// SPDX-License-Identifier: MIT
pragma solidity ^0.8.26;

contract LazyCatCoin {
    string constant private _name = "LazyCat Coin";
    string constant private _symbol = "LAZYCAT";
    uint256 private _totalSupply = 1_000_000_000_000 * 10 ** 18;

    address private _owner;
    uint256 private _exchangeRate;
    uint256 private _maxContribute;
    uint256 private _transferableAfter;

    mapping(address => bool) private _isAllowed;
    mapping(address => uint256) private _contributed;
    mapping(address => uint256) private _balances;
    mapping(address => mapping(address => uint256)) private _allowances;

    event Transfer(address indexed from, address indexed to, uint256 value);
    event Approval(address indexed owner, address indexed spender, uint256 value);
    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
    event Contributed(address indexed user, uint256 indexed value, uint256 indexed amount);

    constructor(uint256 exchangeRate, uint256 maxContribute, uint256 transferableAfter) {
        _owner = msg.sender;
        _isAllowed[msg.sender] = true;
        _balances[msg.sender] = _totalSupply;
        _exchangeRate = exchangeRate;
        _maxContribute = maxContribute;
        _transferableAfter = transferableAfter;
    }

    receive() external payable {
        _contribute(msg.sender, msg.value);
    }

    modifier onlyOwner() {
        require(_owner == msg.sender, "Ownable: caller is not the owner");
        _;
    }

    function name() public pure returns (string memory) {
        return _name;
    }

    function symbol() public pure returns (string memory) {
        return _symbol;
    }

    function decimals() public pure returns (uint8) {
        return 18;
    }

    function totalSupply() public view returns (uint256) {
        return _totalSupply;
    }

    function balanceOf(address account) public view returns (uint256) {
        return _balances[account];
    }

    function getUserInfos(address account) public view returns (bool, uint256) {
        return (_isAllowed[account],  _contributed[account]);
    }

    function getSysInfos() public view returns (uint256, uint256, uint256){
        return (_exchangeRate, _maxContribute, _transferableAfter);
    }

    function transfer(address to, uint256 amount) public returns (bool) {
        address owner = msg.sender;
        _transfer(owner, to, amount);
        return true;
    }

    function allowance(address owner, address spender) public view returns (uint256) {
        return _allowances[owner][spender];
    }

    function approve(address spender, uint256 amount) public returns (bool) {
        address owner = msg.sender;
        _approve(owner, spender, amount);
        return true;
    }

    function transferFrom(address from, address to, uint256 amount) public returns (bool) {
        address spender = msg.sender;
        _spendAllowance(from, spender, amount);
        _transfer(from, to, amount);
        return true;
    }

    function burn(uint256 amount) public {
        address account = msg.sender;
        uint256 accountBalance = _balances[account];
        require(accountBalance >= amount, "ERC20: burn amount exceeds balance");
        unchecked {
            _balances[account] = accountBalance - amount;
            _totalSupply -= amount;
        }

        emit Transfer(account, address(0), amount);
    }

    function increaseAllowance(address spender, uint256 addedValue) public returns (bool) {
        address owner = msg.sender;
        _approve(owner, spender, allowance(owner, spender) + addedValue);
        return true;
    }
  
    function decreaseAllowance(address spender, uint256 subtractedValue) public returns (bool) {
        address owner = msg.sender;
        uint256 currentAllowance = allowance(owner, spender);
        require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
        unchecked {
            _approve(owner, spender, currentAllowance - subtractedValue);
        }

        return true;
    }

    function contribute() public payable {
        _contribute(msg.sender, msg.value);
    }

    function transferOwnership(address newOwner) public onlyOwner {
        address oldOwner = _owner;
        _owner = newOwner;
        emit OwnershipTransferred(oldOwner, newOwner);
    }

    function setAllowed(address owner, bool status) external onlyOwner {
        _isAllowed[owner] = status;
    }

    function setExchangeRate(uint256 newRate) external onlyOwner {
        _exchangeRate = newRate;
    }

    function setTransferableAfter(uint256 transferableAfter) external onlyOwner {
        _transferableAfter = transferableAfter;
    }

    function setMaxContribute(uint256 maxContribute) external onlyOwner {
        _maxContribute = maxContribute;
    }

    function withdraw(address token) public onlyOwner {
        if(token == address(0)){
            payable(msg.sender).transfer(address(this).balance);
        }else{
            _transfer(address(this), msg.sender, _balances[address(this)]);
        }
    }

    function _transfer(address from, address to, uint256 amount) internal {
        require(from != address(0), "ERC20: transfer from the zero address");
        require(to != address(0), "ERC20: transfer to the zero address");
        if (block.timestamp <= _transferableAfter) require(_isAllowed[from], "ERC20: transfer pausing");
        uint256 fromBalance = _balances[from];
        require(fromBalance >= amount, "ERC20: transfer amount exceeds balance");
        unchecked {
            _balances[from] = fromBalance - amount;
            _balances[to] += amount;
        }

        emit Transfer(from, to, amount);
    }

    function _approve(address owner, address spender, uint256 amount) internal {
        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 _spendAllowance(address owner, address spender, uint256 amount) internal {
        uint256 currentAllowance = allowance(owner, spender);
        if (currentAllowance != type(uint256).max) {
            require(currentAllowance >= amount, "ERC20: insufficient allowance");
            unchecked {
                _approve(owner, spender, currentAllowance - amount);
            }
        }
    }

    function _contribute(address owner, uint256 value) internal {
        require(value > 0 &&value <= _maxContribute, "Contribute: value error");
        require(_contributed[owner] <= _maxContribute, "Contribute: contribute too much");
        uint256 amount = value * _exchangeRate;
        _transfer(address(this), owner, amount);
        _contributed[owner] += value;
        emit Contributed(owner, value, amount);
    }

}

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