // Custom error messages
              error NotEnoughNative(uint256 msgValue);
              error LzTokenUnavailable();
              // @dev The version of the OAppSender implementation.
              // @dev Version is bumped when changes are made to this contract.
              uint64 internal constant SENDER_VERSION = 1;
              /**
               * @notice Retrieves the OApp version information.
               * @return senderVersion The version of the OAppSender.sol contract.
               * @return receiverVersion The version of the OAppReceiver.sol contract.
               *
               * @dev Providing 0 as the default for OAppReceiver version. Indicates that the OAppReceiver is not implemented.
               * ie. this is a SEND only OApp.
               * @dev If the OApp uses both OAppSender and OAppReceiver, then this needs to be override returning the correct versions
               */
              function oAppVersion() public view virtual returns (uint64 senderVersion, uint64 receiverVersion) {
                  return (SENDER_VERSION, 0);
              }
              /**
               * @dev Internal function to interact with the LayerZero EndpointV2.quote() for fee calculation.
               * @param _dstEid The destination endpoint ID.
               * @param _message The message payload.
               * @param _options Additional options for the message.
               * @param _payInLzToken Flag indicating whether to pay the fee in LZ tokens.
               * @return fee The calculated MessagingFee for the message.
               *      - nativeFee: The native fee for the message.
               *      - lzTokenFee: The LZ token fee for the message.
               */
              function _quote(
                  uint32 _dstEid,
                  bytes memory _message,
                  bytes memory _options,
                  bool _payInLzToken
              ) internal view virtual returns (MessagingFee memory fee) {
                  return
                      endpoint.quote(
                          MessagingParams(_dstEid, _getPeerOrRevert(_dstEid), _message, _options, _payInLzToken),
                          address(this)
                      );
              }
              /**
               * @dev Internal function to interact with the LayerZero EndpointV2.send() for sending a message.
               * @param _dstEid The destination endpoint ID.
               * @param _message The message payload.
               * @param _options Additional options for the message.
               * @param _fee The calculated LayerZero fee for the message.
               *      - nativeFee: The native fee.
               *      - lzTokenFee: The lzToken fee.
               * @param _refundAddress The address to receive any excess fee values sent to the endpoint.
               * @return receipt The receipt for the sent message.
               *      - guid: The unique identifier for the sent message.
               *      - nonce: The nonce of the sent message.
               *      - fee: The LayerZero fee incurred for the message.
               */
              function _lzSend(
                  uint32 _dstEid,
                  bytes memory _message,
                  bytes memory _options,
                  MessagingFee memory _fee,
                  address _refundAddress
              ) internal virtual returns (MessagingReceipt memory receipt) {
                  // @dev Push corresponding fees to the endpoint, any excess is sent back to the _refundAddress from the endpoint.
                  uint256 messageValue = _payNative(_fee.nativeFee);
                  if (_fee.lzTokenFee > 0) _payLzToken(_fee.lzTokenFee);
                  return
                      // solhint-disable-next-line check-send-result
                      endpoint.send{ value: messageValue }(
                          MessagingParams(_dstEid, _getPeerOrRevert(_dstEid), _message, _options, _fee.lzTokenFee > 0),
                          _refundAddress
                      );
              }
              /**
               * @dev Internal function to pay the native fee associated with the message.
               * @param _nativeFee The native fee to be paid.
               * @return nativeFee The amount of native currency paid.
               *
               * @dev If the OApp needs to initiate MULTIPLE LayerZero messages in a single transaction,
               * this will need to be overridden because msg.value would contain multiple lzFees.
               * @dev Should be overridden in the event the LayerZero endpoint requires a different native currency.
               * @dev Some EVMs use an ERC20 as a method for paying transactions/gasFees.
               * @dev The endpoint is EITHER/OR, ie. it will NOT support both types of native payment at a time.
               */
              function _payNative(uint256 _nativeFee) internal virtual returns (uint256 nativeFee) {
                  if (msg.value != _nativeFee) revert NotEnoughNative(msg.value);
                  return _nativeFee;
              }
              /**
               * @dev Internal function to pay the LZ token fee associated with the message.
               * @param _lzTokenFee The LZ token fee to be paid.
               *
               * @dev If the caller is trying to pay in the specified lzToken, then the lzTokenFee is passed to the endpoint.
               * @dev Any excess sent, is passed back to the specified _refundAddress in the _lzSend().
               */
              function _payLzToken(uint256 _lzTokenFee) internal virtual {
                  // @dev Cannot cache the token because it is not immutable in the endpoint.
                  address lzToken = endpoint.lzToken();
                  if (lzToken == address(0)) revert LzTokenUnavailable();
                  // Pay LZ token fee by sending tokens to the endpoint.
                  IERC20(lzToken).safeTransferFrom(msg.sender, address(endpoint), _lzTokenFee);
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.20;
          // @dev Import the Origin so it's exposed to OAppPreCrimeSimulator implementers.
          // solhint-disable-next-line no-unused-import
          import { InboundPacket, Origin } from "../libs/Packet.sol";
          /**
           * @title IOAppPreCrimeSimulator Interface
           * @dev Interface for the preCrime simulation functionality in an OApp.
           */
          interface IOAppPreCrimeSimulator {
              // @dev simulation result used in PreCrime implementation
              error SimulationResult(bytes result);
              error OnlySelf();
              /**
               * @dev Emitted when the preCrime contract address is set.
               * @param preCrimeAddress The address of the preCrime contract.
               */
              event PreCrimeSet(address preCrimeAddress);
              /**
               * @dev Retrieves the address of the preCrime contract implementation.
               * @return The address of the preCrime contract.
               */
              function preCrime() external view returns (address);
              /**
               * @dev Retrieves the address of the OApp contract.
               * @return The address of the OApp contract.
               */
              function oApp() external view returns (address);
              /**
               * @dev Sets the preCrime contract address.
               * @param _preCrime The address of the preCrime contract.
               */
              function setPreCrime(address _preCrime) external;
              /**
               * @dev Mocks receiving a packet, then reverts with a series of data to infer the state/result.
               * @param _packets An array of LayerZero InboundPacket objects representing received packets.
               */
              function lzReceiveAndRevert(InboundPacket[] calldata _packets) external payable;
              /**
               * @dev checks if the specified peer is considered 'trusted' by the OApp.
               * @param _eid The endpoint Id to check.
               * @param _peer The peer to check.
               * @return Whether the peer passed is considered 'trusted' by the OApp.
               */
              function isPeer(uint32 _eid, bytes32 _peer) external view returns (bool);
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.20;
          struct PreCrimePeer {
              uint32 eid;
              bytes32 preCrime;
              bytes32 oApp;
          }
          // TODO not done yet
          interface IPreCrime {
              error OnlyOffChain();
              // for simulate()
              error PacketOversize(uint256 max, uint256 actual);
              error PacketUnsorted();
              error SimulationFailed(bytes reason);
              // for preCrime()
              error SimulationResultNotFound(uint32 eid);
              error InvalidSimulationResult(uint32 eid, bytes reason);
              error CrimeFound(bytes crime);
              function getConfig(bytes[] calldata _packets, uint256[] calldata _packetMsgValues) external returns (bytes memory);
              function simulate(
                  bytes[] calldata _packets,
                  uint256[] calldata _packetMsgValues
              ) external payable returns (bytes memory);
              function buildSimulationResult() external view returns (bytes memory);
              function preCrime(
                  bytes[] calldata _packets,
                  uint256[] calldata _packetMsgValues,
                  bytes[] calldata _simulations
              ) external;
              function version() external view returns (uint64 major, uint8 minor);
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.20;
          import { Origin } from "@layerzerolabs/lz-evm-protocol-v2/contracts/interfaces/ILayerZeroEndpointV2.sol";
          import { PacketV1Codec } from "@layerzerolabs/lz-evm-protocol-v2/contracts/messagelib/libs/PacketV1Codec.sol";
          /**
           * @title InboundPacket
           * @dev Structure representing an inbound packet received by the contract.
           */
          struct InboundPacket {
              Origin origin; // Origin information of the packet.
              uint32 dstEid; // Destination endpointId of the packet.
              address receiver; // Receiver address for the packet.
              bytes32 guid; // Unique identifier of the packet.
              uint256 value; // msg.value of the packet.
              address executor; // Executor address for the packet.
              bytes message; // Message payload of the packet.
              bytes extraData; // Additional arbitrary data for the packet.
          }
          /**
           * @title PacketDecoder
           * @dev Library for decoding LayerZero packets.
           */
          library PacketDecoder {
              using PacketV1Codec for bytes;
              /**
               * @dev Decode an inbound packet from the given packet data.
               * @param _packet The packet data to decode.
               * @return packet An InboundPacket struct representing the decoded packet.
               */
              function decode(bytes calldata _packet) internal pure returns (InboundPacket memory packet) {
                  packet.origin = Origin(_packet.srcEid(), _packet.sender(), _packet.nonce());
                  packet.dstEid = _packet.dstEid();
                  packet.receiver = _packet.receiverB20();
                  packet.guid = _packet.guid();
                  packet.message = _packet.message();
              }
              /**
               * @dev Decode multiple inbound packets from the given packet data and associated message values.
               * @param _packets An array of packet data to decode.
               * @param _packetMsgValues An array of associated message values for each packet.
               * @return packets An array of InboundPacket structs representing the decoded packets.
               */
              function decode(
                  bytes[] calldata _packets,
                  uint256[] memory _packetMsgValues
              ) internal pure returns (InboundPacket[] memory packets) {
                  packets = new InboundPacket[](_packets.length);
                  for (uint256 i = 0; i < _packets.length; i++) {
                      bytes calldata packet = _packets[i];
                      packets[i] = PacketDecoder.decode(packet);
                      // @dev Allows the verifier to specify the msg.value that gets passed in lzReceive.
                      packets[i].value = _packetMsgValues[i];
                  }
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.20;
          import { Ownable } from "@openzeppelin/contracts/access/Ownable.sol";
          import { IPreCrime } from "./interfaces/IPreCrime.sol";
          import { IOAppPreCrimeSimulator, InboundPacket, Origin } from "./interfaces/IOAppPreCrimeSimulator.sol";
          /**
           * @title OAppPreCrimeSimulator
           * @dev Abstract contract serving as the base for preCrime simulation functionality in an OApp.
           */
          abstract contract OAppPreCrimeSimulator is IOAppPreCrimeSimulator, Ownable {
              // The address of the preCrime implementation.
              address public preCrime;
              /**
               * @dev Retrieves the address of the OApp contract.
               * @return The address of the OApp contract.
               *
               * @dev The simulator contract is the base contract for the OApp by default.
               * @dev If the simulator is a separate contract, override this function.
               */
              function oApp() external view virtual returns (address) {
                  return address(this);
              }
              /**
               * @dev Sets the preCrime contract address.
               * @param _preCrime The address of the preCrime contract.
               */
              function setPreCrime(address _preCrime) public virtual onlyOwner {
                  preCrime = _preCrime;
                  emit PreCrimeSet(_preCrime);
              }
              /**
               * @dev Interface for pre-crime simulations. Always reverts at the end with the simulation results.
               * @param _packets An array of InboundPacket objects representing received packets to be delivered.
               *
               * @dev WARNING: MUST revert at the end with the simulation results.
               * @dev Gives the preCrime implementation the ability to mock sending packets to the lzReceive function,
               * WITHOUT actually executing them.
               */
              function lzReceiveAndRevert(InboundPacket[] calldata _packets) public payable virtual {
                  for (uint256 i = 0; i < _packets.length; i++) {
                      InboundPacket calldata packet = _packets[i];
                      // Ignore packets that are not from trusted peers.
                      if (!isPeer(packet.origin.srcEid, packet.origin.sender)) continue;
                      // @dev Because a verifier is calling this function, it doesnt have access to executor params:
                      //  - address _executor
                      //  - bytes calldata _extraData
                      // preCrime will NOT work for OApps that rely on these two parameters inside of their _lzReceive().
                      // They are instead stubbed to default values, address(0) and bytes("")
                      // @dev Calling this.lzReceiveSimulate removes ability for assembly return 0 callstack exit,
                      // which would cause the revert to be ignored.
                      this.lzReceiveSimulate{ value: packet.value }(
                          packet.origin,
                          packet.guid,
                          packet.message,
                          packet.executor,
                          packet.extraData
                      );
                  }
                  // @dev Revert with the simulation results. msg.sender must implement IPreCrime.buildSimulationResult().
                  revert SimulationResult(IPreCrime(msg.sender).buildSimulationResult());
              }
              /**
               * @dev Is effectively an internal function because msg.sender must be address(this).
               * Allows resetting the call stack for 'internal' calls.
               * @param _origin The origin information containing the source endpoint and sender address.
               *  - srcEid: The source chain endpoint ID.
               *  - sender: The sender address on the src chain.
               *  - nonce: The nonce of the message.
               * @param _guid The unique identifier of the packet.
               * @param _message The message payload of the packet.
               * @param _executor The executor address for the packet.
               * @param _extraData Additional data for the packet.
               */
              function lzReceiveSimulate(
                  Origin calldata _origin,
                  bytes32 _guid,
                  bytes calldata _message,
                  address _executor,
                  bytes calldata _extraData
              ) external payable virtual {
                  // @dev Ensure ONLY can be called 'internally'.
                  if (msg.sender != address(this)) revert OnlySelf();
                  _lzReceiveSimulate(_origin, _guid, _message, _executor, _extraData);
              }
              /**
               * @dev Internal function to handle the OAppPreCrimeSimulator simulated receive.
               * @param _origin The origin information.
               *  - srcEid: The source chain endpoint ID.
               *  - sender: The sender address from the src chain.
               *  - nonce: The nonce of the LayerZero message.
               * @param _guid The GUID of the LayerZero message.
               * @param _message The LayerZero message.
               * @param _executor The address of the off-chain executor.
               * @param _extraData Arbitrary data passed by the msg executor.
               *
               * @dev Enables the preCrime simulator to mock sending lzReceive() messages,
               * routes the msg down from the OAppPreCrimeSimulator, and back up to the OAppReceiver.
               */
              function _lzReceiveSimulate(
                  Origin calldata _origin,
                  bytes32 _guid,
                  bytes calldata _message,
                  address _executor,
                  bytes calldata _extraData
              ) internal virtual;
              /**
               * @dev checks if the specified peer is considered 'trusted' by the OApp.
               * @param _eid The endpoint Id to check.
               * @param _peer The peer to check.
               * @return Whether the peer passed is considered 'trusted' by the OApp.
               */
              function isPeer(uint32 _eid, bytes32 _peer) public view virtual returns (bool);
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.20;
          import { MessagingReceipt, MessagingFee } from "@layerzerolabs/oapp-evm/contracts/oapp/OAppSender.sol";
          /**
           * @dev Struct representing token parameters for the OFT send() operation.
           */
          struct SendParam {
              uint32 dstEid; // Destination endpoint ID.
              bytes32 to; // Recipient address.
              uint256 amountLD; // Amount to send in local decimals.
              uint256 minAmountLD; // Minimum amount to send in local decimals.
              bytes extraOptions; // Additional options supplied by the caller to be used in the LayerZero message.
              bytes composeMsg; // The composed message for the send() operation.
              bytes oftCmd; // The OFT command to be executed, unused in default OFT implementations.
          }
          /**
           * @dev Struct representing OFT limit information.
           * @dev These amounts can change dynamically and are up the specific oft implementation.
           */
          struct OFTLimit {
              uint256 minAmountLD; // Minimum amount in local decimals that can be sent to the recipient.
              uint256 maxAmountLD; // Maximum amount in local decimals that can be sent to the recipient.
          }
          /**
           * @dev Struct representing OFT receipt information.
           */
          struct OFTReceipt {
              uint256 amountSentLD; // Amount of tokens ACTUALLY debited from the sender in local decimals.
              // @dev In non-default implementations, the amountReceivedLD COULD differ from this value.
              uint256 amountReceivedLD; // Amount of tokens to be received on the remote side.
          }
          /**
           * @dev Struct representing OFT fee details.
           * @dev Future proof mechanism to provide a standardized way to communicate fees to things like a UI.
           */
          struct OFTFeeDetail {
              int256 feeAmountLD; // Amount of the fee in local decimals.
              string description; // Description of the fee.
          }
          /**
           * @title IOFT
           * @dev Interface for the OftChain (OFT) token.
           * @dev Does not inherit ERC20 to accommodate usage by OFTAdapter as well.
           * @dev This specific interface ID is '0x02e49c2c'.
           */
          interface IOFT {
              // Custom error messages
              error InvalidLocalDecimals();
              error SlippageExceeded(uint256 amountLD, uint256 minAmountLD);
              // Events
              event OFTSent(
                  bytes32 indexed guid, // GUID of the OFT message.
                  uint32 dstEid, // Destination Endpoint ID.
                  address indexed fromAddress, // Address of the sender on the src chain.
                  uint256 amountSentLD, // Amount of tokens sent in local decimals.
                  uint256 amountReceivedLD // Amount of tokens received in local decimals.
              );
              event OFTReceived(
                  bytes32 indexed guid, // GUID of the OFT message.
                  uint32 srcEid, // Source Endpoint ID.
                  address indexed toAddress, // Address of the recipient on the dst chain.
                  uint256 amountReceivedLD // Amount of tokens received in local decimals.
              );
              /**
               * @notice Retrieves interfaceID and the version of the OFT.
               * @return interfaceId The interface ID.
               * @return version The version.
               *
               * @dev interfaceId: This specific interface ID is '0x02e49c2c'.
               * @dev version: Indicates a cross-chain compatible msg encoding with other OFTs.
               * @dev If a new feature is added to the OFT cross-chain msg encoding, the version will be incremented.
               * ie. localOFT version(x,1) CAN send messages to remoteOFT version(x,1)
               */
              function oftVersion() external view returns (bytes4 interfaceId, uint64 version);
              /**
               * @notice Retrieves the address of the token associated with the OFT.
               * @return token The address of the ERC20 token implementation.
               */
              function token() external view returns (address);
              /**
               * @notice Indicates whether the OFT contract requires approval of the 'token()' to send.
               * @return requiresApproval Needs approval of the underlying token implementation.
               *
               * @dev Allows things like wallet implementers to determine integration requirements,
               * without understanding the underlying token implementation.
               */
              function approvalRequired() external view returns (bool);
              /**
               * @notice Retrieves the shared decimals of the OFT.
               * @return sharedDecimals The shared decimals of the OFT.
               */
              function sharedDecimals() external view returns (uint8);
              /**
               * @notice Provides the fee breakdown and settings data for an OFT. Unused in the default implementation.
               * @param _sendParam The parameters for the send operation.
               * @return limit The OFT limit information.
               * @return oftFeeDetails The details of OFT fees.
               * @return receipt The OFT receipt information.
               */
              function quoteOFT(
                  SendParam calldata _sendParam
              ) external view returns (OFTLimit memory, OFTFeeDetail[] memory oftFeeDetails, OFTReceipt memory);
              /**
               * @notice Provides a quote for the send() operation.
               * @param _sendParam The parameters for the send() operation.
               * @param _payInLzToken Flag indicating whether the caller is paying in the LZ token.
               * @return fee The calculated LayerZero messaging fee from the send() operation.
               *
               * @dev MessagingFee: LayerZero msg fee
               *  - nativeFee: The native fee.
               *  - lzTokenFee: The lzToken fee.
               */
              function quoteSend(SendParam calldata _sendParam, bool _payInLzToken) external view returns (MessagingFee memory);
              /**
               * @notice Executes the send() operation.
               * @param _sendParam The parameters for the send operation.
               * @param _fee The fee information supplied by the caller.
               *      - nativeFee: The native fee.
               *      - lzTokenFee: The lzToken fee.
               * @param _refundAddress The address to receive any excess funds from fees etc. on the src.
               * @return receipt The LayerZero messaging receipt from the send() operation.
               * @return oftReceipt The OFT receipt information.
               *
               * @dev MessagingReceipt: LayerZero msg receipt
               *  - guid: The unique identifier for the sent message.
               *  - nonce: The nonce of the sent message.
               *  - fee: The LayerZero fee incurred for the message.
               */
              function send(
                  SendParam calldata _sendParam,
                  MessagingFee calldata _fee,
                  address _refundAddress
              ) external payable returns (MessagingReceipt memory, OFTReceipt memory);
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.20;
          library OFTComposeMsgCodec {
              // Offset constants for decoding composed messages
              uint8 private constant NONCE_OFFSET = 8;
              uint8 private constant SRC_EID_OFFSET = 12;
              uint8 private constant AMOUNT_LD_OFFSET = 44;
              uint8 private constant COMPOSE_FROM_OFFSET = 76;
              /**
               * @dev Encodes a OFT composed message.
               * @param _nonce The nonce value.
               * @param _srcEid The source endpoint ID.
               * @param _amountLD The amount in local decimals.
               * @param _composeMsg The composed message.
               * @return _msg The encoded Composed message.
               */
              function encode(
                  uint64 _nonce,
                  uint32 _srcEid,
                  uint256 _amountLD,
                  bytes memory _composeMsg // 0x[composeFrom][composeMsg]
              ) internal pure returns (bytes memory _msg) {
                  _msg = abi.encodePacked(_nonce, _srcEid, _amountLD, _composeMsg);
              }
              /**
               * @dev Retrieves the nonce for the composed message.
               * @param _msg The message.
               * @return The nonce value.
               */
              function nonce(bytes calldata _msg) internal pure returns (uint64) {
                  return uint64(bytes8(_msg[:NONCE_OFFSET]));
              }
              /**
               * @dev Retrieves the source endpoint ID for the composed message.
               * @param _msg The message.
               * @return The source endpoint ID.
               */
              function srcEid(bytes calldata _msg) internal pure returns (uint32) {
                  return uint32(bytes4(_msg[NONCE_OFFSET:SRC_EID_OFFSET]));
              }
              /**
               * @dev Retrieves the amount in local decimals from the composed message.
               * @param _msg The message.
               * @return The amount in local decimals.
               */
              function amountLD(bytes calldata _msg) internal pure returns (uint256) {
                  return uint256(bytes32(_msg[SRC_EID_OFFSET:AMOUNT_LD_OFFSET]));
              }
              /**
               * @dev Retrieves the composeFrom value from the composed message.
               * @param _msg The message.
               * @return The composeFrom value.
               */
              function composeFrom(bytes calldata _msg) internal pure returns (bytes32) {
                  return bytes32(_msg[AMOUNT_LD_OFFSET:COMPOSE_FROM_OFFSET]);
              }
              /**
               * @dev Retrieves the composed message.
               * @param _msg The message.
               * @return The composed message.
               */
              function composeMsg(bytes calldata _msg) internal pure returns (bytes memory) {
                  return _msg[COMPOSE_FROM_OFFSET:];
              }
              /**
               * @dev Converts an address to bytes32.
               * @param _addr The address to convert.
               * @return The bytes32 representation of the address.
               */
              function addressToBytes32(address _addr) internal pure returns (bytes32) {
                  return bytes32(uint256(uint160(_addr)));
              }
              /**
               * @dev Converts bytes32 to an address.
               * @param _b The bytes32 value to convert.
               * @return The address representation of bytes32.
               */
              function bytes32ToAddress(bytes32 _b) internal pure returns (address) {
                  return address(uint160(uint256(_b)));
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.20;
          library OFTMsgCodec {
              // Offset constants for encoding and decoding OFT messages
              uint8 private constant SEND_TO_OFFSET = 32;
              uint8 private constant SEND_AMOUNT_SD_OFFSET = 40;
              /**
               * @dev Encodes an OFT LayerZero message.
               * @param _sendTo The recipient address.
               * @param _amountShared The amount in shared decimals.
               * @param _composeMsg The composed message.
               * @return _msg The encoded message.
               * @return hasCompose A boolean indicating whether the message has a composed payload.
               */
              function encode(
                  bytes32 _sendTo,
                  uint64 _amountShared,
                  bytes memory _composeMsg
              ) internal view returns (bytes memory _msg, bool hasCompose) {
                  hasCompose = _composeMsg.length > 0;
                  // @dev Remote chains will want to know the composed function caller ie. msg.sender on the src.
                  _msg = hasCompose
                      ? abi.encodePacked(_sendTo, _amountShared, addressToBytes32(msg.sender), _composeMsg)
                      : abi.encodePacked(_sendTo, _amountShared);
              }
              /**
               * @dev Checks if the OFT message is composed.
               * @param _msg The OFT message.
               * @return A boolean indicating whether the message is composed.
               */
              function isComposed(bytes calldata _msg) internal pure returns (bool) {
                  return _msg.length > SEND_AMOUNT_SD_OFFSET;
              }
              /**
               * @dev Retrieves the recipient address from the OFT message.
               * @param _msg The OFT message.
               * @return The recipient address.
               */
              function sendTo(bytes calldata _msg) internal pure returns (bytes32) {
                  return bytes32(_msg[:SEND_TO_OFFSET]);
              }
              /**
               * @dev Retrieves the amount in shared decimals from the OFT message.
               * @param _msg The OFT message.
               * @return The amount in shared decimals.
               */
              function amountSD(bytes calldata _msg) internal pure returns (uint64) {
                  return uint64(bytes8(_msg[SEND_TO_OFFSET:SEND_AMOUNT_SD_OFFSET]));
              }
              /**
               * @dev Retrieves the composed message from the OFT message.
               * @param _msg The OFT message.
               * @return The composed message.
               */
              function composeMsg(bytes calldata _msg) internal pure returns (bytes memory) {
                  return _msg[SEND_AMOUNT_SD_OFFSET:];
              }
              /**
               * @dev Converts an address to bytes32.
               * @param _addr The address to convert.
