ETH Price: $1,804.50 (-0.46%)
Gas: 0.38 Gwei

Transaction Decoder

Block:
21301751 at Nov-30-2024 04:41:23 PM +UTC
Transaction Fee:
0.00106048674363978 ETH $1.91
Gas Used:
64,620 Gas / 16.411122619 Gwei

Emitted Events:

Account State Difference:

  Address   Before After State Difference Code
(Titan Builder)
5.488031648506322118 Eth5.488105143959219298 Eth0.00007349545289718
0x5683F934...E714faDdE
0.008062250409461216 Eth
Nonce: 15
0.007001763665821436 Eth
Nonce: 16
0.00106048674363978
0xdAC17F95...13D831ec7

Execution Trace

FlaryTokenSale.withdrawUSDT( _amount=30000 )
  • TetherToken.approve( _spender=0x1ea9Bcd9C7483c9570057921459F4A64aFf39b0d, _value=30000 )
  • TetherToken.transferFrom( _from=0x1ea9Bcd9C7483c9570057921459F4A64aFf39b0d, _to=0x5683F934c30c7AE6345926A83eD0be0E714faDdE, _value=30000 )
    File 1 of 2: FlaryTokenSale
    // SPDX-License-Identifier: MIT
    pragma solidity 0.8.22;
    import {Ownable} from "@openzeppelin/contracts/access/Ownable.sol";
    import {Pausable} from "@openzeppelin/contracts/utils/Pausable.sol";
    import {ReentrancyGuard} from "@openzeppelin/contracts/utils/ReentrancyGuard.sol";
    import {ERC20} from "@openzeppelin/contracts/token/ERC20/ERC20.sol";
    import {SafeERC20} from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
    import {AggregatorV3Interface} from "@chainlink/contracts/src/v0.8/interfaces/AggregatorV3Interface.sol";
    contract FlaryTokenSale is Ownable, Pausable, ReentrancyGuard {
        using SafeERC20 for ERC20;
        ERC20 public usdt;
        AggregatorV3Interface public nativeUsdPriceFeed;
        uint256 public tokensPriceInUsdt;
        uint256 public tokenSold;
        mapping(address => uint256) public investemetByAddress;
        address[] public buyers;
        constructor(
            address _usdt,
            address _priceFeed,
            uint256 _tokensPriceInUsdt
        ) Ownable(msg.sender) {
            usdt = ERC20(_usdt);
            nativeUsdPriceFeed = AggregatorV3Interface(_priceFeed);
            tokensPriceInUsdt = _tokensPriceInUsdt;
        }
        function buyTokensNative() external payable whenNotPaused {
            buyers.push(msg.sender);
            (, int256 nativePrice, , , ) = nativeUsdPriceFeed.latestRoundData();
            uint8 feed_Decimals = nativeUsdPriceFeed.decimals();
            uint8 usdtDecimals = usdt.decimals();
            // assuming token's decimals 18
            uint256 tokensAmount;
            if (feed_Decimals > usdtDecimals) {
                tokensAmount =
                    (msg.value * uint256(nativePrice)) /
                    (tokensPriceInUsdt * 10 ** (feed_Decimals - usdtDecimals));
            } else {
                tokensAmount =
                    (msg.value *
                        uint256(nativePrice) *
                        10 ** (usdtDecimals - feed_Decimals)) /
                    tokensPriceInUsdt;
            }
            investemetByAddress[msg.sender] += tokensAmount;
            tokenSold += tokensAmount;
        }
        function buyTokensUSDT(uint256 amount) external whenNotPaused {
            usdt.safeTransferFrom(msg.sender, address(this), amount);
            uint256 tokensAmount = (amount * 10 ** 18) / tokensPriceInUsdt;
            investemetByAddress[msg.sender] += tokensAmount;
            tokenSold += tokensAmount;
        }
        function pause() external whenNotPaused onlyOwner {
            _pause();
        }
        function unpause() external whenPaused onlyOwner {
            _unpause();
        }
        function withdrawUSDT(uint256 _amount) external onlyOwner {
            usdt.forceApprove(address(this), _amount);
            usdt.safeTransferFrom(address(this), owner(), _amount);
        }
        function withdrawNative(uint256 _amount) external onlyOwner {
            (bool hs, ) = payable(owner()).call{value: _amount}("");
            require(hs, "EnergiWanBridge:: Failed to withdraw native coins");
        }
        function changePrice(uint256 _tokensPriceInUsdt) external onlyOwner {
            tokensPriceInUsdt = _tokensPriceInUsdt;
        }
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v5.0.0) (access/Ownable.sol)
    pragma solidity ^0.8.20;
    import {Context} from "../utils/Context.sol";
    /**
     * @dev Contract module which provides a basic access control mechanism, where
     * there is an account (an owner) that can be granted exclusive access to
     * specific functions.
     *
     * The initial owner is set to the address provided by the deployer. This can
     * later be changed with {transferOwnership}.
     *
     * This module is used through inheritance. It will make available the modifier
     * `onlyOwner`, which can be applied to your functions to restrict their use to
     * the owner.
     */
    abstract contract Ownable is Context {
        address private _owner;
        /**
         * @dev The caller account is not authorized to perform an operation.
         */
        error OwnableUnauthorizedAccount(address account);
        /**
         * @dev The owner is not a valid owner account. (eg. `address(0)`)
         */
        error OwnableInvalidOwner(address owner);
        event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
        /**
         * @dev Initializes the contract setting the address provided by the deployer as the initial owner.
         */
        constructor(address initialOwner) {
            if (initialOwner == address(0)) {
                revert OwnableInvalidOwner(address(0));
            }
            _transferOwnership(initialOwner);
        }
        /**
         * @dev Throws if called by any account other than the owner.
         */
        modifier onlyOwner() {
            _checkOwner();
            _;
        }
        /**
         * @dev Returns the address of the current owner.
         */
        function owner() public view virtual returns (address) {
            return _owner;
        }
        /**
         * @dev Throws if the sender is not the owner.
         */
        function _checkOwner() internal view virtual {
            if (owner() != _msgSender()) {
                revert OwnableUnauthorizedAccount(_msgSender());
            }
        }
        /**
         * @dev Leaves the contract without owner. It will not be possible to call
         * `onlyOwner` functions. Can only be called by the current owner.
         *
         * NOTE: Renouncing ownership will leave the contract without an owner,
         * thereby disabling any functionality that is only available to the owner.
         */
        function renounceOwnership() public virtual onlyOwner {
            _transferOwnership(address(0));
        }
        /**
         * @dev Transfers ownership of the contract to a new account (`newOwner`).
         * Can only be called by the current owner.
         */
        function transferOwnership(address newOwner) public virtual onlyOwner {
            if (newOwner == address(0)) {
                revert OwnableInvalidOwner(address(0));
            }
            _transferOwnership(newOwner);
        }
        /**
         * @dev Transfers ownership of the contract to a new account (`newOwner`).
         * Internal function without access restriction.
         */
        function _transferOwnership(address newOwner) internal virtual {
            address oldOwner = _owner;
            _owner = newOwner;
            emit OwnershipTransferred(oldOwner, newOwner);
        }
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v5.0.0) (utils/Pausable.sol)
    pragma solidity ^0.8.20;
    import {Context} from "../utils/Context.sol";
    /**
     * @dev Contract module which allows children to implement an emergency stop
     * mechanism that can be triggered by an authorized account.
     *
     * This module is used through inheritance. It will make available the
