// Vulnerability label: clean
pragma solidity ^0.4.23;


/**
 * @title SafeMath
 * @dev Math operations with safety checks that throw on error
 */
library SafeMath {

  /**
  * @dev Multiplies two numbers, throws on overflow.
  */
  function mul(uint256 a, uint256 b) internal pure returns (uint256 c) {
    if (a == 0) {
      return 0;
    }
    c = a * b;
    assert(c / a == b);
    return c;
  }

  /**
  * @dev Integer division of two numbers, truncating the quotient.
  */
  function div(uint256 a, uint256 b) internal pure returns (uint256) {
    // assert(b > 0); // Solidity automatically throws when dividing by 0
    // uint256 c = a / b;
    // assert(a == b * c + a % b); // There is no case in which this doesn't hold
    return a / b;
  }

  /**
  * @dev Subtracts two numbers, throws on overflow (i.e. if subtrahend is greater than minuend).
  */
  function sub(uint256 a, uint256 b) internal pure returns (uint256) {
    assert(b <= a);
    return a - b;
  }

  /**
  * @dev Adds two numbers, throws on overflow.
  */
  function add(uint256 a, uint256 b) internal pure returns (uint256 c) {
    c = a + b;
    assert(c >= a);
    return c;
  }
}

/**
 * @title ERC20Basic
 * @dev Simpler version of ERC20 interface
 * @dev see https://github.com/ethereum/EIPs/issues/179
 */
contract ERC20Basic {
  function totalSupply() public view returns (uint256);
  function balanceOf(address who) public view returns (uint256);
  function transfer(address to, uint256 value) public returns (bool);
  event Transfer(address indexed from, address indexed to, uint256 value);
}


/**
 * @title Basic token
 * @dev Basic version of StandardToken, with no allowances.
 */
contract BasicToken is ERC20Basic {
  using SafeMath for uint256;

  mapping(address => uint256) balances;

  uint256 totalSupply_;

  /**
  * @dev total number of tokens in existence
  */
  function totalSupply() public view returns (uint256) {
    return totalSupply_;
  }

  /**
  * @dev transfer token for a specified address
  * @param _to The address to transfer to.
  * @param _value The amount to be transferred.
  */
  function transfer(address _to, uint256 _value) public returns (bool) {
    require(_to != address(0));
    require(_value <= balances[msg.sender]);

    balances[msg.sender] = balances[msg.sender].sub(_value);
    balances[_to] = balances[_to].add(_value);
    emit Transfer(msg.sender, _to, _value);
    return true;
  }

  /**
  * @dev Gets the balance of the specified address.
  * @param _owner The address to query the the balance of.
  * @return An uint256 representing the amount owned by the passed address.
  */
  function balanceOf(address _owner) public view returns (uint256) {
    return balances[_owner];
  }

}

/**
 * @title ERC20 interface
 * @dev see https://github.com/ethereum/EIPs/issues/20
 */
contract ERC20 is ERC20Basic {
  function allowance(address owner, address spender) public view returns (uint256);
  function transferFrom(address from, address to, uint256 value) public returns (bool);
  function approve(address spender, uint256 value) public returns (bool);
  event Approval(address indexed owner, address indexed spender, uint256 value);
}


/**
 * @title Standard ERC20 token
 *
 * @dev Implementation of the basic standard token.
 * @dev https://github.com/ethereum/EIPs/issues/20
 * @dev Based on code by FirstBlood: https://github.com/Firstbloodio/token/blob/master/smart_contract/FirstBloodToken.sol
 */
contract StandardToken is ERC20, BasicToken {

  mapping (address => mapping (address => uint256)) internal allowed;


  /**
   * @dev Transfer tokens from one address to another
   * @param _from address The address which you want to send tokens from
   * @param _to address The address which you want to transfer to
   * @param _value uint256 the amount of tokens to be transferred
   */
  function transferFrom(address _from, address _to, uint256 _value) public returns (bool) {
    require(_to != address(0));
    require(_value <= balances[_from]);
    require(_value <= allowed[_from][msg.sender]);

    balances[_from] = balances[_from].sub(_value);
    balances[_to] = balances[_to].add(_value);
    allowed[_from][msg.sender] = allowed[_from][msg.sender].sub(_value);
    emit Transfer(_from, _to, _value);
    return true;
  }

  /**
   * @dev Approve the passed address to spend the specified amount of tokens on behalf of msg.sender.
   *
   * Beware that changing an allowance with this method brings the risk that someone may use both the old
   * and the new allowance by unfortunate transaction ordering. One possible solution to mitigate this
   * race condition is to first reduce the spender's allowance to 0 and set the desired value afterwards:
   * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
   * @param _spender The address which will spend the funds.
   * @param _value The amount of tokens to be spent.
   */
  function approve(address _spender, uint256 _value) public returns (bool) {
    allowed[msg.sender][_spender] = _value;
    emit Approval(msg.sender, _spender, _value);
    return true;
  }