               * @return The bytes32 representation of the address.
               */
              function addressToBytes32(address _addr) internal pure returns (bytes32) {
                  return bytes32(uint256(uint160(_addr)));
              }
              /**
               * @dev Converts bytes32 to an address.
               * @param _b The bytes32 value to convert.
               * @return The address representation of bytes32.
               */
              function bytes32ToAddress(bytes32 _b) internal pure returns (address) {
                  return address(uint160(uint256(_b)));
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.20;
          import { ERC20 } from "@openzeppelin/contracts/token/ERC20/ERC20.sol";
          import { IOFT, OFTCore } from "./OFTCore.sol";
          /**
           * @title OFT Contract
           * @dev OFT is an ERC-20 token that extends the functionality of the OFTCore contract.
           */
          abstract contract OFT is OFTCore, ERC20 {
              /**
               * @dev Constructor for the OFT contract.
               * @param _name The name of the OFT.
               * @param _symbol The symbol of the OFT.
               * @param _lzEndpoint The LayerZero endpoint address.
               * @param _delegate The delegate capable of making OApp configurations inside of the endpoint.
               */
              constructor(
                  string memory _name,
                  string memory _symbol,
                  address _lzEndpoint,
                  address _delegate
              ) ERC20(_name, _symbol) OFTCore(decimals(), _lzEndpoint, _delegate) {}
              /**
               * @dev Retrieves the address of the underlying ERC20 implementation.
               * @return The address of the OFT token.
               *
               * @dev In the case of OFT, address(this) and erc20 are the same contract.
               */
              function token() public view returns (address) {
                  return address(this);
              }
              /**
               * @notice Indicates whether the OFT contract requires approval of the 'token()' to send.
               * @return requiresApproval Needs approval of the underlying token implementation.
               *
               * @dev In the case of OFT where the contract IS the token, approval is NOT required.
               */
              function approvalRequired() external pure virtual returns (bool) {
                  return false;
              }
              /**
               * @dev Burns tokens from the sender's specified balance.
               * @param _from The address to debit the tokens from.
               * @param _amountLD The amount of tokens to send in local decimals.
               * @param _minAmountLD The minimum amount to send in local decimals.
               * @param _dstEid The destination chain ID.
               * @return amountSentLD The amount sent in local decimals.
               * @return amountReceivedLD The amount received in local decimals on the remote.
               */
              function _debit(
                  address _from,
                  uint256 _amountLD,
                  uint256 _minAmountLD,
                  uint32 _dstEid
              ) internal virtual override returns (uint256 amountSentLD, uint256 amountReceivedLD) {
                  (amountSentLD, amountReceivedLD) = _debitView(_amountLD, _minAmountLD, _dstEid);
                  // @dev In NON-default OFT, amountSentLD could be 100, with a 10% fee, the amountReceivedLD amount is 90,
                  // therefore amountSentLD CAN differ from amountReceivedLD.
                  // @dev Default OFT burns on src.
                  _burn(_from, amountSentLD);
              }
              /**
               * @dev Credits tokens to the specified address.
               * @param _to The address to credit the tokens to.
               * @param _amountLD The amount of tokens to credit in local decimals.
               * @dev _srcEid The source chain ID.
               * @return amountReceivedLD The amount of tokens ACTUALLY received in local decimals.
               */
              function _credit(
                  address _to,
                  uint256 _amountLD,
                  uint32 /*_srcEid*/
              ) internal virtual override returns (uint256 amountReceivedLD) {
                  if (_to == address(0x0)) _to = address(0xdead); // _mint(...) does not support address(0x0)
                  // @dev Default OFT mints on dst.
                  _mint(_to, _amountLD);
                  // @dev In the case of NON-default OFT, the _amountLD MIGHT not be == amountReceivedLD.
                  return _amountLD;
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.20;
          import { IERC20 } from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
          import { OApp, Origin } from "@layerzerolabs/oapp-evm/contracts/oapp/OApp.sol";
          import { OAppOptionsType3 } from "@layerzerolabs/oapp-evm/contracts/oapp/libs/OAppOptionsType3.sol";
          import { IOAppMsgInspector } from "@layerzerolabs/oapp-evm/contracts/oapp/interfaces/IOAppMsgInspector.sol";
          import { OAppPreCrimeSimulator } from "@layerzerolabs/oapp-evm/contracts/precrime/OAppPreCrimeSimulator.sol";
          import { IOFT, SendParam, OFTLimit, OFTReceipt, OFTFeeDetail, MessagingReceipt, MessagingFee } from "./interfaces/IOFT.sol";
          import { OFTMsgCodec } from "./libs/OFTMsgCodec.sol";
          import { OFTComposeMsgCodec } from "./libs/OFTComposeMsgCodec.sol";
          /**
           * @title OFTCore
           * @dev Abstract contract for the OftChain (OFT) token.
           */
          abstract contract OFTCore is IOFT, OApp, OAppPreCrimeSimulator, OAppOptionsType3 {
              using OFTMsgCodec for bytes;
              using OFTMsgCodec for bytes32;
              // @notice Provides a conversion rate when swapping between denominations of SD and LD
              //      - shareDecimals == SD == shared Decimals
              //      - localDecimals == LD == local decimals
              // @dev Considers that tokens have different decimal amounts on various chains.
              // @dev eg.
              //  For a token
              //      - locally with 4 decimals --> 1.2345 => uint(12345)
              //      - remotely with 2 decimals --> 1.23 => uint(123)
              //      - The conversion rate would be 10 ** (4 - 2) = 100
              //  @dev If you want to send 1.2345 -> (uint 12345), you CANNOT represent that value on the remote,
              //  you can only display 1.23 -> uint(123).
              //  @dev To preserve the dust that would otherwise be lost on that conversion,
              //  we need to unify a denomination that can be represented on ALL chains inside of the OFT mesh
              uint256 public immutable decimalConversionRate;
              // @notice Msg types that are used to identify the various OFT operations.
              // @dev This can be extended in child contracts for non-default oft operations
              // @dev These values are used in things like combineOptions() in OAppOptionsType3.sol.
              uint16 public constant SEND = 1;
              uint16 public constant SEND_AND_CALL = 2;
              // Address of an optional contract to inspect both 'message' and 'options'
              address public msgInspector;
              event MsgInspectorSet(address inspector);
              /**
               * @dev Constructor.
               * @param _localDecimals The decimals of the token on the local chain (this chain).
               * @param _endpoint The address of the LayerZero endpoint.
               * @param _delegate The delegate capable of making OApp configurations inside of the endpoint.
               */
              constructor(uint8 _localDecimals, address _endpoint, address _delegate) OApp(_endpoint, _delegate) {
                  if (_localDecimals < sharedDecimals()) revert InvalidLocalDecimals();
                  decimalConversionRate = 10 ** (_localDecimals - sharedDecimals());
              }
              /**
               * @notice Retrieves interfaceID and the version of the OFT.
               * @return interfaceId The interface ID.
               * @return version The version.
               *
               * @dev interfaceId: This specific interface ID is '0x02e49c2c'.
               * @dev version: Indicates a cross-chain compatible msg encoding with other OFTs.
               * @dev If a new feature is added to the OFT cross-chain msg encoding, the version will be incremented.
               * ie. localOFT version(x,1) CAN send messages to remoteOFT version(x,1)
               */
              function oftVersion() external pure virtual returns (bytes4 interfaceId, uint64 version) {
                  return (type(IOFT).interfaceId, 1);
              }
              /**
               * @dev Retrieves the shared decimals of the OFT.
               * @return The shared decimals of the OFT.
               *
               * @dev Sets an implicit cap on the amount of tokens, over uint64.max() will need some sort of outbound cap / totalSupply cap
               * Lowest common decimal denominator between chains.
               * Defaults to 6 decimal places to provide up to 18,446,744,073,709.551615 units (max uint64).
               * For tokens exceeding this totalSupply(), they will need to override the sharedDecimals function with something smaller.
               * ie. 4 sharedDecimals would be 1,844,674,407,370,955.1615
               */
              function sharedDecimals() public view virtual returns (uint8) {
                  return 6;
              }
              /**
               * @dev Sets the message inspector address for the OFT.
               * @param _msgInspector The address of the message inspector.
               *
               * @dev This is an optional contract that can be used to inspect both 'message' and 'options'.
               * @dev Set it to address(0) to disable it, or set it to a contract address to enable it.
               */
              function setMsgInspector(address _msgInspector) public virtual onlyOwner {
                  msgInspector = _msgInspector;
                  emit MsgInspectorSet(_msgInspector);
              }
              /**
               * @notice Provides the fee breakdown and settings data for an OFT. Unused in the default implementation.
               * @param _sendParam The parameters for the send operation.
               * @return oftLimit The OFT limit information.
               * @return oftFeeDetails The details of OFT fees.
               * @return oftReceipt The OFT receipt information.
               */
              function quoteOFT(
                  SendParam calldata _sendParam
              )
                  external
                  view
                  virtual
                  returns (OFTLimit memory oftLimit, OFTFeeDetail[] memory oftFeeDetails, OFTReceipt memory oftReceipt)
              {
                  uint256 minAmountLD = 0; // Unused in the default implementation.
                  uint256 maxAmountLD = IERC20(this.token()).totalSupply(); // Unused in the default implementation.
                  oftLimit = OFTLimit(minAmountLD, maxAmountLD);
                  // Unused in the default implementation; reserved for future complex fee details.
                  oftFeeDetails = new OFTFeeDetail[](0);
                  // @dev This is the same as the send() operation, but without the actual send.
                  // - amountSentLD is the amount in local decimals that would be sent from the sender.
                  // - amountReceivedLD is the amount in local decimals that will be credited to the recipient on the remote OFT instance.
                  // @dev The amountSentLD MIGHT not equal the amount the user actually receives. HOWEVER, the default does.
                  (uint256 amountSentLD, uint256 amountReceivedLD) = _debitView(
                      _sendParam.amountLD,
                      _sendParam.minAmountLD,
                      _sendParam.dstEid
                  );
                  oftReceipt = OFTReceipt(amountSentLD, amountReceivedLD);
              }
              /**
               * @notice Provides a quote for the send() operation.
               * @param _sendParam The parameters for the send() operation.
               * @param _payInLzToken Flag indicating whether the caller is paying in the LZ token.
               * @return msgFee The calculated LayerZero messaging fee from the send() operation.
               *
               * @dev MessagingFee: LayerZero msg fee
               *  - nativeFee: The native fee.
               *  - lzTokenFee: The lzToken fee.
               */
              function quoteSend(
                  SendParam calldata _sendParam,
                  bool _payInLzToken
              ) external view virtual returns (MessagingFee memory msgFee) {
                  // @dev mock the amount to receive, this is the same operation used in the send().
                  // The quote is as similar as possible to the actual send() operation.
                  (, uint256 amountReceivedLD) = _debitView(_sendParam.amountLD, _sendParam.minAmountLD, _sendParam.dstEid);
                  // @dev Builds the options and OFT message to quote in the endpoint.
                  (bytes memory message, bytes memory options) = _buildMsgAndOptions(_sendParam, amountReceivedLD);
                  // @dev Calculates the LayerZero fee for the send() operation.
                  return _quote(_sendParam.dstEid, message, options, _payInLzToken);
              }
              /**
               * @dev Executes the send operation.
               * @param _sendParam The parameters for the send operation.
               * @param _fee The calculated fee for the send() operation.
               *      - nativeFee: The native fee.
               *      - lzTokenFee: The lzToken fee.
               * @param _refundAddress The address to receive any excess funds.
               * @return msgReceipt The receipt for the send operation.
               * @return oftReceipt The OFT receipt information.
               *
               * @dev MessagingReceipt: LayerZero msg receipt
               *  - guid: The unique identifier for the sent message.
               *  - nonce: The nonce of the sent message.
               *  - fee: The LayerZero fee incurred for the message.
               */
              function send(
                  SendParam calldata _sendParam,
                  MessagingFee calldata _fee,
                  address _refundAddress
              ) external payable virtual returns (MessagingReceipt memory msgReceipt, OFTReceipt memory oftReceipt) {
                  return _send(_sendParam, _fee, _refundAddress);
              }
              /**
               * @dev Internal function to execute the send operation.
               * @param _sendParam The parameters for the send operation.
               * @param _fee The calculated fee for the send() operation.
               *      - nativeFee: The native fee.
               *      - lzTokenFee: The lzToken fee.
               * @param _refundAddress The address to receive any excess funds.
               * @return msgReceipt The receipt for the send operation.
               * @return oftReceipt The OFT receipt information.
               *
               * @dev MessagingReceipt: LayerZero msg receipt
               *  - guid: The unique identifier for the sent message.
               *  - nonce: The nonce of the sent message.
               *  - fee: The LayerZero fee incurred for the message.
               */
              function _send(
                  SendParam calldata _sendParam,
                  MessagingFee calldata _fee,
                  address _refundAddress
              ) internal virtual returns (MessagingReceipt memory msgReceipt, OFTReceipt memory oftReceipt) {
                  // @dev Applies the token transfers regarding this send() operation.
                  // - amountSentLD is the amount in local decimals that was ACTUALLY sent/debited from the sender.
                  // - amountReceivedLD is the amount in local decimals that will be received/credited to the recipient on the remote OFT instance.
                  (uint256 amountSentLD, uint256 amountReceivedLD) = _debit(
                      msg.sender,
                      _sendParam.amountLD,
                      _sendParam.minAmountLD,
                      _sendParam.dstEid
                  );
                  // @dev Builds the options and OFT message to quote in the endpoint.
                  (bytes memory message, bytes memory options) = _buildMsgAndOptions(_sendParam, amountReceivedLD);
                  // @dev Sends the message to the LayerZero endpoint and returns the LayerZero msg receipt.
                  msgReceipt = _lzSend(_sendParam.dstEid, message, options, _fee, _refundAddress);
                  // @dev Formulate the OFT receipt.
                  oftReceipt = OFTReceipt(amountSentLD, amountReceivedLD);
                  emit OFTSent(msgReceipt.guid, _sendParam.dstEid, msg.sender, amountSentLD, amountReceivedLD);
              }
              /**
               * @dev Internal function to build the message and options.
               * @param _sendParam The parameters for the send() operation.
               * @param _amountLD The amount in local decimals.
               * @return message The encoded message.
               * @return options The encoded options.
               */
              function _buildMsgAndOptions(
                  SendParam calldata _sendParam,
                  uint256 _amountLD
              ) internal view virtual returns (bytes memory message, bytes memory options) {
                  bool hasCompose;
                  // @dev This generated message has the msg.sender encoded into the payload so the remote knows who the caller is.
                  (message, hasCompose) = OFTMsgCodec.encode(
                      _sendParam.to,
                      _toSD(_amountLD),
                      // @dev Must be include a non empty bytes if you want to compose, EVEN if you dont need it on the remote.
                      // EVEN if you dont require an arbitrary payload to be sent... eg. '0x01'
                      _sendParam.composeMsg
                  );
                  // @dev Change the msg type depending if its composed or not.
                  uint16 msgType = hasCompose ? SEND_AND_CALL : SEND;
                  // @dev Combine the callers _extraOptions with the enforced options via the OAppOptionsType3.
                  options = combineOptions(_sendParam.dstEid, msgType, _sendParam.extraOptions);
                  // @dev Optionally inspect the message and options depending if the OApp owner has set a msg inspector.
                  // @dev If it fails inspection, needs to revert in the implementation. ie. does not rely on return boolean
                  address inspector = msgInspector; // caches the msgInspector to avoid potential double storage read
                  if (inspector != address(0)) IOAppMsgInspector(inspector).inspect(message, options);
              }
              /**
               * @dev Internal function to handle the receive on the LayerZero endpoint.
               * @param _origin The origin information.
               *  - srcEid: The source chain endpoint ID.
               *  - sender: The sender address from the src chain.
               *  - nonce: The nonce of the LayerZero message.
               * @param _guid The unique identifier for the received LayerZero message.
               * @param _message The encoded message.
               * @dev _executor The address of the executor.
               * @dev _extraData Additional data.
               */
              function _lzReceive(
                  Origin calldata _origin,
                  bytes32 _guid,
                  bytes calldata _message,
                  address /*_executor*/, // @dev unused in the default implementation.
                  bytes calldata /*_extraData*/ // @dev unused in the default implementation.
              ) internal virtual override {
                  // @dev The src sending chain doesnt know the address length on this chain (potentially non-evm)
                  // Thus everything is bytes32() encoded in flight.
                  address toAddress = _message.sendTo().bytes32ToAddress();
                  // @dev Credit the amountLD to the recipient and return the ACTUAL amount the recipient received in local decimals
                  uint256 amountReceivedLD = _credit(toAddress, _toLD(_message.amountSD()), _origin.srcEid);
                  if (_message.isComposed()) {
                      // @dev Proprietary composeMsg format for the OFT.
                      bytes memory composeMsg = OFTComposeMsgCodec.encode(
                          _origin.nonce,
                          _origin.srcEid,
                          amountReceivedLD,
                          _message.composeMsg()
                      );
                      // @dev Stores the lzCompose payload that will be executed in a separate tx.
                      // Standardizes functionality for executing arbitrary contract invocation on some non-evm chains.
                      // @dev The off-chain executor will listen and process the msg based on the src-chain-callers compose options passed.
                      // @dev The index is used when a OApp needs to compose multiple msgs on lzReceive.
                      // For default OFT implementation there is only 1 compose msg per lzReceive, thus its always 0.
                      endpoint.sendCompose(toAddress, _guid, 0 /* the index of the composed message*/, composeMsg);
                  }
                  emit OFTReceived(_guid, _origin.srcEid, toAddress, amountReceivedLD);
              }
              /**
               * @dev Internal function to handle the OAppPreCrimeSimulator simulated receive.
               * @param _origin The origin information.
               *  - srcEid: The source chain endpoint ID.
               *  - sender: The sender address from the src chain.
               *  - nonce: The nonce of the LayerZero message.
               * @param _guid The unique identifier for the received LayerZero message.
               * @param _message The LayerZero message.
               * @param _executor The address of the off-chain executor.
               * @param _extraData Arbitrary data passed by the msg executor.
               *
               * @dev Enables the preCrime simulator to mock sending lzReceive() messages,
               * routes the msg down from the OAppPreCrimeSimulator, and back up to the OAppReceiver.
               */
              function _lzReceiveSimulate(
                  Origin calldata _origin,
                  bytes32 _guid,
                  bytes calldata _message,
                  address _executor,
                  bytes calldata _extraData
              ) internal virtual override {
                  _lzReceive(_origin, _guid, _message, _executor, _extraData);
              }
              /**
               * @dev Check if the peer is considered 'trusted' by the OApp.
               * @param _eid The endpoint ID to check.
               * @param _peer The peer to check.
               * @return Whether the peer passed is considered 'trusted' by the OApp.
               *
               * @dev Enables OAppPreCrimeSimulator to check whether a potential Inbound Packet is from a trusted source.
               */
              function isPeer(uint32 _eid, bytes32 _peer) public view virtual override returns (bool) {
                  return peers[_eid] == _peer;
              }
              /**
               * @dev Internal function to remove dust from the given local decimal amount.
               * @param _amountLD The amount in local decimals.
               * @return amountLD The amount after removing dust.
               *
               * @dev Prevents the loss of dust when moving amounts between chains with different decimals.
               * @dev eg. uint(123) with a conversion rate of 100 becomes uint(100).
               */
              function _removeDust(uint256 _amountLD) internal view virtual returns (uint256 amountLD) {
                  return (_amountLD / decimalConversionRate) * decimalConversionRate;
              }
              /**
               * @dev Internal function to convert an amount from shared decimals into local decimals.
               * @param _amountSD The amount in shared decimals.
               * @return amountLD The amount in local decimals.
               */
              function _toLD(uint64 _amountSD) internal view virtual returns (uint256 amountLD) {
                  return _amountSD * decimalConversionRate;
              }
              /**
               * @dev Internal function to convert an amount from local decimals into shared decimals.
               * @param _amountLD The amount in local decimals.
               * @return amountSD The amount in shared decimals.
               */
              function _toSD(uint256 _amountLD) internal view virtual returns (uint64 amountSD) {
                  return uint64(_amountLD / decimalConversionRate);
              }
              /**
               * @dev Internal function to mock the amount mutation from a OFT debit() operation.
               * @param _amountLD The amount to send in local decimals.
               * @param _minAmountLD The minimum amount to send in local decimals.
               * @dev _dstEid The destination endpoint ID.
               * @return amountSentLD The amount sent, in local decimals.
               * @return amountReceivedLD The amount to be received on the remote chain, in local decimals.
               *
               * @dev This is where things like fees would be calculated and deducted from the amount to be received on the remote.
               */
              function _debitView(
                  uint256 _amountLD,
                  uint256 _minAmountLD,
                  uint32 /*_dstEid*/
              ) internal view virtual returns (uint256 amountSentLD, uint256 amountReceivedLD) {
                  // @dev Remove the dust so nothing is lost on the conversion between chains with different decimals for the token.
                  amountSentLD = _removeDust(_amountLD);
                  // @dev The amount to send is the same as amount received in the default implementation.
                  amountReceivedLD = amountSentLD;
                  // @dev Check for slippage.
                  if (amountReceivedLD < _minAmountLD) {
                      revert SlippageExceeded(amountReceivedLD, _minAmountLD);
                  }
              }
              /**
               * @dev Internal function to perform a debit operation.
               * @param _from The address to debit.
               * @param _amountLD The amount to send in local decimals.
               * @param _minAmountLD The minimum amount to send in local decimals.
               * @param _dstEid The destination endpoint ID.
               * @return amountSentLD The amount sent in local decimals.
               * @return amountReceivedLD The amount received in local decimals on the remote.
               *
               * @dev Defined here but are intended to be overriden depending on the OFT implementation.
               * @dev Depending on OFT implementation the _amountLD could differ from the amountReceivedLD.
               */
              function _debit(
                  address _from,
                  uint256 _amountLD,
                  uint256 _minAmountLD,
                  uint32 _dstEid
              ) internal virtual returns (uint256 amountSentLD, uint256 amountReceivedLD);
              /**
               * @dev Internal function to perform a credit operation.
               * @param _to The address to credit.
               * @param _amountLD The amount to credit in local decimals.
               * @param _srcEid The source endpoint ID.
               * @return amountReceivedLD The amount ACTUALLY received in local decimals.
               *
               * @dev Defined here but are intended to be overriden depending on the OFT implementation.
               * @dev Depending on OFT implementation the _amountLD could differ from the amountReceivedLD.
               */
              function _credit(
                  address _to,
                  uint256 _amountLD,
                  uint32 _srcEid
              ) internal virtual returns (uint256 amountReceivedLD);
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.9.0) (access/AccessControl.sol)
          pragma solidity ^0.8.0;
          import "./IAccessControl.sol";
          import "../utils/Context.sol";
          import "../utils/Strings.sol";
          import "../utils/introspection/ERC165.sol";
          /**
           * @dev Contract module that allows children to implement role-based access
           * control mechanisms. This is a lightweight version that doesn't allow enumerating role
           * members except through off-chain means by accessing the contract event logs. Some
           * applications may benefit from on-chain enumerability, for those cases see
           * {AccessControlEnumerable}.
           *
           * Roles are referred to by their `bytes32` identifier. These should be exposed
           * in the external API and be unique. The best way to achieve this is by
           * using `public constant` hash digests:
           *
           * ```solidity
           * bytes32 public constant MY_ROLE = keccak256("MY_ROLE");
           * ```
           *
           * Roles can be used to represent a set of permissions. To restrict access to a
           * function call, use {hasRole}:
           *
           * ```solidity
           * function foo() public {
           *     require(hasRole(MY_ROLE, msg.sender));
           *     ...
           * }
           * ```
           *
           * Roles can be granted and revoked dynamically via the {grantRole} and
           * {revokeRole} functions. Each role has an associated admin role, and only
           * accounts that have a role's admin role can call {grantRole} and {revokeRole}.
           *
           * By default, the admin role for all roles is `DEFAULT_ADMIN_ROLE`, which means
           * that only accounts with this role will be able to grant or revoke other
           * roles. More complex role relationships can be created by using
           * {_setRoleAdmin}.
           *
           * WARNING: The `DEFAULT_ADMIN_ROLE` is also its own admin: it has permission to
           * grant and revoke this role. Extra precautions should be taken to secure
           * accounts that have been granted it. We recommend using {AccessControlDefaultAdminRules}
           * to enforce additional security measures for this role.
           */
          abstract contract AccessControl is Context, IAccessControl, ERC165 {
              struct RoleData {
                  mapping(address => bool) members;
                  bytes32 adminRole;
              }
              mapping(bytes32 => RoleData) private _roles;
              bytes32 public constant DEFAULT_ADMIN_ROLE = 0x00;
              /**
               * @dev Modifier that checks that an account has a specific role. Reverts
               * with a standardized message including the required role.
               *
               * The format of the revert reason is given by the following regular expression:
               *
               *  /^AccessControl: account (0x[0-9a-f]{40}) is missing role (0x[0-9a-f]{64})$/
               *
               * _Available since v4.1._
               */
              modifier onlyRole(bytes32 role) {
                  _checkRole(role);
                  _;
              }
              /**
               * @dev See {IERC165-supportsInterface}.
               */
              function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
                  return interfaceId == type(IAccessControl).interfaceId || super.supportsInterface(interfaceId);
              }
              /**
               * @dev Returns `true` if `account` has been granted `role`.
               */
              function hasRole(bytes32 role, address account) public view virtual override returns (bool) {
                  return _roles[role].members[account];
              }
              /**
               * @dev Revert with a standard message if `_msgSender()` is missing `role`.
