// File: @openzeppelin/contracts/utils/Context.sol


// 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;
    }
}

// File: @openzeppelin/contracts/access/Ownable.sol


// OpenZeppelin Contracts (last updated v5.0.0) (access/Ownable.sol)

pragma solidity ^0.8.20;


/**
 * @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);
    }
}

// File: iotube/TransferValidatorWithPayload.sol


pragma solidity >= 0.8.0;


interface IAllowlist {
    function isAllowed(address) external view returns (bool);
    function numOfActive() external view returns (uint256);
}

interface IMinter {
    function mint(address, address, uint256) external returns(bool);
    function transferOwnership(address) external;
    function owner() external view returns(address);
}

interface IReceiver {
    function onReceive(address sender, address token, uint256 amount, bytes calldata payload) external;
}

contract TransferValidatorWithPayload is Ownable {
    event Settled(bytes32 indexed key, address[] witnesses);
    event ReceiverAdded(address receiver);
    event ReceiverRemoved(address receiver);
    event Pause();
    event Unpause();
    modifier whenNotPaused() {
        require(!paused);
        _;
    }
    bool public paused;

    mapping(bytes32 => uint256) public settles;
    mapping(address => bool) public receivers;

    IMinter[] public minters;
    IAllowlist[] public tokenLists;
    IAllowlist public witnessList;

    constructor(IAllowlist _witnessList) Ownable(msg.sender) {
        witnessList = _witnessList;
    }

    function pause() public onlyOwner {
        require(!paused, "already paused");
        paused = true;
        emit Pause();
    }

    function unpause() public onlyOwner {
        require(paused, "already unpaused");
        paused = false;
        emit Unpause();
    }

    function generateKey(address cashier, address tokenAddr, uint256 index, address from, address to, uint256 amount, bytes memory payload) public view returns(bytes32) {
        return keccak256(abi.encodePacked(address(this), cashier, tokenAddr, index, from, to, amount, payload));
    }

    function getMinter(address tokenAddr) public view returns (IMinter) {
        for (uint256 i = 0; i < tokenLists.length; i++) {
            if (tokenLists[i].isAllowed(tokenAddr)) {
                return minters[i];
            }
        }
        return minters[0];
    }

    function submit(address cashier, address tokenAddr, uint256 index, address from, address to, uint256 amount, bytes memory signatures, bytes memory payload) public whenNotPaused {
        require(amount != 0, "amount cannot be zero");
        require(to != address(0), "recipient cannot be zero");
        require(signatures.length % 65 == 0, "invalid signature length");
        bytes32 key = generateKey(cashier, tokenAddr, index, from, to, amount, payload);
        require(settles[key] == 0, "transfer has been settled");
        uint256 numOfSignatures = signatures.length / 65;
        address[] memory witnesses = new address[](numOfSignatures);
        for (uint256 i = 0; i < numOfSignatures; i++) {
            address witness = recover(key, signatures, i * 65);
            require(witnessList.isAllowed(witness), "invalid signature");
            for (uint256 j = 0; j < i; j++) {
                require(witness != witnesses[j], "duplicate witness");
            }
            witnesses[i] = witness;
        }
        require(numOfSignatures * 3 > witnessList.numOfActive() * 2, "insufficient witnesses");
        IMinter minter = getMinter(tokenAddr);
        settles[key] = block.number;
        require(minter.mint(tokenAddr, to, amount), "failed to mint token");
        if (receivers[to]) {
            IReceiver(to).onReceive(from, tokenAddr, amount, payload);
        }
        emit Settled(key, witnesses);
    }

    function numOfPairs() external view returns (uint256) {
        return tokenLists.length;
    }

    function addPair(IAllowlist _tokenList, IMinter _minter) external onlyOwner {
        tokenLists.push(_tokenList);
        minters.push(_minter);
    }

    function addReceiver(address _receiver) external onlyOwner {
        require(!receivers[_receiver], "already a receiver");
        receivers[_receiver] = true;
        emit ReceiverAdded(_receiver);
    }

    function removeReceiver(address _receiver) external onlyOwner {
        require(receivers[_receiver], "invalid receiver");
        receivers[_receiver] = false;
        emit ReceiverRemoved(_receiver);
    }

    function upgrade(address _newValidator) external onlyOwner {
        address contractAddr = address(this);
        for (uint256 i = 0; i < minters.length; i++) {
            IMinter minter = minters[i];
            if (minter.owner() == contractAddr) {
                minter.transferOwnership(_newValidator);
            }
        }
    }

    /**
    * @dev Recover signer address from a message by using their signature
    * @param hash bytes32 message, the hash is the signed message. What is recovered is the signer address.
    * @param signature bytes signature, the signature is generated using web3.eth.sign()
    */
    function recover(bytes32 hash, bytes memory signature, uint256 offset)
        internal
        pure
        returns (address)
    {
        bytes32 r;
        bytes32 s;
        uint8 v;

        // Divide the signature in r, s and v variables with inline assembly.
        assembly {
            r := mload(add(signature, add(offset, 0x20)))
            s := mload(add(signature, add(offset, 0x40)))
            v := byte(0, mload(add(signature, add(offset, 0x60))))
        }

        // Version of signature should be 27 or 28, but 0 and 1 are also possible versions
        if (v < 27) {
            v += 27;
        }

        // If the version is correct return the signer address
        if (v != 27 && v != 28) {
            return (address(0));
        }
        // solium-disable-next-line arg-overflow
        return ecrecover(hash, v, r, s);
    }
}

{
  "compilationTarget": {
    "TransferValidatorWithPayload.sol": "TransferValidatorWithPayload"
  },
  "evmVersion": "shanghai",
  "libraries": {},
  "metadata": {
    "bytecodeHash": "ipfs"
  },
  "optimizer": {
    "enabled": true,
    "runs": 200
  },
  "remappings": []
}