ETH Price: $2,640.59 (+3.33%)

Transaction Decoder

Block:
20181725 at Jun-27-2024 08:07:11 AM +UTC
Transaction Fee:
0.000549855379899298 ETH $1.45
Gas Used:
106,397 Gas / 5.167959434 Gwei

Emitted Events:

188 PlatformToken.Transfer( from=[Receiver] PlatformVesting, to=[Sender] 0x9270003ca7b946afa04b4c237c27e47000a60408, value=282314285700000000000 )
189 PlatformVesting.Claim( vestingId=594, wallet=[Sender] 0x9270003ca7b946afa04b4c237c27e47000a60408, amount=282314285700000000000 )

Account State Difference:

  Address   Before After State Difference Code
(Titan Builder)
7.712725167789548753 Eth7.712786272408884769 Eth0.000061104619336016
0x9270003C...000A60408
0.168099322683293413 Eth
Nonce: 33
0.167549467303394115 Eth
Nonce: 34
0.000549855379899298
0x9ff58067...325Df138E
0xF3ff9680...Bc6299215

Execution Trace

PlatformVesting.claim( wallet=0x9270003CA7B946afa04B4C237c27E47000A60408 )
  • PlatformToken.transfer( to=0x9270003CA7B946afa04B4C237c27E47000A60408, amount=282314285700000000000 ) => ( True )
    File 1 of 2: PlatformVesting
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts v4.4.1 (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() {
            // On the first call to nonReentrant, _notEntered will be true
            require(_status != _ENTERED, "ReentrancyGuard: reentrant call");
            // Any calls to nonReentrant after this point will fail
            _status = _ENTERED;
            _;
            // By storing the original value once again, a refund is triggered (see
            // https://eips.ethereum.org/EIPS/eip-2200)
            _status = _NOT_ENTERED;
        }
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/draft-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.
     */
    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].
         */
        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 v4.6.0) (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 v4.7.0) (token/ERC20/utils/SafeERC20.sol)
    pragma solidity ^0.8.0;
    import "../IERC20.sol";
    import "../extensions/draft-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;
        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'
            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) + value;
            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
        }
        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");
                uint256 newAllowance = oldAllowance - value;
                _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
            }
        }
        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");
            if (returndata.length > 0) {
                // Return data is optional
                require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
            }
        }
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v4.7.0) (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
         * ====
         *
         * [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://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");
            (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");
            (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");
            (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");
            (bool success, bytes memory returndata) = target.delegatecall(data);
            return verifyCallResult(success, returndata, errorMessage);
        }
        /**
         * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
         * revert reason 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 {
                // 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 v4.6.0) (utils/math/SafeMath.sol)
    pragma solidity ^0.8.0;
    // CAUTION
    // This version of SafeMath should only be used with Solidity 0.8 or later,
    // because it relies on the compiler's built in overflow checks.
    /**
     * @dev Wrappers over Solidity's arithmetic operations.
     *
     * NOTE: `SafeMath` is generally not needed starting with Solidity 0.8, since the compiler
     * now has built in overflow checking.
     */
    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) {
            unchecked {
                uint256 c = a + b;
                if (c < a) return (false, 0);
                return (true, c);
            }
        }
        /**
         * @dev Returns the subtraction of two unsigned integers, with an overflow flag.
         *
         * _Available since v3.4._
         */
        function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            unchecked {
                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) {
            unchecked {
                // 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) {
            unchecked {
                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) {
            unchecked {
                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) {
            return a + b;
        }
        /**
         * @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) {
            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) {
            return a * b;
        }
        /**
         * @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.
         *
         * Requirements:
         *
         * - The divisor cannot be zero.
         */
        function div(uint256 a, uint256 b) internal pure returns (uint256) {
            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) {
            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) {
            unchecked {
                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.