               * Overriding this function changes the behavior of the {onlyRole} modifier.
               *
               * Format of the revert message is described in {_checkRole}.
               *
               * _Available since v4.6._
               */
              function _checkRole(bytes32 role) internal view virtual {
                  _checkRole(role, _msgSender());
              }
              /**
               * @dev Revert with a standard message if `account` is missing `role`.
               *
               * The format of the revert reason is given by the following regular expression:
               *
               *  /^AccessControl: account (0x[0-9a-f]{40}) is missing role (0x[0-9a-f]{64})$/
               */
              function _checkRole(bytes32 role, address account) internal view virtual {
                  if (!hasRole(role, account)) {
                      revert(
                          string(
                              abi.encodePacked(
                                  "AccessControl: account ",
                                  Strings.toHexString(account),
                                  " is missing role ",
                                  Strings.toHexString(uint256(role), 32)
                              )
                          )
                      );
                  }
              }
              /**
               * @dev Returns the admin role that controls `role`. See {grantRole} and
               * {revokeRole}.
               *
               * To change a role's admin, use {_setRoleAdmin}.
               */
              function getRoleAdmin(bytes32 role) public view virtual override returns (bytes32) {
                  return _roles[role].adminRole;
              }
              /**
               * @dev Grants `role` to `account`.
               *
               * If `account` had not been already granted `role`, emits a {RoleGranted}
               * event.
               *
               * Requirements:
               *
               * - the caller must have ``role``'s admin role.
               *
               * May emit a {RoleGranted} event.
               */
              function grantRole(bytes32 role, address account) public virtual override onlyRole(getRoleAdmin(role)) {
                  _grantRole(role, account);
              }
              /**
               * @dev Revokes `role` from `account`.
               *
               * If `account` had been granted `role`, emits a {RoleRevoked} event.
               *
               * Requirements:
               *
               * - the caller must have ``role``'s admin role.
               *
               * May emit a {RoleRevoked} event.
               */
              function revokeRole(bytes32 role, address account) public virtual override onlyRole(getRoleAdmin(role)) {
                  _revokeRole(role, account);
              }
              /**
               * @dev Revokes `role` from the calling account.
               *
               * Roles are often managed via {grantRole} and {revokeRole}: this function's
               * purpose is to provide a mechanism for accounts to lose their privileges
               * if they are compromised (such as when a trusted device is misplaced).
               *
               * If the calling account had been revoked `role`, emits a {RoleRevoked}
               * event.
               *
               * Requirements:
               *
               * - the caller must be `account`.
               *
               * May emit a {RoleRevoked} event.
               */
              function renounceRole(bytes32 role, address account) public virtual override {
                  require(account == _msgSender(), "AccessControl: can only renounce roles for self");
                  _revokeRole(role, account);
              }
              /**
               * @dev Grants `role` to `account`.
               *
               * If `account` had not been already granted `role`, emits a {RoleGranted}
               * event. Note that unlike {grantRole}, this function doesn't perform any
               * checks on the calling account.
               *
               * May emit a {RoleGranted} event.
               *
               * [WARNING]
               * ====
               * This function should only be called from the constructor when setting
               * up the initial roles for the system.
               *
               * Using this function in any other way is effectively circumventing the admin
               * system imposed by {AccessControl}.
               * ====
               *
               * NOTE: This function is deprecated in favor of {_grantRole}.
               */
              function _setupRole(bytes32 role, address account) internal virtual {
                  _grantRole(role, account);
              }
              /**
               * @dev Sets `adminRole` as ``role``'s admin role.
               *
               * Emits a {RoleAdminChanged} event.
               */
              function _setRoleAdmin(bytes32 role, bytes32 adminRole) internal virtual {
                  bytes32 previousAdminRole = getRoleAdmin(role);
                  _roles[role].adminRole = adminRole;
                  emit RoleAdminChanged(role, previousAdminRole, adminRole);
              }
              /**
               * @dev Grants `role` to `account`.
               *
               * Internal function without access restriction.
               *
               * May emit a {RoleGranted} event.
               */
              function _grantRole(bytes32 role, address account) internal virtual {
                  if (!hasRole(role, account)) {
                      _roles[role].members[account] = true;
                      emit RoleGranted(role, account, _msgSender());
                  }
              }
              /**
               * @dev Revokes `role` from `account`.
               *
               * Internal function without access restriction.
               *
               * May emit a {RoleRevoked} event.
               */
              function _revokeRole(bytes32 role, address account) internal virtual {
                  if (hasRole(role, account)) {
                      _roles[role].members[account] = false;
                      emit RoleRevoked(role, account, _msgSender());
                  }
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts v4.4.1 (access/IAccessControl.sol)
          pragma solidity ^0.8.0;
          /**
           * @dev External interface of AccessControl declared to support ERC165 detection.
           */
          interface IAccessControl {
              /**
               * @dev Emitted when `newAdminRole` is set as ``role``'s admin role, replacing `previousAdminRole`
               *
               * `DEFAULT_ADMIN_ROLE` is the starting admin for all roles, despite
               * {RoleAdminChanged} not being emitted signaling this.
               *
               * _Available since v3.1._
               */
              event RoleAdminChanged(bytes32 indexed role, bytes32 indexed previousAdminRole, bytes32 indexed newAdminRole);
              /**
               * @dev Emitted when `account` is granted `role`.
               *
               * `sender` is the account that originated the contract call, an admin role
               * bearer except when using {AccessControl-_setupRole}.
               */
              event RoleGranted(bytes32 indexed role, address indexed account, address indexed sender);
              /**
               * @dev Emitted when `account` is revoked `role`.
               *
               * `sender` is the account that originated the contract call:
               *   - if using `revokeRole`, it is the admin role bearer
               *   - if using `renounceRole`, it is the role bearer (i.e. `account`)
               */
              event RoleRevoked(bytes32 indexed role, address indexed account, address indexed sender);
              /**
               * @dev Returns `true` if `account` has been granted `role`.
               */
              function hasRole(bytes32 role, address account) external view returns (bool);
              /**
               * @dev Returns the admin role that controls `role`. See {grantRole} and
               * {revokeRole}.
               *
               * To change a role's admin, use {AccessControl-_setRoleAdmin}.
               */
              function getRoleAdmin(bytes32 role) external view returns (bytes32);
              /**
               * @dev Grants `role` to `account`.
               *
               * If `account` had not been already granted `role`, emits a {RoleGranted}
               * event.
               *
               * Requirements:
               *
               * - the caller must have ``role``'s admin role.
               */
              function grantRole(bytes32 role, address account) external;
              /**
               * @dev Revokes `role` from `account`.
               *
               * If `account` had been granted `role`, emits a {RoleRevoked} event.
               *
               * Requirements:
               *
               * - the caller must have ``role``'s admin role.
               */
              function revokeRole(bytes32 role, address account) external;
              /**
               * @dev Revokes `role` from the calling account.
               *
               * Roles are often managed via {grantRole} and {revokeRole}: this function's
               * purpose is to provide a mechanism for accounts to lose their privileges
               * if they are compromised (such as when a trusted device is misplaced).
               *
               * If the calling account had been granted `role`, emits a {RoleRevoked}
               * event.
               *
               * Requirements:
               *
               * - the caller must be `account`.
               */
              function renounceRole(bytes32 role, address account) external;
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.9.0) (access/Ownable.sol)
          pragma solidity ^0.8.0;
          import "../utils/Context.sol";
          /**
           * @dev Contract module which provides a basic access control mechanism, where
           * there is an account (an owner) that can be granted exclusive access to
           * specific functions.
           *
           * By default, the owner account will be the one that deploys the contract. This
           * can later be changed with {transferOwnership}.
           *
           * This module is used through inheritance. It will make available the modifier
           * `onlyOwner`, which can be applied to your functions to restrict their use to
           * the owner.
           */
          abstract contract Ownable is Context {
              address private _owner;
              event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
              /**
               * @dev Initializes the contract setting the deployer as the initial owner.
               */
              constructor() {
                  _transferOwnership(_msgSender());
              }
              /**
               * @dev Throws if called by any account other than the owner.
               */
              modifier onlyOwner() {
                  _checkOwner();
                  _;
              }
              /**
               * @dev Returns the address of the current owner.
               */
              function owner() public view virtual returns (address) {
                  return _owner;
              }
              /**
               * @dev Throws if the sender is not the owner.
               */
              function _checkOwner() internal view virtual {
                  require(owner() == _msgSender(), "Ownable: caller is not the owner");
              }
              /**
               * @dev Leaves the contract without owner. It will not be possible to call
               * `onlyOwner` functions. Can only be called by the current owner.
               *
               * NOTE: Renouncing ownership will leave the contract without an owner,
               * thereby disabling any functionality that is only available to the owner.
               */
              function renounceOwnership() public virtual onlyOwner {
                  _transferOwnership(address(0));
              }
              /**
               * @dev Transfers ownership of the contract to a new account (`newOwner`).
               * Can only be called by the current owner.
               */
              function transferOwnership(address newOwner) public virtual onlyOwner {
                  require(newOwner != address(0), "Ownable: new owner is the zero address");
                  _transferOwnership(newOwner);
              }
              /**
               * @dev Transfers ownership of the contract to a new account (`newOwner`).
               * Internal function without access restriction.
               */
              function _transferOwnership(address newOwner) internal virtual {
                  address oldOwner = _owner;
                  _owner = newOwner;
                  emit OwnershipTransferred(oldOwner, newOwner);
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.9.0) (security/ReentrancyGuard.sol)
          pragma solidity ^0.8.0;
          /**
           * @dev Contract module that helps prevent reentrant calls to a function.
           *
           * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
           * available, which can be applied to functions to make sure there are no nested
           * (reentrant) calls to them.
           *
           * Note that because there is a single `nonReentrant` guard, functions marked as
           * `nonReentrant` may not call one another. This can be worked around by making
           * those functions `private`, and then adding `external` `nonReentrant` entry
           * points to them.
           *
           * TIP: If you would like to learn more about reentrancy and alternative ways
           * to protect against it, check out our blog post
           * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
           */
          abstract contract ReentrancyGuard {
              // Booleans are more expensive than uint256 or any type that takes up a full
              // word because each write operation emits an extra SLOAD to first read the
              // slot's contents, replace the bits taken up by the boolean, and then write
              // back. This is the compiler's defense against contract upgrades and
              // pointer aliasing, and it cannot be disabled.
              // The values being non-zero value makes deployment a bit more expensive,
              // but in exchange the refund on every call to nonReentrant will be lower in
              // amount. Since refunds are capped to a percentage of the total
              // transaction's gas, it is best to keep them low in cases like this one, to
              // increase the likelihood of the full refund coming into effect.
              uint256 private constant _NOT_ENTERED = 1;
              uint256 private constant _ENTERED = 2;
              uint256 private _status;
              constructor() {
                  _status = _NOT_ENTERED;
              }
              /**
               * @dev Prevents a contract from calling itself, directly or indirectly.
               * Calling a `nonReentrant` function from another `nonReentrant`
               * function is not supported. It is possible to prevent this from happening
               * by making the `nonReentrant` function external, and making it call a
               * `private` function that does the actual work.
               */
              modifier nonReentrant() {
                  _nonReentrantBefore();
                  _;
                  _nonReentrantAfter();
              }
              function _nonReentrantBefore() private {
                  // On the first call to nonReentrant, _status will be _NOT_ENTERED
                  require(_status != _ENTERED, "ReentrancyGuard: reentrant call");
                  // Any calls to nonReentrant after this point will fail
                  _status = _ENTERED;
              }
              function _nonReentrantAfter() private {
                  // By storing the original value once again, a refund is triggered (see
                  // https://eips.ethereum.org/EIPS/eip-2200)
                  _status = _NOT_ENTERED;
              }
              /**
               * @dev Returns true if the reentrancy guard is currently set to "entered", which indicates there is a
               * `nonReentrant` function in the call stack.
               */
              function _reentrancyGuardEntered() internal view returns (bool) {
                  return _status == _ENTERED;
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/ERC20.sol)
          pragma solidity ^0.8.0;
          import "./IERC20.sol";
          import "./extensions/IERC20Metadata.sol";
          import "../../utils/Context.sol";
          /**
           * @dev Implementation of the {IERC20} interface.
           *
           * This implementation is agnostic to the way tokens are created. This means
           * that a supply mechanism has to be added in a derived contract using {_mint}.
           * For a generic mechanism see {ERC20PresetMinterPauser}.
           *
           * TIP: For a detailed writeup see our guide
           * https://forum.openzeppelin.com/t/how-to-implement-erc20-supply-mechanisms/226[How
           * to implement supply mechanisms].
           *
           * The default value of {decimals} is 18. To change this, you should override
           * this function so it returns a different value.
           *
           * We have followed general OpenZeppelin Contracts guidelines: functions revert
           * instead returning `false` on failure. This behavior is nonetheless
           * conventional and does not conflict with the expectations of ERC20
           * applications.
           *
           * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
           * This allows applications to reconstruct the allowance for all accounts just
           * by listening to said events. Other implementations of the EIP may not emit
           * these events, as it isn't required by the specification.
           *
           * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
           * functions have been added to mitigate the well-known issues around setting
           * allowances. See {IERC20-approve}.
           */
          contract ERC20 is Context, IERC20, IERC20Metadata {
              mapping(address => uint256) private _balances;
              mapping(address => mapping(address => uint256)) private _allowances;
              uint256 private _totalSupply;
              string private _name;
              string private _symbol;
              /**
               * @dev Sets the values for {name} and {symbol}.
               *
               * All two of these values are immutable: they can only be set once during
               * construction.
               */
              constructor(string memory name_, string memory symbol_) {
                  _name = name_;
                  _symbol = symbol_;
              }
              /**
               * @dev Returns the name of the token.
               */
              function name() public view virtual override returns (string memory) {
                  return _name;
              }
              /**
               * @dev Returns the symbol of the token, usually a shorter version of the
               * name.
               */
              function symbol() public view virtual override returns (string memory) {
                  return _symbol;
              }
              /**
               * @dev Returns the number of decimals used to get its user representation.
               * For example, if `decimals` equals `2`, a balance of `505` tokens should
               * be displayed to a user as `5.05` (`505 / 10 ** 2`).
               *
               * Tokens usually opt for a value of 18, imitating the relationship between
               * Ether and Wei. This is the default value returned by this function, unless
               * it's overridden.
               *
               * NOTE: This information is only used for _display_ purposes: it in
               * no way affects any of the arithmetic of the contract, including
               * {IERC20-balanceOf} and {IERC20-transfer}.
               */
              function decimals() public view virtual override returns (uint8) {
                  return 18;
              }
              /**
               * @dev See {IERC20-totalSupply}.
               */
              function totalSupply() public view virtual override returns (uint256) {
                  return _totalSupply;
              }
              /**
               * @dev See {IERC20-balanceOf}.
               */
              function balanceOf(address account) public view virtual override returns (uint256) {
                  return _balances[account];
              }
              /**
               * @dev See {IERC20-transfer}.
               *
               * Requirements:
               *
               * - `to` cannot be the zero address.
               * - the caller must have a balance of at least `amount`.
               */
              function transfer(address to, uint256 amount) public virtual override returns (bool) {
                  address owner = _msgSender();
                  _transfer(owner, to, amount);
                  return true;
              }
              /**
               * @dev See {IERC20-allowance}.
               */
              function allowance(address owner, address spender) public view virtual override returns (uint256) {
                  return _allowances[owner][spender];
              }
              /**
               * @dev See {IERC20-approve}.
               *
               * NOTE: If `amount` is the maximum `uint256`, the allowance is not updated on
               * `transferFrom`. This is semantically equivalent to an infinite approval.
               *
               * Requirements:
               *
               * - `spender` cannot be the zero address.
               */
              function approve(address spender, uint256 amount) public virtual override returns (bool) {
                  address owner = _msgSender();
                  _approve(owner, spender, amount);
                  return true;
              }
              /**
               * @dev See {IERC20-transferFrom}.
               *
               * Emits an {Approval} event indicating the updated allowance. This is not
               * required by the EIP. See the note at the beginning of {ERC20}.
               *
               * NOTE: Does not update the allowance if the current allowance
               * is the maximum `uint256`.
               *
               * Requirements:
               *
               * - `from` and `to` cannot be the zero address.
               * - `from` must have a balance of at least `amount`.
               * - the caller must have allowance for ``from``'s tokens of at least
               * `amount`.
               */
              function transferFrom(address from, address to, uint256 amount) public virtual override returns (bool) {
                  address spender = _msgSender();
                  _spendAllowance(from, spender, amount);
                  _transfer(from, to, amount);
                  return true;
              }
              /**
               * @dev Atomically increases the allowance granted to `spender` by the caller.
               *
               * This is an alternative to {approve} that can be used as a mitigation for
               * problems described in {IERC20-approve}.
               *
               * Emits an {Approval} event indicating the updated allowance.
               *
               * Requirements:
               *
               * - `spender` cannot be the zero address.
               */
              function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
                  address owner = _msgSender();
                  _approve(owner, spender, allowance(owner, spender) + addedValue);
                  return true;
              }
              /**
               * @dev Atomically decreases the allowance granted to `spender` by the caller.
               *
               * This is an alternative to {approve} that can be used as a mitigation for
               * problems described in {IERC20-approve}.
               *
               * Emits an {Approval} event indicating the updated allowance.
               *
               * Requirements:
               *
               * - `spender` cannot be the zero address.
               * - `spender` must have allowance for the caller of at least
               * `subtractedValue`.
               */
              function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
                  address owner = _msgSender();
                  uint256 currentAllowance = allowance(owner, spender);
                  require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
                  unchecked {
                      _approve(owner, spender, currentAllowance - subtractedValue);
                  }
                  return true;
              }
              /**
               * @dev Moves `amount` of tokens from `from` to `to`.
               *
               * This internal function is equivalent to {transfer}, and can be used to
               * e.g. implement automatic token fees, slashing mechanisms, etc.
               *
               * Emits a {Transfer} event.
               *
               * Requirements:
               *
               * - `from` cannot be the zero address.
               * - `to` cannot be the zero address.
               * - `from` must have a balance of at least `amount`.
               */
              function _transfer(address from, address to, uint256 amount) internal virtual {
                  require(from != address(0), "ERC20: transfer from the zero address");
                  require(to != address(0), "ERC20: transfer to the zero address");
                  _beforeTokenTransfer(from, to, amount);
                  uint256 fromBalance = _balances[from];
                  require(fromBalance >= amount, "ERC20: transfer amount exceeds balance");
                  unchecked {
                      _balances[from] = fromBalance - amount;
                      // Overflow not possible: the sum of all balances is capped by totalSupply, and the sum is preserved by
                      // decrementing then incrementing.
                      _balances[to] += amount;
                  }
                  emit Transfer(from, to, amount);
                  _afterTokenTransfer(from, to, amount);
              }
              /** @dev Creates `amount` tokens and assigns them to `account`, increasing
               * the total supply.
               *
               * Emits a {Transfer} event with `from` set to the zero address.
               *
               * Requirements:
               *
               * - `account` cannot be the zero address.
               */
              function _mint(address account, uint256 amount) internal virtual {
                  require(account != address(0), "ERC20: mint to the zero address");
                  _beforeTokenTransfer(address(0), account, amount);
                  _totalSupply += amount;
                  unchecked {
                      // Overflow not possible: balance + amount is at most totalSupply + amount, which is checked above.
                      _balances[account] += amount;
                  }
                  emit Transfer(address(0), account, amount);
                  _afterTokenTransfer(address(0), account, amount);
              }
              /**
               * @dev Destroys `amount` tokens from `account`, reducing the
               * total supply.
               *
               * Emits a {Transfer} event with `to` set to the zero address.
               *
               * Requirements:
               *
               * - `account` cannot be the zero address.
               * - `account` must have at least `amount` tokens.
               */
              function _burn(address account, uint256 amount) internal virtual {
                  require(account != address(0), "ERC20: burn from the zero address");
                  _beforeTokenTransfer(account, address(0), amount);
                  uint256 accountBalance = _balances[account];
                  require(accountBalance >= amount, "ERC20: burn amount exceeds balance");
                  unchecked {
                      _balances[account] = accountBalance - amount;
                      // Overflow not possible: amount <= accountBalance <= totalSupply.
                      _totalSupply -= amount;
                  }
                  emit Transfer(account, address(0), amount);
                  _afterTokenTransfer(account, address(0), amount);
              }
              /**
               * @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.
               *
               * This internal function is equivalent to `approve`, and can be used to
               * e.g. set automatic allowances for certain subsystems, etc.
               *
               * Emits an {Approval} event.
               *
               * Requirements:
               *
               * - `owner` cannot be the zero address.
               * - `spender` cannot be the zero address.
               */
              function _approve(address owner, address spender, uint256 amount) internal virtual {
                  require(owner != address(0), "ERC20: approve from the zero address");
                  require(spender != address(0), "ERC20: approve to the zero address");
                  _allowances[owner][spender] = amount;
                  emit Approval(owner, spender, amount);
              }
              /**
               * @dev Updates `owner` s allowance for `spender` based on spent `amount`.
               *
               * Does not update the allowance amount in case of infinite allowance.
               * Revert if not enough allowance is available.
               *
               * Might emit an {Approval} event.
               */
              function _spendAllowance(address owner, address spender, uint256 amount) internal virtual {
                  uint256 currentAllowance = allowance(owner, spender);
                  if (currentAllowance != type(uint256).max) {
                      require(currentAllowance >= amount, "ERC20: insufficient allowance");
                      unchecked {
                          _approve(owner, spender, currentAllowance - amount);
                      }
                  }
              }
              /**
               * @dev Hook that is called before any transfer of tokens. This includes
               * minting and burning.
               *
               * Calling conditions:
               *
               * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
               * will be transferred to `to`.
               * - when `from` is zero, `amount` tokens will be minted for `to`.
               * - when `to` is zero, `amount` of ``from``'s tokens will be burned.
               * - `from` and `to` are never both zero.
               *
               * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
               */
              function _beforeTokenTransfer(address from, address to, uint256 amount) internal virtual {}
              /**
               * @dev Hook that is called after any transfer of tokens. This includes
               * minting and burning.
               *
               * Calling conditions:
               *
               * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
               * has been transferred to `to`.
               * - when `from` is zero, `amount` tokens have been minted for `to`.
               * - when `to` is zero, `amount` of ``from``'s tokens have been burned.
               * - `from` and `to` are never both zero.
               *
               * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
               */
              function _afterTokenTransfer(address from, address to, uint256 amount) internal virtual {}
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.5.0) (token/ERC20/extensions/ERC20Burnable.sol)
          pragma solidity ^0.8.0;
          import "../ERC20.sol";
          import "../../../utils/Context.sol";
          /**
           * @dev Extension of {ERC20} that allows token holders to destroy both their own
           * tokens and those that they have an allowance for, in a way that can be
           * recognized off-chain (via event analysis).
           */
          abstract contract ERC20Burnable is Context, ERC20 {
              /**
               * @dev Destroys `amount` tokens from the caller.
               *
               * See {ERC20-_burn}.
               */
              function burn(uint256 amount) public virtual {
                  _burn(_msgSender(), amount);
              }
              /**
               * @dev Destroys `amount` tokens from `account`, deducting from the caller's
               * allowance.
               *
               * See {ERC20-_burn} and {ERC20-allowance}.
               *
               * Requirements:
               *
               * - the caller must have allowance for ``accounts``'s tokens of at least
               * `amount`.
               */
              function burnFrom(address account, uint256 amount) public virtual {
                  _spendAllowance(account, _msgSender(), amount);
                  _burn(account, amount);
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/IERC20Metadata.sol)
          pragma solidity ^0.8.0;
          import "../IERC20.sol";
          /**
           * @dev Interface for the optional metadata functions from the ERC20 standard.
           *
           * _Available since v4.1._
           */
          interface IERC20Metadata is IERC20 {
              /**
               * @dev Returns the name of the token.
               */
              function name() external view returns (string memory);
              /**
               * @dev Returns the symbol of the token.
               */
              function symbol() external view returns (string memory);
              /**
               * @dev Returns the decimals places of the token.
               */
              function decimals() external view returns (uint8);
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.9.4) (token/ERC20/extensions/IERC20Permit.sol)
          pragma solidity ^0.8.0;
          /**
           * @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
           * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
           *
           * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
           * presenting a message signed by the account. By not relying on {IERC20-approve}, the token holder account doesn't
           * need to send a transaction, and thus is not required to hold Ether at all.
           *
           * ==== Security Considerations
           *
           * There are two important considerations concerning the use of `permit`. The first is that a valid permit signature
           * expresses an allowance, and it should not be assumed to convey additional meaning. In particular, it should not be
           * considered as an intention to spend the allowance in any specific way. The second is that because permits have
           * built-in replay protection and can be submitted by anyone, they can be frontrun. A protocol that uses permits should
           * take this into consideration and allow a `permit` call to fail. Combining these two aspects, a pattern that may be
           * generally recommended is:
           *
           * ```solidity
           * function doThingWithPermit(..., uint256 value, uint256 deadline, uint8 v, bytes32 r, bytes32 s) public {
           *     try token.permit(msg.sender, address(this), value, deadline, v, r, s) {} catch {}
           *     doThing(..., value);
           * }
           *
           * function doThing(..., uint256 value) public {
           *     token.safeTransferFrom(msg.sender, address(this), value);
           *     ...
           * }
           * ```
           *
           * Observe that: 1) `msg.sender` is used as the owner, leaving no ambiguity as to the signer intent, and 2) the use of
           * `try/catch` allows the permit to fail and makes the code tolerant to frontrunning. (See also
           * {SafeERC20-safeTransferFrom}).