     * modifiers `whenNotPaused` and `whenPaused`, which can be applied to
     * the functions of your contract. Note that they will not be pausable by
     * simply including this module, only once the modifiers are put in place.
     */
    abstract contract Pausable is Context {
        bool private _paused;
        /**
         * @dev Emitted when the pause is triggered by `account`.
         */
        event Paused(address account);
        /**
         * @dev Emitted when the pause is lifted by `account`.
         */
        event Unpaused(address account);
        /**
         * @dev The operation failed because the contract is paused.
         */
        error EnforcedPause();
        /**
         * @dev The operation failed because the contract is not paused.
         */
        error ExpectedPause();
        /**
         * @dev Initializes the contract in unpaused state.
         */
        constructor() {
            _paused = false;
        }
        /**
         * @dev Modifier to make a function callable only when the contract is not paused.
         *
         * Requirements:
         *
         * - The contract must not be paused.
         */
        modifier whenNotPaused() {
            _requireNotPaused();
            _;
        }
        /**
         * @dev Modifier to make a function callable only when the contract is paused.
         *
         * Requirements:
         *
         * - The contract must be paused.
         */
        modifier whenPaused() {
            _requirePaused();
            _;
        }
        /**
         * @dev Returns true if the contract is paused, and false otherwise.
         */
        function paused() public view virtual returns (bool) {
            return _paused;
        }
        /**
         * @dev Throws if the contract is paused.
         */
        function _requireNotPaused() internal view virtual {
            if (paused()) {
                revert EnforcedPause();
            }
        }
        /**
         * @dev Throws if the contract is not paused.
         */
        function _requirePaused() internal view virtual {
            if (!paused()) {
                revert ExpectedPause();
            }
        }
        /**
         * @dev Triggers stopped state.
         *
         * Requirements:
         *
         * - The contract must not be paused.
         */
        function _pause() internal virtual whenNotPaused {
            _paused = true;
            emit Paused(_msgSender());
        }
        /**
         * @dev Returns to normal state.
         *
         * Requirements:
         *
         * - The contract must be paused.
         */
        function _unpause() internal virtual whenPaused {
            _paused = false;
            emit Unpaused(_msgSender());
        }
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v5.0.0) (utils/ReentrancyGuard.sol)
    pragma solidity ^0.8.20;
    /**
     * @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;
        /**
         * @dev Unauthorized reentrant call.
         */
        error ReentrancyGuardReentrantCall();
        constructor() {
            _status = NOT_ENTERED;
        }
        /**
         * @dev Prevents a contract from calling itself, directly or indirectly.
         * Calling a `nonReentrant` function from another `nonReentrant`
         * function is not supported. It is possible to prevent this from happening
         * by making the `nonReentrant` function external, and making it call a
         * `private` function that does the actual work.
         */
        modifier nonReentrant() {
            _nonReentrantBefore();
            _;
            _nonReentrantAfter();
        }
        function _nonReentrantBefore() private {
            // On the first call to nonReentrant, _status will be NOT_ENTERED
            if (_status == ENTERED) {
                revert ReentrancyGuardReentrantCall();
            }
            // Any calls to nonReentrant after this point will fail
            _status = ENTERED;
        }
        function _nonReentrantAfter() private {
            // By storing the original value once again, a refund is triggered (see
            // https://eips.ethereum.org/EIPS/eip-2200)
            _status = NOT_ENTERED;
        }
        /**
         * @dev Returns true if the reentrancy guard is currently set to "entered", which indicates there is a
         * `nonReentrant` function in the call stack.
         */
        function _reentrancyGuardEntered() internal view returns (bool) {
            return _status == ENTERED;
        }
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v5.0.0) (token/ERC20/ERC20.sol)
    pragma solidity ^0.8.20;
    import {IERC20} from "./IERC20.sol";
    import {IERC20Metadata} from "./extensions/IERC20Metadata.sol";
    import {Context} from "../../utils/Context.sol";
    import {IERC20Errors} from "../../interfaces/draft-IERC6093.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}.
     *
     * TIP: For a detailed writeup see our guide
     * https://forum.openzeppelin.com/t/how-to-implement-erc20-supply-mechanisms/226[How
     * to implement supply mechanisms].
     *
     * The default value of {decimals} is 18. To change this, you should override
     * this function so it returns a different value.
     *
     * We have followed general OpenZeppelin Contracts guidelines: functions revert
     * instead returning `false` on failure. This behavior is nonetheless
     * conventional and does not conflict with the expectations of ERC20
     * applications.
     *
     * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
     * This allows applications to reconstruct the allowance for all accounts just
     * by listening to said events. Other implementations of the EIP may not emit
     * these events, as it isn't required by the specification.
     */
    abstract contract ERC20 is Context, IERC20, IERC20Metadata, IERC20Errors {
        mapping(address account => uint256) private _balances;
        mapping(address account => mapping(address spender => uint256)) private _allowances;
        uint256 private _totalSupply;
        string private _name;
        string private _symbol;
        /**
         * @dev Sets the values for {name} and {symbol}.
         *
         * All two of these values are immutable: they can only be set once during
         * construction.
         */
        constructor(string memory name_, string memory symbol_) {
            _name = name_;
            _symbol = symbol_;
        }
        /**
         * @dev Returns the name of the token.
         */
        function name() public view virtual returns (string memory) {
            return _name;
        }
        /**
         * @dev Returns the symbol of the token, usually a shorter version of the
         * name.
         */
        function symbol() public view virtual returns (string memory) {
            return _symbol;
        }
        /**
         * @dev Returns the number of decimals used to get its user representation.
         * For example, if `decimals` equals `2`, a balance of `505` tokens should
         * be displayed to a user as `5.05` (`505 / 10 ** 2`).
         *
         * Tokens usually opt for a value of 18, imitating the relationship between
         * Ether and Wei. This is the default value returned by this function, unless
         * it's overridden.
         *
         * NOTE: This information is only used for _display_ purposes: it in
         * no way affects any of the arithmetic of the contract, including
         * {IERC20-balanceOf} and {IERC20-transfer}.
         */
        function decimals() public view virtual returns (uint8) {
            return 18;
        }
        /**
         * @dev See {IERC20-totalSupply}.
         */
        function totalSupply() public view virtual returns (uint256) {
