pragma solidity ^0.8.0;


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);
}

interface IERC20Metadata is IERC20 {
    
    function name() external view returns (string memory);

    
    function symbol() external view returns (string memory);

    
    function decimals() external view returns (uint8);
}

abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes calldata) {
        return msg.data;
    }
}

contract ERC20 is Context, IERC20, IERC20Metadata {
    mapping(address => uint256) private _balances;

    mapping(address => mapping(address => uint256)) private _allowances;

    uint256 private _totalSupply;

    string private _name;
    string private _symbol;

    
    constructor(string memory name_, string memory symbol_) {
        _name = name_;
        _symbol = symbol_;
    }

    
    function name() public view virtual override returns (string memory) {
        return _name;
    }

    
    function symbol() public view virtual override returns (string memory) {
        return _symbol;
    }

    
    function decimals() public view virtual override returns (uint8) {
        return 18;
    }

    
    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);

        uint256 currentAllowance = _allowances[sender][_msgSender()];
        require(currentAllowance >= amount, "ERC20: transfer amount exceeds allowance");
        unchecked {
            _approve(sender, _msgSender(), currentAllowance - amount);
        }

        return true;
    }

    
    function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
        _approve(_msgSender(), spender, _allowances[_msgSender()][spender] + addedValue);
        return true;
    }

    
    function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
        uint256 currentAllowance = _allowances[_msgSender()][spender];
        require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
        unchecked {
            _approve(_msgSender(), spender, currentAllowance - subtractedValue);
        }

        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] += amount;

        emit Transfer(sender, recipient, amount);

        _afterTokenTransfer(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 += amount;
        _balances[account] += amount;
        emit Transfer(address(0), account, amount);

        _afterTokenTransfer(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 -= amount;

        emit Transfer(account, address(0), amount);

        _afterTokenTransfer(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 {}

    
    function _afterTokenTransfer(
        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() {
        _setOwner(_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 {
        _setOwner(address(0));
    }

    
    function transferOwnership(address newOwner) public virtual onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        _setOwner(newOwner);
    }

    function _setOwner(address newOwner) private {
        address oldOwner = _owner;
        _owner = newOwner;
        emit OwnershipTransferred(oldOwner, newOwner);
    }
}

contract InvaderToken is ERC20("Invader", "INVDR"), Ownable {

  address public ETHEREAN_EMPIRE_CONTRACT_ADDRESS;

  event RewardClaimed(address indexed claimer, uint amount);

  function setEthereanEmpireContractAddress(address _contractAddress) external onlyOwner(){
    ETHEREAN_EMPIRE_CONTRACT_ADDRESS = _contractAddress;
  }

  function claimReward(address _claimer, uint _amount) external {
    
    require(_msgSender() == address(ETHEREAN_EMPIRE_CONTRACT_ADDRESS));
    _mint(_claimer, _amount);
    emit RewardClaimed(_claimer, _amount);
  }

  function burnFrom(address _from, uint _amount) external {
    uint256 currentAllowance = allowance(_from, _msgSender());
    require(currentAllowance >= _amount, "ERC20: burn amount exceeds allowance");
    unchecked {
        _approve(_from, _msgSender(), currentAllowance - _amount);
    }
    _burn(_from, _amount);
  }
}