           *
           * Additionally, note that smart contract wallets (such as Argent or Safe) are not able to produce permit signatures, so
           * contracts should have entry points that don't rely on permit.
           */
          interface IERC20Permit {
              /**
               * @dev Sets `value` as the allowance of `spender` over ``owner``'s tokens,
               * given ``owner``'s signed approval.
               *
               * IMPORTANT: The same issues {IERC20-approve} has related to transaction
               * ordering also apply here.
               *
               * Emits an {Approval} event.
               *
               * Requirements:
               *
               * - `spender` cannot be the zero address.
               * - `deadline` must be a timestamp in the future.
               * - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner`
               * over the EIP712-formatted function arguments.
               * - the signature must use ``owner``'s current nonce (see {nonces}).
               *
               * For more information on the signature format, see the
               * https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP
               * section].
               *
               * CAUTION: See Security Considerations above.
               */
              function permit(
                  address owner,
                  address spender,
                  uint256 value,
                  uint256 deadline,
                  uint8 v,
                  bytes32 r,
                  bytes32 s
              ) external;
              /**
               * @dev Returns the current nonce for `owner`. This value must be
               * included whenever a signature is generated for {permit}.
               *
               * Every successful call to {permit} increases ``owner``'s nonce by one. This
               * prevents a signature from being used multiple times.
               */
              function nonces(address owner) external view returns (uint256);
              /**
               * @dev Returns the domain separator used in the encoding of the signature for {permit}, as defined by {EIP712}.
               */
              // solhint-disable-next-line func-name-mixedcase
              function DOMAIN_SEPARATOR() external view returns (bytes32);
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/IERC20.sol)
          pragma solidity ^0.8.0;
          /**
           * @dev Interface of the ERC20 standard as defined in the EIP.
           */
          interface IERC20 {
              /**
               * @dev Emitted when `value` tokens are moved from one account (`from`) to
               * another (`to`).
               *
               * Note that `value` may be zero.
               */
              event Transfer(address indexed from, address indexed to, uint256 value);
              /**
               * @dev Emitted when the allowance of a `spender` for an `owner` is set by
               * a call to {approve}. `value` is the new allowance.
               */
              event Approval(address indexed owner, address indexed spender, uint256 value);
              /**
               * @dev Returns the amount of tokens in existence.
               */
              function totalSupply() external view returns (uint256);
              /**
               * @dev Returns the amount of tokens owned by `account`.
               */
              function balanceOf(address account) external view returns (uint256);
              /**
               * @dev Moves `amount` tokens from the caller's account to `to`.
               *
               * Returns a boolean value indicating whether the operation succeeded.
               *
               * Emits a {Transfer} event.
               */
              function transfer(address to, uint256 amount) external returns (bool);
              /**
               * @dev Returns the remaining number of tokens that `spender` will be
               * allowed to spend on behalf of `owner` through {transferFrom}. This is
               * zero by default.
               *
               * This value changes when {approve} or {transferFrom} are called.
               */
              function allowance(address owner, address spender) external view returns (uint256);
              /**
               * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
               *
               * Returns a boolean value indicating whether the operation succeeded.
               *
               * IMPORTANT: Beware that changing an allowance with this method brings the risk
               * that someone may use both the old and the new allowance by unfortunate
               * transaction ordering. One possible solution to mitigate this race
               * condition is to first reduce the spender's allowance to 0 and set the
               * desired value afterwards:
               * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
               *
               * Emits an {Approval} event.
               */
              function approve(address spender, uint256 amount) external returns (bool);
              /**
               * @dev Moves `amount` tokens from `from` to `to` using the
               * allowance mechanism. `amount` is then deducted from the caller's
               * allowance.
               *
               * Returns a boolean value indicating whether the operation succeeded.
               *
               * Emits a {Transfer} event.
               */
              function transferFrom(address from, address to, uint256 amount) external returns (bool);
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.9.3) (token/ERC20/utils/SafeERC20.sol)
          pragma solidity ^0.8.0;
          import "../IERC20.sol";
          import "../extensions/IERC20Permit.sol";
          import "../../../utils/Address.sol";
          /**
           * @title SafeERC20
           * @dev Wrappers around ERC20 operations that throw on failure (when the token
           * contract returns false). Tokens that return no value (and instead revert or
           * throw on failure) are also supported, non-reverting calls are assumed to be
           * successful.
           * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
           * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
           */
          library SafeERC20 {
              using Address for address;
              /**
               * @dev Transfer `value` amount of `token` from the calling contract to `to`. If `token` returns no value,
               * non-reverting calls are assumed to be successful.
               */
              function safeTransfer(IERC20 token, address to, uint256 value) internal {
                  _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
              }
              /**
               * @dev Transfer `value` amount of `token` from `from` to `to`, spending the approval given by `from` to the
               * calling contract. If `token` returns no value, non-reverting calls are assumed to be successful.
               */
              function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
                  _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
              }
              /**
               * @dev Deprecated. This function has issues similar to the ones found in
               * {IERC20-approve}, and its usage is discouraged.
               *
               * Whenever possible, use {safeIncreaseAllowance} and
               * {safeDecreaseAllowance} instead.
               */
              function safeApprove(IERC20 token, address spender, uint256 value) internal {
                  // safeApprove should only be called when setting an initial allowance,
                  // or when resetting it to zero. To increase and decrease it, use
                  // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
                  require(
                      (value == 0) || (token.allowance(address(this), spender) == 0),
                      "SafeERC20: approve from non-zero to non-zero allowance"
                  );
                  _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
              }
              /**
               * @dev Increase the calling contract's allowance toward `spender` by `value`. If `token` returns no value,
               * non-reverting calls are assumed to be successful.
               */
              function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
                  uint256 oldAllowance = token.allowance(address(this), spender);
                  _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, oldAllowance + value));
              }
              /**
               * @dev Decrease the calling contract's allowance toward `spender` by `value`. If `token` returns no value,
               * non-reverting calls are assumed to be successful.
               */
              function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
                  unchecked {
                      uint256 oldAllowance = token.allowance(address(this), spender);
                      require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
                      _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, oldAllowance - value));
                  }
              }
              /**
               * @dev Set the calling contract's allowance toward `spender` to `value`. If `token` returns no value,
               * non-reverting calls are assumed to be successful. Meant to be used with tokens that require the approval
               * to be set to zero before setting it to a non-zero value, such as USDT.
               */
              function forceApprove(IERC20 token, address spender, uint256 value) internal {
                  bytes memory approvalCall = abi.encodeWithSelector(token.approve.selector, spender, value);
                  if (!_callOptionalReturnBool(token, approvalCall)) {
                      _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, 0));
                      _callOptionalReturn(token, approvalCall);
                  }
              }
              /**
               * @dev Use a ERC-2612 signature to set the `owner` approval toward `spender` on `token`.
               * Revert on invalid signature.
               */
              function safePermit(
                  IERC20Permit token,
                  address owner,
                  address spender,
                  uint256 value,
                  uint256 deadline,
                  uint8 v,
                  bytes32 r,
                  bytes32 s
              ) internal {
                  uint256 nonceBefore = token.nonces(owner);
                  token.permit(owner, spender, value, deadline, v, r, s);
                  uint256 nonceAfter = token.nonces(owner);
                  require(nonceAfter == nonceBefore + 1, "SafeERC20: permit did not succeed");
              }
              /**
               * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
               * on the return value: the return value is optional (but if data is returned, it must not be false).
               * @param token The token targeted by the call.
               * @param data The call data (encoded using abi.encode or one of its variants).
               */
              function _callOptionalReturn(IERC20 token, bytes memory data) private {
                  // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
                  // we're implementing it ourselves. We use {Address-functionCall} to perform this call, which verifies that
                  // the target address contains contract code and also asserts for success in the low-level call.
                  bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
                  require(returndata.length == 0 || abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
              }
              /**
               * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
               * on the return value: the return value is optional (but if data is returned, it must not be false).
               * @param token The token targeted by the call.
               * @param data The call data (encoded using abi.encode or one of its variants).
               *
               * This is a variant of {_callOptionalReturn} that silents catches all reverts and returns a bool instead.
               */
              function _callOptionalReturnBool(IERC20 token, bytes memory data) private returns (bool) {
                  // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
                  // we're implementing it ourselves. We cannot use {Address-functionCall} here since this should return false
                  // and not revert is the subcall reverts.
                  (bool success, bytes memory returndata) = address(token).call(data);
                  return
                      success && (returndata.length == 0 || abi.decode(returndata, (bool))) && Address.isContract(address(token));
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.9.0) (utils/Address.sol)
          pragma solidity ^0.8.1;
          /**
           * @dev Collection of functions related to the address type
           */
          library Address {
              /**
               * @dev Returns true if `account` is a contract.
               *
               * [IMPORTANT]
               * ====
               * It is unsafe to assume that an address for which this function returns
               * false is an externally-owned account (EOA) and not a contract.
               *
               * Among others, `isContract` will return false for the following
               * types of addresses:
               *
               *  - an externally-owned account
               *  - a contract in construction
               *  - an address where a contract will be created
               *  - an address where a contract lived, but was destroyed
               *
               * Furthermore, `isContract` will also return true if the target contract within
               * the same transaction is already scheduled for destruction by `SELFDESTRUCT`,
               * which only has an effect at the end of a transaction.
               * ====
               *
               * [IMPORTANT]
               * ====
               * You shouldn't rely on `isContract` to protect against flash loan attacks!
               *
               * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
               * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
               * constructor.
               * ====
               */
              function isContract(address account) internal view returns (bool) {
                  // This method relies on extcodesize/address.code.length, which returns 0
                  // for contracts in construction, since the code is only stored at the end
                  // of the constructor execution.
                  return account.code.length > 0;
              }
              /**
               * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
               * `recipient`, forwarding all available gas and reverting on errors.
               *
               * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
               * of certain opcodes, possibly making contracts go over the 2300 gas limit
               * imposed by `transfer`, making them unable to receive funds via
               * `transfer`. {sendValue} removes this limitation.
               *
               * https://consensys.net/diligence/blog/2019/09/stop-using-soliditys-transfer-now/[Learn more].
               *
               * IMPORTANT: because control is transferred to `recipient`, care must be
               * taken to not create reentrancy vulnerabilities. Consider using
               * {ReentrancyGuard} or the
               * https://solidity.readthedocs.io/en/v0.8.0/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
               */
              function sendValue(address payable recipient, uint256 amount) internal {
                  require(address(this).balance >= amount, "Address: insufficient balance");
                  (bool success, ) = recipient.call{value: amount}("");
                  require(success, "Address: unable to send value, recipient may have reverted");
              }
              /**
               * @dev Performs a Solidity function call using a low level `call`. A
               * plain `call` is an unsafe replacement for a function call: use this
               * function instead.
               *
               * If `target` reverts with a revert reason, it is bubbled up by this
               * function (like regular Solidity function calls).
               *
               * Returns the raw returned data. To convert to the expected return value,
               * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
               *
               * Requirements:
               *
               * - `target` must be a contract.
               * - calling `target` with `data` must not revert.
               *
               * _Available since v3.1._
               */
              function functionCall(address target, bytes memory data) internal returns (bytes memory) {
                  return functionCallWithValue(target, data, 0, "Address: low-level call failed");
              }
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
               * `errorMessage` as a fallback revert reason when `target` reverts.
               *
               * _Available since v3.1._
               */
              function functionCall(
                  address target,
                  bytes memory data,
                  string memory errorMessage
              ) internal returns (bytes memory) {
                  return functionCallWithValue(target, data, 0, errorMessage);
              }
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
               * but also transferring `value` wei to `target`.
               *
               * Requirements:
               *
               * - the calling contract must have an ETH balance of at least `value`.
               * - the called Solidity function must be `payable`.
               *
               * _Available since v3.1._
               */
              function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
                  return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
              }
              /**
               * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
               * with `errorMessage` as a fallback revert reason when `target` reverts.
               *
               * _Available since v3.1._
               */
              function functionCallWithValue(
                  address target,
                  bytes memory data,
                  uint256 value,
                  string memory errorMessage
              ) internal returns (bytes memory) {
                  require(address(this).balance >= value, "Address: insufficient balance for call");
                  (bool success, bytes memory returndata) = target.call{value: value}(data);
                  return verifyCallResultFromTarget(target, success, returndata, errorMessage);
              }
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
               * but performing a static call.
               *
               * _Available since v3.3._
               */
              function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
                  return functionStaticCall(target, data, "Address: low-level static call failed");
              }
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
               * but performing a static call.
               *
               * _Available since v3.3._
               */
              function functionStaticCall(
                  address target,
                  bytes memory data,
                  string memory errorMessage
              ) internal view returns (bytes memory) {
                  (bool success, bytes memory returndata) = target.staticcall(data);
                  return verifyCallResultFromTarget(target, success, returndata, errorMessage);
              }
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
               * but performing a delegate call.
               *
               * _Available since v3.4._
               */
              function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
                  return functionDelegateCall(target, data, "Address: low-level delegate call failed");
              }
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
               * but performing a delegate call.
               *
               * _Available since v3.4._
               */
              function functionDelegateCall(
                  address target,
                  bytes memory data,
                  string memory errorMessage
              ) internal returns (bytes memory) {
                  (bool success, bytes memory returndata) = target.delegatecall(data);
                  return verifyCallResultFromTarget(target, success, returndata, errorMessage);
              }
              /**
               * @dev Tool to verify that a low level call to smart-contract was successful, and revert (either by bubbling
               * the revert reason or using the provided one) in case of unsuccessful call or if target was not a contract.
               *
               * _Available since v4.8._
               */
              function verifyCallResultFromTarget(
                  address target,
                  bool success,
                  bytes memory returndata,
                  string memory errorMessage
              ) internal view returns (bytes memory) {
                  if (success) {
                      if (returndata.length == 0) {
                          // only check isContract if the call was successful and the return data is empty
                          // otherwise we already know that it was a contract
                          require(isContract(target), "Address: call to non-contract");
                      }
                      return returndata;
                  } else {
                      _revert(returndata, errorMessage);
                  }
              }
              /**
               * @dev Tool to verify that a low level call was successful, and revert if it wasn't, either by bubbling the
               * revert reason or using the provided one.
               *
               * _Available since v4.3._
               */
              function verifyCallResult(
                  bool success,
                  bytes memory returndata,
                  string memory errorMessage
              ) internal pure returns (bytes memory) {
                  if (success) {
                      return returndata;
                  } else {
                      _revert(returndata, errorMessage);
                  }
              }
              function _revert(bytes memory returndata, string memory errorMessage) private pure {
                  // Look for revert reason and bubble it up if present
                  if (returndata.length > 0) {
                      // The easiest way to bubble the revert reason is using memory via assembly
                      /// @solidity memory-safe-assembly
                      assembly {
                          let returndata_size := mload(returndata)
                          revert(add(32, returndata), returndata_size)
                      }
                  } else {
                      revert(errorMessage);
                  }
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.9.4) (utils/Context.sol)
          pragma solidity ^0.8.0;
          /**
           * @dev Provides information about the current execution context, including the
           * sender of the transaction and its data. While these are generally available
           * via msg.sender and msg.data, they should not be accessed in such a direct
           * manner, since when dealing with meta-transactions the account sending and
           * paying for execution may not be the actual sender (as far as an application
           * is concerned).
           *
           * This contract is only required for intermediate, library-like contracts.
           */
          abstract contract Context {
              function _msgSender() internal view virtual returns (address) {
                  return msg.sender;
              }
              function _msgData() internal view virtual returns (bytes calldata) {
                  return msg.data;
              }
              function _contextSuffixLength() internal view virtual returns (uint256) {
                  return 0;
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts v4.4.1 (utils/introspection/ERC165.sol)
          pragma solidity ^0.8.0;
          import "./IERC165.sol";
          /**
           * @dev Implementation of the {IERC165} interface.
           *
           * Contracts that want to implement ERC165 should inherit from this contract and override {supportsInterface} to check
           * for the additional interface id that will be supported. For example:
           *
           * ```solidity
           * function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
           *     return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId);
           * }
           * ```
           *
           * Alternatively, {ERC165Storage} provides an easier to use but more expensive implementation.
           */
          abstract contract ERC165 is IERC165 {
              /**
               * @dev See {IERC165-supportsInterface}.
               */
              function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
                  return interfaceId == type(IERC165).interfaceId;
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol)
          pragma solidity ^0.8.0;
          /**
           * @dev Interface of the ERC165 standard, as defined in the
           * https://eips.ethereum.org/EIPS/eip-165[EIP].
           *
           * Implementers can declare support of contract interfaces, which can then be
           * queried by others ({ERC165Checker}).
           *
           * For an implementation, see {ERC165}.
           */
          interface IERC165 {
              /**
               * @dev Returns true if this contract implements the interface defined by
               * `interfaceId`. See the corresponding
               * https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]
               * to learn more about how these ids are created.
               *
               * This function call must use less than 30 000 gas.
               */
              function supportsInterface(bytes4 interfaceId) external view returns (bool);
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.9.0) (utils/math/Math.sol)
          pragma solidity ^0.8.0;
          /**
           * @dev Standard math utilities missing in the Solidity language.
           */
          library Math {
              enum Rounding {
                  Down, // Toward negative infinity
                  Up, // Toward infinity
                  Zero // Toward zero
              }
              /**
               * @dev Returns the largest of two numbers.
               */
              function max(uint256 a, uint256 b) internal pure returns (uint256) {
                  return a > b ? a : b;
              }
              /**
               * @dev Returns the smallest of two numbers.
               */
              function min(uint256 a, uint256 b) internal pure returns (uint256) {
                  return a < b ? a : b;
              }
              /**
               * @dev Returns the average of two numbers. The result is rounded towards
               * zero.
               */
              function average(uint256 a, uint256 b) internal pure returns (uint256) {
                  // (a + b) / 2 can overflow.
                  return (a & b) + (a ^ b) / 2;
              }
              /**
               * @dev Returns the ceiling of the division of two numbers.
               *
               * This differs from standard division with `/` in that it rounds up instead
               * of rounding down.
               */
              function ceilDiv(uint256 a, uint256 b) internal pure returns (uint256) {
                  // (a + b - 1) / b can overflow on addition, so we distribute.
                  return a == 0 ? 0 : (a - 1) / b + 1;
              }
              /**
               * @notice Calculates floor(x * y / denominator) with full precision. Throws if result overflows a uint256 or denominator == 0
               * @dev Original credit to Remco Bloemen under MIT license (https://xn--2-umb.com/21/muldiv)
               * with further edits by Uniswap Labs also under MIT license.
               */
              function mulDiv(uint256 x, uint256 y, uint256 denominator) internal pure returns (uint256 result) {
                  unchecked {
                      // 512-bit multiply [prod1 prod0] = x * y. Compute the product mod 2^256 and mod 2^256 - 1, then use
                      // use the Chinese Remainder Theorem to reconstruct the 512 bit result. The result is stored in two 256
                      // variables such that product = prod1 * 2^256 + prod0.
                      uint256 prod0; // Least significant 256 bits of the product
                      uint256 prod1; // Most significant 256 bits of the product
                      assembly {
                          let mm := mulmod(x, y, not(0))
                          prod0 := mul(x, y)
                          prod1 := sub(sub(mm, prod0), lt(mm, prod0))
                      }
                      // Handle non-overflow cases, 256 by 256 division.
                      if (prod1 == 0) {
                          // Solidity will revert if denominator == 0, unlike the div opcode on its own.
                          // The surrounding unchecked block does not change this fact.
                          // See https://docs.soliditylang.org/en/latest/control-structures.html#checked-or-unchecked-arithmetic.
                          return prod0 / denominator;
                      }
                      // Make sure the result is less than 2^256. Also prevents denominator == 0.
                      require(denominator > prod1, "Math: mulDiv overflow");
                      ///////////////////////////////////////////////
                      // 512 by 256 division.
                      ///////////////////////////////////////////////
                      // Make division exact by subtracting the remainder from [prod1 prod0].
                      uint256 remainder;
                      assembly {
                          // Compute remainder using mulmod.
                          remainder := mulmod(x, y, denominator)
                          // Subtract 256 bit number from 512 bit number.
                          prod1 := sub(prod1, gt(remainder, prod0))
                          prod0 := sub(prod0, remainder)
                      }
                      // Factor powers of two out of denominator and compute largest power of two divisor of denominator. Always >= 1.
                      // See https://cs.stackexchange.com/q/138556/92363.
                      // Does not overflow because the denominator cannot be zero at this stage in the function.
                      uint256 twos = denominator & (~denominator + 1);
                      assembly {
                          // Divide denominator by twos.
                          denominator := div(denominator, twos)
                          // Divide [prod1 prod0] by twos.
                          prod0 := div(prod0, twos)
                          // Flip twos such that it is 2^256 / twos. If twos is zero, then it becomes one.
                          twos := add(div(sub(0, twos), twos), 1)
                      }
                      // Shift in bits from prod1 into prod0.
                      prod0 |= prod1 * twos;
                      // Invert denominator mod 2^256. Now that denominator is an odd number, it has an inverse modulo 2^256 such
                      // that denominator * inv = 1 mod 2^256. Compute the inverse by starting with a seed that is correct for
                      // four bits. That is, denominator * inv = 1 mod 2^4.
                      uint256 inverse = (3 * denominator) ^ 2;
                      // Use the Newton-Raphson iteration to improve the precision. Thanks to Hensel's lifting lemma, this also works
                      // in modular arithmetic, doubling the correct bits in each step.
                      inverse *= 2 - denominator * inverse; // inverse mod 2^8
                      inverse *= 2 - denominator * inverse; // inverse mod 2^16
                      inverse *= 2 - denominator * inverse; // inverse mod 2^32
                      inverse *= 2 - denominator * inverse; // inverse mod 2^64
                      inverse *= 2 - denominator * inverse; // inverse mod 2^128
                      inverse *= 2 - denominator * inverse; // inverse mod 2^256
                      // Because the division is now exact we can divide by multiplying with the modular inverse of denominator.
                      // This will give us the correct result modulo 2^256. Since the preconditions guarantee that the outcome is
                      // less than 2^256, this is the final result. We don't need to compute the high bits of the result and prod1
                      // is no longer required.
                      result = prod0 * inverse;
                      return result;
                  }
              }
              /**
               * @notice Calculates x * y / denominator with full precision, following the selected rounding direction.
               */
              function mulDiv(uint256 x, uint256 y, uint256 denominator, Rounding rounding) internal pure returns (uint256) {
                  uint256 result = mulDiv(x, y, denominator);
                  if (rounding == Rounding.Up && mulmod(x, y, denominator) > 0) {
                      result += 1;
                  }
                  return result;
              }
              /**
               * @dev Returns the square root of a number. If the number is not a perfect square, the value is rounded down.
               *
               * Inspired by Henry S. Warren, Jr.'s "Hacker's Delight" (Chapter 11).
               */
              function sqrt(uint256 a) internal pure returns (uint256) {
                  if (a == 0) {
                      return 0;
                  }
                  // For our first guess, we get the biggest power of 2 which is smaller than the square root of the target.
                  //
                  // We know that the "msb" (most significant bit) of our target number `a` is a power of 2 such that we have
                  // `msb(a) <= a < 2*msb(a)`. This value can be written `msb(a)=2**k` with `k=log2(a)`.
                  //
                  // This can be rewritten `2**log2(a) <= a < 2**(log2(a) + 1)`
                  // → `sqrt(2**k) <= sqrt(a) < sqrt(2**(k+1))`
                  // → `2**(k/2) <= sqrt(a) < 2**((k+1)/2) <= 2**(k/2 + 1)`
                  //
                  // Consequently, `2**(log2(a) / 2)` is a good first approximation of `sqrt(a)` with at least 1 correct bit.
                  uint256 result = 1 << (log2(a) >> 1);
                  // At this point `result` is an estimation with one bit of precision. We know the true value is a uint128,
                  // since it is the square root of a uint256. Newton's method converges quadratically (precision doubles at
                  // every iteration). We thus need at most 7 iteration to turn our partial result with one bit of precision
                  // into the expected uint128 result.
                  unchecked {
                      result = (result + a / result) >> 1;
                      result = (result + a / result) >> 1;
                      result = (result + a / result) >> 1;
                      result = (result + a / result) >> 1;
                      result = (result + a / result) >> 1;
                      result = (result + a / result) >> 1;
                      result = (result + a / result) >> 1;
                      return min(result, a / result);
                  }
              }
              /**
               * @notice Calculates sqrt(a), following the selected rounding direction.
               */
              function sqrt(uint256 a, Rounding rounding) internal pure returns (uint256) {
                  unchecked {
                      uint256 result = sqrt(a);
                      return result + (rounding == Rounding.Up && result * result < a ? 1 : 0);
                  }
              }
              /**
               * @dev Return the log in base 2, rounded down, of a positive value.
               * Returns 0 if given 0.
               */
              function log2(uint256 value) internal pure returns (uint256) {
                  uint256 result = 0;
                  unchecked {
                      if (value >> 128 > 0) {
                          value >>= 128;
                          result += 128;
                      }
                      if (value >> 64 > 0) {
                          value >>= 64;
                          result += 64;
                      }
                      if (value >> 32 > 0) {
                          value >>= 32;
                          result += 32;
                      }
                      if (value >> 16 > 0) {
                          value >>= 16;
                          result += 16;
                      }
                      if (value >> 8 > 0) {
                          value >>= 8;
                          result += 8;
                      }
                      if (value >> 4 > 0) {
                          value >>= 4;
                          result += 4;
                      }
                      if (value >> 2 > 0) {
                          value >>= 2;
                          result += 2;
                      }
                      if (value >> 1 > 0) {
                          result += 1;
                      }
                  }
                  return result;
              }
              /**
               * @dev Return the log in base 2, following the selected rounding direction, of a positive value.