            return _totalSupply;
        }
        /**
         * @dev See {IERC20-balanceOf}.
         */
        function balanceOf(address account) public view virtual 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 `value`.
         */
        function transfer(address to, uint256 value) public virtual returns (bool) {
            address owner = _msgSender();
            _transfer(owner, to, value);
            return true;
        }
        /**
         * @dev See {IERC20-allowance}.
         */
        function allowance(address owner, address spender) public view virtual returns (uint256) {
            return _allowances[owner][spender];
        }
        /**
         * @dev See {IERC20-approve}.
         *
         * NOTE: If `value` 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 value) public virtual returns (bool) {
            address owner = _msgSender();
            _approve(owner, spender, value);
            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 `value`.
         * - the caller must have allowance for ``from``'s tokens of at least
         * `value`.
         */
        function transferFrom(address from, address to, uint256 value) public virtual returns (bool) {
            address spender = _msgSender();
            _spendAllowance(from, spender, value);
            _transfer(from, to, value);
            return true;
        }
        /**
         * @dev Moves a `value` 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.
         *
         * NOTE: This function is not virtual, {_update} should be overridden instead.
         */
        function _transfer(address from, address to, uint256 value) internal {
            if (from == address(0)) {
                revert ERC20InvalidSender(address(0));
            }
            if (to == address(0)) {
                revert ERC20InvalidReceiver(address(0));
            }
            _update(from, to, value);
        }
        /**
         * @dev Transfers a `value` amount of tokens from `from` to `to`, or alternatively mints (or burns) if `from`
         * (or `to`) is the zero address. All customizations to transfers, mints, and burns should be done by overriding
         * this function.
         *
         * Emits a {Transfer} event.
         */
        function _update(address from, address to, uint256 value) internal virtual {
            if (from == address(0)) {
                // Overflow check required: The rest of the code assumes that totalSupply never overflows
                _totalSupply += value;
            } else {
                uint256 fromBalance = _balances[from];
                if (fromBalance < value) {
                    revert ERC20InsufficientBalance(from, fromBalance, value);
                }
                unchecked {
                    // Overflow not possible: value <= fromBalance <= totalSupply.
                    _balances[from] = fromBalance - value;
                }
            }
            if (to == address(0)) {
                unchecked {
                    // Overflow not possible: value <= totalSupply or value <= fromBalance <= totalSupply.
                    _totalSupply -= value;
                }
            } else {
                unchecked {
                    // Overflow not possible: balance + value is at most totalSupply, which we know fits into a uint256.
                    _balances[to] += value;
                }
            }
            emit Transfer(from, to, value);
        }
        /**
         * @dev Creates a `value` amount of tokens and assigns them to `account`, by transferring it from address(0).
         * Relies on the `_update` mechanism
         *
         * Emits a {Transfer} event with `from` set to the zero address.
         *
         * NOTE: This function is not virtual, {_update} should be overridden instead.
         */
        function _mint(address account, uint256 value) internal {
            if (account == address(0)) {
                revert ERC20InvalidReceiver(address(0));
            }
            _update(address(0), account, value);
        }
        /**
         * @dev Destroys a `value` amount of tokens from `account`, lowering the total supply.
         * Relies on the `_update` mechanism.
         *
         * Emits a {Transfer} event with `to` set to the zero address.
         *
         * NOTE: This function is not virtual, {_update} should be overridden instead
         */
        function _burn(address account, uint256 value) internal {
            if (account == address(0)) {
                revert ERC20InvalidSender(address(0));
            }
            _update(account, address(0), value);
        }
        /**
         * @dev Sets `value` 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.
         *
         * Overrides to this logic should be done to the variant with an additional `bool emitEvent` argument.
         */
        function _approve(address owner, address spender, uint256 value) internal {
            _approve(owner, spender, value, true);
        }
        /**
         * @dev Variant of {_approve} with an optional flag to enable or disable the {Approval} event.
         *
         * By default (when calling {_approve}) the flag is set to true. On the other hand, approval changes made by
         * `_spendAllowance` during the `transferFrom` operation set the flag to false. This saves gas by not emitting any
         * `Approval` event during `transferFrom` operations.
         *
         * Anyone who wishes to continue emitting `Approval` events on the`transferFrom` operation can force the flag to
         * true using the following override:
         * ```
         * function _approve(address owner, address spender, uint256 value, bool) internal virtual override {
         *     super._approve(owner, spender, value, true);
         * }
         * ```
         *
         * Requirements are the same as {_approve}.
         */
        function _approve(address owner, address spender, uint256 value, bool emitEvent) internal virtual {
            if (owner == address(0)) {
                revert ERC20InvalidApprover(address(0));
            }
            if (spender == address(0)) {
                revert ERC20InvalidSpender(address(0));
            }
            _allowances[owner][spender] = value;
            if (emitEvent) {
                emit Approval(owner, spender, value);
            }
        }
        /**
         * @dev Updates `owner` s allowance for `spender` based on spent `value`.
         *
         * Does not update the allowance value in case of infinite allowance.
         * Revert if not enough allowance is available.
         *
         * Does not emit an {Approval} event.
         */
        function _spendAllowance(address owner, address spender, uint256 value) internal virtual {
            uint256 currentAllowance = allowance(owner, spender);
            if (currentAllowance != type(uint256).max) {
                if (currentAllowance < value) {
                    revert ERC20InsufficientAllowance(spender, currentAllowance, value);
                }
                unchecked {
                    _approve(owner, spender, currentAllowance - value, false);
                }
            }
        }
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v5.0.0) (token/ERC20/utils/SafeERC20.sol)
    pragma solidity ^0.8.20;
    import {IERC20} from "../IERC20.sol";
    import {IERC20Permit} from "../extensions/IERC20Permit.sol";
    import {Address} from "../../../utils/Address.sol";
    /**
     * @title SafeERC20
     * @dev Wrappers around ERC20 operations that throw on failure (when the token
     * contract returns false). Tokens that return no value (and instead revert or
     * throw on failure) are also supported, non-reverting calls are assumed to be
     * successful.
     * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
     * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
     */
    library SafeERC20 {
        using Address for address;
        /**
         * @dev An operation with an ERC20 token failed.
         */
        error SafeERC20FailedOperation(address token);
        /**
         * @dev Indicates a failed `decreaseAllowance` request.
         */
        error SafeERC20FailedDecreaseAllowance(address spender, uint256 currentAllowance, uint256 requestedDecrease);
        /**
         * @dev Transfer `value` amount of `token` from the calling contract to `to`. If `token` returns no value,
         * non-reverting calls are assumed to be successful.
         */
        function safeTransfer(IERC20 token, address to, uint256 value) internal {
            _callOptionalReturn(token, abi.encodeCall(token.transfer, (to, value)));
        }
        /**
         * @dev Transfer `value` amount of `token` from `from` to `to`, spending the approval given by `from` to the
         * calling contract. If `token` returns no value, non-reverting calls are assumed to be successful.
         */
        function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
            _callOptionalReturn(token, abi.encodeCall(token.transferFrom, (from, to, value)));
        }
        /**
         * @dev Increase the calling contract's allowance toward `spender` by `value`. If `token` returns no value,
         * non-reverting calls are assumed to be successful.
         */
        function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
            uint256 oldAllowance = token.allowance(address(this), spender);
            forceApprove(token, spender, oldAllowance + value);
        }
        /**
         * @dev Decrease the calling contract's allowance toward `spender` by `requestedDecrease`. If `token` returns no
         * value, non-reverting calls are assumed to be successful.
         */
        function safeDecreaseAllowance(IERC20 token, address spender, uint256 requestedDecrease) internal {
            unchecked {
                uint256 currentAllowance = token.allowance(address(this), spender);
                if (currentAllowance < requestedDecrease) {
                    revert SafeERC20FailedDecreaseAllowance(spender, currentAllowance, requestedDecrease);
                }
                forceApprove(token, spender, currentAllowance - requestedDecrease);
            }
        }
        /**
         * @dev Set the calling contract's allowance toward `spender` to `value`. If `token` returns no value,
         * non-reverting calls are assumed to be successful. Meant to be used with tokens that require the approval
         * to be set to zero before setting it to a non-zero value, such as USDT.
         */
        function forceApprove(IERC20 token, address spender, uint256 value) internal {
            bytes memory approvalCall = abi.encodeCall(token.approve, (spender, value));
            if (!_callOptionalReturnBool(token, approvalCall)) {
                _callOptionalReturn(token, abi.encodeCall(token.approve, (spender, 0)));
                _callOptionalReturn(token, approvalCall);
            }
        }
        /**
         * @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);
            if (returndata.length != 0 && !abi.decode(returndata, (bool))) {
                revert SafeERC20FailedOperation(address(token));
            }
        }
        /**
         * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
         * on the return value: the return value is optional (but if data is returned, it must not be false).
         * @param token The token targeted by the call.
         * @param data The call data (encoded using abi.encode or one of its variants).
         *
         * This is a variant of {_callOptionalReturn} that silents catches all reverts and returns a bool instead.
         */
        function _callOptionalReturnBool(IERC20 token, bytes memory data) private returns (bool) {
            // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
            // we're implementing it ourselves. We cannot use {Address-functionCall} here since this should return false
            // and not revert is the subcall reverts.
            (bool success, bytes memory returndata) = address(token).call(data);
            return success && (returndata.length == 0 || abi.decode(returndata, (bool))) && address(token).code.length > 0;
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    interface AggregatorV3Interface {
      function decimals() external view returns (uint8);
      function description() external view returns (string memory);
      function version() external view returns (uint256);
      function getRoundData(
        uint80 _roundId
      ) external view returns (uint80 roundId, int256 answer, uint256 startedAt, uint256 updatedAt, uint80 answeredInRound);
      function latestRoundData()
        external
        view
        returns (uint80 roundId, int256 answer, uint256 startedAt, uint256 updatedAt, uint80 answeredInRound);
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v5.0.1) (utils/Context.sol)
    pragma solidity ^0.8.20;
    /**
     * @dev Provides information about the current execution context, including the
     * sender of the transaction and its data. While these are generally available
     * via msg.sender and msg.data, they should not be accessed in such a direct
     * manner, since when dealing with meta-transactions the account sending and
     * paying for execution may not be the actual sender (as far as an application
     * is concerned).
     *
     * This contract is only required for intermediate, library-like contracts.
     */
    abstract contract Context {
        function _msgSender() internal view virtual returns (address) {
            return msg.sender;
        }
        function _msgData() internal view virtual returns (bytes calldata) {
            return msg.data;
        }
        function _contextSuffixLength() internal view virtual returns (uint256) {
            return 0;
        }
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v5.0.0) (token/ERC20/IERC20.sol)
    pragma solidity ^0.8.20;
    /**
     * @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 value of tokens in existence.
         */
        function totalSupply() external view returns (uint256);
        /**
         * @dev Returns the value of tokens owned by `account`.
         */
        function balanceOf(address account) external view returns (uint256);
        /**
         * @dev Moves a `value` amount of 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 value) 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 a `value` amount of tokens 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 value) external returns (bool);
        /**
         * @dev Moves a `value` amount of tokens from `from` to `to` using the
         * allowance mechanism. `value` 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 value) external returns (bool);
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v5.0.0) (token/ERC20/extensions/IERC20Metadata.sol)
    pragma solidity ^0.8.20;
    import {IERC20} from "../IERC20.sol";
    /**
     * @dev Interface for the optional metadata functions from the ERC20 standard.
     */
    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 v5.0.0) (interfaces/draft-IERC6093.sol)
    pragma solidity ^0.8.20;
    /**
     * @dev Standard ERC20 Errors
     * Interface of the https://eips.ethereum.org/EIPS/eip-6093[ERC-6093] custom errors for ERC20 tokens.
     */
    interface IERC20Errors {
        /**
         * @dev Indicates an error related to the current `balance` of a `sender`. Used in transfers.
         * @param sender Address whose tokens are being transferred.
         * @param balance Current balance for the interacting account.
