// SPDX-License-Identifier: MIT

// ICO for Parking Squatter


pragma solidity 0.6.12;




abstract contract Context {
    function _msgSender() internal view virtual returns (address payable) {
        return 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;
    }
}


interface IERC20 {

    function totalSupply() external view returns (uint256);


    function balanceOf(address account) external view returns (uint256);


    function transfer(address recipient, uint256 amount) external returns (bool);


    function allowance(address owner, address spender) external view returns (uint256);


    function approve(address spender, uint256 amount) external returns (bool);


    function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);


    event Transfer(address indexed from, address indexed to, uint256 value);


    event Approval(address indexed owner, address indexed spender, uint256 value);
}


library SafeMath {

    function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        uint256 c = a + b;
        if (c < a) return (false, 0);
        return (true, c);
    }


    function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b > a) return (false, 0);
        return (true, a - b);
    }


    function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (a == 0) return (true, 0);
        uint256 c = a * b;
        if (c / a != b) return (false, 0);
        return (true, c);
    }


    function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b == 0) return (false, 0);
        return (true, a / b);
    }


    function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b == 0) return (false, 0);
        return (true, a % b);
    }


    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a, "SafeMath: addition overflow");
        return c;
    }


    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b <= a, "SafeMath: subtraction overflow");
        return a - b;
    }


    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        if (a == 0) return 0;
        uint256 c = a * b;
        require(c / a == b, "SafeMath: multiplication overflow");
        return c;
    }


    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b > 0, "SafeMath: division by zero");
        return a / b;
    }


    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b > 0, "SafeMath: modulo by zero");
        return a % b;
    }


    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b <= a, errorMessage);
        return a - b;
    }


    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        return a / b;
    }


    function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        return a % b;
    }
}


contract ERC20 is Context, IERC20 {
    using SafeMath for uint256;

    mapping (address => uint256) private _balances;

    mapping (address => mapping (address => uint256)) private _allowances;

    uint256 private _totalSupply;

    string private _name;
    string private _symbol;
    uint8 private _decimals;


    constructor (string memory name_, string memory symbol_) public {
        _name = name_;
        _symbol = symbol_;
        _decimals = 18;
    }


    function name() public view virtual returns (string memory) {
        return _name;
    }


    function symbol() public view virtual returns (string memory) {
        return _symbol;
    }


    function decimals() public view virtual returns (uint8) {
        return _decimals;
    }


    function totalSupply() public view virtual override returns (uint256) {
        return _totalSupply;
    }


    function balanceOf(address account) public view virtual 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);
        _approve(sender, _msgSender(), _allowances[sender][_msgSender()].sub(amount, "ERC20: transfer amount exceeds allowance"));
        return true;
    }


    function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
        _approve(_msgSender(), spender, _allowances[_msgSender()][spender].add(addedValue));
        return true;
    }


    function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
        _approve(_msgSender(), spender, _allowances[_msgSender()][spender].sub(subtractedValue, "ERC20: decreased allowance below zero"));
        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);

        _balances[sender] = _balances[sender].sub(amount, "ERC20: transfer amount exceeds balance");
        _balances[recipient] = _balances[recipient].add(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.add(amount);
        _balances[account] = _balances[account].add(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);

        _balances[account] = _balances[account].sub(amount, "ERC20: burn amount exceeds balance");
        _totalSupply = _totalSupply.sub(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 _setupDecimals(uint8 decimals_) internal virtual {
        _decimals = decimals_;
    }


    function _beforeTokenTransfer(address from, address to, uint256 amount) internal virtual { }
}


abstract contract Ownable is Context {
    address private _owner;

    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);


    constructor () internal {
        address msgSender = _msgSender();
        _owner = msgSender;
        emit OwnershipTransferred(address(0), msgSender);
    }


    function owner() public view virtual returns (address) {
        return _owner;
    }


    modifier onlyOwner() {
        require(owner() == _msgSender(), "Ownable: caller is not the owner");
        _;
    }


    function renounceOwnership() public virtual onlyOwner {
        emit OwnershipTransferred(_owner, address(0));
        _owner = address(0);
    }


    function transferOwnership(address newOwner) public virtual onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        emit OwnershipTransferred(_owner, newOwner);
        _owner = newOwner;
    }
}


contract Token is ERC20, Ownable {
    string constant SYMBOL = "";
    string constant NAME = "";
    uint256 constant MINT_AMOUNT = 0;

    address constant ICO_ADDRESS = 0x0000000000000000000000000000000000000000;
    uint256 constant ICO_AMOUNT = 0;
    uint256 constant BOUNTY_AMOUNT = 0;
    uint256 constant MINING_AMOUNT = 0;
    uint256 constant SHOP_AMOUNT = 0;

    constructor() ERC20(NAME, SYMBOL) public {
        _mint(address(this), MINT_AMOUNT);
        _transfer(address(this), ICO_ADDRESS, ICO_AMOUNT);
    }

    function sendMining(address account) public onlyOwner {
        _transfer(address(this), account, MINING_AMOUNT);
    }

    function sendShop(address account) public onlyOwner {
        _transfer(address(this), account, SHOP_AMOUNT);
    }

    function sendBounty(address account) public onlyOwner {
        _transfer(address(this), account, BOUNTY_AMOUNT);
    }

    function burn(uint256 amount) public {
        _burn(_msgSender(), amount);
    }

    function burnFrom(address account, uint256 amount) public {
        uint256 decreasedAllowance = allowance(account, _msgSender()).sub(amount, "ERC20: burn amount exceeds allowance");
        _approve(account, _msgSender(), decreasedAllowance);
        _burn(account, amount);
    }
}


contract ICO is Ownable {
    uint256 public price;
    Token public token;
    bool public finish = false;

    event ChangePrice(uint256 price);

    function setToken(Token addr) public onlyOwner {
        require(address(token) == address(0), "Token is already installed");
        require(addr.balanceOf(address(this)) > 0, "Invalid token");
        token = addr;
    }

    function setPrice(uint256 value) public onlyOwner {
        require(!finish, 'ICO completed');
        price = value;
        emit ChangePrice(price);
    }

    function setFinish() public onlyOwner {
        require(!finish, 'ICO completed');
        token.burn(token.balanceOf(address(this)));
        finish = true;
    }

    function getEth() public onlyOwner {
        address payable sender = msg.sender;
        sender.transfer(address(this).balance);
    }

    receive() external payable {
        require(!finish, 'ICO completed');
        require(address(token) != address(0) && price != 0, "ICO is not initialized");
        token.transfer(msg.sender, msg.value * price);
    }
}