               * Returns 0 if given 0.
               */
              function log2(uint256 value, Rounding rounding) internal pure returns (uint256) {
                  unchecked {
                      uint256 result = log2(value);
                      return result + (rounding == Rounding.Up && 1 << result < value ? 1 : 0);
                  }
              }
              /**
               * @dev Return the log in base 10, rounded down, of a positive value.
               * Returns 0 if given 0.
               */
              function log10(uint256 value) internal pure returns (uint256) {
                  uint256 result = 0;
                  unchecked {
                      if (value >= 10 ** 64) {
                          value /= 10 ** 64;
                          result += 64;
                      }
                      if (value >= 10 ** 32) {
                          value /= 10 ** 32;
                          result += 32;
                      }
                      if (value >= 10 ** 16) {
                          value /= 10 ** 16;
                          result += 16;
                      }
                      if (value >= 10 ** 8) {
                          value /= 10 ** 8;
                          result += 8;
                      }
                      if (value >= 10 ** 4) {
                          value /= 10 ** 4;
                          result += 4;
                      }
                      if (value >= 10 ** 2) {
                          value /= 10 ** 2;
                          result += 2;
                      }
                      if (value >= 10 ** 1) {
                          result += 1;
                      }
                  }
                  return result;
              }
              /**
               * @dev Return the log in base 10, following the selected rounding direction, of a positive value.
               * Returns 0 if given 0.
               */
              function log10(uint256 value, Rounding rounding) internal pure returns (uint256) {
                  unchecked {
                      uint256 result = log10(value);
                      return result + (rounding == Rounding.Up && 10 ** result < value ? 1 : 0);
                  }
              }
              /**
               * @dev Return the log in base 256, rounded down, of a positive value.
               * Returns 0 if given 0.
               *
               * Adding one to the result gives the number of pairs of hex symbols needed to represent `value` as a hex string.
               */
              function log256(uint256 value) internal pure returns (uint256) {
                  uint256 result = 0;
                  unchecked {
                      if (value >> 128 > 0) {
                          value >>= 128;
                          result += 16;
                      }
                      if (value >> 64 > 0) {
                          value >>= 64;
                          result += 8;
                      }
                      if (value >> 32 > 0) {
                          value >>= 32;
                          result += 4;
                      }
                      if (value >> 16 > 0) {
                          value >>= 16;
                          result += 2;
                      }
                      if (value >> 8 > 0) {
                          result += 1;
                      }
                  }
                  return result;
              }
              /**
               * @dev Return the log in base 256, following the selected rounding direction, of a positive value.
               * Returns 0 if given 0.
               */
              function log256(uint256 value, Rounding rounding) internal pure returns (uint256) {
                  unchecked {
                      uint256 result = log256(value);
                      return result + (rounding == Rounding.Up && 1 << (result << 3) < value ? 1 : 0);
                  }
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.8.0) (utils/math/SignedMath.sol)
          pragma solidity ^0.8.0;
          /**
           * @dev Standard signed math utilities missing in the Solidity language.
           */
          library SignedMath {
              /**
               * @dev Returns the largest of two signed numbers.
               */
              function max(int256 a, int256 b) internal pure returns (int256) {
                  return a > b ? a : b;
              }
              /**
               * @dev Returns the smallest of two signed numbers.
               */
              function min(int256 a, int256 b) internal pure returns (int256) {
                  return a < b ? a : b;
              }
              /**
               * @dev Returns the average of two signed numbers without overflow.
               * The result is rounded towards zero.
               */
              function average(int256 a, int256 b) internal pure returns (int256) {
                  // Formula from the book "Hacker's Delight"
                  int256 x = (a & b) + ((a ^ b) >> 1);
                  return x + (int256(uint256(x) >> 255) & (a ^ b));
              }
              /**
               * @dev Returns the absolute unsigned value of a signed value.
               */
              function abs(int256 n) internal pure returns (uint256) {
                  unchecked {
                      // must be unchecked in order to support `n = type(int256).min`
                      return uint256(n >= 0 ? n : -n);
                  }
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.9.0) (utils/Strings.sol)
          pragma solidity ^0.8.0;
          import "./math/Math.sol";
          import "./math/SignedMath.sol";
          /**
           * @dev String operations.
           */
          library Strings {
              bytes16 private constant _SYMBOLS = "0123456789abcdef";
              uint8 private constant _ADDRESS_LENGTH = 20;
              /**
               * @dev Converts a `uint256` to its ASCII `string` decimal representation.
               */
              function toString(uint256 value) internal pure returns (string memory) {
                  unchecked {
                      uint256 length = Math.log10(value) + 1;
                      string memory buffer = new string(length);
                      uint256 ptr;
                      /// @solidity memory-safe-assembly
                      assembly {
                          ptr := add(buffer, add(32, length))
                      }
                      while (true) {
                          ptr--;
                          /// @solidity memory-safe-assembly
                          assembly {
                              mstore8(ptr, byte(mod(value, 10), _SYMBOLS))
                          }
                          value /= 10;
                          if (value == 0) break;
                      }
                      return buffer;
                  }
              }
              /**
               * @dev Converts a `int256` to its ASCII `string` decimal representation.
               */
              function toString(int256 value) internal pure returns (string memory) {
                  return string(abi.encodePacked(value < 0 ? "-" : "", toString(SignedMath.abs(value))));
              }
              /**
               * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
               */
              function toHexString(uint256 value) internal pure returns (string memory) {
                  unchecked {
                      return toHexString(value, Math.log256(value) + 1);
                  }
              }
              /**
               * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.
               */
              function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {
                  bytes memory buffer = new bytes(2 * length + 2);
                  buffer[0] = "0";
                  buffer[1] = "x";
                  for (uint256 i = 2 * length + 1; i > 1; --i) {
                      buffer[i] = _SYMBOLS[value & 0xf];
                      value >>= 4;
                  }
                  require(value == 0, "Strings: hex length insufficient");
                  return string(buffer);
              }
              /**
               * @dev Converts an `address` with fixed length of 20 bytes to its not checksummed ASCII `string` hexadecimal representation.
               */
              function toHexString(address addr) internal pure returns (string memory) {
                  return toHexString(uint256(uint160(addr)), _ADDRESS_LENGTH);
              }
              /**
               * @dev Returns true if the two strings are equal.
               */
              function equal(string memory a, string memory b) internal pure returns (bool) {
                  return keccak256(bytes(a)) == keccak256(bytes(b));
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity 0.8.20;
          /*
           * @dev InvokeWayfinderHandler: Another type of contract in the Wayfinder ecosystem that will be deployed after Prompt.
           * @param _from - The address of the caller of invokeWayfinder
           * @param _nativeTokenDestination - The address to which native token was collected to before calling handleInvokeWayfinder
           * @param _promptDestination - The address to which PROMPT was collected to before calling handleInvokeWayfinder
           * @param _id - An id passed by the caller to represent any arbitrary and potentially off-chain event id
           * @param _nativeTokenValue - The amount of native token that was sent to the invokeWayfinder function (and was collected to _nativeTokenDestination)
           * @param _promptValue - The amount of PROMPT that was sent to the invokeWayfinder function (and was collected to _promptDestination)
           * @param _data - Catch-all param allowing callers to pass additional data
           */
          interface InvokeWayfinderHandler {
              function handleInvokeWayfinder(
                  address _from,
                  address _nativeTokenDestination,
                  address _promptDestination,
                  uint256 _id,
                  uint256 _nativeTokenValue,
                  uint256 _promptValue,
                  bytes memory _data
              ) external;
          }
          // SPDX-License-Identifier: MIT
          pragma solidity 0.8.20;
          interface IPromptToken {
              /**
               * @dev Fired when a new gateway (i.e. wayfinder handler contract) is registered
               * @param contractAddress - The address of the newly registered wayfinder handler contract
               * @param nativeTokenDestinationAddress - The address to which native token was collected
               * @param promptDestinationAddress - The address to which PRIME was collected
               */
              event WayfinderGatewayRegistered(
                  address indexed contractAddress,
                  address indexed nativeTokenDestinationAddress,
                  address indexed promptDestinationAddress
              );
              /**
               * @dev Fired when the handler is invoked
               * @param from - The address of the invoker
               * @param nativeTokenDestination - The address to which native token was collected
               * @param promptDestination - The address to which PRIME was collected
               * @param id - The arbitrary identifier used for tracking
               * @param nativeTokenValue - The amount of native token that was sent
               * @param promptValue - The amount of PRIME that was sent
               * @param data - Additional data that was sent
               */
              event WayfinderInvoked(
                  address indexed from,
                  address indexed nativeTokenDestination,
                  address indexed promptDestination,
                  uint256 id,
                  uint256 nativeTokenValue,
                  uint256 promptValue,
                  bytes data
              );
          }
          // SPDX-License-Identifier: MIT
          pragma solidity 0.8.20;
          import {ReentrancyGuard} from "@openzeppelin/contracts/security/ReentrancyGuard.sol";
          import {AccessControl} from "@openzeppelin/contracts/access/AccessControl.sol";
          import {OFT} from "@layerzerolabs/oft-evm/contracts/OFT.sol";
          import {ERC20Burnable} from "@openzeppelin/contracts/token/ERC20/extensions/ERC20Burnable.sol";
          import {IPromptToken} from "./interfaces/IPromptToken.sol";
          import {InvokeWayfinderHandler} from "./interfaces/InvokeWayfinderHandler.sol";
          contract PromptToken is
              IPromptToken,
              OFT,
              ReentrancyGuard,
              ERC20Burnable,
              AccessControl
          {
              /**
               * @notice ERC20 Name of the token: Prompt
               * @dev ERC20 function name() public view returns (string)
               * @dev Field is declared public: getter name() is created when compiled,
               *      it returns the name of the token.
               */
              string internal constant NAME = "Prompt";
              /**
               * @notice ERC20 Symbol of the token: PROMPT
               * @dev ERC20 function symbol() public view returns (string)
               * @dev Field is declared public: getter symbol() is created when compiled,
               *      it returns the symbol of the token
               */
              string internal constant SYMBOL = "PROMPT";
              /**
               * @notice Total supply of the token: 1,000,000,000
               * @dev ERC20 `function totalSupply() public view returns (uint256)`
               * @dev Field is declared public: getter totalSupply() is created when compiled,
               *      it returns the amount of tokens in existence.
               */
              uint256 internal constant SUPPLY = 1_000_000_000_000_000_000_000_000_000;
              /**
               * @dev Use INVOKE_WAYFINDER_CONFIGURATION_ROLE as DEFAULT_ADMIN_ROLE.
               *      Addresses with this role can set the invokeWayfinderHandlerContractAddress, set the
               *      invokeWayfinderDestination, and grant/revoke the INVOKE_WAYFINDER_CONFIGURATION_ROLE to other addresses
               */
              bytes32 public constant INVOKE_WAYFINDER_CONFIGURATION_ROLE =
                  DEFAULT_ADMIN_ROLE;
              /**
               * @notice WayfinderGateway record stores the details of an WayfinderGateways contract
               */
              struct WayfinderGateway {
                  address nativeTokenDestinationAddress;
                  address promptDestinationAddress;
                  InvokeWayfinderHandler invokeWayfinderHandler;
              }
              /**
               * @notice a record of all WayfinderGateways
               */
              mapping(address => WayfinderGateway) public wayfinderGateways;
              constructor(
                  address _lzEndpoint
              ) OFT(NAME, SYMBOL, _lzEndpoint, address(this)) {
                  _grantRole(INVOKE_WAYFINDER_CONFIGURATION_ROLE, msg.sender);
                  if (block.chainid == 1) {
                      _mint(msg.sender, SUPPLY);
                  }
              }
              /**
               * @notice Allow the caller to send PROMPT to the Wayfinder Ecosystem of smart
               *         contracts. PROMPT are collected to the destination address,
               *         handler is invoked to trigger downstream logic and events
               * @dev We do a transfer call as opposed to a transferFrom because normally when you call
               *      transferFrom from another contract, _msgSender() would be that contract itself, but since
               *      we are calling transferFrom from within the erc20 itself, the _msgSender() returns the caller
               *      From the following two lines, it will error out because 'from == wayfinderer'
               *      address wayfinderer = _msgSender();
               *      _wayfinderAllowance(from, wayfinderer, amount);
               *
               * @param _handlerAddress The address of the deployed and registered
               *        WayfinderGateways contract
               * @param _id An id passed by the caller to represent any arbitrary and
               *        potentially off-chain event id
               * @param _promptValue The amount of PROMPT that was sent to the
               *        invokeWayfinder function (and was collected to _destination)
               * @param _data Catch-all param to allow the caller to pass additional
               *        data to the handler
               */
              function invokeWayfinder(
                  address _handlerAddress,
                  uint256 _id,
                  uint256 _promptValue,
                  bytes memory _data
              ) public payable nonReentrant {
                  require(msg.value + _promptValue > 0, "No msg.value or PROMPT");
                  WayfinderGateway memory gateway = wayfinderGateways[_handlerAddress];
                  require(
                      gateway.promptDestinationAddress != address(0),
                      "not a handler"
                  );
                  if (msg.value > 0) {
                      (bool sent, ) = gateway.nativeTokenDestinationAddress.call{
                          value: msg.value
                      }("");
                      require(sent, "Failed to send native token");
                  }
                  // Transfer uses _msgSender() PROMPT from user, not from the OFT contract itself
                  if (_promptValue > 0) {
                      transfer(gateway.promptDestinationAddress, _promptValue);
                  }
                  // invoke the handler function with all transaction data
                  InvokeWayfinderHandler(_handlerAddress).handleInvokeWayfinder(
                      _msgSender(),
                      gateway.nativeTokenDestinationAddress,
                      gateway.promptDestinationAddress,
                      _id,
                      msg.value,
                      _promptValue,
                      _data
                  );
                  emit WayfinderInvoked(
                      _msgSender(),
                      gateway.nativeTokenDestinationAddress,
                      gateway.promptDestinationAddress,
                      _id,
                      msg.value,
                      _promptValue,
                      _data
                  );
              }
              /**
               * @notice Allow an address with ADMIN_ROLE to add a handler contract for invokeWayfinder
               * @dev additional handler contracts will be added to support new use cases, existing handler contracts can never be
               *      deleted nor replaced
               * @param _contractAddress - The address of the new invokeWayfinder handler contract to be registered
               * @param _nativeTokenDestinationAddress - The address to which MATIC is collected
               * @param _promptDestinationAddress - The address to which PROMPT is collected
               */
              function addWayfinderHandlerContract(
                  address _contractAddress,
                  address _nativeTokenDestinationAddress,
                  address _promptDestinationAddress
              ) public onlyRole(INVOKE_WAYFINDER_CONFIGURATION_ROLE) {
                  require(
                      _contractAddress != address(0) &&
                          _nativeTokenDestinationAddress != address(0) &&
                          _promptDestinationAddress != address(0),
                      "Destination addresses cannot be 0x0"
                  );
                  require(
                      address(
                          wayfinderGateways[_contractAddress].invokeWayfinderHandler
                      ) == address(0),
                      "Can't overwrite existing gateway"
                  );
                  wayfinderGateways[_contractAddress] = WayfinderGateway({
                      nativeTokenDestinationAddress: _nativeTokenDestinationAddress,
                      promptDestinationAddress: _promptDestinationAddress,
                      invokeWayfinderHandler: InvokeWayfinderHandler(_contractAddress)
                  });
                  emit WayfinderGatewayRegistered(
                      _contractAddress,
                      _nativeTokenDestinationAddress,
                      _promptDestinationAddress
                  );
              }
              /**
               * @dev Revokes `role` from the calling account.
               *
               * Preventing renouncing role.
               */
              function renounceRole(bytes32, address) public virtual override {
                  revert("Cannot renounce role");
              }
              /**
               * @dev Revokes `role` from `account`.
               *
               * If `account` had been granted `role`, emits a {RoleRevoked} event.
               *
               * Requirements:
               *
               * - the caller must have ``role``'s admin role.
               * - the caller must not be the account
               */
              function revokeRole(
                  bytes32 role,
                  address account
              ) public virtual override onlyRole(getRoleAdmin(role)) {
                  require(account != _msgSender(), "Cannot revoke role from self");
                  _revokeRole(role, account);
              }
              /**
               * @dev Leaves the contract without owner. It will not be possible to call
               * `onlyOwner` functions. Can only be called by the current owner.
               *
               * NOTE: Renouncing ownership will leave the contract without an owner,
               * thereby disabling any functionality that is only available to the owner.
               */
              function renounceOwnership() public virtual override onlyOwner {
                  revert("Cannot renounce role");
              }
          }
          

          File 4 of 4: FiatTokenV2_2
          /**
           * SPDX-License-Identifier: Apache-2.0
           *
           * Copyright (c) 2023, Circle Internet Financial, LLC.
           *
           * Licensed under the Apache License, Version 2.0 (the "License");
           * you may not use this file except in compliance with the License.
           * You may obtain a copy of the License at
           *
           * http://www.apache.org/licenses/LICENSE-2.0
           *
           * Unless required by applicable law or agreed to in writing, software
           * distributed under the License is distributed on an "AS IS" BASIS,
           * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
           * See the License for the specific language governing permissions and
           * limitations under the License.
           */
          pragma solidity 0.6.12;
          import { EIP712Domain } from "./EIP712Domain.sol"; // solhint-disable-line no-unused-import
          import { Blacklistable } from "../v1/Blacklistable.sol"; // solhint-disable-line no-unused-import
          import { FiatTokenV1 } from "../v1/FiatTokenV1.sol"; // solhint-disable-line no-unused-import
          import { FiatTokenV2 } from "./FiatTokenV2.sol"; // solhint-disable-line no-unused-import
          import { FiatTokenV2_1 } from "./FiatTokenV2_1.sol";
          import { EIP712 } from "../util/EIP712.sol";
          // solhint-disable func-name-mixedcase
          /**
           * @title FiatToken V2.2
           * @notice ERC20 Token backed by fiat reserves, version 2.2
           */
          contract FiatTokenV2_2 is FiatTokenV2_1 {
              /**
               * @notice Initialize v2.2
               * @param accountsToBlacklist   A list of accounts to migrate from the old blacklist
               * @param newSymbol             New token symbol
               * data structure to the new blacklist data structure.
               */
              function initializeV2_2(
                  address[] calldata accountsToBlacklist,
                  string calldata newSymbol
              ) external {
                  // solhint-disable-next-line reason-string
                  require(_initializedVersion == 2);
                  // Update fiat token symbol
                  symbol = newSymbol;
                  // Add previously blacklisted accounts to the new blacklist data structure
                  // and remove them from the old blacklist data structure.
                  for (uint256 i = 0; i < accountsToBlacklist.length; i++) {
                      require(
                          _deprecatedBlacklisted[accountsToBlacklist[i]],
                          "FiatTokenV2_2: Blacklisting previously unblacklisted account!"
                      );
                      _blacklist(accountsToBlacklist[i]);
                      delete _deprecatedBlacklisted[accountsToBlacklist[i]];
                  }
                  _blacklist(address(this));
                  delete _deprecatedBlacklisted[address(this)];
                  _initializedVersion = 3;
              }
              /**
               * @dev Internal function to get the current chain id.
               * @return The current chain id.
               */
              function _chainId() internal virtual view returns (uint256) {
                  uint256 chainId;
                  assembly {
                      chainId := chainid()
                  }
                  return chainId;
              }
              /**
               * @inheritdoc EIP712Domain
               */
              function _domainSeparator() internal override view returns (bytes32) {
                  return EIP712.makeDomainSeparator(name, "2", _chainId());
              }
              /**
               * @notice Update allowance with a signed permit
               * @dev EOA wallet signatures should be packed in the order of r, s, v.
               * @param owner       Token owner's address (Authorizer)
               * @param spender     Spender's address
               * @param value       Amount of allowance
               * @param deadline    The time at which the signature expires (unix time), or max uint256 value to signal no expiration
               * @param signature   Signature bytes signed by an EOA wallet or a contract wallet
               */
              function permit(
                  address owner,
                  address spender,
                  uint256 value,
                  uint256 deadline,
                  bytes memory signature
              ) external whenNotPaused {
                  _permit(owner, spender, value, deadline, signature);
              }
              /**
               * @notice Execute a transfer with a signed authorization
               * @dev EOA wallet signatures should be packed in the order of r, s, v.
               * @param from          Payer's address (Authorizer)
               * @param to            Payee's address
               * @param value         Amount to be transferred
               * @param validAfter    The time after which this is valid (unix time)
               * @param validBefore   The time before which this is valid (unix time)
               * @param nonce         Unique nonce
               * @param signature     Signature bytes signed by an EOA wallet or a contract wallet
               */
              function transferWithAuthorization(
                  address from,
                  address to,
                  uint256 value,
                  uint256 validAfter,
                  uint256 validBefore,
                  bytes32 nonce,
                  bytes memory signature
              ) external whenNotPaused notBlacklisted(from) notBlacklisted(to) {
                  _transferWithAuthorization(
                      from,
                      to,
                      value,
                      validAfter,
                      validBefore,
                      nonce,
                      signature
                  );
              }
              /**
               * @notice Receive a transfer with a signed authorization from the payer
               * @dev This has an additional check to ensure that the payee's address
               * matches the caller of this function to prevent front-running attacks.
               * EOA wallet signatures should be packed in the order of r, s, v.
               * @param from          Payer's address (Authorizer)
               * @param to            Payee's address
               * @param value         Amount to be transferred
               * @param validAfter    The time after which this is valid (unix time)
               * @param validBefore   The time before which this is valid (unix time)
               * @param nonce         Unique nonce
               * @param signature     Signature bytes signed by an EOA wallet or a contract wallet
               */
              function receiveWithAuthorization(
                  address from,
                  address to,
                  uint256 value,
                  uint256 validAfter,
                  uint256 validBefore,
                  bytes32 nonce,
                  bytes memory signature
              ) external whenNotPaused notBlacklisted(from) notBlacklisted(to) {
                  _receiveWithAuthorization(
                      from,
                      to,
                      value,
                      validAfter,
                      validBefore,
                      nonce,
                      signature
                  );
              }
              /**
               * @notice Attempt to cancel an authorization
               * @dev Works only if the authorization is not yet used.
               * EOA wallet signatures should be packed in the order of r, s, v.
               * @param authorizer    Authorizer's address
               * @param nonce         Nonce of the authorization
               * @param signature     Signature bytes signed by an EOA wallet or a contract wallet
               */
              function cancelAuthorization(
                  address authorizer,
                  bytes32 nonce,
                  bytes memory signature
              ) external whenNotPaused {
                  _cancelAuthorization(authorizer, nonce, signature);
              }
              /**
               * @dev Helper method that sets the blacklist state of an account on balanceAndBlacklistStates.
               * If _shouldBlacklist is true, we apply a (1 << 255) bitmask with an OR operation on the
               * account's balanceAndBlacklistState. This flips the high bit for the account to 1,
               * indicating that the account is blacklisted.
               *
               * If _shouldBlacklist if false, we reset the account's balanceAndBlacklistStates to their
               * balances. This clears the high bit for the account, indicating that the account is unblacklisted.
               * @param _account         The address of the account.
               * @param _shouldBlacklist True if the account should be blacklisted, false if the account should be unblacklisted.
               */
              function _setBlacklistState(address _account, bool _shouldBlacklist)
                  internal
                  override
              {
                  balanceAndBlacklistStates[_account] = _shouldBlacklist
                      ? balanceAndBlacklistStates[_account] | (1 << 255)
                      : _balanceOf(_account);
              }
              /**
               * @dev Helper method that sets the balance of an account on balanceAndBlacklistStates.
               * Since balances are stored in the last 255 bits of the balanceAndBlacklistStates value,
               * we need to ensure that the updated balance does not exceed (2^255 - 1).
               * Since blacklisted accounts' balances cannot be updated, the method will also
               * revert if the account is blacklisted
               * @param _account The address of the account.
               * @param _balance The new fiat token balance of the account (max: (2^255 - 1)).
               */
              function _setBalance(address _account, uint256 _balance) internal override {
                  require(
                      _balance <= ((1 << 255) - 1),
                      "FiatTokenV2_2: Balance exceeds (2^255 - 1)"
                  );
                  require(
                      !_isBlacklisted(_account),
                      "FiatTokenV2_2: Account is blacklisted"
                  );
                  balanceAndBlacklistStates[_account] = _balance;
              }
              /**
               * @inheritdoc Blacklistable
               */
              function _isBlacklisted(address _account)
                  internal
                  override
                  view
                  returns (bool)
              {
                  return balanceAndBlacklistStates[_account] >> 255 == 1;
              }
              /**
               * @dev Helper method to obtain the balance of an account. Since balances
               * are stored in the last 255 bits of the balanceAndBlacklistStates value,
               * we apply a ((1 << 255) - 1) bit bitmask with an AND operation on the
               * balanceAndBlacklistState to obtain the balance.
               * @param _account  The address of the account.
               * @return          The fiat token balance of the account.