         *
         * 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) {
            unchecked {
                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) {
            unchecked {
                require(b > 0, errorMessage);
                return a % b;
            }
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity 0.8.19;
    import "../admin_panel/PlatformAdminPanel.sol";
    /**
     * @title Abstract contract from which platform contracts with admin function are inherited
     * @dev Contains the platform admin panel
     * Contains modifier that checks whether sender is platform admin, use platform admin panel
     */
    abstract contract PlatformAccessController {
        address public _panel;
        error CallerNotAdmin();
        error AlreadyInitialized();
        function _initiatePlatformAccessController(address adminPanel) internal {
            if(address(_panel) != address(0))
                revert AlreadyInitialized();
            _panel = adminPanel;
        }
        /**
         * @dev Modifier that makes function available for platform admins only
         */
        modifier onlyPlatformAdmin() {
            if(!PlatformAdminPanel(_panel).isAdmin(msgSender()))
                revert CallerNotAdmin();
            _;
        }
        function _isAdmin() internal view returns (bool) {
            return PlatformAdminPanel(_panel).isAdmin(msgSender());
        }
        function msgSender() internal view virtual returns (address) {
            return msg.sender;
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity 0.8.19;
    interface IPlatformAdminPanel {
        function isAdmin(address wallet) external view returns (bool);
    }
    // SPDX-License-Identifier: MIT
    pragma solidity 0.8.19;
    import "./Iplatform_admin_panel/IPlatformAdminPanel.sol";
    /**
     * @title Platform admins holder contract
     * @notice Used to check accessibility of senders to admin functions in platform contracts
     */
    contract PlatformAdminPanel is IPlatformAdminPanel {
        /**
         * @notice Emit during root admin set and reset
         */
        event SetRootAdmin(address indexed wallet);
        event InsertAdminList(address[] adminList);
        event RemoveAdminList(address[] adminList);
        mapping(address => bool) private _adminMap;
        address private _rootAdmin;
        modifier onlyRootAdmin() {
            require(_rootAdmin == msg.sender, "sender is not root admin");
            _;
        }
        /**
         * @notice Specify the root admin, only he has the rights to add and remove admins
         */
        constructor(address rootAdminWallet) {
            _setRootAdmin(rootAdminWallet);
        }
        /**
         * @notice Needed to determine if the user has admin rights for platform contracts
         */
        function isAdmin(address wallet)
            external
            view
            virtual
            override
            returns (bool)
        {
            return wallet == _rootAdmin || _adminMap[wallet];
        }
        function rootAdmin() external view returns (address) {
            return _rootAdmin;
        }
        /**
         * @notice Only root admin can call
         */
        function insertAdminList(address[] calldata adminList)
            external
            onlyRootAdmin
        {
            require(0 < adminList.length, "empty admin list");
            uint256 index = adminList.length;
            while (0 < index) {
                --index;
                _adminMap[adminList[index]] = true;
            }
            emit InsertAdminList(adminList);
        }
        /**
         * @notice Only root admin can call
         */
        function removeAdminList(address[] calldata adminList)
            external
            onlyRootAdmin
        {
            require(0 < adminList.length, "empty admin list");
            uint256 index = adminList.length;
            while (0 < index) {
                --index;
                _adminMap[adminList[index]] = false;
            }
            emit RemoveAdminList(adminList);
        }
        /**
         * @notice Only root admin can call
         */
        function setRootAdmin(address rootAdminWallet) external onlyRootAdmin {
            _setRootAdmin(rootAdminWallet);
        }
        function _setRootAdmin(address wallet) private {
            require(wallet != address(0), "wallet is zero address");
            _rootAdmin = wallet;
            emit SetRootAdmin(wallet);
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity 0.8.19;
    interface IPlatformToken {
        function specialTransferFrom(
            address from,
            uint256 value,
            uint256 validAfter,
            uint256 validBefore,
            bytes32 nonce,
            uint8 v,
            bytes32 r,
            bytes32 s
        ) external;
    }
    // SPDX-License-Identifier: MIT
    pragma solidity 0.8.19;
    interface IPlatformVesting {
        function amountForClaim(address wallet, uint256 timestampInSeconds) external view returns (uint256 amount);
        function claim(address wallet) external;
    }
    // SPDX-License-Identifier: MIT
    pragma solidity 0.8.19;
    import "../access_controller/PlatformAccessController.sol";
    import "../token/IplatformToken/IPlatformToken.sol";
    import {ReentrancyGuard} from "@openzeppelin/contracts/security/ReentrancyGuard.sol";
    import { SafeMath } from "@openzeppelin/contracts/utils/math/SafeMath.sol";
    import {SafeERC20, IERC20} from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
    import "./IPlatformVesting/IPlatformVesting.sol";
    /**
     * @notice Separate vesting pool, each with separate liquidity, whitelists and parameters
     */
    contract PlatformVesting is PlatformAccessController, ReentrancyGuard, IPlatformVesting {
        using SafeMath for uint256;
        using SafeERC20 for IERC20;
