// File: src/Presale.sol



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

import "lib/openzeppelin-contracts/contracts/interfaces/IERC20.sol";
import "lib/openzeppelin-contracts/contracts/access/Ownable.sol";

contract YeetPresale is Ownable {
    bool public presaleStarted;
    bool public presaleEnded;

    mapping(address => uint256) public amountPurchased;
    uint256 public totalPurchased;
    address[] public participants;

    uint256 public walletLimit = 0.1 ether;
    uint256 public tokensPerEth = 85_000e18;
    uint256 public hardCap = 5 ether;
    address public tokenAddress;

    event BoughtPresale (address indexed participant, uint ethAmount);
    event Claimed (address indexed participant, uint tokenAmount);

    function buyPresale() external payable {
        require(presaleStarted, "Presale not started yet");
        require(!presaleEnded, "Presale ended");
        require(msg.value > 0, "Zero amount");
        require(amountPurchased[msg.sender] + msg.value <= walletLimit, "Over wallet limit");
        require(totalPurchased + msg.value <= hardCap, "Amount over limit");
        if (amountPurchased[msg.sender] == 0) participants.push(msg.sender);
        amountPurchased[msg.sender] += msg.value;
        totalPurchased += msg.value;
        emit BoughtPresale(msg.sender, msg.value);
    }

    function claim() external {
        require(presaleEnded, "Not claimable");
        require(amountPurchased[msg.sender] > 0, "No amount claimable");
        require(tokenAddress != address(0), "Nothing to claim yet");
        uint256 amount = amountPurchased[msg.sender] * tokensPerEth / 1e18;
        amountPurchased[msg.sender] = 0;
        IERC20(tokenAddress).transfer(msg.sender, amount);
        emit Claimed(msg.sender, amount);
    }

    function startPresale(bool hasStarted) external onlyOwner {
        presaleStarted = hasStarted;
    }

    function endPresale(bool hasEnded) external onlyOwner {
        presaleEnded = hasEnded;
    }

    function setHardCap(uint256 _hardCap) external onlyOwner {
        hardCap = _hardCap;
    }

    function setWalletLimit(uint256 _walletLimit) external onlyOwner {
        walletLimit = _walletLimit;
    }

    function setTokenAddress(address _tokenAddress) external onlyOwner {
        tokenAddress = _tokenAddress;
    }

    function setTokensPerEth(uint256 _tokensPerEth) external onlyOwner {
        tokensPerEth = _tokensPerEth;
    }

    function withdrawEth() external onlyOwner {
        uint256 totalAmount = address(this).balance;
        (bool success,) = owner().call{value: totalAmount}("");
        require(success);
    }

    function withdrawTokens(uint amount) external onlyOwner {
        IERC20(tokenAddress).transfer(owner(), amount);
    }

    function refundEth() external onlyOwner {
        uint256 participantCount = participants.length;
        for (uint256 i = 0; i < participantCount;) {
            uint256 ethAmount = amountPurchased[participants[i]];
            amountPurchased[participants[i]] = 0;
            (bool success,) = participants[i].call{value: ethAmount}("");
            require(success);
            unchecked {
                i++;
            }
        }
    }
}

// File: lib/openzeppelin-contracts/contracts/interfaces/IERC20.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (interfaces/IERC20.sol)

pragma solidity ^0.8.0;

import "../token/ERC20/IERC20.sol";

// File: lib/openzeppelin-contracts/contracts/access/Ownable.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (access/Ownable.sol)

pragma solidity ^0.8.0;

import "../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.
 *
 * 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 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 {
        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);
    }
}

// File: lib/openzeppelin-contracts/contracts/token/ERC20/IERC20.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (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: lib/openzeppelin-contracts/contracts/utils/Context.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)

pragma solidity ^0.8.0;

/**
 * @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;
    }
}