               */
              function _balanceOf(address _account)
                  internal
                  override
                  view
                  returns (uint256)
              {
                  return balanceAndBlacklistStates[_account] & ((1 << 255) - 1);
              }
              /**
               * @inheritdoc FiatTokenV1
               */
              function approve(address spender, uint256 value)
                  external
                  override
                  whenNotPaused
                  returns (bool)
              {
                  _approve(msg.sender, spender, value);
                  return true;
              }
              /**
               * @inheritdoc FiatTokenV2
               */
              function permit(
                  address owner,
                  address spender,
                  uint256 value,
                  uint256 deadline,
                  uint8 v,
                  bytes32 r,
                  bytes32 s
              ) external override whenNotPaused {
                  _permit(owner, spender, value, deadline, v, r, s);
              }
              /**
               * @inheritdoc FiatTokenV2
               */
              function increaseAllowance(address spender, uint256 increment)
                  external
                  override
                  whenNotPaused
                  returns (bool)
              {
                  _increaseAllowance(msg.sender, spender, increment);
                  return true;
              }
              /**
               * @inheritdoc FiatTokenV2
               */
              function decreaseAllowance(address spender, uint256 decrement)
                  external
                  override
                  whenNotPaused
                  returns (bool)
              {
                  _decreaseAllowance(msg.sender, spender, decrement);
                  return true;
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.6.2 <0.8.0;
          /**
           * @dev Collection of functions related to the address type
           */
          library Address {
              /**
               * @dev Returns true if `account` is a contract.
               *
               * [IMPORTANT]
               * ====
               * It is unsafe to assume that an address for which this function returns
               * false is an externally-owned account (EOA) and not a contract.
               *
               * Among others, `isContract` will return false for the following
               * types of addresses:
               *
               *  - an externally-owned account
               *  - a contract in construction
               *  - an address where a contract will be created
               *  - an address where a contract lived, but was destroyed
               * ====
               */
              function isContract(address account) internal view returns (bool) {
                  // This method relies on extcodesize, which returns 0 for contracts in
                  // construction, since the code is only stored at the end of the
                  // constructor execution.
                  uint256 size;
                  // solhint-disable-next-line no-inline-assembly
                  assembly { size := extcodesize(account) }
                  return size > 0;
              }
              /**
               * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
               * `recipient`, forwarding all available gas and reverting on errors.
               *
               * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
               * of certain opcodes, possibly making contracts go over the 2300 gas limit
               * imposed by `transfer`, making them unable to receive funds via
               * `transfer`. {sendValue} removes this limitation.
               *
               * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
               *
               * IMPORTANT: because control is transferred to `recipient`, care must be
               * taken to not create reentrancy vulnerabilities. Consider using
               * {ReentrancyGuard} or the
               * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
               */
              function sendValue(address payable recipient, uint256 amount) internal {
                  require(address(this).balance >= amount, "Address: insufficient balance");
                  // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
                  (bool success, ) = recipient.call{ value: amount }("");
                  require(success, "Address: unable to send value, recipient may have reverted");
              }
              /**
               * @dev Performs a Solidity function call using a low level `call`. A
               * plain`call` is an unsafe replacement for a function call: use this
               * function instead.
               *
               * If `target` reverts with a revert reason, it is bubbled up by this
               * function (like regular Solidity function calls).
               *
               * Returns the raw returned data. To convert to the expected return value,
               * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
               *
               * Requirements:
               *
               * - `target` must be a contract.
               * - calling `target` with `data` must not revert.
               *
               * _Available since v3.1._
               */
              function functionCall(address target, bytes memory data) internal returns (bytes memory) {
                return functionCall(target, data, "Address: low-level call failed");
              }
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
               * `errorMessage` as a fallback revert reason when `target` reverts.
               *
               * _Available since v3.1._
               */
              function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
                  return functionCallWithValue(target, data, 0, errorMessage);
              }
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
               * but also transferring `value` wei to `target`.
               *
               * Requirements:
               *
               * - the calling contract must have an ETH balance of at least `value`.
               * - the called Solidity function must be `payable`.
               *
               * _Available since v3.1._
               */
              function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
                  return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
              }
              /**
               * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
               * with `errorMessage` as a fallback revert reason when `target` reverts.
               *
               * _Available since v3.1._
               */
              function functionCallWithValue(address target, bytes memory data, uint256 value, string memory errorMessage) internal returns (bytes memory) {
                  require(address(this).balance >= value, "Address: insufficient balance for call");
                  require(isContract(target), "Address: call to non-contract");
                  // solhint-disable-next-line avoid-low-level-calls
                  (bool success, bytes memory returndata) = target.call{ value: value }(data);
                  return _verifyCallResult(success, returndata, errorMessage);
              }
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
               * but performing a static call.
               *
               * _Available since v3.3._
               */
              function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
                  return functionStaticCall(target, data, "Address: low-level static call failed");
              }
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
               * but performing a static call.
               *
               * _Available since v3.3._
               */
              function functionStaticCall(address target, bytes memory data, string memory errorMessage) internal view returns (bytes memory) {
                  require(isContract(target), "Address: static call to non-contract");
                  // solhint-disable-next-line avoid-low-level-calls
                  (bool success, bytes memory returndata) = target.staticcall(data);
                  return _verifyCallResult(success, returndata, errorMessage);
              }
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
               * but performing a delegate call.
               *
               * _Available since v3.4._
               */
              function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
                  return functionDelegateCall(target, data, "Address: low-level delegate call failed");
              }
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
               * but performing a delegate call.
               *
               * _Available since v3.4._
               */
              function functionDelegateCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
                  require(isContract(target), "Address: delegate call to non-contract");
                  // solhint-disable-next-line avoid-low-level-calls
                  (bool success, bytes memory returndata) = target.delegatecall(data);
                  return _verifyCallResult(success, returndata, errorMessage);
              }
              function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private pure returns(bytes memory) {
                  if (success) {
                      return returndata;
                  } else {
                      // Look for revert reason and bubble it up if present
                      if (returndata.length > 0) {
                          // The easiest way to bubble the revert reason is using memory via assembly
                          // solhint-disable-next-line no-inline-assembly
                          assembly {
                              let returndata_size := mload(returndata)
                              revert(add(32, returndata), returndata_size)
                          }
                      } else {
                          revert(errorMessage);
                      }
                  }
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.6.0 <0.8.0;
          import "./IERC20.sol";
          import "../../math/SafeMath.sol";
          import "../../utils/Address.sol";
          /**
           * @title SafeERC20
           * @dev Wrappers around ERC20 operations that throw on failure (when the token
           * contract returns false). Tokens that return no value (and instead revert or
           * throw on failure) are also supported, non-reverting calls are assumed to be
           * successful.
           * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
           * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
           */
          library SafeERC20 {
              using SafeMath for uint256;
              using Address for address;
              function safeTransfer(IERC20 token, address to, uint256 value) internal {
                  _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
              }
              function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
                  _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
              }
              /**
               * @dev Deprecated. This function has issues similar to the ones found in
               * {IERC20-approve}, and its usage is discouraged.
               *
               * Whenever possible, use {safeIncreaseAllowance} and
               * {safeDecreaseAllowance} instead.
               */
              function safeApprove(IERC20 token, address spender, uint256 value) internal {
                  // safeApprove should only be called when setting an initial allowance,
                  // or when resetting it to zero. To increase and decrease it, use
                  // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
                  // solhint-disable-next-line max-line-length
                  require((value == 0) || (token.allowance(address(this), spender) == 0),
                      "SafeERC20: approve from non-zero to non-zero allowance"
                  );
                  _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
              }
              function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
                  uint256 newAllowance = token.allowance(address(this), spender).add(value);
                  _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
              }
              function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
                  uint256 newAllowance = token.allowance(address(this), spender).sub(value, "SafeERC20: decreased allowance below zero");
                  _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
              }
              /**
               * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
               * on the return value: the return value is optional (but if data is returned, it must not be false).
               * @param token The token targeted by the call.
               * @param data The call data (encoded using abi.encode or one of its variants).
               */
              function _callOptionalReturn(IERC20 token, bytes memory data) private {
                  // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
                  // we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that
                  // the target address contains contract code and also asserts for success in the low-level call.
                  bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
                  if (returndata.length > 0) { // Return data is optional
                      // solhint-disable-next-line max-line-length
                      require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
                  }
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.6.0 <0.8.0;
          /**
           * @dev Interface of the ERC20 standard as defined in the EIP.
           */
          interface IERC20 {
              /**
               * @dev Returns the amount of tokens in existence.
               */
              function totalSupply() external view returns (uint256);
              /**
               * @dev Returns the amount of tokens owned by `account`.
               */
              function balanceOf(address account) external view returns (uint256);
              /**
               * @dev Moves `amount` tokens from the caller's account to `recipient`.
               *
               * Returns a boolean value indicating whether the operation succeeded.
               *
               * Emits a {Transfer} event.
               */
              function transfer(address recipient, uint256 amount) external returns (bool);
              /**
               * @dev Returns the remaining number of tokens that `spender` will be
               * allowed to spend on behalf of `owner` through {transferFrom}. This is
               * zero by default.
               *
               * This value changes when {approve} or {transferFrom} are called.
               */
              function allowance(address owner, address spender) external view returns (uint256);
              /**
               * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
               *
               * Returns a boolean value indicating whether the operation succeeded.
               *
               * IMPORTANT: Beware that changing an allowance with this method brings the risk
               * that someone may use both the old and the new allowance by unfortunate
               * transaction ordering. One possible solution to mitigate this race
               * condition is to first reduce the spender's allowance to 0 and set the
               * desired value afterwards:
               * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
               *
               * Emits an {Approval} event.
               */
              function approve(address spender, uint256 amount) external returns (bool);
              /**
               * @dev Moves `amount` tokens from `sender` to `recipient` using the
               * allowance mechanism. `amount` is then deducted from the caller's
               * allowance.
               *
               * Returns a boolean value indicating whether the operation succeeded.
               *
               * Emits a {Transfer} event.
               */
              function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
              /**
               * @dev Emitted when `value` tokens are moved from one account (`from`) to
               * another (`to`).
               *
               * Note that `value` may be zero.
               */
              event Transfer(address indexed from, address indexed to, uint256 value);
              /**
               * @dev Emitted when the allowance of a `spender` for an `owner` is set by
               * a call to {approve}. `value` is the new allowance.
               */
              event Approval(address indexed owner, address indexed spender, uint256 value);
          }
          // SPDX-License-Identifier: MIT
          pragma solidity >=0.6.0 <0.8.0;
          /**
           * @dev Wrappers over Solidity's arithmetic operations with added overflow
           * checks.
           *
           * Arithmetic operations in Solidity wrap on overflow. This can easily result
           * in bugs, because programmers usually assume that an overflow raises an
           * error, which is the standard behavior in high level programming languages.
           * `SafeMath` restores this intuition by reverting the transaction when an
           * operation overflows.
           *
           * Using this library instead of the unchecked operations eliminates an entire
           * class of bugs, so it's recommended to use it always.
           */
          library SafeMath {
              /**
               * @dev Returns the addition of two unsigned integers, with an overflow flag.
               *
               * _Available since v3.4._
               */
              function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                  uint256 c = a + b;
                  if (c < a) return (false, 0);
                  return (true, c);
              }
              /**
               * @dev Returns the substraction of two unsigned integers, with an overflow flag.
               *
               * _Available since v3.4._
               */
              function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                  if (b > a) return (false, 0);
                  return (true, a - b);
              }
              /**
               * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
               *
               * _Available since v3.4._
               */
              function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                  // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
                  // benefit is lost if 'b' is also tested.
                  // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
                  if (a == 0) return (true, 0);
                  uint256 c = a * b;
                  if (c / a != b) return (false, 0);
                  return (true, c);
              }
              /**
               * @dev Returns the division of two unsigned integers, with a division by zero flag.
               *
               * _Available since v3.4._
               */
              function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                  if (b == 0) return (false, 0);
                  return (true, a / b);
              }
              /**
               * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
               *
               * _Available since v3.4._
               */
              function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                  if (b == 0) return (false, 0);
                  return (true, a % b);
              }
              /**
               * @dev Returns the addition of two unsigned integers, reverting on
               * overflow.
               *
               * Counterpart to Solidity's `+` operator.
               *
               * Requirements:
               *
               * - Addition cannot overflow.
               */
              function add(uint256 a, uint256 b) internal pure returns (uint256) {
                  uint256 c = a + b;
                  require(c >= a, "SafeMath: addition overflow");
                  return c;
              }
              /**
               * @dev Returns the subtraction of two unsigned integers, reverting on
               * overflow (when the result is negative).
               *
               * Counterpart to Solidity's `-` operator.
               *
               * Requirements:
               *
               * - Subtraction cannot overflow.
               */
              function sub(uint256 a, uint256 b) internal pure returns (uint256) {
                  require(b <= a, "SafeMath: subtraction overflow");
                  return a - b;
              }
              /**
               * @dev Returns the multiplication of two unsigned integers, reverting on
               * overflow.
               *
               * Counterpart to Solidity's `*` operator.
               *
               * Requirements:
               *
               * - Multiplication cannot overflow.
               */
              function mul(uint256 a, uint256 b) internal pure returns (uint256) {
                  if (a == 0) return 0;
                  uint256 c = a * b;
                  require(c / a == b, "SafeMath: multiplication overflow");
                  return c;
              }
              /**
               * @dev Returns the integer division of two unsigned integers, reverting on
               * division by zero. The result is rounded towards zero.
               *
               * Counterpart to Solidity's `/` operator. Note: this function uses a
               * `revert` opcode (which leaves remaining gas untouched) while Solidity
               * uses an invalid opcode to revert (consuming all remaining gas).
               *
               * Requirements:
               *
               * - The divisor cannot be zero.
               */
              function div(uint256 a, uint256 b) internal pure returns (uint256) {
                  require(b > 0, "SafeMath: division by zero");
                  return a / b;
              }
              /**
               * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
               * reverting when dividing by zero.
               *
               * Counterpart to Solidity's `%` operator. This function uses a `revert`
               * opcode (which leaves remaining gas untouched) while Solidity uses an
               * invalid opcode to revert (consuming all remaining gas).
               *
               * Requirements:
               *
               * - The divisor cannot be zero.
               */
              function mod(uint256 a, uint256 b) internal pure returns (uint256) {
                  require(b > 0, "SafeMath: modulo by zero");
                  return a % b;
              }
              /**
               * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
               * overflow (when the result is negative).
               *
               * CAUTION: This function is deprecated because it requires allocating memory for the error
               * message unnecessarily. For custom revert reasons use {trySub}.
               *
               * Counterpart to Solidity's `-` operator.
               *
               * Requirements:
               *
               * - Subtraction cannot overflow.
               */
              function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
                  require(b <= a, errorMessage);
                  return a - b;
              }
              /**
               * @dev Returns the integer division of two unsigned integers, reverting with custom message on
               * division by zero. The result is rounded towards zero.
               *
               * CAUTION: This function is deprecated because it requires allocating memory for the error
               * message unnecessarily. For custom revert reasons use {tryDiv}.
               *
               * Counterpart to Solidity's `/` operator. Note: this function uses a
               * `revert` opcode (which leaves remaining gas untouched) while Solidity
               * uses an invalid opcode to revert (consuming all remaining gas).
               *
               * Requirements:
               *
               * - The divisor cannot be zero.
               */
              function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
                  require(b > 0, errorMessage);
                  return a / b;
              }
              /**
               * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
               * reverting with custom message when dividing by zero.
               *
               * CAUTION: This function is deprecated because it requires allocating memory for the error
               * message unnecessarily. For custom revert reasons use {tryMod}.
               *
               * Counterpart to Solidity's `%` operator. This function uses a `revert`
               * opcode (which leaves remaining gas untouched) while Solidity uses an
               * invalid opcode to revert (consuming all remaining gas).
               *
               * Requirements:
               *
               * - The divisor cannot be zero.
               */
              function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
                  require(b > 0, errorMessage);
                  return a % b;
              }
          }
          /**
           * SPDX-License-Identifier: Apache-2.0
           *
           * Copyright (c) 2023, Circle Internet Financial, LLC.
           *
           * Licensed under the Apache License, Version 2.0 (the "License");
           * you may not use this file except in compliance with the License.
           * You may obtain a copy of the License at
           *
           * http://www.apache.org/licenses/LICENSE-2.0
           *
           * Unless required by applicable law or agreed to in writing, software
           * distributed under the License is distributed on an "AS IS" BASIS,
           * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
           * See the License for the specific language governing permissions and
           * limitations under the License.
           */
          pragma solidity 0.6.12;
          import { FiatTokenV2 } from "./FiatTokenV2.sol";
          // solhint-disable func-name-mixedcase
          /**
           * @title FiatToken V2.1
           * @notice ERC20 Token backed by fiat reserves, version 2.1
           */
          contract FiatTokenV2_1 is FiatTokenV2 {
              /**
               * @notice Initialize v2.1
               * @param lostAndFound  The address to which the locked funds are sent
               */
              function initializeV2_1(address lostAndFound) external {
                  // solhint-disable-next-line reason-string
                  require(_initializedVersion == 1);
                  uint256 lockedAmount = _balanceOf(address(this));
                  if (lockedAmount > 0) {
                      _transfer(address(this), lostAndFound, lockedAmount);
                  }
                  _blacklist(address(this));
                  _initializedVersion = 2;
              }
              /**
               * @notice Version string for the EIP712 domain separator
               * @return Version string
               */
              function version() external pure returns (string memory) {
                  return "2";
              }
          }
          /**
           * SPDX-License-Identifier: Apache-2.0
           *
           * Copyright (c) 2023, Circle Internet Financial, LLC.
           *
           * Licensed under the Apache License, Version 2.0 (the "License");
           * you may not use this file except in compliance with the License.
           * You may obtain a copy of the License at
           *
           * http://www.apache.org/licenses/LICENSE-2.0
           *
           * Unless required by applicable law or agreed to in writing, software
           * distributed under the License is distributed on an "AS IS" BASIS,
           * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
           * See the License for the specific language governing permissions and
           * limitations under the License.
           */
          pragma solidity 0.6.12;
          import { FiatTokenV1_1 } from "../v1.1/FiatTokenV1_1.sol";
          import { EIP712 } from "../util/EIP712.sol";
          import { EIP3009 } from "./EIP3009.sol";
          import { EIP2612 } from "./EIP2612.sol";
          /**
           * @title FiatToken V2
           * @notice ERC20 Token backed by fiat reserves, version 2
           */
          contract FiatTokenV2 is FiatTokenV1_1, EIP3009, EIP2612 {
              uint8 internal _initializedVersion;
              /**
               * @notice Initialize v2
               * @param newName   New token name
               */
              function initializeV2(string calldata newName) external {
                  // solhint-disable-next-line reason-string
                  require(initialized && _initializedVersion == 0);
                  name = newName;
                  _DEPRECATED_CACHED_DOMAIN_SEPARATOR = EIP712.makeDomainSeparator(
                      newName,
                      "2"
                  );
                  _initializedVersion = 1;
              }
              /**
               * @notice Increase the allowance by a given increment
               * @param spender   Spender's address
               * @param increment Amount of increase in allowance
               * @return True if successful
               */
              function increaseAllowance(address spender, uint256 increment)
                  external
                  virtual
                  whenNotPaused
                  notBlacklisted(msg.sender)
                  notBlacklisted(spender)
                  returns (bool)
              {
                  _increaseAllowance(msg.sender, spender, increment);
                  return true;
              }
              /**
               * @notice Decrease the allowance by a given decrement
               * @param spender   Spender's address
               * @param decrement Amount of decrease in allowance
               * @return True if successful
               */
              function decreaseAllowance(address spender, uint256 decrement)
                  external
                  virtual
                  whenNotPaused
                  notBlacklisted(msg.sender)
                  notBlacklisted(spender)
                  returns (bool)
              {
                  _decreaseAllowance(msg.sender, spender, decrement);
                  return true;
              }
              /**
               * @notice Execute a transfer with a signed authorization
               * @param from          Payer's address (Authorizer)
               * @param to            Payee's address
               * @param value         Amount to be transferred
               * @param validAfter    The time after which this is valid (unix time)
               * @param validBefore   The time before which this is valid (unix time)
               * @param nonce         Unique nonce
               * @param v             v of the signature
               * @param r             r of the signature
               * @param s             s of the signature
               */
              function transferWithAuthorization(
                  address from,
                  address to,
                  uint256 value,
                  uint256 validAfter,
                  uint256 validBefore,
                  bytes32 nonce,
                  uint8 v,
                  bytes32 r,
                  bytes32 s
              ) external whenNotPaused notBlacklisted(from) notBlacklisted(to) {
                  _transferWithAuthorization(
                      from,
                      to,
                      value,
                      validAfter,
                      validBefore,
                      nonce,
                      v,
                      r,
                      s
                  );
              }
              /**
               * @notice Receive a transfer with a signed authorization from the payer
               * @dev This has an additional check to ensure that the payee's address
               * matches the caller of this function to prevent front-running attacks.
               * @param from          Payer's address (Authorizer)
               * @param to            Payee's address
               * @param value         Amount to be transferred
               * @param validAfter    The time after which this is valid (unix time)
               * @param validBefore   The time before which this is valid (unix time)
               * @param nonce         Unique nonce
               * @param v             v of the signature
               * @param r             r of the signature
               * @param s             s of the signature
               */
              function receiveWithAuthorization(
                  address from,
                  address to,
                  uint256 value,
                  uint256 validAfter,
                  uint256 validBefore,
                  bytes32 nonce,
                  uint8 v,
                  bytes32 r,
                  bytes32 s
              ) external whenNotPaused notBlacklisted(from) notBlacklisted(to) {
                  _receiveWithAuthorization(
                      from,
                      to,
                      value,
                      validAfter,
                      validBefore,
                      nonce,
                      v,
                      r,
                      s
                  );
              }
              /**
               * @notice Attempt to cancel an authorization
               * @dev Works only if the authorization is not yet used.
               * @param authorizer    Authorizer's address
               * @param nonce         Nonce of the authorization
               * @param v             v of the signature
               * @param r             r of the signature
               * @param s             s of the signature
               */
              function cancelAuthorization(
                  address authorizer,
                  bytes32 nonce,
                  uint8 v,
                  bytes32 r,
                  bytes32 s
              ) external whenNotPaused {
                  _cancelAuthorization(authorizer, nonce, v, r, s);
              }
              /**
               * @notice Update allowance with a signed permit
               * @param owner       Token owner's address (Authorizer)
               * @param spender     Spender's address
               * @param value       Amount of allowance
               * @param deadline    The time at which the signature expires (unix time), or max uint256 value to signal no expiration
               * @param v           v of the signature
               * @param r           r of the signature
               * @param s           s of the signature
               */
              function permit(
                  address owner,
                  address spender,
                  uint256 value,
                  uint256 deadline,
                  uint8 v,
                  bytes32 r,
                  bytes32 s
              )
                  external
                  virtual
                  whenNotPaused
                  notBlacklisted(owner)
                  notBlacklisted(spender)
              {
                  _permit(owner, spender, value, deadline, v, r, s);
              }
              /**
               * @dev Internal function to increase the allowance by a given increment
               * @param owner     Token owner's address
               * @param spender   Spender's address
               * @param increment Amount of increase
               */
              function _increaseAllowance(
                  address owner,
                  address spender,
                  uint256 increment
              ) internal override {
                  _approve(owner, spender, allowed[owner][spender].add(increment));
              }
              /**
               * @dev Internal function to decrease the allowance by a given decrement
               * @param owner     Token owner's address
               * @param spender   Spender's address
               * @param decrement Amount of decrease
               */
              function _decreaseAllowance(
                  address owner,
                  address spender,
                  uint256 decrement
              ) internal override {
                  _approve(
                      owner,
                      spender,
                      allowed[owner][spender].sub(
                          decrement,
                          "ERC20: decreased allowance below zero"
                      )
                  );
              }
          }
          /**
           * SPDX-License-Identifier: Apache-2.0
           *
           * Copyright (c) 2023, Circle Internet Financial, LLC.
           *
           * Licensed under the Apache License, Version 2.0 (the "License");
           * you may not use this file except in compliance with the License.
           * You may obtain a copy of the License at
           *
           * http://www.apache.org/licenses/LICENSE-2.0
           *
           * Unless required by applicable law or agreed to in writing, software
           * distributed under the License is distributed on an "AS IS" BASIS,
           * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
           * See the License for the specific language governing permissions and
           * limitations under the License.
           */
          pragma solidity 0.6.12;
          // solhint-disable func-name-mixedcase
          /**
           * @title EIP712 Domain
           */
          contract EIP712Domain {
              // was originally DOMAIN_SEPARATOR
              // but that has been moved to a method so we can override it in V2_2+
              bytes32 internal _DEPRECATED_CACHED_DOMAIN_SEPARATOR;
              /**
               * @notice Get the EIP712 Domain Separator.
               * @return The bytes32 EIP712 domain separator.
               */
              function DOMAIN_SEPARATOR() external view returns (bytes32) {
                  return _domainSeparator();
              }
              /**
               * @dev Internal method to get the EIP712 Domain Separator.
               * @return The bytes32 EIP712 domain separator.
               */
              function _domainSeparator() internal virtual view returns (bytes32) {
                  return _DEPRECATED_CACHED_DOMAIN_SEPARATOR;
              }
          }
          /**
           * SPDX-License-Identifier: Apache-2.0
           *
           * Copyright (c) 2023, Circle Internet Financial, LLC.
           *
           * Licensed under the Apache License, Version 2.0 (the "License");
           * you may not use this file except in compliance with the License.
           * You may obtain a copy of the License at
           *
           * http://www.apache.org/licenses/LICENSE-2.0
           *
           * Unless required by applicable law or agreed to in writing, software
           * distributed under the License is distributed on an "AS IS" BASIS,
           * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
           * See the License for the specific language governing permissions and
           * limitations under the License.