        event InsertVestingList(address indexed admin, uint256 vestingCount);
        /**
         * @notice Emit during vesting vesting liquidity increasing
         * Liquidity of the vesting decreases
         * @param admin Platform admin which do this action
         * @param vestingId The vesting id
         * @param amount The PROPC token amount which add to vesting free amount
         */
        event IncreaseLiquidity(
            address indexed admin,
            uint256 indexed vestingId,
            uint256 amount
        );
        /**
         * @notice Emit during vesting vesting liquidity decreasing process
         * Liquidity of the vesting increases
         * @param admin Platform admin which do this action
         * @param amount The PROPC token amount which rem from vesting free amount
         */
        event DecreaseLiquidity(
            address indexed admin,
            uint256 amount
        );
        event InsertWalletListToVesting(
            address indexed admin,
            uint256 indexed vestingId,
            address[] walletList
        );
        event RemoveWalletListFromVesting(
            address indexed admin,
            uint256 indexed vestingId,
            address[] walletList
        );
        event TGESet(
            uint256 tgeDate,
            uint256 timestamp
        );
        event UpdateTokenAddress(
            address _address,
            uint256 timestamp
        );
        event VestingRemoved(
            uint256 id,
            uint256 timestamp
        );
        event VestingAdded(
            uint256 amountForUser,
            uint256 tgeAmountForUser,
            uint256 startTime,
            uint256 tickCount,
            uint256 tickDuration,
            uint256 timestamp
        );
        /**
         * @notice Emit when user claim his PROPC from vesting
         * @param vestingId The vesting id
         * @param wallet The user wallet
         * @param amount The PROPC token amount which user save
         */
        event Claim(
            uint256 indexed vestingId,
            address indexed wallet,
            uint256 amount
        );
        struct VestingProperties {
            uint256 amountForUser;
            uint256 tgeAmountForUser;
            uint256 startTime;
            uint256 tickCount;
            uint256 tickDuration;
            uint256 unallocatedAmount;
            bool active;
        }
        struct UserProperties {
            bool isActive;
            uint256 spentAmount;
            uint256 vestingId;
            bool tgeClaimed;
        }
        error InsufficientBalance();
        error InvalidTimestamp();
        error ZeroAddress();
        error ZeroAmount();
        error OutOfBounds();
        error EmptyArray();
        error ArraySizeDoesNotMatch();
        error VestingDoesNotExist();
        error UserAlreadyActive();
        error UserNotActive();
        error NoClaimAvailable();
        error VestingAlreadyActive();
        error StartBeforeNow();
        error StartBeforeTGE();
        error TicksMissing();
        error FatalError(string message);
        struct VestingLink {
            address user;
            bool active;
        }
        uint256 private constant TOTAL_SHARE = 100_000;
        uint256 public tgeStartDate;
        address private _token;
        uint256 public _vestingCount;
        uint256 public totalRemainingAllocatedAmount;
        mapping(uint256 => VestingProperties) private _vestingMap;
        mapping(uint256 => VestingLink) private _vestingToUser;
        mapping(address => UserProperties) private _userMapping;
        modifier existingVesting(uint256 vestingId) {
            require(vestingId <= _vestingCount, "vesting does not exist");
            _;
        }
        constructor(address adminPanel) {
            if(adminPanel == address(0))
                revert ZeroAddress();
            _initiatePlatformAccessController(adminPanel);
        }
        function setTgeDate(uint256 timestamp) external onlyPlatformAdmin {
            if(timestamp < block.timestamp)
                revert InvalidTimestamp();
            tgeStartDate = timestamp;
            emit TGESet(timestamp, block.timestamp);
        }
        function updateTokenAddress(address token) external onlyPlatformAdmin {
            if(token == address(0))
                revert ZeroAddress();
            _token = token;
            emit UpdateTokenAddress(token, block.timestamp);
        }
        /**
         * @notice Get vesting pool properties list
         * vesting.amountForUser   Total PROPC amount which user can claim
         * vesting.tgeAmountForUser   PROPC amount which user can claim immediately after the `tgeStartDate`
         * vesting.startTime   The moment after that users can start claiming tick by tick
         * vesting.tickCount   The number of ticks that must pass to fully unlock funds
         * Each tick unlocks a proportional amount
         * vesting.tickDuration   Tick duration on seconds
         * vesting.unallocatedAmount PROPC that has not yet been assigned to any users
         * Grows when users are deleted and liquidity is increased by the admin
         * Falls when users are deleted and the liquidity is reduced by the admin
         */
        function vestingPropertiesList()
            external
            view
            returns (VestingProperties[] memory vestingList)
        {
            uint256 count = _vestingCount;
            vestingList = new VestingProperties[](count);
            while (0 < count) {
                --count;
                vestingList[count] = _vestingMap[count];
            }
        }
        /**
         * @notice Get properties list for the user
         * @param wallet User wallet
         * user.isActive   Indicates whether the user is on the whitelist or not
         * Admin can add or remove users.
