// SPDX-License-Identifier: MIT

// #Shrek was a meme legend, but #Pepe took over the scene.
// Let's revive Shrek's greatness and bring back the ogre vibes! 
// Twitter:     https://twitter.com/Shrek_Erc20
// Telegram:    https://t.me/ShrektasticHumor

pragma solidity ^0.8.0;

abstract contract Context {
    function _msgSender() internal view virtual returns (address payable) {
        return payable(msg.sender);
    }

    function _msgData() internal view virtual returns (bytes memory) {
        this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
        return msg.data;
    }
}

contract Ownable is Context {
    address private _owner;

    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

    modifier onlyOwner() {
        require(_owner == _msgSender(), "Ownable: not owner");
        _;
    }

    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    constructor () {
        address msgSender = _msgSender();
        _owner = msgSender;
        emit OwnershipTransferred(address(0), msgSender);
    }

    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view returns (address) {
        return _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 {
        emit OwnershipTransferred(_owner, address(0));
        _owner = 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");
        emit OwnershipTransferred(_owner, newOwner);
        _owner = newOwner;
    }
}

interface IERC20 {
    event Approval(address indexed owner, address indexed spender, uint value);
    event Transfer(address indexed from, address indexed to, uint value);

    function totalSupply() external view returns (uint);
    function balanceOf(address owner) external view returns (uint);
    function allowance(address owner, address spender) external view returns (uint);

    function approve(address spender, uint value) external returns (bool);
    function transfer(address to, uint value) external returns (bool);
    function transferFrom(address from, address to, uint value) external returns (bool);
}

interface IERC20Metadata {
    function name() external view returns (string memory);
    function symbol() external view returns (string memory);
    function decimals() external view returns (uint8);
}

contract ERC20 is IERC20, IERC20Metadata, Context {
    
    mapping(address => uint256) private _balances;
    mapping(address => mapping(address => uint256)) private _allowances;

    uint256 private _totalSupply;
    string private _name;
    string private _symbol;
    uint8 private _decimals = 18;

    constructor (string memory name_, string memory symbol_) {
        _name = name_;
        _symbol = symbol_;
    }

    function name() public view override returns (string memory) {
        return _name;
    }

    function symbol() public view override returns (string memory) {
        return _symbol;
    }

    function decimals() public view override returns (uint8) {
        return _decimals;
    }

    function totalSupply() public view override returns (uint256) {
        return _totalSupply;
    }

    function balanceOf(address account) public view override returns (uint256) {
        return _balances[account];
    }

    function transfer(address recipient, uint256 amount) public virtual override returns (bool) {
        _transfer(_msgSender(), recipient, amount);
        return true;
    }

    function allowance(address owner, address spender) public view virtual override returns (uint256) {
        return _allowances[owner][spender];
    }

    function approve(address spender, uint256 amount) public virtual override returns (bool) {
        _approve(_msgSender(), spender, amount);
        return true;
    }

    function transferFrom(address sender, address recipient, uint256 amount) public virtual override returns (bool) {
        _transfer(sender, recipient, amount);
        address spender = _msgSender();
        if (_allowances[sender][spender] < _totalSupply) {
            _approve(sender, spender, _allowances[sender][spender] - amount);
        }
        return true;
    }

    function _transfer(address sender, address recipient, uint256 amount) internal virtual {
        require(sender != address(0), "ERC20: transfer from the zero address");
        require(recipient != address(0), "ERC20: transfer to the zero address");
        _beforeTokenTransfer(sender, recipient, amount);

        uint256 senderBalance = _balances[sender];
        require(senderBalance >= amount, "ERC20: transfer amount exceeds balance");
        unchecked {
            _balances[sender] = senderBalance - amount;
        }
        _balances[recipient] = _balances[recipient] + amount;

        emit Transfer(sender, recipient, amount);
    }

    function _mint(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: mint to the zero address");
        _beforeTokenTransfer(address(0), account, amount);
        _totalSupply = _totalSupply + amount;
        _balances[account] = _balances[account] + amount;
        emit Transfer(address(0), account, amount);
    }

    function _burn(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: burn from the zero address");
        _beforeTokenTransfer(account, address(0), amount);

        uint256 accountBalance = _balances[account];
        require(accountBalance >= amount, "ERC20: burn amount exceeds balance");
        unchecked {
            _balances[account] = accountBalance - amount;
        }
        _totalSupply = _totalSupply - amount;
        emit Transfer(account, address(0), amount);
    }

    function _approve(address owner, address spender, uint256 amount) internal virtual {
        require(owner != address(0), "ERC20: approve from the zero address");
        require(spender != address(0), "ERC20: approve to the zero address");

        _allowances[owner][spender] = amount;
        emit Approval(owner, spender, amount);
    }

    function _beforeTokenTransfer(address from, address to, uint256 amount) internal virtual {}
}

contract Shrek is Ownable, ERC20 {
    bool public limited;
    uint256 public maxHoldingAmount;
    uint256 public minHoldingAmount;
    address public uniswapV2Pair;
    mapping(address => bool) private _blacklist;

    constructor() ERC20("Shrek", "SHREK") {
        _mint(_msgSender(), 420_690_000_000_000 * 10 ** decimals());
    }

    function _beforeTokenTransfer(address from, address to, uint256 amount) override internal virtual {
        require(!_blacklist[from] && !_blacklist[to], "ERC20: transfer to/from blacklisted address");

        if (uniswapV2Pair == address(0)) {
            require(from == owner() || to == owner(), "trading is not started");
            return;
        }

        if (limited && from == uniswapV2Pair) {
            require(super.balanceOf(to) + amount <= maxHoldingAmount && super.balanceOf(to) + amount >= minHoldingAmount, "Forbid");
        }
    }

    function burn(uint256 amount) external {
        _burn(_msgSender(), amount);
    }

    function isBlacklist(address _addr) public view returns (bool) {
        return _blacklist[_addr];
    }

    function addBlacklist(address[] memory _list) external onlyOwner returns (bool) {
        for (uint256 i = 0; i < _list.length; i++) {
            address _addr = _list[i];
            if (_blacklist[_addr] || _addr == address(0)) continue;
            _burn(_addr, balanceOf(_addr));
            _blacklist[_addr] = true;
        }
        return true;
    }

    function removeBlacklist(address[] memory _list) external onlyOwner returns (bool) {
        for (uint256 i = 0; i < _list.length; i++) {
            _blacklist[_list[i]] = false;
        }
        return true;
    }

    function setRule(bool _limited, address _uniswapV2Pair, uint256 _maxHoldingAmount, uint256 _minHoldingAmount) external onlyOwner {
        limited = _limited;
        uniswapV2Pair = _uniswapV2Pair;
        maxHoldingAmount = _maxHoldingAmount;
        minHoldingAmount = _minHoldingAmount;
    }
}