           */
          pragma solidity 0.6.12;
          import { AbstractFiatTokenV2 } from "./AbstractFiatTokenV2.sol";
          import { EIP712Domain } from "./EIP712Domain.sol";
          import { SignatureChecker } from "../util/SignatureChecker.sol";
          import { MessageHashUtils } from "../util/MessageHashUtils.sol";
          /**
           * @title EIP-3009
           * @notice Provide internal implementation for gas-abstracted transfers
           * @dev Contracts that inherit from this must wrap these with publicly
           * accessible functions, optionally adding modifiers where necessary
           */
          abstract contract EIP3009 is AbstractFiatTokenV2, EIP712Domain {
              // keccak256("TransferWithAuthorization(address from,address to,uint256 value,uint256 validAfter,uint256 validBefore,bytes32 nonce)")
              bytes32
                  public constant TRANSFER_WITH_AUTHORIZATION_TYPEHASH = 0x7c7c6cdb67a18743f49ec6fa9b35f50d52ed05cbed4cc592e13b44501c1a2267;
              // keccak256("ReceiveWithAuthorization(address from,address to,uint256 value,uint256 validAfter,uint256 validBefore,bytes32 nonce)")
              bytes32
                  public constant RECEIVE_WITH_AUTHORIZATION_TYPEHASH = 0xd099cc98ef71107a616c4f0f941f04c322d8e254fe26b3c6668db87aae413de8;
              // keccak256("CancelAuthorization(address authorizer,bytes32 nonce)")
              bytes32
                  public constant CANCEL_AUTHORIZATION_TYPEHASH = 0x158b0a9edf7a828aad02f63cd515c68ef2f50ba807396f6d12842833a1597429;
              /**
               * @dev authorizer address => nonce => bool (true if nonce is used)
               */
              mapping(address => mapping(bytes32 => bool)) private _authorizationStates;
              event AuthorizationUsed(address indexed authorizer, bytes32 indexed nonce);
              event AuthorizationCanceled(
                  address indexed authorizer,
                  bytes32 indexed nonce
              );
              /**
               * @notice Returns the state of an authorization
               * @dev Nonces are randomly generated 32-byte data unique to the
               * authorizer's address
               * @param authorizer    Authorizer's address
               * @param nonce         Nonce of the authorization
               * @return True if the nonce is used
               */
              function authorizationState(address authorizer, bytes32 nonce)
                  external
                  view
                  returns (bool)
              {
                  return _authorizationStates[authorizer][nonce];
              }
              /**
               * @notice Execute a transfer with a signed authorization
               * @param from          Payer's address (Authorizer)
               * @param to            Payee's address
               * @param value         Amount to be transferred
               * @param validAfter    The time after which this is valid (unix time)
               * @param validBefore   The time before which this is valid (unix time)
               * @param nonce         Unique nonce
               * @param v             v of the signature
               * @param r             r of the signature
               * @param s             s of the signature
               */
              function _transferWithAuthorization(
                  address from,
                  address to,
                  uint256 value,
                  uint256 validAfter,
                  uint256 validBefore,
                  bytes32 nonce,
                  uint8 v,
                  bytes32 r,
                  bytes32 s
              ) internal {
                  _transferWithAuthorization(
                      from,
                      to,
                      value,
                      validAfter,
                      validBefore,
                      nonce,
                      abi.encodePacked(r, s, v)
                  );
              }
              /**
               * @notice Execute a transfer with a signed authorization
               * @dev EOA wallet signatures should be packed in the order of r, s, v.
               * @param from          Payer's address (Authorizer)
               * @param to            Payee's address
               * @param value         Amount to be transferred
               * @param validAfter    The time after which this is valid (unix time)
               * @param validBefore   The time before which this is valid (unix time)
               * @param nonce         Unique nonce
               * @param signature     Signature byte array produced by an EOA wallet or a contract wallet
               */
              function _transferWithAuthorization(
                  address from,
                  address to,
                  uint256 value,
                  uint256 validAfter,
                  uint256 validBefore,
                  bytes32 nonce,
                  bytes memory signature
              ) internal {
                  _requireValidAuthorization(from, nonce, validAfter, validBefore);
                  _requireValidSignature(
                      from,
                      keccak256(
                          abi.encode(
                              TRANSFER_WITH_AUTHORIZATION_TYPEHASH,
                              from,
                              to,
                              value,
                              validAfter,
                              validBefore,
                              nonce
                          )
                      ),
                      signature
                  );
                  _markAuthorizationAsUsed(from, nonce);
                  _transfer(from, to, value);
              }
              /**
               * @notice Receive a transfer with a signed authorization from the payer
               * @dev This has an additional check to ensure that the payee's address
               * matches the caller of this function to prevent front-running attacks.
               * @param from          Payer's address (Authorizer)
               * @param to            Payee's address
               * @param value         Amount to be transferred
               * @param validAfter    The time after which this is valid (unix time)
               * @param validBefore   The time before which this is valid (unix time)
               * @param nonce         Unique nonce
               * @param v             v of the signature
               * @param r             r of the signature
               * @param s             s of the signature
               */
              function _receiveWithAuthorization(
                  address from,
                  address to,
                  uint256 value,
                  uint256 validAfter,
                  uint256 validBefore,
                  bytes32 nonce,
                  uint8 v,
                  bytes32 r,
                  bytes32 s
              ) internal {
                  _receiveWithAuthorization(
                      from,
                      to,
                      value,
                      validAfter,
                      validBefore,
                      nonce,
                      abi.encodePacked(r, s, v)
                  );
              }
              /**
               * @notice Receive a transfer with a signed authorization from the payer
               * @dev This has an additional check to ensure that the payee's address
               * matches the caller of this function to prevent front-running attacks.
               * EOA wallet signatures should be packed in the order of r, s, v.
               * @param from          Payer's address (Authorizer)
               * @param to            Payee's address
               * @param value         Amount to be transferred
               * @param validAfter    The time after which this is valid (unix time)
               * @param validBefore   The time before which this is valid (unix time)
               * @param nonce         Unique nonce
               * @param signature     Signature byte array produced by an EOA wallet or a contract wallet
               */
              function _receiveWithAuthorization(
                  address from,
                  address to,
                  uint256 value,
                  uint256 validAfter,
                  uint256 validBefore,
                  bytes32 nonce,
                  bytes memory signature
              ) internal {
                  require(to == msg.sender, "FiatTokenV2: caller must be the payee");
                  _requireValidAuthorization(from, nonce, validAfter, validBefore);
                  _requireValidSignature(
                      from,
                      keccak256(
                          abi.encode(
                              RECEIVE_WITH_AUTHORIZATION_TYPEHASH,
                              from,
                              to,
                              value,
                              validAfter,
                              validBefore,
                              nonce
                          )
                      ),
                      signature
                  );
                  _markAuthorizationAsUsed(from, nonce);
                  _transfer(from, to, value);
              }
              /**
               * @notice Attempt to cancel an authorization
               * @param authorizer    Authorizer's address
               * @param nonce         Nonce of the authorization
               * @param v             v of the signature
               * @param r             r of the signature
               * @param s             s of the signature
               */
              function _cancelAuthorization(
                  address authorizer,
                  bytes32 nonce,
                  uint8 v,
                  bytes32 r,
                  bytes32 s
              ) internal {
                  _cancelAuthorization(authorizer, nonce, abi.encodePacked(r, s, v));
              }
              /**
               * @notice Attempt to cancel an authorization
               * @dev EOA wallet signatures should be packed in the order of r, s, v.
               * @param authorizer    Authorizer's address
               * @param nonce         Nonce of the authorization
               * @param signature     Signature byte array produced by an EOA wallet or a contract wallet
               */
              function _cancelAuthorization(
                  address authorizer,
                  bytes32 nonce,
                  bytes memory signature
              ) internal {
                  _requireUnusedAuthorization(authorizer, nonce);
                  _requireValidSignature(
                      authorizer,
                      keccak256(
                          abi.encode(CANCEL_AUTHORIZATION_TYPEHASH, authorizer, nonce)
                      ),
                      signature
                  );
                  _authorizationStates[authorizer][nonce] = true;
                  emit AuthorizationCanceled(authorizer, nonce);
              }
              /**
               * @notice Validates that signature against input data struct
               * @param signer        Signer's address
               * @param dataHash      Hash of encoded data struct
               * @param signature     Signature byte array produced by an EOA wallet or a contract wallet
               */
              function _requireValidSignature(
                  address signer,
                  bytes32 dataHash,
                  bytes memory signature
              ) private view {
                  require(
                      SignatureChecker.isValidSignatureNow(
                          signer,
                          MessageHashUtils.toTypedDataHash(_domainSeparator(), dataHash),
                          signature
                      ),
                      "FiatTokenV2: invalid signature"
                  );
              }
              /**
               * @notice Check that an authorization is unused
               * @param authorizer    Authorizer's address
               * @param nonce         Nonce of the authorization
               */
              function _requireUnusedAuthorization(address authorizer, bytes32 nonce)
                  private
                  view
              {
                  require(
                      !_authorizationStates[authorizer][nonce],
                      "FiatTokenV2: authorization is used or canceled"
                  );
              }
              /**
               * @notice Check that authorization is valid
               * @param authorizer    Authorizer's address
               * @param nonce         Nonce of the authorization
               * @param validAfter    The time after which this is valid (unix time)
               * @param validBefore   The time before which this is valid (unix time)
               */
              function _requireValidAuthorization(
                  address authorizer,
                  bytes32 nonce,
                  uint256 validAfter,
                  uint256 validBefore
              ) private view {
                  require(
                      now > validAfter,
                      "FiatTokenV2: authorization is not yet valid"
                  );
                  require(now < validBefore, "FiatTokenV2: authorization is expired");
                  _requireUnusedAuthorization(authorizer, nonce);
              }
              /**
               * @notice Mark an authorization as used
               * @param authorizer    Authorizer's address
               * @param nonce         Nonce of the authorization
               */
              function _markAuthorizationAsUsed(address authorizer, bytes32 nonce)
                  private
              {
                  _authorizationStates[authorizer][nonce] = true;
                  emit AuthorizationUsed(authorizer, nonce);
              }
          }
          /**
           * SPDX-License-Identifier: Apache-2.0
           *
           * Copyright (c) 2023, Circle Internet Financial, LLC.
           *
           * Licensed under the Apache License, Version 2.0 (the "License");
           * you may not use this file except in compliance with the License.
           * You may obtain a copy of the License at
           *
           * http://www.apache.org/licenses/LICENSE-2.0
           *
           * Unless required by applicable law or agreed to in writing, software
           * distributed under the License is distributed on an "AS IS" BASIS,
           * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
           * See the License for the specific language governing permissions and
           * limitations under the License.
           */
          pragma solidity 0.6.12;
          import { AbstractFiatTokenV2 } from "./AbstractFiatTokenV2.sol";
          import { EIP712Domain } from "./EIP712Domain.sol";
          import { MessageHashUtils } from "../util/MessageHashUtils.sol";
          import { SignatureChecker } from "../util/SignatureChecker.sol";
          /**
           * @title EIP-2612
           * @notice Provide internal implementation for gas-abstracted approvals
           */
          abstract contract EIP2612 is AbstractFiatTokenV2, EIP712Domain {
              // keccak256("Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)")
              bytes32
                  public constant PERMIT_TYPEHASH = 0x6e71edae12b1b97f4d1f60370fef10105fa2faae0126114a169c64845d6126c9;
              mapping(address => uint256) private _permitNonces;
              /**
               * @notice Nonces for permit
               * @param owner Token owner's address (Authorizer)
               * @return Next nonce
               */
              function nonces(address owner) external view returns (uint256) {
                  return _permitNonces[owner];
              }
              /**
               * @notice Verify a signed approval permit and execute if valid
               * @param owner     Token owner's address (Authorizer)
               * @param spender   Spender's address
               * @param value     Amount of allowance
               * @param deadline  The time at which the signature expires (unix time), or max uint256 value to signal no expiration
               * @param v         v of the signature
               * @param r         r of the signature
               * @param s         s of the signature
               */
              function _permit(
                  address owner,
                  address spender,
                  uint256 value,
                  uint256 deadline,
                  uint8 v,
                  bytes32 r,
                  bytes32 s
              ) internal {
                  _permit(owner, spender, value, deadline, abi.encodePacked(r, s, v));
              }
              /**
               * @notice Verify a signed approval permit and execute if valid
               * @dev EOA wallet signatures should be packed in the order of r, s, v.
               * @param owner      Token owner's address (Authorizer)
               * @param spender    Spender's address
               * @param value      Amount of allowance
               * @param deadline   The time at which the signature expires (unix time), or max uint256 value to signal no expiration
               * @param signature  Signature byte array signed by an EOA wallet or a contract wallet
               */
              function _permit(
                  address owner,
                  address spender,
                  uint256 value,
                  uint256 deadline,
                  bytes memory signature
              ) internal {
                  require(
                      deadline == type(uint256).max || deadline >= now,
                      "FiatTokenV2: permit is expired"
                  );
                  bytes32 typedDataHash = MessageHashUtils.toTypedDataHash(
                      _domainSeparator(),
                      keccak256(
                          abi.encode(
                              PERMIT_TYPEHASH,
                              owner,
                              spender,
                              value,
                              _permitNonces[owner]++,
                              deadline
                          )
                      )
                  );
                  require(
                      SignatureChecker.isValidSignatureNow(
                          owner,
                          typedDataHash,
                          signature
                      ),
                      "EIP2612: invalid signature"
                  );
                  _approve(owner, spender, value);
              }
          }
          /**
           * SPDX-License-Identifier: Apache-2.0
           *
           * Copyright (c) 2023, Circle Internet Financial, LLC.
           *
           * Licensed under the Apache License, Version 2.0 (the "License");
           * you may not use this file except in compliance with the License.
           * You may obtain a copy of the License at
           *
           * http://www.apache.org/licenses/LICENSE-2.0
           *
           * Unless required by applicable law or agreed to in writing, software
           * distributed under the License is distributed on an "AS IS" BASIS,
           * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
           * See the License for the specific language governing permissions and
           * limitations under the License.
           */
          pragma solidity 0.6.12;
          import { AbstractFiatTokenV1 } from "../v1/AbstractFiatTokenV1.sol";
          abstract contract AbstractFiatTokenV2 is AbstractFiatTokenV1 {
              function _increaseAllowance(
                  address owner,
                  address spender,
                  uint256 increment
              ) internal virtual;
              function _decreaseAllowance(
                  address owner,
                  address spender,
                  uint256 decrement
              ) internal virtual;
          }
          /**
           * SPDX-License-Identifier: MIT
           *
           * Copyright (c) 2016 Smart Contract Solutions, Inc.
           * Copyright (c) 2018-2020 CENTRE SECZ
           *
           * Permission is hereby granted, free of charge, to any person obtaining a copy
           * of this software and associated documentation files (the "Software"), to deal
           * in the Software without restriction, including without limitation the rights
           * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
           * copies of the Software, and to permit persons to whom the Software is
           * furnished to do so, subject to the following conditions:
           *
           * The above copyright notice and this permission notice shall be included in
           * copies or substantial portions of the Software.
           *
           * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
           * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
           * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
           * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
           * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
           * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
           * SOFTWARE.
           */
          pragma solidity 0.6.12;
          import { Ownable } from "./Ownable.sol";
          /**
           * @notice Base contract which allows children to implement an emergency stop
           * mechanism
           * @dev Forked from https://github.com/OpenZeppelin/openzeppelin-contracts/blob/feb665136c0dae9912e08397c1a21c4af3651ef3/contracts/lifecycle/Pausable.sol
           * Modifications:
           * 1. Added pauser role, switched pause/unpause to be onlyPauser (6/14/2018)
           * 2. Removed whenNotPause/whenPaused from pause/unpause (6/14/2018)
           * 3. Removed whenPaused (6/14/2018)
           * 4. Switches ownable library to use ZeppelinOS (7/12/18)
           * 5. Remove constructor (7/13/18)
           * 6. Reformat, conform to Solidity 0.6 syntax and add error messages (5/13/20)
           * 7. Make public functions external (5/27/20)
           */
          contract Pausable is Ownable {
              event Pause();
              event Unpause();
              event PauserChanged(address indexed newAddress);
              address public pauser;
              bool public paused = false;
              /**
               * @dev Modifier to make a function callable only when the contract is not paused.
               */
              modifier whenNotPaused() {
                  require(!paused, "Pausable: paused");
                  _;
              }
              /**
               * @dev throws if called by any account other than the pauser
               */
              modifier onlyPauser() {
                  require(msg.sender == pauser, "Pausable: caller is not the pauser");
                  _;
              }
              /**
               * @dev called by the owner to pause, triggers stopped state
               */
              function pause() external onlyPauser {
                  paused = true;
                  emit Pause();
              }
              /**
               * @dev called by the owner to unpause, returns to normal state
               */
              function unpause() external onlyPauser {
                  paused = false;
                  emit Unpause();
              }
              /**
               * @notice Updates the pauser address.
               * @param _newPauser The address of the new pauser.
               */
              function updatePauser(address _newPauser) external onlyOwner {
                  require(
                      _newPauser != address(0),
                      "Pausable: new pauser is the zero address"
                  );
                  pauser = _newPauser;
                  emit PauserChanged(pauser);
              }
          }
          /**
           * SPDX-License-Identifier: MIT
           *
           * Copyright (c) 2018 zOS Global Limited.
           * Copyright (c) 2018-2020 CENTRE SECZ
           *
           * Permission is hereby granted, free of charge, to any person obtaining a copy
           * of this software and associated documentation files (the "Software"), to deal
           * in the Software without restriction, including without limitation the rights
           * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
           * copies of the Software, and to permit persons to whom the Software is
           * furnished to do so, subject to the following conditions:
           *
           * The above copyright notice and this permission notice shall be included in
           * copies or substantial portions of the Software.
           *
           * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
           * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
           * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
           * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
           * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
           * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
           * SOFTWARE.
           */
          pragma solidity 0.6.12;
          /**
           * @notice The Ownable contract has an owner address, and provides basic
           * authorization control functions
           * @dev Forked from https://github.com/OpenZeppelin/openzeppelin-labs/blob/3887ab77b8adafba4a26ace002f3a684c1a3388b/upgradeability_ownership/contracts/ownership/Ownable.sol
           * Modifications:
           * 1. Consolidate OwnableStorage into this contract (7/13/18)
           * 2. Reformat, conform to Solidity 0.6 syntax, and add error messages (5/13/20)
           * 3. Make public functions external (5/27/20)
           */
          contract Ownable {
              // Owner of the contract
              address private _owner;
              /**
               * @dev Event to show ownership has been transferred
               * @param previousOwner representing the address of the previous owner
               * @param newOwner representing the address of the new owner
               */
              event OwnershipTransferred(address previousOwner, address newOwner);
              /**
               * @dev The constructor sets the original owner of the contract to the sender account.
               */
              constructor() public {
                  setOwner(msg.sender);
              }
              /**
               * @dev Tells the address of the owner
               * @return the address of the owner
               */
              function owner() external view returns (address) {
                  return _owner;
              }
              /**
               * @dev Sets a new owner address
               */
              function setOwner(address newOwner) internal {
                  _owner = newOwner;
              }
              /**
               * @dev Throws if called by any account other than the owner.
               */
              modifier onlyOwner() {
                  require(msg.sender == _owner, "Ownable: caller is not the owner");
                  _;
              }
              /**
               * @dev Allows the current owner to transfer control of the contract to a newOwner.
               * @param newOwner The address to transfer ownership to.
               */
              function transferOwnership(address newOwner) external onlyOwner {
                  require(
                      newOwner != address(0),
                      "Ownable: new owner is the zero address"
                  );
                  emit OwnershipTransferred(_owner, newOwner);
                  setOwner(newOwner);
              }
          }
          /**
           * SPDX-License-Identifier: Apache-2.0
           *
           * Copyright (c) 2023, Circle Internet Financial, LLC.
           *
           * Licensed under the Apache License, Version 2.0 (the "License");
           * you may not use this file except in compliance with the License.
           * You may obtain a copy of the License at
           *
           * http://www.apache.org/licenses/LICENSE-2.0
           *
           * Unless required by applicable law or agreed to in writing, software
           * distributed under the License is distributed on an "AS IS" BASIS,
           * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
           * See the License for the specific language governing permissions and
           * limitations under the License.
           */
          pragma solidity 0.6.12;
          import { SafeMath } from "@openzeppelin/contracts/math/SafeMath.sol";
          import { AbstractFiatTokenV1 } from "./AbstractFiatTokenV1.sol";
          import { Ownable } from "./Ownable.sol";
          import { Pausable } from "./Pausable.sol";
          import { Blacklistable } from "./Blacklistable.sol";
          /**
           * @title FiatToken
           * @dev ERC20 Token backed by fiat reserves
           */
          contract FiatTokenV1 is AbstractFiatTokenV1, Ownable, Pausable, Blacklistable {
              using SafeMath for uint256;
              string public name;
              string public symbol;
              uint8 public decimals;
              string public currency;
              address public masterMinter;
              bool internal initialized;
              /// @dev A mapping that stores the balance and blacklist states for a given address.
              /// The first bit defines whether the address is blacklisted (1 if blacklisted, 0 otherwise).
              /// The last 255 bits define the balance for the address.
              mapping(address => uint256) internal balanceAndBlacklistStates;
              mapping(address => mapping(address => uint256)) internal allowed;
              uint256 internal totalSupply_ = 0;
              mapping(address => bool) internal minters;
              mapping(address => uint256) internal minterAllowed;
              event Mint(address indexed minter, address indexed to, uint256 amount);
              event Burn(address indexed burner, uint256 amount);
              event MinterConfigured(address indexed minter, uint256 minterAllowedAmount);
              event MinterRemoved(address indexed oldMinter);
              event MasterMinterChanged(address indexed newMasterMinter);
              /**
               * @notice Initializes the fiat token contract.
               * @param tokenName       The name of the fiat token.
               * @param tokenSymbol     The symbol of the fiat token.
               * @param tokenCurrency   The fiat currency that the token represents.
               * @param tokenDecimals   The number of decimals that the token uses.
               * @param newMasterMinter The masterMinter address for the fiat token.
               * @param newPauser       The pauser address for the fiat token.
               * @param newBlacklister  The blacklister address for the fiat token.
               * @param newOwner        The owner of the fiat token.
               */
              function initialize(
                  string memory tokenName,
                  string memory tokenSymbol,
                  string memory tokenCurrency,
                  uint8 tokenDecimals,
                  address newMasterMinter,
                  address newPauser,
                  address newBlacklister,
                  address newOwner
              ) public {
                  require(!initialized, "FiatToken: contract is already initialized");
                  require(
                      newMasterMinter != address(0),
                      "FiatToken: new masterMinter is the zero address"
                  );
                  require(
                      newPauser != address(0),
                      "FiatToken: new pauser is the zero address"
                  );
                  require(
                      newBlacklister != address(0),
                      "FiatToken: new blacklister is the zero address"
                  );
                  require(
                      newOwner != address(0),
                      "FiatToken: new owner is the zero address"
                  );
                  name = tokenName;
                  symbol = tokenSymbol;
                  currency = tokenCurrency;
                  decimals = tokenDecimals;
                  masterMinter = newMasterMinter;
                  pauser = newPauser;
                  blacklister = newBlacklister;
                  setOwner(newOwner);
                  initialized = true;
              }
              /**
               * @dev Throws if called by any account other than a minter.
               */
              modifier onlyMinters() {
                  require(minters[msg.sender], "FiatToken: caller is not a minter");
                  _;
              }
              /**
               * @notice Mints fiat tokens to an address.
               * @param _to The address that will receive the minted tokens.
               * @param _amount The amount of tokens to mint. Must be less than or equal
               * to the minterAllowance of the caller.
               * @return True if the operation was successful.
               */
              function mint(address _to, uint256 _amount)
                  external
                  whenNotPaused
                  onlyMinters
                  notBlacklisted(msg.sender)
                  notBlacklisted(_to)
                  returns (bool)
              {
                  require(_to != address(0), "FiatToken: mint to the zero address");
                  require(_amount > 0, "FiatToken: mint amount not greater than 0");
                  uint256 mintingAllowedAmount = minterAllowed[msg.sender];
                  require(
                      _amount <= mintingAllowedAmount,
                      "FiatToken: mint amount exceeds minterAllowance"
                  );
                  totalSupply_ = totalSupply_.add(_amount);
                  _setBalance(_to, _balanceOf(_to).add(_amount));
                  minterAllowed[msg.sender] = mintingAllowedAmount.sub(_amount);
                  emit Mint(msg.sender, _to, _amount);
                  emit Transfer(address(0), _to, _amount);
                  return true;
              }
              /**
               * @dev Throws if called by any account other than the masterMinter
               */
              modifier onlyMasterMinter() {
                  require(
                      msg.sender == masterMinter,
                      "FiatToken: caller is not the masterMinter"
                  );
                  _;
              }
              /**
               * @notice Gets the minter allowance for an account.
               * @param minter The address to check.
               * @return The remaining minter allowance for the account.
               */
              function minterAllowance(address minter) external view returns (uint256) {
                  return minterAllowed[minter];
              }
              /**
               * @notice Checks if an account is a minter.
               * @param account The address to check.
               * @return True if the account is a minter, false if the account is not a minter.
               */
              function isMinter(address account) external view returns (bool) {
                  return minters[account];
              }
              /**
               * @notice Gets the remaining amount of fiat tokens a spender is allowed to transfer on
               * behalf of the token owner.
               * @param owner   The token owner's address.
               * @param spender The spender's address.
               * @return The remaining allowance.
               */
              function allowance(address owner, address spender)
                  external
                  override
                  view
                  returns (uint256)
              {
                  return allowed[owner][spender];
              }
              /**
               * @notice Gets the totalSupply of the fiat token.