         * user.spentAmount   Amount that was branded by the user or seized as staking fee
         */
        function userPropertiesList(address wallet)
            external
            view
            returns (UserProperties memory userProperties)
        {
            userProperties = _userMapping[wallet];
        }
        /**
         * @notice Get possible claim amount for user list for vesting pool
         * @param wallet User wallet
         * @param timestampInSeconds Time at which they plan to make claim
         */
        function amountForClaim(address wallet, uint256 timestampInSeconds)
            external
            view
            returns (uint256 amount)
        {
            UserProperties storage user = _userMapping[wallet];
            VestingProperties storage vesting = _vestingMap[user.vestingId];
            amount = _amountForClaim(
                vesting,
                user,
                timestampInSeconds
            );
        }
        /**
         * @notice Only platform admin can do
         * If 0 < vesting.unallocatedAmount amount will be transfer from sender wallet
         */
        function insertVestingList(
            VestingProperties[] calldata vestingList
        ) external onlyPlatformAdmin {
            uint256 count = _vestingCount;
            if(vestingList.length == 0)
                revert EmptyArray();
            uint256 liquidity;
            uint256 index = vestingList.length;
            while (0 < index) {
                --index;
                liquidity += _setVesting(count + index, vestingList[index]);
            }
            _vestingCount += vestingList.length;
            if (liquidity > 0) {
                totalRemainingAllocatedAmount += liquidity;
                emit InsertVestingList(msgSender(), vestingList.length);
            }
        }
        function removeVesting(uint256 vestingId) external onlyPlatformAdmin {
            if(vestingId >= _vestingCount)
                revert OutOfBounds();
            VestingProperties storage vp = _vestingMap[vestingId];
            VestingLink storage vl = _vestingToUser[vestingId];
            UserProperties storage up = _userMapping[vl.user];
            if(!vp.active)
                revert VestingDoesNotExist();
            if(vp.amountForUser < up.spentAmount)
                revert FatalError("user exceeded maximum spending amount");
            uint256 remainingPayoutAmount = vp.amountForUser - up.spentAmount;
            if(totalRemainingAllocatedAmount < remainingPayoutAmount)
                revert FatalError("less balance than allocated amount");
            totalRemainingAllocatedAmount -= remainingPayoutAmount;
            delete _userMapping[vl.user];
            delete _vestingMap[vestingId];
            delete _vestingToUser[vestingId];
            emit VestingRemoved(vestingId, block.timestamp);
        }
        /**
         * @notice Only platform admin can do
         * @param vestingId Target vesting pool id
         * @param amount Target additional liquidity amount
         * Amount will be transfer from sender wallet
         */
        function increaseLiquidity(
            uint256 vestingId,
            uint256 amount,
            uint256 validAfter,
            uint256 validBefore,
            bytes32 nonce,
            uint8 v,
            bytes32 r,
            bytes32 s
        ) external onlyPlatformAdmin existingVesting(vestingId) nonReentrant {
            if(amount == 0)
                revert ZeroAmount();
            VestingProperties storage vesting = _vestingMap[vestingId];
            address admin = msgSender();
            IPlatformToken(_token).specialTransferFrom(
                admin,
                amount,
                validAfter,
                validBefore,
                nonce,
                v,
                r,
                s
            );
            vesting.unallocatedAmount += amount;
            emit IncreaseLiquidity(admin, vestingId, amount);
        }
        /**
         * @notice Only platform admin can do
         * @param amount Target removal liquidity amount
         * Amount will be transfer to sender wallet
         */
        function decreaseLiquidity(uint256 amount)
            external
            onlyPlatformAdmin
        {
            if(amount == 0)
                revert ZeroAmount();
            uint256 availableSenderBalance = IERC20(_token).balanceOf(address(this));
            if(amount > availableSenderBalance)
                revert InsufficientBalance();
            if(totalRemainingAllocatedAmount > availableSenderBalance)
                revert FatalError("balance less than allocated amount");
            uint256 availableBalance = availableSenderBalance - totalRemainingAllocatedAmount;
            if(amount > availableBalance)
                revert InsufficientBalance();
            address admin = msgSender();
            IERC20(_token).safeTransfer(admin, amount);
            emit DecreaseLiquidity(admin, amount);
        }
        function insertWalletListToVesting(
            uint256[] calldata vestingIdList,
            address[] calldata walletList
        ) external onlyPlatformAdmin {
            if(walletList.length != vestingIdList.length)
                revert ArraySizeDoesNotMatch();
            if(walletList.length == 0)
                revert EmptyArray();
            uint256 decrease;
            uint256 index = walletList.length;
            while (0 < index) {
                --index;
                uint256 vestingId = vestingIdList[index];
                if(vestingId >= _vestingCount)
                    revert VestingDoesNotExist();
                VestingProperties storage vesting = _vestingMap[vestingId];
                uint256 amountForUser = vesting.amountForUser;
                address wallet = walletList[index];
                UserProperties storage user = _userMapping[wallet];
                if(user.isActive)
                    revert UserAlreadyActive();
                user.isActive = true;
                user.vestingId = vestingId;
                VestingLink storage vl = _vestingToUser[vestingId];
                if(vl.active)
                    revert VestingAlreadyActive();
                vl.user = wallet;
                vl.active = true;
                decrease = amountForUser - user.spentAmount;
                uint256 oldUnallocatedAmount = vesting.unallocatedAmount;