  /**
   * @dev Function to check the amount of tokens that an owner allowed to a spender.
   * @param _owner address The address which owns the funds.
   * @param _spender address The address which will spend the funds.
   * @return A uint256 specifying the amount of tokens still available for the spender.
   */
  function allowance(address _owner, address _spender) public view returns (uint256) {
    return allowed[_owner][_spender];
  }

  /**
   * @dev Increase the amount of tokens that an owner allowed to a spender.
   *
   * approve should be called when allowed[_spender] == 0. To increment
   * allowed value is better to use this function to avoid 2 calls (and wait until
   * the first transaction is mined)
   * From MonolithDAO Token.sol
   * @param _spender The address which will spend the funds.
   * @param _addedValue The amount of tokens to increase the allowance by.
   */
  function increaseApproval(address _spender, uint _addedValue) public returns (bool) {
    allowed[msg.sender][_spender] = allowed[msg.sender][_spender].add(_addedValue);
    emit Approval(msg.sender, _spender, allowed[msg.sender][_spender]);
    return true;
  }

  /**
   * @dev Decrease the amount of tokens that an owner allowed to a spender.
   *
   * approve should be called when allowed[_spender] == 0. To decrement
   * allowed value is better to use this function to avoid 2 calls (and wait until
   * the first transaction is mined)
   * From MonolithDAO Token.sol
   * @param _spender The address which will spend the funds.
   * @param _subtractedValue The amount of tokens to decrease the allowance by.
   */
  function decreaseApproval(address _spender, uint _subtractedValue) public returns (bool) {
    uint oldValue = allowed[msg.sender][_spender];
    if (_subtractedValue > oldValue) {
      allowed[msg.sender][_spender] = 0;
    } else {
      allowed[msg.sender][_spender] = oldValue.sub(_subtractedValue);
    }
    emit Approval(msg.sender, _spender, allowed[msg.sender][_spender]);
    return true;
  }

}

/**
 * @title SimpleToken
 * @dev Very simple ERC20 Token example, where all tokens are pre-assigned to the creator.
 * Note they can later distribute these tokens as they wish using `transfer` and other
 * `StandardToken` functions.
 */
contract FIN is StandardToken {
  string public constant name = "Financial Incentive Network Points";
  string public constant symbol = "FIN";
  uint8 public constant decimals = 18; // solium-disable-line uppercase

  uint256 private constant OFFSET = 10 ** uint256(decimals);
  uint256 private constant BILLION = (10 ** 9) * OFFSET; // 1 billion is a 1 followed by 9 zeroes
  
  uint256 private TOTAL_SUPPLY;

  constructor(address _holderA, address _holderB, address _holderC) public {
    balances[_holderA] = BILLION;
    emit Transfer(0x0, _holderA, BILLION);

    balances[_holderB] = BILLION;
    emit Transfer(0x0, _holderB, BILLION);

    balances[_holderC] = BILLION / 2;
    emit Transfer(0x0, _holderC, BILLION / 2);
    
    TOTAL_SUPPLY = balances[_holderA] + balances[_holderB] + balances[_holderC];
  }
  
  function totalSupply() public view returns (uint256) {
      return TOTAL_SUPPLY;
  }
}


interface TokenValidator {
  function check(
    address _token,
    address _user
  ) external returns(byte result);

  function check(
    address _token,
    address _from,
    address _to,
    uint256 _amount
  ) external returns (byte result);
}


interface ValidatedToken {
  event Validation(
    byte    indexed result,
    address indexed user
  );

  event Validation(
    byte    indexed result,
    address indexed from,
    address indexed to,
    uint256         value
  );
}



/**
 * @title Ownable
 * @dev The Ownable contract has an owner address, and provides basic authorization control
 * functions, this simplifies the implementation of "user permissions".
 */
contract Ownable {
  address public owner;


  event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);


  /**
   * @dev The Ownable constructor sets the original `owner` of the contract to the sender
   * account.
   */
  function Ownable() public {
    owner = msg.sender;
  }

  /**
   * @dev Throws if called by any account other than the owner.
   */
  modifier onlyOwner() {
    require(msg.sender == owner);
    _;
  }

  /**
   * @dev Allows the current owner to transfer control of the contract to a newOwner.
   * @param newOwner The address to transfer ownership to.
   */
  function transferOwnership(address newOwner) public onlyOwner {
    require(newOwner != address(0));
    OwnershipTransferred(owner, newOwner);
    owner = newOwner;
  }

}


contract ReferenceToken is Ownable, ERC20, ValidatedToken {
    using SafeMath for uint256;

    string internal mName;
    string internal mSymbol;

    uint256 internal mGranularity;
    uint256 internal mTotalSupply;

    mapping(address => uint) internal mBalances;
    mapping(address => mapping(address => bool)) internal mAuthorized;
    mapping(address => mapping(address => uint256)) internal mAllowed;

    uint8 public decimals = 18;