         * @param needed Minimum amount required to perform a transfer.
         */
        error ERC20InsufficientBalance(address sender, uint256 balance, uint256 needed);
        /**
         * @dev Indicates a failure with the token `sender`. Used in transfers.
         * @param sender Address whose tokens are being transferred.
         */
        error ERC20InvalidSender(address sender);
        /**
         * @dev Indicates a failure with the token `receiver`. Used in transfers.
         * @param receiver Address to which tokens are being transferred.
         */
        error ERC20InvalidReceiver(address receiver);
        /**
         * @dev Indicates a failure with the `spender`’s `allowance`. Used in transfers.
         * @param spender Address that may be allowed to operate on tokens without being their owner.
         * @param allowance Amount of tokens a `spender` is allowed to operate with.
         * @param needed Minimum amount required to perform a transfer.
         */
        error ERC20InsufficientAllowance(address spender, uint256 allowance, uint256 needed);
        /**
         * @dev Indicates a failure with the `approver` of a token to be approved. Used in approvals.
         * @param approver Address initiating an approval operation.
         */
        error ERC20InvalidApprover(address approver);
        /**
         * @dev Indicates a failure with the `spender` to be approved. Used in approvals.
         * @param spender Address that may be allowed to operate on tokens without being their owner.
         */
        error ERC20InvalidSpender(address spender);
    }
    /**
     * @dev Standard ERC721 Errors
     * Interface of the https://eips.ethereum.org/EIPS/eip-6093[ERC-6093] custom errors for ERC721 tokens.
     */
    interface IERC721Errors {
        /**
         * @dev Indicates that an address can't be an owner. For example, `address(0)` is a forbidden owner in EIP-20.
         * Used in balance queries.
         * @param owner Address of the current owner of a token.
         */
        error ERC721InvalidOwner(address owner);
        /**
         * @dev Indicates a `tokenId` whose `owner` is the zero address.
         * @param tokenId Identifier number of a token.
         */
        error ERC721NonexistentToken(uint256 tokenId);
        /**
         * @dev Indicates an error related to the ownership over a particular token. Used in transfers.
         * @param sender Address whose tokens are being transferred.
         * @param tokenId Identifier number of a token.
         * @param owner Address of the current owner of a token.
         */
        error ERC721IncorrectOwner(address sender, uint256 tokenId, address owner);
        /**
         * @dev Indicates a failure with the token `sender`. Used in transfers.
         * @param sender Address whose tokens are being transferred.
         */
        error ERC721InvalidSender(address sender);
        /**
         * @dev Indicates a failure with the token `receiver`. Used in transfers.
         * @param receiver Address to which tokens are being transferred.
         */
        error ERC721InvalidReceiver(address receiver);
        /**
         * @dev Indicates a failure with the `operator`’s approval. Used in transfers.
         * @param operator Address that may be allowed to operate on tokens without being their owner.
         * @param tokenId Identifier number of a token.
         */
        error ERC721InsufficientApproval(address operator, uint256 tokenId);
        /**
         * @dev Indicates a failure with the `approver` of a token to be approved. Used in approvals.
         * @param approver Address initiating an approval operation.
         */
        error ERC721InvalidApprover(address approver);
        /**
         * @dev Indicates a failure with the `operator` to be approved. Used in approvals.
         * @param operator Address that may be allowed to operate on tokens without being their owner.
         */
        error ERC721InvalidOperator(address operator);
    }
    /**
     * @dev Standard ERC1155 Errors
     * Interface of the https://eips.ethereum.org/EIPS/eip-6093[ERC-6093] custom errors for ERC1155 tokens.
     */
    interface IERC1155Errors {
        /**
         * @dev Indicates an error related to the current `balance` of a `sender`. Used in transfers.
         * @param sender Address whose tokens are being transferred.
         * @param balance Current balance for the interacting account.
         * @param needed Minimum amount required to perform a transfer.
         * @param tokenId Identifier number of a token.
         */
        error ERC1155InsufficientBalance(address sender, uint256 balance, uint256 needed, uint256 tokenId);
        /**
         * @dev Indicates a failure with the token `sender`. Used in transfers.
         * @param sender Address whose tokens are being transferred.
         */
        error ERC1155InvalidSender(address sender);
        /**
         * @dev Indicates a failure with the token `receiver`. Used in transfers.
         * @param receiver Address to which tokens are being transferred.
         */
        error ERC1155InvalidReceiver(address receiver);
        /**
         * @dev Indicates a failure with the `operator`’s approval. Used in transfers.
         * @param operator Address that may be allowed to operate on tokens without being their owner.
         * @param owner Address of the current owner of a token.
         */
        error ERC1155MissingApprovalForAll(address operator, address owner);
        /**
         * @dev Indicates a failure with the `approver` of a token to be approved. Used in approvals.
         * @param approver Address initiating an approval operation.
         */
        error ERC1155InvalidApprover(address approver);
        /**
         * @dev Indicates a failure with the `operator` to be approved. Used in approvals.
         * @param operator Address that may be allowed to operate on tokens without being their owner.
         */
        error ERC1155InvalidOperator(address operator);
        /**
         * @dev Indicates an array length mismatch between ids and values in a safeBatchTransferFrom operation.
         * Used in batch transfers.
         * @param idsLength Length of the array of token identifiers
         * @param valuesLength Length of the array of token amounts
         */
        error ERC1155InvalidArrayLength(uint256 idsLength, uint256 valuesLength);
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v5.0.0) (token/ERC20/extensions/IERC20Permit.sol)
    pragma solidity ^0.8.20;
    /**
     * @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
     * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
     *
     * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
     * presenting a message signed by the account. By not relying on {IERC20-approve}, the token holder account doesn't
     * need to send a transaction, and thus is not required to hold Ether at all.
     *
     * ==== Security Considerations
     *
     * There are two important considerations concerning the use of `permit`. The first is that a valid permit signature
     * expresses an allowance, and it should not be assumed to convey additional meaning. In particular, it should not be
     * considered as an intention to spend the allowance in any specific way. The second is that because permits have
     * built-in replay protection and can be submitted by anyone, they can be frontrun. A protocol that uses permits should
     * take this into consideration and allow a `permit` call to fail. Combining these two aspects, a pattern that may be
     * generally recommended is:
     *
     * ```solidity
     * function doThingWithPermit(..., uint256 value, uint256 deadline, uint8 v, bytes32 r, bytes32 s) public {