                if(decrease > oldUnallocatedAmount)
                    revert InsufficientBalance();
                vesting.unallocatedAmount = oldUnallocatedAmount - decrease;
                emit InsertWalletListToVesting(msgSender(), vestingId, walletList);
            }
        }
        function removeWalletListFromVesting(
            address[] calldata walletList
        ) external onlyPlatformAdmin {
            if(walletList.length == 0)
                revert EmptyArray();
            uint256 increasing;
            uint256 index = walletList.length;
            while (0 < index) {
                --index;
                address wallet = walletList[index];
                UserProperties storage user = _userMapping[wallet];
                uint256 vestingId = user.vestingId;
                VestingProperties storage vesting = _vestingMap[vestingId];
                uint256 amountForUser = vesting.amountForUser;
                if(!user.isActive)
                    revert UserNotActive();
                user.isActive = false;
                VestingLink storage vl = _vestingToUser[vestingId];
                vl.user = address(0);
                vl.active = false;
                increasing = amountForUser - user.spentAmount;
                vesting.unallocatedAmount += increasing;
                emit RemoveWalletListFromVesting(msgSender(), vestingId, walletList);
            }
        }
        /**
         * @notice Claim possible for user amount from the pool
         * If possible amounts equal to zero will revert
         * @param wallet User wallet
         */
        function claim(address wallet) external {
            _claim(wallet);
        }
        function _claim(address wallet) private {
            UserProperties storage user = _userMapping[wallet];
            VestingProperties storage vesting = _vestingMap[user.vestingId];
            uint256 claimAmount = _amountForClaim(vesting, user, block.timestamp);
            if(claimAmount == 0)
                revert NoClaimAvailable();
            user.spentAmount += claimAmount;
            uint256 vestingId = user.vestingId;
            totalRemainingAllocatedAmount -= claimAmount;
            IERC20(_token).safeTransfer(wallet, claimAmount);
            emit Claim(vestingId, wallet, claimAmount);
        }
        /**
        * @notice allows to individually send the TGE amount to a participant
        */
        function distributeAmount(uint256 vestingId) private {
            if(vestingId >= _vestingCount)
                revert OutOfBounds();
            VestingLink memory vl = _vestingToUser[vestingId];
            if(vl.active)   {
                _claim(vl.user);
            }
        }
        /**
        * @notice allows to airdrop currently available amounts to all vesting wallets
        * @param batchSize the number of people being airdropped in this call
        * @param offset the offset to select the correct batch
        */
        function airdrop(uint256 batchSize, uint256 offset) external onlyPlatformAdmin {
            if(offset > _vestingCount)
                revert OutOfBounds();
            uint256 index = _vestingCount - offset;
            while (0 < index) {
                --index;
                if(batchSize == 0)
                    return;
                distributeAmount(index);
                batchSize--;
            }
        }
        function _share(
            uint256 amount,
            uint256 share,
            uint256 total
        ) private pure returns (uint256) {
            return (amount * share) / total;
        }
        /**
         * @notice Returns the total amount claimable until the nowPoint point in time
         * @param vesting schedule to calculate amount for
         * @param user to retrieve the already spent amount
         * @param nowTime point in time to check for
         */
        function _amountForClaim(
            VestingProperties storage vesting,
            UserProperties storage user,
            uint256 nowTime
        ) private view returns (uint256) {
            uint256 startTime = vesting.startTime;
            if (!user.isActive) {
                return 0;
            }
            if (nowTime < tgeStartDate) {
                return 0;
            } else if (nowTime >= tgeStartDate && nowTime < startTime) {
                return vesting.tgeAmountForUser - user.spentAmount;
            }
            uint256 tickCount = vesting.tickCount;
            uint256 tick = (nowTime - startTime) / vesting.tickDuration + 1; // at start time, the first tick is available
            uint256 amount = vesting.tgeAmountForUser;
            uint256 rest = vesting.amountForUser - amount;
            if (tick < tickCount) {
                uint256 share = _share(TOTAL_SHARE, tick, tickCount);
                amount += _share(rest, share, TOTAL_SHARE);
            } else {
                amount += rest;
            }
            uint256 alreadyClaimed = user.spentAmount;
            if (amount <= alreadyClaimed) {
                return 0;
            }
            return amount - alreadyClaimed;
        }
        function _setVesting(uint256 vestingId, VestingProperties calldata setting)
            private
            returns (uint256 liquidity)
        {
            if(setting.tgeAmountForUser > setting.amountForUser)
                revert FatalError("tge amount greater than total amount");
            if(setting.startTime <= block.timestamp)
                revert StartBeforeNow();
            if(setting.startTime < tgeStartDate)
                revert StartBeforeTGE();
            if (setting.tgeAmountForUser < setting.amountForUser) {
                if(0 == setting.tickCount || setting.tickDuration == 0)
                    revert TicksMissing();
            }
            _vestingMap[vestingId] = setting;
            liquidity = setting.unallocatedAmount;
            emit VestingAdded(
                setting.amountForUser,
                setting.tgeAmountForUser,
                setting.startTime,
                setting.tickCount,
                setting.tickDuration,
                block.timestamp
            );
        }
    }
    

    File 2 of 2: PlatformToken
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/draft-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.
     */
    interface IERC20PermitUpgradeable {
        /**
         * @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].
