pragma solidity ^0.6.2;

library Address {

    function isContract(address account) internal view returns (bool) {

        bytes32 codehash;
        bytes32 accountHash = 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470;
        assembly { codehash := extcodehash(account) }
        return (codehash != accountHash && codehash != 0x0);
    }

    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");

        (bool success, ) = recipient.call{ value: amount }("");
        require(success, "Address: unable to send value, recipient may have reverted");
    }

    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
      return functionCall(target, data, "Address: low-level call failed");
    }

    function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
        return _functionCallWithValue(target, data, 0, errorMessage);
    }

    function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
        return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
    }

    function functionCallWithValue(address target, bytes memory data, uint256 value, string memory errorMessage) internal returns (bytes memory) {
        require(address(this).balance >= value, "Address: insufficient balance for call");
        return _functionCallWithValue(target, data, value, errorMessage);
    }

    function _functionCallWithValue(address target, bytes memory data, uint256 weiValue, string memory errorMessage) private returns (bytes memory) {
        require(isContract(target), "Address: call to non-contract");

        (bool success, bytes memory returndata) = target.call{ value: weiValue }(data);
        if (success) {
            return returndata;
        } else {
            if (returndata.length > 0) {
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}

pragma solidity ^0.6.0;

abstract contract Context {
    function _msgSender() internal view virtual returns (address payable) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes memory) {
        this;
        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 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) {
        return sub(a, b, "SafeMath: subtraction overflow");
    }
  
    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b <= a, errorMessage);
        uint256 c = a - b;

        return c;
    }

    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) {
        return div(a, b, "SafeMath: division by zero");
    }

    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        uint256 c = a / b;
        return c;
    }

    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        return mod(a, b, "SafeMath: modulo by zero");
    }

    function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b != 0, errorMessage);
        return a % b;
    }

    function toInt256Safe(uint256 a) internal pure returns (int256) {
    int256 b = int256(a);
    require(b >= 0);
    return b;
  }
}


library SignedSafeMath {
    int256 constant private _INT256_MIN = -2**255;

    function mul(int256 a, int256 b) internal pure returns (int256) {
        if (a == 0) {
            return 0;
        }

        require(!(a == -1 && b == _INT256_MIN), "SignedSafeMath: multiplication overflow");

        int256 c = a * b;
        require(c / a == b, "SignedSafeMath: multiplication overflow");

        return c;
    }

    function div(int256 a, int256 b) internal pure returns (int256) {
        require(b != 0, "SignedSafeMath: division by zero");
        require(!(b == -1 && a == _INT256_MIN), "SignedSafeMath: division overflow");

        int256 c = a / b;

        return c;
    }

    function sub(int256 a, int256 b) internal pure returns (int256) {
        int256 c = a - b;
        require((b >= 0 && c <= a) || (b < 0 && c > a), "SignedSafeMath: subtraction overflow");

        return c;
    }

    function add(int256 a, int256 b) internal pure returns (int256) {
        int256 c = a + b;
        require((b >= 0 && c >= a) || (b < 0 && c < a), "SignedSafeMath: addition overflow");

        return c; 
    }

    function toUint256Safe(int256 a) internal pure returns (uint256) {
        require(a >= 0);
        return uint256(a);
  }
}


contract Halloween is Context, IERC20 {
    using SafeMath for uint256;
    using SignedSafeMath for int256;
    using Address for address;

    

    uint256 private _totalSupply;

    string private _name;
    string private _symbol;
    uint8 private _decimals;
    address private _owner;

    IERC20 public pumpkin;
    uint256 public totalPumpkinRewards;
    uint256 constant internal multiplier = 2**64;
    uint256 public pumpkinMultiple;
    uint256 public lastPumpkinBalance;
    address private pumpkinSetter;
    
	mapping(address => int256) public correctionPumpkin;
	mapping(address => uint256) public withdrawnPumpkin;
	
	mapping (address => uint256) private _balances;

    mapping (address => mapping (address => uint256)) private _allowances;
    
    event PumpkinWithdrawn(address indexed user, uint256 amount);
    event Transfer(address indexed from, address indexed to, uint256 value);
    event Approval(address indexed owner, address indexed spender, uint256 value);

    constructor () public {
        _name = "Halloween.finance";
        _symbol = "HALLOWEEN";
        _decimals = 18;
        pumpkinMultiple = multiplier;
        uint256 supply = 13000 ether;
        _mint(msg.sender, supply);
        pumpkinSetter = msg.sender;

    }

    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;
    }

    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);
        _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");
        require(amount >= 1000000, "ERC20: minimum transfer is 1.000.000 wei");
        updateHalloweenRewards();
        _balances[sender] = _balances[sender].sub(amount, "ERC20: transfer amount exceeds balance");
        _balances[recipient] = _balances[recipient].add(amount);
        		correctionPumpkin[sender] = correctionPumpkin[sender]
			.add( (pumpkinMultiple.mul(amount)).toInt256Safe() );
		correctionPumpkin[recipient] = correctionPumpkin[recipient]
			.sub( (pumpkinMultiple.mul(amount)).toInt256Safe() );
        emit Transfer(sender, recipient, 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 _mint(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: mint to the zero address");

        _totalSupply = _totalSupply.add(amount);
        _balances[account] = _balances[account].add(amount);
        correctionPumpkin[account] = correctionPumpkin[account]
			.sub( (pumpkinMultiple.mul(amount)).toInt256Safe() );
        emit Transfer(address(0), account, amount);
    }



    function setPumpkinAddress(address _pumpkinAddress) public {
        require(msg.sender == pumpkinSetter);
        pumpkin = IERC20(_pumpkinAddress);
    }
 
    function updateHalloweenRewards() internal {
        
        if( getBalancePumpkin() > lastPumpkinBalance) {
        uint256 difference = getBalancePumpkin().sub(lastPumpkinBalance);
		uint256 updateReward = difference.mul(multiplier).div(totalSupply());

		pumpkinMultiple = pumpkinMultiple.add(updateReward);
		}
    }
    
    function getBalancePumpkin() public view returns (uint256) {
		return pumpkin.balanceOf(address(this));
	}
	
	function getPumpkinReward() public {
	    
	    updateHalloweenRewards();
	    uint256 amount = withdrawablePumpkin(msg.sender);
	    withdrawnPumpkin[msg.sender] = withdrawnPumpkin[msg.sender].add(amount);
        totalPumpkinRewards = totalPumpkinRewards.add(amount);
	    require(pumpkin.transfer(msg.sender, amount));
	    lastPumpkinBalance = getBalancePumpkin();
	    emit PumpkinWithdrawn(msg.sender, amount);
	}

	function withdrawablePumpkin(address user) internal view returns(uint256) {
		return accumulativePumpkin(user).sub(withdrawnPumpkin[user]);
	}
	
	function accumulativePumpkin(address _user) internal view returns(uint256) {
		return (pumpkinMultiple.mul(balanceOf(_user)).toInt256Safe()
			.add(correctionPumpkin[_user]).toUint256Safe()).div(multiplier);
	}
	
}

{
  "compilationTarget": {
    "Halloween.sol": "Halloween"
  },
  "evmVersion": "istanbul",
  "libraries": {},
  "metadata": {
    "bytecodeHash": "ipfs"
  },
  "optimizer": {
    "enabled": false,
    "runs": 200
  },
  "remappings": []
}