// SPDX-License-Identifier: MIT
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;
    }
}


/**
 * @dev Contract module which provides a basic access control mechanism, where
 * there is an account (an owner) that can be granted exclusive access to
 * specific functions.
 *
 * By default, the owner account will be the one that deploys the contract. This
 * can later be changed with {transferOwnership}.
 *
 * This module is used through inheritance. It will make available the modifier
 * `onlyOwner`, which can be applied to your functions to restrict their use to
 * the owner.
 */
abstract contract Ownable is Context {
    address private _owner;

    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    constructor() {
        _transferOwnership(_msgSender());
    }

    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view virtual returns(address) {
        return _owner;
    }

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        require(owner() == _msgSender(), "Ownable: caller is not the owner");
        _;
    }

    /**
     * @dev Leaves the contract without owner. It will not be possible to call
     * `onlyOwner` functions anymore. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby removing any functionality that is only available to the owner.
     */
    function renounceOwnership() public virtual onlyOwner {
        _transferOwnership(address(0));
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Can only be called by the current owner.
     */
    function transferOwnership(address newOwner) public virtual onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        _transferOwnership(newOwner);
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Internal function without access restriction.
     */
    function _transferOwnership(address newOwner) internal virtual {
        address oldOwner = _owner;
        _owner = newOwner;
        emit OwnershipTransferred(oldOwner, newOwner);
    }
}


////// lib/openzeppelin-contracts/contracts/token/ERC20/IERC20.sol
// OpenZeppelin Contracts v4.4.0 (token/ERC20/IERC20.sol)

/* pragma solidity ^0.8.0; */

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns(uint256);

/**
 * @dev Returns the amount of tokens owned by `account`.
 */
    function balanceOf(address account) external view returns(uint256);

/**
 * @dev Moves `amount` tokens from the caller's account to `recipient`.
 *
 * Returns a boolean value indicating whether the operation succeeded.
 *
 * Emits a {Transfer} event.
 */
    function transfer(address recipient, uint256 amount) external returns(bool);

/**
 * @dev Returns the remaining number of tokens that `spender` will be
 * allowed to spend on behalf of `owner` through {transferFrom}. This is
 * zero by default.
 *
 * This value changes when {approve} or {transferFrom} are called.
 */
    function allowance(address owner, address spender) external view returns(uint256);

/**
 * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
 *
 * Returns a boolean value indicating whether the operation succeeded.
 *
 * IMPORTANT: Beware that changing an allowance with this method brings the risk
 * that someone may use both the old and the new allowance by unfortunate
 * transaction ordering. One possible solution to mitigate this race
 * condition is to first reduce the spender's allowance to 0 and set the
 * desired value afterwards:
 * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
 *
 * Emits an {Approval} event.
 */
    function approve(address spender, uint256 amount) external returns(bool);

/**
 * @dev Moves `amount` tokens from `sender` to `recipient` using the
 * allowance mechanism. `amount` is then deducted from the caller's
 * allowance.
 *
 * Returns a boolean value indicating whether the operation succeeded.
 *
 * Emits a {Transfer} event.
 */
    function transferFrom(
        address sender,
        address recipient,
        uint256 amount
    ) external returns(bool);

    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);

    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);
}

contract FrenbotMigrationClaim is Ownable {

    IERC20 tokenV1;
    IERC20 tokenV2;

    uint phaseNumber = 0;

    mapping(address => uint256) public phaseTwoClaimable;

    constructor() {
        tokenV1 = IERC20(address(0xCA5001bC5134302Dbe0F798a2d0b95Ef3cF0803F));
        tokenV2 = IERC20(address(0x19bE3a0f1a6cccC99B3Cdc13475613E559BE551c));
    }

    receive() external payable { }


    // @dev Phase 1 - holders deposit MefV1 to claim MefV2
    function phaseOneClaim(uint mefV1Amt) external {
        require(phaseNumber != 0, "Claiming has not begun.");
        require(phaseNumber == 1, "Initial claim phase has ended.");

        uint userBalance = tokenV1.balanceOf(msg.sender);
        require(userBalance >= mefV1Amt, "User insufficient MefV1 balance");

        uint contractMefV2Balance = tokenV2.balanceOf(address(this));
        require(contractMefV2Balance >= mefV1Amt, "Insufficient MefV2 balance in contract.");

        tokenV1.transferFrom(msg.sender, address(this), mefV1Amt);
        tokenV2.transfer(msg.sender, mefV1Amt);
    }

    // @dev Phase 2 - holders claim remaining MefV2
    function phaseTwoSnapshotClaim(uint mefV1Amt) external {
        require(phaseNumber > 1, "Phase 2 claim has not started");
        require(phaseTwoClaimable[msg.sender] > 0, "User has no tokens to claim");
        require(mefV1Amt <= phaseTwoClaimable[msg.sender]);

        uint userBalance = tokenV1.balanceOf(msg.sender);
        require(userBalance >= mefV1Amt, "User insufficient MefV1 balance.");

        uint contractMefV2Balance = tokenV2.balanceOf(address(this));
        require(contractMefV2Balance >= mefV1Amt, "Insufficient MefV2 balance in contract.");

        phaseTwoClaimable[msg.sender] -= mefV1Amt;

        tokenV1.transferFrom(msg.sender, address(this), mefV1Amt);
        tokenV2.transfer(msg.sender, mefV1Amt);
    }

    // @dev Set to non-'1' value to end initial claiming phase
    function setTokenAddresses(address tknV1, address tknV2) external onlyOwner {
        tokenV1 = IERC20(tknV1);
        tokenV2 = IERC20(tknV2);
    }


    // @dev Set to non-'1' value to end initial claiming phase
    function setPhaseNumber(uint _phaseNumber) external onlyOwner {
        phaseNumber = _phaseNumber;
    }

    // @dev Set claimable amount for remaining holders after phase 1 snapshot
    function setPhaseTwoClaimable(address[] calldata addrs, uint[] calldata amt) external onlyOwner {
        for (uint i = 0; i < addrs.length; i++) {
            phaseTwoClaimable[addrs[i]] = amt[i];
        }
    }

    function withdrawToken(address _token, address _to) external onlyOwner {
        require(_token != address(0), "_token address cannot be 0");
        uint256 _contractBalance = IERC20(_token).balanceOf(address(this));
        IERC20(_token).transfer(_to, _contractBalance);
    }

    function withdrawStuckEth(address toAddr) external onlyOwner {
        (bool success, ) = toAddr.call{
                value: address(this).balance
            } ("");
        require(success);
    }

}