         */
        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 v4.6.0) (token/ERC20/IERC20.sol)
    pragma solidity ^0.8.0;
    /**
     * @dev Interface of the ERC20 standard as defined in the EIP.
     */
    interface IERC20Upgradeable {
        /**
         * @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 v4.8.0) (token/ERC20/utils/SafeERC20.sol)
    pragma solidity ^0.8.0;
    import "../IERC20Upgradeable.sol";
    import "../extensions/draft-IERC20PermitUpgradeable.sol";
    import "../../../utils/AddressUpgradeable.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 SafeERC20Upgradeable {
        using AddressUpgradeable for address;
        function safeTransfer(
            IERC20Upgradeable token,
            address to,
            uint256 value
        ) internal {
            _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
        }
        function safeTransferFrom(
            IERC20Upgradeable 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(
            IERC20Upgradeable 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));
        }
        function safeIncreaseAllowance(
            IERC20Upgradeable token,
            address spender,
            uint256 value
        ) internal {
            uint256 newAllowance = token.allowance(address(this), spender) + value;
            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
        }
        function safeDecreaseAllowance(
            IERC20Upgradeable token,
            address spender,
            uint256 value
        ) internal {
            unchecked {
                uint256 oldAllowance = token.allowance(address(this), spender);
                require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
                uint256 newAllowance = oldAllowance - value;
                _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
            }
        }
        function safePermit(
            IERC20PermitUpgradeable 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(IERC20Upgradeable 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
                require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
            }
        }
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v4.8.0) (utils/Address.sol)
    pragma solidity ^0.8.1;
    /**
     * @dev Collection of functions related to the address type
     */
    library AddressUpgradeable {
        /**
         * @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
         * ====
         *
         * [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://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");
            (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 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 v4.4.1 (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() {
            // On the first call to nonReentrant, _notEntered will be true
            require(_status != _ENTERED, "ReentrancyGuard: reentrant call");
            // Any calls to nonReentrant after this point will fail
            _status = _ENTERED;
            _;
            // By storing the original value once again, a refund is triggered (see
            // https://eips.ethereum.org/EIPS/eip-2200)
            _status = _NOT_ENTERED;
        }
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v4.7.0) (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.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How
     * to implement supply mechanisms].
     *
     * 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}.
         *
         * The default value of {decimals} is 18. To select a different value for
         * {decimals} you should overload it.
         *
         * 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 value {ERC20} uses, unless this function is
         * 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;
            }
            _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;
            _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;
            }
            _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 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 v4.6.0) (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 v4.7.0) (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
         * ====
         *
         * [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://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");
            (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");
            (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");
            (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");
            (bool success, bytes memory returndata) = target.delegatecall(data);
            return verifyCallResult(success, returndata, errorMessage);
        }
        /**
         * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
         * revert reason 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 {
                // 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 v4.4.1 (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;
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity 0.8.19;
    import "../admin_panel/PlatformAdminPanel.sol";
    /**
     * @title Abstract contract from which platform contracts with admin function are inherited
     * @dev Contains the platform admin panel
     * Contains modifier that checks whether sender is platform admin, use platform admin panel
     */
    abstract contract PlatformAccessController {
        address public _panel;
        error CallerNotAdmin();
        error AlreadyInitialized();
        function _initiatePlatformAccessController(address adminPanel) internal {
            if(address(_panel) != address(0))
                revert AlreadyInitialized();
            _panel = adminPanel;
        }
        /**
         * @dev Modifier that makes function available for platform admins only
         */
        modifier onlyPlatformAdmin() {
            if(!PlatformAdminPanel(_panel).isAdmin(msgSender()))
                revert CallerNotAdmin();
            _;
        }
        function _isAdmin() internal view returns (bool) {
            return PlatformAdminPanel(_panel).isAdmin(msgSender());
        }
        function msgSender() internal view virtual returns (address) {
            return msg.sender;
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity 0.8.19;
