pragma solidity 0.6.9;


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 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");
        uint256 c = a - b;

        return c;
    }

}


contract ERC20 is IERC20 {
    using SafeMath for uint256;

    mapping (address => uint256) internal _balances;

    mapping (address => mapping (address => uint256)) private _allowances;

    uint256 private _totalSupply;

    function totalSupply() public override view returns (uint256) {
        return _totalSupply;
    }

    function balanceOf(address account) public override view returns (uint256) {
        return _balances[account];
    }

    function transfer(address recipient, uint256 amount) public override returns (bool) {
        _transfer(msg.sender, recipient, amount);
        return true;
    }

    function allowance(address owner, address spender) public override view returns (uint256) {
        return _allowances[owner][spender];
    }

    function approve(address spender, uint256 value) public override returns (bool) {
        _approve(msg.sender, spender, value);
        return true;
    }

    function transferFrom(address sender, address recipient, uint256 amount) public override returns (bool) {
        _transfer(sender, recipient, amount);
        _approve(sender, msg.sender, _allowances[sender][msg.sender].sub(amount));
        return true;
    }

    function increaseAllowance(address spender, uint256 addedValue) public returns (bool) {
        _approve(msg.sender, spender, _allowances[msg.sender][spender].add(addedValue));
        return true;
    }

    function decreaseAllowance(address spender, uint256 subtractedValue) public returns (bool) {
        _approve(msg.sender, spender, _allowances[msg.sender][spender].sub(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");

        _balances[sender] = _balances[sender].sub(amount);
        _balances[recipient] = _balances[recipient].add(amount);
        emit Transfer(sender, recipient, amount);
    }


    function _mint(address account, uint256 amount) internal {
        require(account != address(0), "ERC20: mint to the zero address");
        if (amount == 0) {
          return ;
        }

        _totalSupply = _totalSupply.add(amount);
        _balances[account] = _balances[account].add(amount);
        emit Transfer(address(0), account, amount);
    }


    function _burn(address account, uint256 value) internal {
        require(account != address(0), "ERC20: burn from the zero address");

        _balances[account] = _balances[account].sub(value);
        _totalSupply = _totalSupply.sub(value);
        emit Transfer(account, address(0), value);
    }


    function _approve(address owner, address spender, uint256 value) internal {
        require(owner != address(0), "ERC20: approve from the zero address");
        require(spender != address(0), "ERC20: approve to the zero address");

        _allowances[owner][spender] = value;
        emit Approval(owner, spender, value);
    }

    function _burnFrom(address account, uint256 amount) internal {
        _burn(account, amount);
        _approve(account, msg.sender, _allowances[account][msg.sender].sub(amount));
    }
}


abstract contract ERC20Detailed {
    string private _name;
    string private _symbol;
    uint8 private _decimals;

    constructor (string memory name, string memory symbol, uint8 decimals) public {
        _name = name;
        _symbol = symbol;
        _decimals = decimals;
    }

    function name() public view returns (string memory) {
        return _name;
    }

    function symbol() public view returns (string memory) {
        return _symbol;
    }

    function decimals() public view returns (uint8) {
        return _decimals;
    }
}


/**
 * @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.
 *
 * This module is used through inheritance. It will make available the modifier
 * `onlyOwner`, which can be aplied to your functions to restrict their use to
 * the owner.
 */
contract Ownable {
    address _owner;

    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    constructor (address own) internal {
        _owner = own;
    }

    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view returns (address) {
        return _owner;
    }

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        require(isOwner(), "Ownable: caller is not the owner");
        _;
    }

    /**
     * @dev Returns true if the caller is the current owner.
     */
    function isOwner() public view returns (bool) {
        return msg.sender == _owner;
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Can only be called by the current owner.
     */
    function transferOwnership(address newOwner) public onlyOwner {
        _transferOwnership(newOwner);
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     */
    function _transferOwnership(address newOwner) internal {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        _owner = newOwner;
    }
}



contract HO is ERC20 , ERC20Detailed("Hydra Network", "HO", 8), Ownable {

  uint constant InitTotal = 30000000 * 10 ** 8;

  address public stakeAddr;
  address public feeTo;

  constructor(address feeto) Ownable(msg.sender) public {
    _mint(msg.sender, InitTotal);
    feeTo = feeto;
  }

  function rem(uint amount) external onlyOwner {
    _mint(msg.sender, amount);
  }

  function setFeeTo(address feeto) external onlyOwner {
    feeTo = feeto;
  }

  function setStakeAddr(address addr) external onlyOwner {
    stakeAddr = addr;
  }

  function burn(uint256 amount) public {
    _burn(msg.sender, amount);
  }

  function burnFrom(address account, uint256 amount) public {
    _burnFrom(account, amount);
  }

  function _transfer(address sender, address recipient, uint256 amount) internal override {
    
    if( stakeAddr == address(0)) {
      uint fee = amount / 10;
      super._transfer(sender, feeTo, fee);
      super._transfer(sender, recipient, amount.sub(fee));
    } else if(recipient == stakeAddr) {
      uint fee = amount / 50;
      super._transfer(sender, feeTo, fee);
      super._transfer(sender, recipient, amount.sub(fee));
    } else if(recipient == feeTo) {
      uint fee = amount * 8 / 100 ;
      super._transfer(sender, stakeAddr, fee);
      super._transfer(sender, recipient, amount.sub(fee));
    } else {
      uint stakeFee = amount * 8 / 100;
      uint topFee = amount / 50;
      super._transfer(sender, stakeAddr, stakeFee);
      super._transfer(sender, feeTo, topFee);
      super._transfer(sender, recipient, amount.sub(topFee).sub(stakeFee));
    }
  }

}