// File: @openzeppelin/contracts/token/ERC20/IERC20.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/IERC20.sol)

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);

    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);

    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);

    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);

    /**
     * @dev Moves `amount` tokens from the caller's account to `to`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address to, uint256 amount) external returns (bool);

    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);

    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);

    /**
     * @dev Moves `amount` tokens from `from` to `to` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(address from, address to, uint256 amount) external returns (bool);
}

// File: contracts/MultipleTimeLock.sol



// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

import "@openzeppelin/contracts/token/ERC20/IERC20.sol";

contract MultipleTimeLock {
    struct TimeLock {
        address token;
        uint256 releaseTime;
    }

    mapping(address => TimeLock) public timeLocks;

    address public immutable beneficiary;

    /**
     * @dev Check if the given address is the beneficiary
     */
    modifier onlyBeneficiary() {
        require(msg.sender == beneficiary, "onlyBeneficiary");
        _;
    }

    /**
     * @dev Deploys a timelock instance that is able to hold tokens and will only release them to the deployer after the releaseTime
     */
    constructor() {
        beneficiary = msg.sender;
    }

    /**
     * @dev Create a timelock instance for one token. Could be called only one time by token
     */
    function addTimeLock(address _token, uint256 _releaseTime) public onlyBeneficiary {
        require(_releaseTime > block.timestamp, "release time is before current time");
        
        TimeLock storage timeLock = timeLocks[_token];
        require(timeLocks[_token].token == address(0), "TimeLock already exist for this token");

        timeLock.token = _token;
        timeLock.releaseTime = _releaseTime;
    }

    /**
     * @dev Increase the lock, can never be lower than the previous config
     */
    function increaseTimeLock(address _token, uint256 _releaseTime) public onlyBeneficiary {
        require(_releaseTime > block.timestamp, "release time is before current time");
        
        TimeLock storage timeLock = timeLocks[_token];
        require(timeLocks[_token].token == _token, "TimeLock not exist");
        require(_releaseTime > timeLock.releaseTime, "release time is before the current lock time");
        
        timeLock.releaseTime = _releaseTime;
    }

    /**
     * @dev Transfers tokens held by the timelock to the beneficiary. Will only succeed if invoked after the release
     * time.
     */
    function release(address _token) public onlyBeneficiary {
        TimeLock memory timeLock = timeLocks[_token];
        require(block.timestamp >= timeLock.releaseTime, "current time is before release time");

        uint256 amount = IERC20(_token).balanceOf(address(this));
        require(amount > 0, "no tokens to release");

        IERC20(_token).transfer(beneficiary, amount);
    }

    function getTimeLock(address _token) external view returns (TimeLock memory) {
        return timeLocks[_token];
    }
}