    interface IPlatformAdminPanel {
        function isAdmin(address wallet) external view returns (bool);
    }
    // SPDX-License-Identifier: MIT
    pragma solidity 0.8.19;
    import "./Iplatform_admin_panel/IPlatformAdminPanel.sol";
    /**
     * @title Platform admins holder contract
     * @notice Used to check accessibility of senders to admin functions in platform contracts
     */
    contract PlatformAdminPanel is IPlatformAdminPanel {
        /**
         * @notice Emit during root admin set and reset
         */
        event SetRootAdmin(address indexed wallet);
        event InsertAdminList(address[] adminList);
        event RemoveAdminList(address[] adminList);
        mapping(address => bool) private _adminMap;
        address private _rootAdmin;
        modifier onlyRootAdmin() {
            require(_rootAdmin == msg.sender, "sender is not root admin");
            _;
        }
        /**
         * @notice Specify the root admin, only he has the rights to add and remove admins
         */
        constructor(address rootAdminWallet) {
            _setRootAdmin(rootAdminWallet);
        }
        /**
         * @notice Needed to determine if the user has admin rights for platform contracts
         */
        function isAdmin(address wallet)
            external
            view
            virtual
            override
            returns (bool)
        {
            return wallet == _rootAdmin || _adminMap[wallet];
        }
        function rootAdmin() external view returns (address) {
            return _rootAdmin;
        }
        /**
         * @notice Only root admin can call
         */
        function insertAdminList(address[] calldata adminList)
            external
            onlyRootAdmin
        {
            require(0 < adminList.length, "empty admin list");
            uint256 index = adminList.length;
            while (0 < index) {
                --index;
                _adminMap[adminList[index]] = true;
            }
            emit InsertAdminList(adminList);
        }
        /**
         * @notice Only root admin can call
         */
        function removeAdminList(address[] calldata adminList)
            external
            onlyRootAdmin
        {
            require(0 < adminList.length, "empty admin list");
            uint256 index = adminList.length;
            while (0 < index) {
                --index;
                _adminMap[adminList[index]] = false;
            }
            emit RemoveAdminList(adminList);
        }
        /**
         * @notice Only root admin can call
         */
        function setRootAdmin(address rootAdminWallet) external onlyRootAdmin {
            _setRootAdmin(rootAdminWallet);
        }
        function _setRootAdmin(address wallet) private {
            require(wallet != address(0), "wallet is zero address");
            _rootAdmin = wallet;
            emit SetRootAdmin(wallet);
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity 0.8.19;
    import "./EIP712Domain.sol";
    import "./EIP712.sol";
    abstract contract EIP3009 is 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;
        mapping(address => mapping(bytes32 => bool)) internal _authorizationStates;
        event AuthorizationUsed(address indexed authorizer, bytes32 indexed nonce);
        error AuthorizationNotYetValid();
        error AuthorizationExpired();
        error NoncePreviouslyUsed();
        error InvalidSignature();
        function authorizationState(address authorizer, bytes32 nonce)
            external
            view
            returns (bool)
        {
            return _authorizationStates[authorizer][nonce];
        }
        function transferWithAuthorization(
            address from,
            address to,
            uint256 value,
            uint256 validAfter,
            uint256 validBefore,
            bytes32 nonce,
            uint8 v,
            bytes32 r,
            bytes32 s
        ) internal {
            if(block.timestamp <= validAfter)
                revert AuthorizationNotYetValid();
            if(block.timestamp >= validBefore)
                revert AuthorizationExpired();
            if(_authorizationStates[from][nonce])
                revert NoncePreviouslyUsed();
            bytes memory data = abi.encode(
                TRANSFER_WITH_AUTHORIZATION_TYPEHASH,
                from,
                to,
                value,
                validAfter,
                validBefore,
                nonce
            );
            if(EIP712.recover(DOMAIN_SEPARATOR, v, r, s, data) != from)
                revert InvalidSignature();
            _authorizationStates[from][nonce] = true;
            emit AuthorizationUsed(from, nonce);
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity 0.8.19;
    library EIP712 {
        // keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)")
        bytes32 public constant EIP712_DOMAIN_TYPEHASH =
            0x8b73c3c69bb8fe3d512ecc4cf759cc79239f7b179b0ffacaa9a75d522b39400f;
        function makeDomainSeparator(string memory name, string memory version)
            internal
            view
            returns (bytes32)
        {
            uint256 chainId;
            assembly {
                chainId := chainid()
            }
            return
                keccak256(
                    abi.encode(
                        EIP712_DOMAIN_TYPEHASH,
                        keccak256(bytes(name)),
                        keccak256(bytes(version)),
                        address(this),
                        bytes32(chainId)
                    )
                );
        }
        function recover(
            bytes32 domainSeparator,
            uint8 v,
            bytes32 r,
            bytes32 s,
            bytes memory typeHashAndData
        ) internal pure returns (address) {
            bytes32 digest = keccak256(
                abi.encodePacked(
                    "\\x19\\x01",
                    domainSeparator,
                    keccak256(typeHashAndData)
                )
            );
            address recovered = ecrecover(digest, v, r, s);
            require(recovered != address(0), "EIP712: invalid signature");
            return recovered;
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity 0.8.19;
    abstract contract EIP712Domain {
        bytes32 public DOMAIN_SEPARATOR;