     *     try token.permit(msg.sender, address(this), value, deadline, v, r, s) {} catch {}
     *     doThing(..., value);
     * }
     *
     * function doThing(..., uint256 value) public {
     *     token.safeTransferFrom(msg.sender, address(this), value);
     *     ...
     * }
     * ```
     *
     * Observe that: 1) `msg.sender` is used as the owner, leaving no ambiguity as to the signer intent, and 2) the use of
     * `try/catch` allows the permit to fail and makes the code tolerant to frontrunning. (See also
     * {SafeERC20-safeTransferFrom}).
     *
     * Additionally, note that smart contract wallets (such as Argent or Safe) are not able to produce permit signatures, so
     * contracts should have entry points that don't rely on permit.
     */
    interface IERC20Permit {
        /**
         * @dev Sets `value` as the allowance of `spender` over ``owner``'s tokens,
         * given ``owner``'s signed approval.
         *
         * IMPORTANT: The same issues {IERC20-approve} has related to transaction
         * ordering also apply here.
         *
         * Emits an {Approval} event.
         *
         * Requirements:
         *
         * - `spender` cannot be the zero address.
         * - `deadline` must be a timestamp in the future.
         * - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner`
         * over the EIP712-formatted function arguments.
         * - the signature must use ``owner``'s current nonce (see {nonces}).
         *
         * For more information on the signature format, see the
         * https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP
         * section].
         *
         * CAUTION: See Security Considerations above.
         */
        function permit(
            address owner,
            address spender,
            uint256 value,
            uint256 deadline,
            uint8 v,
            bytes32 r,
            bytes32 s
        ) external;
        /**
         * @dev Returns the current nonce for `owner`. This value must be
         * included whenever a signature is generated for {permit}.
         *
         * Every successful call to {permit} increases ``owner``'s nonce by one. This
         * prevents a signature from being used multiple times.
         */
        function nonces(address owner) external view returns (uint256);
        /**
         * @dev Returns the domain separator used in the encoding of the signature for {permit}, as defined by {EIP712}.
         */
        // solhint-disable-next-line func-name-mixedcase
        function DOMAIN_SEPARATOR() external view returns (bytes32);
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v5.0.0) (utils/Address.sol)
    pragma solidity ^0.8.20;
    /**
     * @dev Collection of functions related to the address type
     */
    library Address {
        /**
         * @dev The ETH balance of the account is not enough to perform the operation.
         */
        error AddressInsufficientBalance(address account);
        /**
         * @dev There's no code at `target` (it is not a contract).
         */
        error AddressEmptyCode(address target);
        /**
         * @dev A call to an address target failed. The target may have reverted.
         */
        error FailedInnerCall();
        /**
         * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
         * `recipient`, forwarding all available gas and reverting on errors.
         *
         * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
         * of certain opcodes, possibly making contracts go over the 2300 gas limit
         * imposed by `transfer`, making them unable to receive funds via
         * `transfer`. {sendValue} removes this limitation.
         *
         * https://consensys.net/diligence/blog/2019/09/stop-using-soliditys-transfer-now/[Learn more].
         *
         * IMPORTANT: because control is transferred to `recipient`, care must be
         * taken to not create reentrancy vulnerabilities. Consider using
         * {ReentrancyGuard} or the
         * https://solidity.readthedocs.io/en/v0.8.20/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
         */
        function sendValue(address payable recipient, uint256 amount) internal {
            if (address(this).balance < amount) {
                revert AddressInsufficientBalance(address(this));
            }
            (bool success, ) = recipient.call{value: amount}("");
            if (!success) {
                revert FailedInnerCall();
            }
        }
        /**
         * @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 or custom error, it is bubbled
         * up by this function (like regular Solidity function calls). However, if
         * the call reverted with no returned reason, this function reverts with a
         * {FailedInnerCall} error.
         *
         * 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.
         */
        function functionCall(address target, bytes memory data) internal returns (bytes memory) {
            return functionCallWithValue(target, data, 0);
        }
        /**
         * @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`.
         */
        function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
            if (address(this).balance < value) {
                revert AddressInsufficientBalance(address(this));
            }
            (bool success, bytes memory returndata) = target.call{value: value}(data);
            return verifyCallResultFromTarget(target, success, returndata);
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
         * but performing a static call.
         */
        function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
            (bool success, bytes memory returndata) = target.staticcall(data);
            return verifyCallResultFromTarget(target, success, returndata);
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
         * but performing a delegate call.
         */
        function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
            (bool success, bytes memory returndata) = target.delegatecall(data);
            return verifyCallResultFromTarget(target, success, returndata);
        }
        /**
         * @dev Tool to verify that a low level call to smart-contract was successful, and reverts if the target
         * was not a contract or bubbling up the revert reason (falling back to {FailedInnerCall}) in case of an
         * unsuccessful call.
         */
        function verifyCallResultFromTarget(
            address target,
            bool success,
            bytes memory returndata
        ) internal view returns (bytes memory) {
            if (!success) {
                _revert(returndata);
            } else {
                // only check if target is a contract if the call was successful and the return data is empty
                // otherwise we already know that it was a contract
                if (returndata.length == 0 && target.code.length == 0) {
                    revert AddressEmptyCode(target);
                }
                return returndata;
            }
        }
        /**
         * @dev Tool to verify that a low level call was successful, and reverts if it wasn't, either by bubbling the
         * revert reason or with a default {FailedInnerCall} error.
         */
        function verifyCallResult(bool success, bytes memory returndata) internal pure returns (bytes memory) {
            if (!success) {
                _revert(returndata);
            } else {
                return returndata;
            }
        }
        /**
         * @dev Reverts with returndata if present. Otherwise reverts with {FailedInnerCall}.
         */
        function _revert(bytes memory returndata) 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 FailedInnerCall();
            }
        }
    }
    