    // Single validator
    TokenValidator internal validator;

    constructor(
        string         _name,
        string         _symbol,
        uint256        _granularity,
        TokenValidator _validator
    ) public {
        require(_granularity >= 1);

        mName = _name;
        mSymbol = _symbol;
        mTotalSupply = 0;
        mGranularity = _granularity;
        validator = TokenValidator(_validator);
    }

    // Validation Helpers

    function validate(address _user) internal returns (byte) {
        byte checkResult = validator.check(this, _user);
        emit Validation(checkResult, _user);
        return checkResult;
    }

    function validate(
        address _from,
        address _to,
        uint256 _amount
    ) internal returns (byte) {
        byte checkResult = validator.check(this, _from, _to, _amount);
        emit Validation(checkResult, _from, _to, _amount);
        return checkResult;
    }

    // Status Code Helpers

    function isOk(byte _statusCode) internal pure returns (bool) {
        return (_statusCode & hex"0F") == 1;
    }

    function requireOk(byte _statusCode) internal pure {
        require(isOk(_statusCode));
    }

    function name() public constant returns (string) {
        return mName;
    }

    function symbol() public constant returns(string) {
        return mSymbol;
    }

    function granularity() public constant returns(uint256) {
        return mGranularity;
    }

    function totalSupply() public constant returns(uint256) {
        return mTotalSupply;
    }

    function balanceOf(address _tokenHolder) public constant returns (uint256) {
        return mBalances[_tokenHolder];
    }

    function isMultiple(uint256 _amount) internal view returns (bool) {
      return _amount.div(mGranularity).mul(mGranularity) == _amount;
    }

    function approve(address _spender, uint256 _amount) public returns (bool success) {
        if(validate(msg.sender, _spender, _amount) != 1) { return false; }

        mAllowed[msg.sender][_spender] = _amount;
        emit Approval(msg.sender, _spender, _amount);
        return true;
    }

    function allowance(address _owner, address _spender) public constant returns (uint256 remaining) {
        return mAllowed[_owner][_spender];
    }

    function mint(address _tokenHolder, uint256 _amount) public onlyOwner {
        requireOk(validate(_tokenHolder));
        require(isMultiple(_amount));

        mTotalSupply = mTotalSupply.add(_amount);
        mBalances[_tokenHolder] = mBalances[_tokenHolder].add(_amount);

        emit Transfer(0x0, _tokenHolder, _amount);
    }

    function transfer(address _to, uint256 _amount) public returns (bool success) {
        doSend(msg.sender, _to, _amount);
        return true;
    }

    function transferFrom(address _from, address _to, uint256 _amount) public returns (bool success) {
        require(_amount <= mAllowed[_from][msg.sender]);

        mAllowed[_from][msg.sender] = mAllowed[_from][msg.sender].sub(_amount);
        doSend(_from, _to, _amount);
        return true;
    }

    function doSend(
        address _from,
        address _to,
        uint256 _amount
    ) internal {
        require(canTransfer(_from, _to, _amount));

        mBalances[_from] = mBalances[_from].sub(_amount);
        mBalances[_to] = mBalances[_to].add(_amount);

        emit Transfer(_from, _to, _amount);
    }

    function canTransfer(
        address _from,
        address _to,
        uint256 _amount
    ) internal returns (bool) {
        return (
            (_to != address(0)) // Forbid sending to 0x0 (=burning)
            && isMultiple(_amount)
            && (mBalances[_from] >= _amount) // Ensure enough funds
            && isOk(validate(_from, _to, _amount)) // Ensure passes validation
        );
    }
}


contract Lunar is ReferenceToken {
    uint256 constant DECIMAL_SHIFT = 10 ** 18;
    
    constructor(TokenValidator _validator)
      ReferenceToken("Lunar Token - SAMPLE NO VALUE", "LNRX", 1, _validator)
      public {
          uint256 supply = 5000000 * DECIMAL_SHIFT;

          mTotalSupply = supply;
          mBalances[msg.sender] = supply;

          emit Transfer(0x0, msg.sender, supply);
      }
}


contract SimpleAuthorization is TokenValidator, Ownable {
    mapping(address => bool) private auths;

    constructor() public {}

    function check(
        address /* token */,
        address _address
    ) external returns (byte resultCode) {
        if (auths[_address]) {
            return hex"11";
        } else {
            return hex"10";
        }
    }

    function check(
        address /* _token */,
        address _from,
        address _to,
        uint256 /* _amount */
    ) external returns (byte resultCode) {
        if (auths[_from] && auths[_to]) {
            return hex"11";
        } else {
            return hex"10";
        }
    }

    function setAuthorized(address _address, bool _status) public onlyOwner {
        auths[_address] = _status;
    }
}