    }
    // SPDX-License-Identifier: MIT
    pragma solidity 0.8.19;
    interface IPlatformToken {
        function specialTransferFrom(
            address from,
            uint256 value,
            uint256 validAfter,
            uint256 validBefore,
            bytes32 nonce,
            uint8 v,
            bytes32 r,
            bytes32 s
        ) external;
    }
    // SPDX-License-Identifier: MIT
    pragma solidity 0.8.19;
    import '@openzeppelin/contracts/utils/Address.sol';
    import '@openzeppelin/contracts/token/ERC20/ERC20.sol';
    import '@openzeppelin/contracts/token/ERC20/IERC20.sol';
    import '../access_controller/PlatformAccessController.sol';
    import './price_provider/IPlatformTokenPriceProvider.sol';
    import './EIP3009/EIP3009.sol';
    import {ReentrancyGuard} from "@openzeppelin/contracts/security/ReentrancyGuard.sol";
    import '@openzeppelin/contracts-upgradeable/token/ERC20/utils/SafeERC20Upgradeable.sol';
    import "./IplatformToken/IPlatformToken.sol";
    interface IAntisnipe {
        function assureCanTransfer(
            address sender,
            address from,
            address to,
            uint256 amount
        ) external;
    }
    /**
     * @notice ERC20 token with some extra functionality
     * By default, there are restrictions on transfers to contracts not in whitelist
     * Method for transferring without approval, you can see the contracts that use it
     */
    contract PlatformToken is ERC20, PlatformAccessController, EIP3009, ReentrancyGuard, IPlatformToken {
        using SafeERC20Upgradeable for IERC20;
        address private _vesting;
        address private _staking;
        IAntisnipe public antisnipe;
        bool public antisnipeDisable;
        event UpdateVesting(
            address _address,
            uint256 timestamp
        );
        event UpdateStaking(
            address _address,
            uint256 timestamp
        );
        event disableAntisnipe(
            uint256 timestamp
        );
        event UpdateAntisnipe(
            address _address,
            uint256 timestamp
        );
        error InvalidAddress();
        error ZeroAmount();
        error InvalidSender();
        error AntisnipeDisabled();
        /**
         * @param adminPanel platform admin panel address
         */
        constructor(
            address adminPanel,
            address recipient,
            uint256 supply
        ) ERC20('Propchain Token', 'PROPC') {
            if(adminPanel == address(0) || recipient == address(0))
                revert InvalidAddress();
            if(supply == 0)
                revert ZeroAmount();
            _initiatePlatformAccessController(adminPanel);
            _mint(recipient, supply);
        }
        /**
         * @notice Removed the initiate function as recommended and created various setters
         */
        function updateVestingAddress(address vesting) external onlyPlatformAdmin {
            if(vesting == address(0))
                revert InvalidAddress();
            _vesting = vesting;
            emit UpdateVesting(vesting, block.timestamp);
        }
        function updateStakingAddress(address staking) external onlyPlatformAdmin {
            if(staking == address(0))
                revert InvalidAddress();
            _staking = staking;
            emit UpdateStaking(staking, block.timestamp);
        }
        /**
         * @notice Burn tokens from the sender balance
         * Only platform admin can do
         */
        function burn(uint256 amount) external onlyPlatformAdmin {
            _burn(msgSender(), amount);
        }
        /**
         * @dev Similar to transferFrom, but to address is sender
         * Only vesting, staking and cashback contracts can call
         * Designed to save money, transfers without approval
         */
        function specialTransferFrom(
            address from,
            uint256 value,
            uint256 validAfter,
            uint256 validBefore,
            bytes32 nonce,
            uint8 v,
            bytes32 r,
            bytes32 s
        ) external nonReentrant {
            address to = msgSender();
            if(to != _vesting && to != _staking)
                revert InvalidSender();
            if(value == 0)
                revert ZeroAmount();
            transferWithAuthorization(
                from,
                to,
                value,
                validAfter,
                validBefore,
                nonce,
                v,
                r,
                s
            );
            _transfer(from, to, value);
        }
        /**
         * @dev Call before transfer
         * @param to address to tokens are transferring
         */
        function _beforeTokenTransfer(
            address from,
            address to,
            uint256 amount
        ) internal virtual override {
            if (from == address(0) || to == address(0)) return;
            if (!antisnipeDisable && address(antisnipe) != address(0))
                antisnipe.assureCanTransfer(msg.sender, from, to, amount);
        }
        function setAntisnipeDisable() external onlyPlatformAdmin {
            if(antisnipeDisable)
                revert AntisnipeDisabled();
            antisnipeDisable = true;
            emit disableAntisnipe(block.timestamp);
        }
        function setAntisnipeAddress(address addr) external onlyPlatformAdmin {
            if(addr == address(0))
                revert InvalidAddress();
            antisnipe = IAntisnipe(addr);
            emit UpdateAntisnipe(addr, block.timestamp);
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity 0.8.19;
    /**
     * @title Interface from which all implementations of pricing should inherit
     */
    interface IPlatformTokenPriceProvider {
        /**
         * @notice Returns the cost of the entered number of PROPC in USD
         * @param prop number of PROP (1 PROP == 10^18)
         * @return usdAmount number of USD (1 USD == 10^18)
         */
        function usdAmount(uint256 prop) external view returns (uint256);
        /**
         * @notice Returns the cost of the entered number of USD in PROP
         * @param usd number of USD (1 USD == 10^18)
         * @return tokenAmount number of PROP (1 PROP == 10^18)
         */
        function tokenAmount(uint256 usd) external view returns (uint256);
    }