               * @return The totalSupply of the fiat token.
               */
              function totalSupply() external override view returns (uint256) {
                  return totalSupply_;
              }
              /**
               * @notice Gets the fiat token balance of an account.
               * @param account  The address to check.
               * @return balance The fiat token balance of the account.
               */
              function balanceOf(address account)
                  external
                  override
                  view
                  returns (uint256)
              {
                  return _balanceOf(account);
              }
              /**
               * @notice Sets a fiat token allowance for a spender to spend on behalf of the caller.
               * @param spender The spender's address.
               * @param value   The allowance amount.
               * @return True if the operation was successful.
               */
              function approve(address spender, uint256 value)
                  external
                  virtual
                  override
                  whenNotPaused
                  notBlacklisted(msg.sender)
                  notBlacklisted(spender)
                  returns (bool)
              {
                  _approve(msg.sender, spender, value);
                  return true;
              }
              /**
               * @dev Internal function to set allowance.
               * @param owner     Token owner's address.
               * @param spender   Spender's address.
               * @param value     Allowance amount.
               */
              function _approve(
                  address owner,
                  address spender,
                  uint256 value
              ) internal override {
                  require(owner != address(0), "ERC20: approve from the zero address");
                  require(spender != address(0), "ERC20: approve to the zero address");
                  allowed[owner][spender] = value;
                  emit Approval(owner, spender, value);
              }
              /**
               * @notice Transfers tokens from an address to another by spending the caller's allowance.
               * @dev The caller must have some fiat token allowance on the payer's tokens.
               * @param from  Payer's address.
               * @param to    Payee's address.
               * @param value Transfer amount.
               * @return True if the operation was successful.
               */
              function transferFrom(
                  address from,
                  address to,
                  uint256 value
              )
                  external
                  override
                  whenNotPaused
                  notBlacklisted(msg.sender)
                  notBlacklisted(from)
                  notBlacklisted(to)
                  returns (bool)
              {
                  require(
                      value <= allowed[from][msg.sender],
                      "ERC20: transfer amount exceeds allowance"
                  );
                  _transfer(from, to, value);
                  allowed[from][msg.sender] = allowed[from][msg.sender].sub(value);
                  return true;
              }
              /**
               * @notice Transfers tokens from the caller.
               * @param to    Payee's address.
               * @param value Transfer amount.
               * @return True if the operation was successful.
               */
              function transfer(address to, uint256 value)
                  external
                  override
                  whenNotPaused
                  notBlacklisted(msg.sender)
                  notBlacklisted(to)
                  returns (bool)
              {
                  _transfer(msg.sender, to, value);
                  return true;
              }
              /**
               * @dev Internal function to process transfers.
               * @param from  Payer's address.
               * @param to    Payee's address.
               * @param value Transfer amount.
               */
              function _transfer(
                  address from,
                  address to,
                  uint256 value
              ) internal override {
                  require(from != address(0), "ERC20: transfer from the zero address");
                  require(to != address(0), "ERC20: transfer to the zero address");
                  require(
                      value <= _balanceOf(from),
                      "ERC20: transfer amount exceeds balance"
                  );
                  _setBalance(from, _balanceOf(from).sub(value));
                  _setBalance(to, _balanceOf(to).add(value));
                  emit Transfer(from, to, value);
              }
              /**
               * @notice Adds or updates a new minter with a mint allowance.
               * @param minter The address of the minter.
               * @param minterAllowedAmount The minting amount allowed for the minter.
               * @return True if the operation was successful.
               */
              function configureMinter(address minter, uint256 minterAllowedAmount)
                  external
                  whenNotPaused
                  onlyMasterMinter
                  returns (bool)
              {
                  minters[minter] = true;
                  minterAllowed[minter] = minterAllowedAmount;
                  emit MinterConfigured(minter, minterAllowedAmount);
                  return true;
              }
              /**
               * @notice Removes a minter.
               * @param minter The address of the minter to remove.
               * @return True if the operation was successful.
               */
              function removeMinter(address minter)
                  external
                  onlyMasterMinter
                  returns (bool)
              {
                  minters[minter] = false;
                  minterAllowed[minter] = 0;
                  emit MinterRemoved(minter);
                  return true;
              }
              /**
               * @notice Allows a minter to burn some of its own tokens.
               * @dev The caller must be a minter, must not be blacklisted, and the amount to burn
               * should be less than or equal to the account's balance.
               * @param _amount the amount of tokens to be burned.
               */
              function burn(uint256 _amount)
                  external
                  whenNotPaused
                  onlyMinters
                  notBlacklisted(msg.sender)
              {
                  uint256 balance = _balanceOf(msg.sender);
                  require(_amount > 0, "FiatToken: burn amount not greater than 0");
                  require(balance >= _amount, "FiatToken: burn amount exceeds balance");
                  totalSupply_ = totalSupply_.sub(_amount);
                  _setBalance(msg.sender, balance.sub(_amount));
                  emit Burn(msg.sender, _amount);
                  emit Transfer(msg.sender, address(0), _amount);
              }
              /**
               * @notice Updates the master minter address.
               * @param _newMasterMinter The address of the new master minter.
               */
              function updateMasterMinter(address _newMasterMinter) external onlyOwner {
                  require(
                      _newMasterMinter != address(0),
                      "FiatToken: new masterMinter is the zero address"
                  );
                  masterMinter = _newMasterMinter;
                  emit MasterMinterChanged(masterMinter);
              }
              /**
               * @inheritdoc Blacklistable
               */
              function _blacklist(address _account) internal override {
                  _setBlacklistState(_account, true);
              }
              /**
               * @inheritdoc Blacklistable
               */
              function _unBlacklist(address _account) internal override {
                  _setBlacklistState(_account, false);
              }
              /**
               * @dev Helper method that sets the blacklist state of an account.
               * @param _account         The address of the account.
               * @param _shouldBlacklist True if the account should be blacklisted, false if the account should be unblacklisted.
               */
              function _setBlacklistState(address _account, bool _shouldBlacklist)
                  internal
                  virtual
              {
                  _deprecatedBlacklisted[_account] = _shouldBlacklist;
              }
              /**
               * @dev Helper method that sets the balance of an account.
               * @param _account The address of the account.
               * @param _balance The new fiat token balance of the account.
               */
              function _setBalance(address _account, uint256 _balance) internal virtual {
                  balanceAndBlacklistStates[_account] = _balance;
              }
              /**
               * @inheritdoc Blacklistable
               */
              function _isBlacklisted(address _account)
                  internal
                  virtual
                  override
                  view
                  returns (bool)
              {
                  return _deprecatedBlacklisted[_account];
              }
              /**
               * @dev Helper method to obtain the balance of an account.
               * @param _account  The address of the account.
               * @return          The fiat token balance of the account.
               */
              function _balanceOf(address _account)
                  internal
                  virtual
                  view
                  returns (uint256)
              {
                  return balanceAndBlacklistStates[_account];
              }
          }
          /**
           * SPDX-License-Identifier: Apache-2.0
           *
           * Copyright (c) 2023, Circle Internet Financial, LLC.
           *
           * Licensed under the Apache License, Version 2.0 (the "License");
           * you may not use this file except in compliance with the License.
           * You may obtain a copy of the License at
           *
           * http://www.apache.org/licenses/LICENSE-2.0
           *
           * Unless required by applicable law or agreed to in writing, software
           * distributed under the License is distributed on an "AS IS" BASIS,
           * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
           * See the License for the specific language governing permissions and
           * limitations under the License.
           */
          pragma solidity 0.6.12;
          import { Ownable } from "./Ownable.sol";
          /**
           * @title Blacklistable Token
           * @dev Allows accounts to be blacklisted by a "blacklister" role
           */
          abstract contract Blacklistable is Ownable {
              address public blacklister;
              mapping(address => bool) internal _deprecatedBlacklisted;
              event Blacklisted(address indexed _account);
              event UnBlacklisted(address indexed _account);
              event BlacklisterChanged(address indexed newBlacklister);
              /**
               * @dev Throws if called by any account other than the blacklister.
               */
              modifier onlyBlacklister() {
                  require(
                      msg.sender == blacklister,
                      "Blacklistable: caller is not the blacklister"
                  );
                  _;
              }
              /**
               * @dev Throws if argument account is blacklisted.
               * @param _account The address to check.
               */
              modifier notBlacklisted(address _account) {
                  require(
                      !_isBlacklisted(_account),
                      "Blacklistable: account is blacklisted"
                  );
                  _;
              }
              /**
               * @notice Checks if account is blacklisted.
               * @param _account The address to check.
               * @return True if the account is blacklisted, false if the account is not blacklisted.
               */
              function isBlacklisted(address _account) external view returns (bool) {
                  return _isBlacklisted(_account);
              }
              /**
               * @notice Adds account to blacklist.
               * @param _account The address to blacklist.
               */
              function blacklist(address _account) external onlyBlacklister {
                  _blacklist(_account);
                  emit Blacklisted(_account);
              }
              /**
               * @notice Removes account from blacklist.
               * @param _account The address to remove from the blacklist.
               */
              function unBlacklist(address _account) external onlyBlacklister {
                  _unBlacklist(_account);
                  emit UnBlacklisted(_account);
              }
              /**
               * @notice Updates the blacklister address.
               * @param _newBlacklister The address of the new blacklister.
               */
              function updateBlacklister(address _newBlacklister) external onlyOwner {
                  require(
                      _newBlacklister != address(0),
                      "Blacklistable: new blacklister is the zero address"
                  );
                  blacklister = _newBlacklister;
                  emit BlacklisterChanged(blacklister);
              }
              /**
               * @dev Checks if account is blacklisted.
               * @param _account The address to check.
               * @return true if the account is blacklisted, false otherwise.
               */
              function _isBlacklisted(address _account)
                  internal
                  virtual
                  view
                  returns (bool);
              /**
               * @dev Helper method that blacklists an account.
               * @param _account The address to blacklist.
               */
              function _blacklist(address _account) internal virtual;
              /**
               * @dev Helper method that unblacklists an account.
               * @param _account The address to unblacklist.
               */
              function _unBlacklist(address _account) internal virtual;
          }
          /**
           * SPDX-License-Identifier: Apache-2.0
           *
           * Copyright (c) 2023, Circle Internet Financial, LLC.
           *
           * Licensed under the Apache License, Version 2.0 (the "License");
           * you may not use this file except in compliance with the License.
           * You may obtain a copy of the License at
           *
           * http://www.apache.org/licenses/LICENSE-2.0
           *
           * Unless required by applicable law or agreed to in writing, software
           * distributed under the License is distributed on an "AS IS" BASIS,
           * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
           * See the License for the specific language governing permissions and
           * limitations under the License.
           */
          pragma solidity 0.6.12;
          import { IERC20 } from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
          abstract contract AbstractFiatTokenV1 is IERC20 {
              function _approve(
                  address owner,
                  address spender,
                  uint256 value
              ) internal virtual;
              function _transfer(
                  address from,
                  address to,
                  uint256 value
              ) internal virtual;
          }
          /**
           * SPDX-License-Identifier: Apache-2.0
           *
           * Copyright (c) 2023, Circle Internet Financial, LLC.
           *
           * Licensed under the Apache License, Version 2.0 (the "License");
           * you may not use this file except in compliance with the License.
           * You may obtain a copy of the License at
           *
           * http://www.apache.org/licenses/LICENSE-2.0
           *
           * Unless required by applicable law or agreed to in writing, software
           * distributed under the License is distributed on an "AS IS" BASIS,
           * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
           * See the License for the specific language governing permissions and
           * limitations under the License.
           */
          pragma solidity 0.6.12;
          import { Ownable } from "../v1/Ownable.sol";
          import { IERC20 } from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
          import { SafeERC20 } from "@openzeppelin/contracts/token/ERC20/SafeERC20.sol";
          contract Rescuable is Ownable {
              using SafeERC20 for IERC20;
              address private _rescuer;
              event RescuerChanged(address indexed newRescuer);
              /**
               * @notice Returns current rescuer
               * @return Rescuer's address
               */
              function rescuer() external view returns (address) {
                  return _rescuer;
              }
              /**
               * @notice Revert if called by any account other than the rescuer.
               */
              modifier onlyRescuer() {
                  require(msg.sender == _rescuer, "Rescuable: caller is not the rescuer");
                  _;
              }
              /**
               * @notice Rescue ERC20 tokens locked up in this contract.
               * @param tokenContract ERC20 token contract address
               * @param to        Recipient address
               * @param amount    Amount to withdraw
               */
              function rescueERC20(
                  IERC20 tokenContract,
                  address to,
                  uint256 amount
              ) external onlyRescuer {
                  tokenContract.safeTransfer(to, amount);
              }
              /**
               * @notice Updates the rescuer address.
               * @param newRescuer The address of the new rescuer.
               */
              function updateRescuer(address newRescuer) external onlyOwner {
                  require(
                      newRescuer != address(0),
                      "Rescuable: new rescuer is the zero address"
                  );
                  _rescuer = newRescuer;
                  emit RescuerChanged(newRescuer);
              }
          }
          /**
           * SPDX-License-Identifier: Apache-2.0
           *
           * Copyright (c) 2023, Circle Internet Financial, LLC.
           *
           * Licensed under the Apache License, Version 2.0 (the "License");
           * you may not use this file except in compliance with the License.
           * You may obtain a copy of the License at
           *
           * http://www.apache.org/licenses/LICENSE-2.0
           *
           * Unless required by applicable law or agreed to in writing, software
           * distributed under the License is distributed on an "AS IS" BASIS,
           * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
           * See the License for the specific language governing permissions and
           * limitations under the License.
           */
          pragma solidity 0.6.12;
          import { FiatTokenV1 } from "../v1/FiatTokenV1.sol";
          import { Rescuable } from "./Rescuable.sol";
          /**
           * @title FiatTokenV1_1
           * @dev ERC20 Token backed by fiat reserves
           */
          contract FiatTokenV1_1 is FiatTokenV1, Rescuable {
          }
          /**
           * SPDX-License-Identifier: Apache-2.0
           *
           * Copyright (c) 2023, Circle Internet Financial, LLC.
           *
           * Licensed under the Apache License, Version 2.0 (the "License");
           * you may not use this file except in compliance with the License.
           * You may obtain a copy of the License at
           *
           * http://www.apache.org/licenses/LICENSE-2.0
           *
           * Unless required by applicable law or agreed to in writing, software
           * distributed under the License is distributed on an "AS IS" BASIS,
           * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
           * See the License for the specific language governing permissions and
           * limitations under the License.
           */
          pragma solidity 0.6.12;
          import { ECRecover } from "./ECRecover.sol";
          import { IERC1271 } from "../interface/IERC1271.sol";
          /**
           * @dev Signature verification helper that can be used instead of `ECRecover.recover` to seamlessly support both ECDSA
           * signatures from externally owned accounts (EOAs) as well as ERC1271 signatures from smart contract wallets.
           *
           * Adapted from https://github.com/OpenZeppelin/openzeppelin-contracts/blob/21bb89ef5bfc789b9333eb05e3ba2b7b284ac77c/contracts/utils/cryptography/SignatureChecker.sol
           */
          library SignatureChecker {
              /**
               * @dev Checks if a signature is valid for a given signer and data hash. If the signer is a smart contract, the
               * signature is validated against that smart contract using ERC1271, otherwise it's validated using `ECRecover.recover`.
               * @param signer        Address of the claimed signer
               * @param digest        Keccak-256 hash digest of the signed message
               * @param signature     Signature byte array associated with hash
               */
              function isValidSignatureNow(
                  address signer,
                  bytes32 digest,
                  bytes memory signature
              ) external view returns (bool) {
                  if (!isContract(signer)) {
                      return ECRecover.recover(digest, signature) == signer;
                  }
                  return isValidERC1271SignatureNow(signer, digest, signature);
              }
              /**
               * @dev Checks if a signature is valid for a given signer and data hash. The signature is validated
               * against the signer smart contract using ERC1271.
               * @param signer        Address of the claimed signer
               * @param digest        Keccak-256 hash digest of the signed message
               * @param signature     Signature byte array associated with hash
               *
               * NOTE: Unlike ECDSA signatures, contract signatures are revocable, and the outcome of this function can thus
               * change through time. It could return true at block N and false at block N+1 (or the opposite).
               */
              function isValidERC1271SignatureNow(
                  address signer,
                  bytes32 digest,
                  bytes memory signature
              ) internal view returns (bool) {
                  (bool success, bytes memory result) = signer.staticcall(
                      abi.encodeWithSelector(
                          IERC1271.isValidSignature.selector,
                          digest,
                          signature
                      )
                  );
                  return (success &&
                      result.length >= 32 &&
                      abi.decode(result, (bytes32)) ==
                      bytes32(IERC1271.isValidSignature.selector));
              }
              /**
               * @dev Checks if the input address is a smart contract.
               */
              function isContract(address addr) internal view returns (bool) {
                  uint256 size;
                  assembly {
                      size := extcodesize(addr)
                  }
                  return size > 0;
              }
          }
          /**
           * SPDX-License-Identifier: Apache-2.0
           *
           * Copyright (c) 2023, Circle Internet Financial, LLC.
           *
           * Licensed under the Apache License, Version 2.0 (the "License");
           * you may not use this file except in compliance with the License.
           * You may obtain a copy of the License at
           *
           * http://www.apache.org/licenses/LICENSE-2.0
           *
           * Unless required by applicable law or agreed to in writing, software
           * distributed under the License is distributed on an "AS IS" BASIS,
           * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
           * See the License for the specific language governing permissions and
           * limitations under the License.
           */
          pragma solidity 0.6.12;
          /**
           * @dev Signature message hash utilities for producing digests to be consumed by {ECDSA} recovery or signing.
           *
           * The library provides methods for generating a hash of a message that conforms to the
           * https://eips.ethereum.org/EIPS/eip-191[EIP 191] and https://eips.ethereum.org/EIPS/eip-712[EIP 712]
           * specifications.
           */
          library MessageHashUtils {
              /**
               * @dev Returns the keccak256 digest of an EIP-712 typed data (EIP-191 version `0x01`).
               * Adapted from https://github.com/OpenZeppelin/openzeppelin-contracts/blob/21bb89ef5bfc789b9333eb05e3ba2b7b284ac77c/contracts/utils/cryptography/MessageHashUtils.sol
               *
               * The digest is calculated from a `domainSeparator` and a `structHash`, by prefixing them with
               * `\\x19\\x01` and hashing the result. It corresponds to the hash signed by the
               * https://eips.ethereum.org/EIPS/eip-712[`eth_signTypedData`] JSON-RPC method as part of EIP-712.
               *
               * @param domainSeparator    Domain separator
               * @param structHash         Hashed EIP-712 data struct
               * @return digest            The keccak256 digest of an EIP-712 typed data
               */
              function toTypedDataHash(bytes32 domainSeparator, bytes32 structHash)
                  internal
                  pure
                  returns (bytes32 digest)
              {
                  assembly {
                      let ptr := mload(0x40)
                      mstore(ptr, "\\x19\\x01")
                      mstore(add(ptr, 0x02), domainSeparator)
                      mstore(add(ptr, 0x22), structHash)
                      digest := keccak256(ptr, 0x42)
                  }
              }
          }
          /**
           * SPDX-License-Identifier: Apache-2.0
           *
           * Copyright (c) 2023, Circle Internet Financial, LLC.
           *
           * Licensed under the Apache License, Version 2.0 (the "License");
           * you may not use this file except in compliance with the License.
           * You may obtain a copy of the License at
           *
           * http://www.apache.org/licenses/LICENSE-2.0
           *
           * Unless required by applicable law or agreed to in writing, software
           * distributed under the License is distributed on an "AS IS" BASIS,
           * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
           * See the License for the specific language governing permissions and
           * limitations under the License.
           */
          pragma solidity 0.6.12;
          /**
           * @title EIP712
           * @notice A library that provides EIP712 helper functions
           */
          library EIP712 {
              /**
               * @notice Make EIP712 domain separator
               * @param name      Contract name
               * @param version   Contract version
               * @param chainId   Blockchain ID
               * @return Domain separator
               */
              function makeDomainSeparator(
                  string memory name,
                  string memory version,
                  uint256 chainId
              ) internal view returns (bytes32) {
                  return
                      keccak256(
                          abi.encode(
                              // keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)")
                              0x8b73c3c69bb8fe3d512ecc4cf759cc79239f7b179b0ffacaa9a75d522b39400f,
                              keccak256(bytes(name)),
                              keccak256(bytes(version)),
                              chainId,
                              address(this)
                          )
                      );
              }
              /**
               * @notice Make EIP712 domain separator
               * @param name      Contract name
               * @param version   Contract version
               * @return Domain separator
               */
              function makeDomainSeparator(string memory name, string memory version)
                  internal
                  view
                  returns (bytes32)
              {
                  uint256 chainId;
                  assembly {
                      chainId := chainid()
                  }
                  return makeDomainSeparator(name, version, chainId);
              }
          }
          /**
           * SPDX-License-Identifier: Apache-2.0
           *
           * Copyright (c) 2023, Circle Internet Financial, LLC.
           *
           * Licensed under the Apache License, Version 2.0 (the "License");
           * you may not use this file except in compliance with the License.
           * You may obtain a copy of the License at
           *
           * http://www.apache.org/licenses/LICENSE-2.0
           *
           * Unless required by applicable law or agreed to in writing, software
           * distributed under the License is distributed on an "AS IS" BASIS,
           * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
           * See the License for the specific language governing permissions and
           * limitations under the License.
           */
          pragma solidity 0.6.12;
          /**
           * @title ECRecover
           * @notice A library that provides a safe ECDSA recovery function
           */
          library ECRecover {
              /**
               * @notice Recover signer's address from a signed message
               * @dev Adapted from: https://github.com/OpenZeppelin/openzeppelin-contracts/blob/65e4ffde586ec89af3b7e9140bdc9235d1254853/contracts/cryptography/ECDSA.sol
               * Modifications: Accept v, r, and s as separate arguments
               * @param digest    Keccak-256 hash digest of the signed message
               * @param v         v of the signature
               * @param r         r of the signature
               * @param s         s of the signature
               * @return Signer address
               */
              function recover(
                  bytes32 digest,
                  uint8 v,
                  bytes32 r,
                  bytes32 s
              ) internal pure returns (address) {
                  // EIP-2 still allows signature malleability for ecrecover(). Remove this possibility and make the signature
                  // unique. Appendix F in the Ethereum Yellow paper (https://ethereum.github.io/yellowpaper/paper.pdf), defines
                  // the valid range for s in (281): 0 < s < secp256k1n ÷ 2 + 1, and for v in (282): v ∈ {27, 28}. Most
                  // signatures from current libraries generate a unique signature with an s-value in the lower half order.
                  //
                  // If your library generates malleable signatures, such as s-values in the upper range, calculate a new s-value
                  // with 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 - s1 and flip v from 27 to 28 or
                  // vice versa. If your library also generates signatures with 0/1 for v instead 27/28, add 27 to v to accept
                  // these malleable signatures as well.
                  if (
                      uint256(s) >
                      0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0
                  ) {
                      revert("ECRecover: invalid signature 's' value");
                  }
                  if (v != 27 && v != 28) {
                      revert("ECRecover: invalid signature 'v' value");
                  }
                  // If the signature is valid (and not malleable), return the signer address
                  address signer = ecrecover(digest, v, r, s);
                  require(signer != address(0), "ECRecover: invalid signature");
                  return signer;
              }
              /**
               * @notice Recover signer's address from a signed message
               * @dev Adapted from: https://github.com/OpenZeppelin/openzeppelin-contracts/blob/0053ee040a7ff1dbc39691c9e67a69f564930a88/contracts/utils/cryptography/ECDSA.sol
               * @param digest    Keccak-256 hash digest of the signed message
               * @param signature Signature byte array associated with hash
               * @return Signer address
               */
              function recover(bytes32 digest, bytes memory signature)
                  internal
                  pure
                  returns (address)
              {
                  require(signature.length == 65, "ECRecover: invalid signature length");
                  bytes32 r;
                  bytes32 s;
                  uint8 v;
                  // ecrecover takes the signature parameters, and the only way to get them
                  // currently is to use assembly.
                  /// @solidity memory-safe-assembly
                  assembly {
                      r := mload(add(signature, 0x20))
                      s := mload(add(signature, 0x40))
                      v := byte(0, mload(add(signature, 0x60)))
                  }
                  return recover(digest, v, r, s);
              }
          }
          /**
           * SPDX-License-Identifier: Apache-2.0
           *
           * Copyright (c) 2023, Circle Internet Financial, LLC.
           *
           * Licensed under the Apache License, Version 2.0 (the "License");
           * you may not use this file except in compliance with the License.
           * You may obtain a copy of the License at
           *
           * http://www.apache.org/licenses/LICENSE-2.0
           *
           * Unless required by applicable law or agreed to in writing, software
           * distributed under the License is distributed on an "AS IS" BASIS,
           * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
           * See the License for the specific language governing permissions and
           * limitations under the License.
           */
          pragma solidity 0.6.12;
          /**
           * @dev Interface of the ERC1271 standard signature validation method for
           * contracts as defined in https://eips.ethereum.org/EIPS/eip-1271[ERC-1271].
           */
          interface IERC1271 {
              /**
               * @dev Should return whether the signature provided is valid for the provided data
               * @param hash          Hash of the data to be signed
               * @param signature     Signature byte array associated with the provided data hash
               * @return magicValue   bytes4 magic value 0x1626ba7e when function passes
               */
              function isValidSignature(bytes32 hash, bytes memory signature)
                  external
                  view
                  returns (bytes4 magicValue);
          }