    File 2 of 2: TetherToken
    pragma solidity ^0.4.17;
    
    /**
     * @title SafeMath
     * @dev Math operations with safety checks that throw on error
     */
    library SafeMath {
        function mul(uint256 a, uint256 b) internal pure returns (uint256) {
            if (a == 0) {
                return 0;
            }
            uint256 c = a * b;
            assert(c / a == b);
            return c;
        }
    
        function div(uint256 a, uint256 b) internal pure returns (uint256) {
            // assert(b > 0); // Solidity automatically throws when dividing by 0
            uint256 c = a / b;
            // assert(a == b * c + a % b); // There is no case in which this doesn't hold
            return c;
        }
    
        function sub(uint256 a, uint256 b) internal pure returns (uint256) {
            assert(b <= a);
            return a - b;
        }
    
        function add(uint256 a, uint256 b) internal pure returns (uint256) {
            uint256 c = a + b;
            assert(c >= a);
            return c;
        }
    }
    
    /**
     * @title Ownable
     * @dev The Ownable contract has an owner address, and provides basic authorization control
     * functions, this simplifies the implementation of "user permissions".
     */
    contract Ownable {
        address public owner;
    
        /**
          * @dev The Ownable constructor sets the original `owner` of the contract to the sender
          * account.
          */
        function Ownable() public {
            owner = msg.sender;
        }
    
        /**
          * @dev Throws if called by any account other than the owner.
          */
        modifier onlyOwner() {
            require(msg.sender == owner);
            _;
        }
    
        /**
        * @dev Allows the current owner to transfer control of the contract to a newOwner.
        * @param newOwner The address to transfer ownership to.
        */
        function transferOwnership(address newOwner) public onlyOwner {
            if (newOwner != address(0)) {
                owner = newOwner;
            }
        }
    
    }
    
    /**
     * @title ERC20Basic
     * @dev Simpler version of ERC20 interface
     * @dev see https://github.com/ethereum/EIPs/issues/20
     */
    contract ERC20Basic {
        uint public _totalSupply;
        function totalSupply() public constant returns (uint);
        function balanceOf(address who) public constant returns (uint);
        function transfer(address to, uint value) public;
        event Transfer(address indexed from, address indexed to, uint value);
    }
    
    /**
     * @title ERC20 interface
     * @dev see https://github.com/ethereum/EIPs/issues/20
     */
    contract ERC20 is ERC20Basic {
        function allowance(address owner, address spender) public constant returns (uint);
        function transferFrom(address from, address to, uint value) public;
        function approve(address spender, uint value) public;
        event Approval(address indexed owner, address indexed spender, uint value);
    }
    
    /**
     * @title Basic token
     * @dev Basic version of StandardToken, with no allowances.
     */
    contract BasicToken is Ownable, ERC20Basic {
        using SafeMath for uint;
    
        mapping(address => uint) public balances;
    
        // additional variables for use if transaction fees ever became necessary
        uint public basisPointsRate = 0;
        uint public maximumFee = 0;
    
        /**
        * @dev Fix for the ERC20 short address attack.
        */
        modifier onlyPayloadSize(uint size) {
            require(!(msg.data.length < size + 4));
            _;
        }
    
        /**
        * @dev transfer token for a specified address
        * @param _to The address to transfer to.
        * @param _value The amount to be transferred.
        */
        function transfer(address _to, uint _value) public onlyPayloadSize(2 * 32) {
            uint fee = (_value.mul(basisPointsRate)).div(10000);
            if (fee > maximumFee) {
                fee = maximumFee;
            }
            uint sendAmount = _value.sub(fee);
            balances[msg.sender] = balances[msg.sender].sub(_value);
            balances[_to] = balances[_to].add(sendAmount);
            if (fee > 0) {
                balances[owner] = balances[owner].add(fee);
                Transfer(msg.sender, owner, fee);
            }
            Transfer(msg.sender, _to, sendAmount);
        }
    
        /**
        * @dev Gets the balance of the specified address.
        * @param _owner The address to query the the balance of.
        * @return An uint representing the amount owned by the passed address.
        */
        function balanceOf(address _owner) public constant returns (uint balance) {
            return balances[_owner];
        }
    
    }
    
    /**
     * @title Standard ERC20 token
     *
     * @dev Implementation of the basic standard token.
     * @dev https://github.com/ethereum/EIPs/issues/20
     * @dev Based oncode by FirstBlood: https://github.com/Firstbloodio/token/blob/master/smart_contract/FirstBloodToken.sol
     */
    contract StandardToken is BasicToken, ERC20 {
    
        mapping (address => mapping (address => uint)) public allowed;
    
        uint public constant MAX_UINT = 2**256 - 1;
    
        /**
        * @dev Transfer tokens from one address to another
        * @param _from address The address which you want to send tokens from
        * @param _to address The address which you want to transfer to
        * @param _value uint the amount of tokens to be transferred
        */
        function transferFrom(address _from, address _to, uint _value) public onlyPayloadSize(3 * 32) {
            var _allowance = allowed[_from][msg.sender];
    
            // Check is not needed because sub(_allowance, _value) will already throw if this condition is not met
            // if (_value > _allowance) throw;
    
            uint fee = (_value.mul(basisPointsRate)).div(10000);
            if (fee > maximumFee) {
                fee = maximumFee;
            }
            if (_allowance < MAX_UINT) {
                allowed[_from][msg.sender] = _allowance.sub(_value);
            }
            uint sendAmount = _value.sub(fee);
            balances[_from] = balances[_from].sub(_value);
            balances[_to] = balances[_to].add(sendAmount);
            if (fee > 0) {
                balances[owner] = balances[owner].add(fee);
                Transfer(_from, owner, fee);
            }
            Transfer(_from, _to, sendAmount);
        }
    
        /**
        * @dev Approve the passed address to spend the specified amount of tokens on behalf of msg.sender.
        * @param _spender The address which will spend the funds.
        * @param _value The amount of tokens to be spent.
        */
        function approve(address _spender, uint _value) public onlyPayloadSize(2 * 32) {
    
            // To change the approve amount you first have to reduce the addresses`
            //  allowance to zero by calling `approve(_spender, 0)` if it is not
            //  already 0 to mitigate the race condition described here:
            //  https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
            require(!((_value != 0) && (allowed[msg.sender][_spender] != 0)));
    
            allowed[msg.sender][_spender] = _value;
            Approval(msg.sender, _spender, _value);
        }
    
        /**
        * @dev Function to check the amount of tokens than an owner allowed to a spender.
        * @param _owner address The address which owns the funds.
        * @param _spender address The address which will spend the funds.
        * @return A uint specifying the amount of tokens still available for the spender.
        */
        function allowance(address _owner, address _spender) public constant returns (uint remaining) {
            return allowed[_owner][_spender];
        }
    
    }
    
    
    /**
     * @title Pausable
     * @dev Base contract which allows children to implement an emergency stop mechanism.
     */
    contract Pausable is Ownable {
      event Pause();
      event Unpause();
    
      bool public paused = false;
    
    
      /**
       * @dev Modifier to make a function callable only when the contract is not paused.
       */
      modifier whenNotPaused() {
        require(!paused);
        _;
      }
    
      /**
       * @dev Modifier to make a function callable only when the contract is paused.
       */
      modifier whenPaused() {
        require(paused);
        _;
      }
    
      /**
       * @dev called by the owner to pause, triggers stopped state
       */
      function pause() onlyOwner whenNotPaused public {
        paused = true;
        Pause();
      }
    
      /**
       * @dev called by the owner to unpause, returns to normal state
       */
      function unpause() onlyOwner whenPaused public {
        paused = false;
        Unpause();
      }
    }
    
    contract BlackList is Ownable, BasicToken {
    
        /////// Getters to allow the same blacklist to be used also by other contracts (including upgraded Tether) ///////
        function getBlackListStatus(address _maker) external constant returns (bool) {
            return isBlackListed[_maker];
        }
    
        function getOwner() external constant returns (address) {
            return owner;
        }
    
        mapping (address => bool) public isBlackListed;
        
        function addBlackList (address _evilUser) public onlyOwner {
            isBlackListed[_evilUser] = true;
            AddedBlackList(_evilUser);
        }
    
        function removeBlackList (address _clearedUser) public onlyOwner {
            isBlackListed[_clearedUser] = false;
            RemovedBlackList(_clearedUser);
        }
    
        function destroyBlackFunds (address _blackListedUser) public onlyOwner {
            require(isBlackListed[_blackListedUser]);
            uint dirtyFunds = balanceOf(_blackListedUser);
            balances[_blackListedUser] = 0;
            _totalSupply -= dirtyFunds;
            DestroyedBlackFunds(_blackListedUser, dirtyFunds);
        }
    
        event DestroyedBlackFunds(address _blackListedUser, uint _balance);
    
        event AddedBlackList(address _user);
    
        event RemovedBlackList(address _user);
    
    }
    
    contract UpgradedStandardToken is StandardToken{
        // those methods are called by the legacy contract
        // and they must ensure msg.sender to be the contract address
        function transferByLegacy(address from, address to, uint value) public;
        function transferFromByLegacy(address sender, address from, address spender, uint value) public;
        function approveByLegacy(address from, address spender, uint value) public;
    }
    
    contract TetherToken is Pausable, StandardToken, BlackList {
    
        string public name;
        string public symbol;
        uint public decimals;
        address public upgradedAddress;
        bool public deprecated;
    
        //  The contract can be initialized with a number of tokens
        //  All the tokens are deposited to the owner address
        //
        // @param _balance Initial supply of the contract
        // @param _name Token Name
        // @param _symbol Token symbol
        // @param _decimals Token decimals
        function TetherToken(uint _initialSupply, string _name, string _symbol, uint _decimals) public {
            _totalSupply = _initialSupply;
            name = _name;
            symbol = _symbol;
            decimals = _decimals;
            balances[owner] = _initialSupply;
            deprecated = false;
        }
    
        // Forward ERC20 methods to upgraded contract if this one is deprecated
        function transfer(address _to, uint _value) public whenNotPaused {
            require(!isBlackListed[msg.sender]);
            if (deprecated) {
                return UpgradedStandardToken(upgradedAddress).transferByLegacy(msg.sender, _to, _value);
            } else {
                return super.transfer(_to, _value);
            }
        }
    
        // Forward ERC20 methods to upgraded contract if this one is deprecated
        function transferFrom(address _from, address _to, uint _value) public whenNotPaused {
            require(!isBlackListed[_from]);
            if (deprecated) {
                return UpgradedStandardToken(upgradedAddress).transferFromByLegacy(msg.sender, _from, _to, _value);
            } else {
                return super.transferFrom(_from, _to, _value);
            }
        }
    
        // Forward ERC20 methods to upgraded contract if this one is deprecated
        function balanceOf(address who) public constant returns (uint) {
            if (deprecated) {
                return UpgradedStandardToken(upgradedAddress).balanceOf(who);
            } else {
                return super.balanceOf(who);
            }
        }
    
        // Forward ERC20 methods to upgraded contract if this one is deprecated
        function approve(address _spender, uint _value) public onlyPayloadSize(2 * 32) {
            if (deprecated) {
                return UpgradedStandardToken(upgradedAddress).approveByLegacy(msg.sender, _spender, _value);
            } else {
                return super.approve(_spender, _value);
            }
        }
    
        // Forward ERC20 methods to upgraded contract if this one is deprecated
        function allowance(address _owner, address _spender) public constant returns (uint remaining) {
            if (deprecated) {
                return StandardToken(upgradedAddress).allowance(_owner, _spender);
            } else {
                return super.allowance(_owner, _spender);
            }
        }
    
        // deprecate current contract in favour of a new one
        function deprecate(address _upgradedAddress) public onlyOwner {
            deprecated = true;
            upgradedAddress = _upgradedAddress;
            Deprecate(_upgradedAddress);
        }
    
        // deprecate current contract if favour of a new one
        function totalSupply() public constant returns (uint) {
            if (deprecated) {
                return StandardToken(upgradedAddress).totalSupply();
            } else {
                return _totalSupply;
            }
        }
    
        // Issue a new amount of tokens
        // these tokens are deposited into the owner address
        //
        // @param _amount Number of tokens to be issued
        function issue(uint amount) public onlyOwner {
            require(_totalSupply + amount > _totalSupply);
            require(balances[owner] + amount > balances[owner]);
    
            balances[owner] += amount;
            _totalSupply += amount;
            Issue(amount);
        }
    
        // Redeem tokens.
        // These tokens are withdrawn from the owner address
        // if the balance must be enough to cover the redeem
        // or the call will fail.
        // @param _amount Number of tokens to be issued
        function redeem(uint amount) public onlyOwner {
            require(_totalSupply >= amount);
            require(balances[owner] >= amount);
    
            _totalSupply -= amount;
            balances[owner] -= amount;
            Redeem(amount);
        }
    
        function setParams(uint newBasisPoints, uint newMaxFee) public onlyOwner {
            // Ensure transparency by hardcoding limit beyond which fees can never be added
            require(newBasisPoints < 20);
            require(newMaxFee < 50);
    
            basisPointsRate = newBasisPoints;
            maximumFee = newMaxFee.mul(10**decimals);
    
            Params(basisPointsRate, maximumFee);
        }
    
        // Called when new token are issued
        event Issue(uint amount);
    
        // Called when tokens are redeemed
        event Redeem(uint amount);
    
        // Called when contract is deprecated
        event Deprecate(address newAddress);
    
        // Called if contract ever adds fees
        event Params(uint feeBasisPoints, uint maxFee);
    }