pragma solidity ^0.4.24;

// File: zeppelin-solidity/contracts/math/SafeMath.sol

/**
 * @title SafeMath
 * @dev Math operations with safety checks that throw on error
 */
library SafeMath {
  function mul(uint256 a, uint256 b) internal constant returns (uint256) {
    uint256 c = a * b;
    assert(a == 0 || c / a == b);
    return c;
  }

  function div(uint256 a, uint256 b) internal constant 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 c;
  }

  function sub(uint256 a, uint256 b) internal constant returns (uint256) {
    assert(b <= a);
    return a - b;
  }

  function add(uint256 a, uint256 b) internal constant returns (uint256) {
    uint256 c = a + b;
    assert(c >= a);
    return c;
  }
}

// File: zeppelin-solidity/contracts/ownership/Ownable.sol

/**
 * @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() {
    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) onlyOwner public {
    require(newOwner != address(0));
    OwnershipTransferred(owner, newOwner);
    owner = newOwner;
  }

}

// File: zeppelin-solidity/contracts/lifecycle/Destructible.sol

/**
 * @title Destructible
 * @dev Base contract that can be destroyed by owner. All funds in contract will be sent to the owner.
 */
contract Destructible is Ownable {

  function Destructible() payable { }

  /**
   * @dev Transfers the current balance to the owner and terminates the contract.
   */
  function destroy() onlyOwner public {
    selfdestruct(owner);
  }

  function destroyAndSend(address _recipient) onlyOwner public {
    selfdestruct(_recipient);
  }
}

// File: zeppelin-solidity/contracts/lifecycle/Pausable.sol

/**
 * @title Pausable
 * @dev Base contract which allows children to implement an emergency stop mechanism.
 */
contract Pausable is Ownable {
  event Pause();
  event Unpause();

  bool public paused = false;


  /**
   * @dev Modifier to make a function callable only when the contract is not paused.
   */
  modifier whenNotPaused() {
    require(!paused);
    _;
  }

  /**
   * @dev Modifier to make a function callable only when the contract is paused.
   */
  modifier whenPaused() {
    require(paused);
    _;
  }

  /**
   * @dev called by the owner to pause, triggers stopped state
   */
  function pause() onlyOwner whenNotPaused public {
    paused = true;
    Pause();
  }

  /**
   * @dev called by the owner to unpause, returns to normal state
   */
  function unpause() onlyOwner whenPaused public {
    paused = false;
    Unpause();
  }
}

// File: zeppelin-solidity/contracts/ownership/Contactable.sol

/**
 * @title Contactable token
 * @dev Basic version of a contactable contract, allowing the owner to provide a string with their
 * contact information.
 */
contract Contactable is Ownable{

    string public contactInformation;

    /**
     * @dev Allows the owner to set a string with their contact information.
     * @param info The contact information to attach to the contract.
     */
    function setContactInformation(string info) onlyOwner public {
         contactInformation = info;
     }
}

// File: contracts/Restricted.sol

/** @title Restricted
 *  Exposes onlyMonetha modifier
 */
contract Restricted is Ownable {

    //MonethaAddress set event
    event MonethaAddressSet(
        address _address,
        bool _isMonethaAddress
    );

    mapping (address => bool) public isMonethaAddress;

    /**
     *  Restrict methods in such way, that they can be invoked only by monethaAddress account.
     */
    modifier onlyMonetha() {
        require(isMonethaAddress[msg.sender]);
        _;
    }

    /**
     *  Allows owner to set new monetha address
     */
    function setMonethaAddress(address _address, bool _isMonethaAddress) onlyOwner public {
        isMonethaAddress[_address] = _isMonethaAddress;

        MonethaAddressSet(_address, _isMonethaAddress);
    }
}

// File: contracts/ERC20.sol

/**
* @title ERC20 interface
*/
contract ERC20 {
    function totalSupply() public view returns (uint256);

    function decimals() public view returns(uint256);

    function balanceOf(address _who) public view returns (uint256);

    function allowance(address _owner, address _spender)
        public view returns (uint256);

    function transfer(address _to, uint256 _value) public returns (bool);

    function approve(address _spender, uint256 _value)
        public returns (bool);

    function transferFrom(address _from, address _to, uint256 _value)
        public returns (bool);

    event Transfer(
        address indexed from,
        address indexed to,
        uint256 value
    );

    event Approval(
        address indexed owner,
        address indexed spender,
        uint256 value
    );
}

// File: contracts/MonethaGateway.sol

/**
 *  @title MonethaGateway
 *
 *  MonethaGateway forward funds from order payment to merchant's wallet and collects Monetha fee.
 */
contract MonethaGateway is Pausable, Contactable, Destructible, Restricted {

    using SafeMath for uint256;
    
    string constant VERSION = "0.5";

    /**
     *  Fee permille of Monetha fee.
     *  1 permille (‰) = 0.1 percent (%)
     *  15‰ = 1.5%
     */
    uint public constant FEE_PERMILLE = 15;
    
    /**
     *  Address of Monetha Vault for fee collection
     */
    address public monethaVault;

    /**
     *  Account for permissions managing
     */
    address public admin;

    event PaymentProcessedEther(address merchantWallet, uint merchantIncome, uint monethaIncome);
    event PaymentProcessedToken(address tokenAddress, address merchantWallet, uint merchantIncome, uint monethaIncome);

    /**
     *  @param _monethaVault Address of Monetha Vault
     */
    constructor(address _monethaVault, address _admin) public {
        require(_monethaVault != 0x0);
        monethaVault = _monethaVault;
        
        setAdmin(_admin);
    }
    
    /**
     *  acceptPayment accept payment from PaymentAcceptor, forwards it to merchant's wallet
     *      and collects Monetha fee.
     *  @param _merchantWallet address of merchant's wallet for fund transfer
     *  @param _monethaFee is a fee collected by Monetha
     */
    function acceptPayment(address _merchantWallet, uint _monethaFee) external payable onlyMonetha whenNotPaused {
        require(_merchantWallet != 0x0);
        require(_monethaFee >= 0 && _monethaFee <= FEE_PERMILLE.mul(msg.value).div(1000)); // Monetha fee cannot be greater than 1.5% of payment
        
        uint merchantIncome = msg.value.sub(_monethaFee);

        _merchantWallet.transfer(merchantIncome);
        monethaVault.transfer(_monethaFee);

        emit PaymentProcessedEther(_merchantWallet, merchantIncome, _monethaFee);
    }

    /**
     *  acceptTokenPayment accept token payment from PaymentAcceptor, forwards it to merchant's wallet
     *      and collects Monetha fee.
     *  @param _merchantWallet address of merchant's wallet for fund transfer
     *  @param _monethaFee is a fee collected by Monetha
     *  @param _tokenAddress is the token address
     *  @param _value is the order value
     */
    function acceptTokenPayment(
        address _merchantWallet,
        uint _monethaFee,
        address _tokenAddress,
        uint _value
    )
        external onlyMonetha whenNotPaused
    {
        require(_merchantWallet != 0x0);

        // Monetha fee cannot be greater than 1.5% of payment
        require(_monethaFee >= 0 && _monethaFee <= FEE_PERMILLE.mul(_value).div(1000));

        uint merchantIncome = _value.sub(_monethaFee);
        
        ERC20(_tokenAddress).transfer(_merchantWallet, merchantIncome);
        ERC20(_tokenAddress).transfer(monethaVault, _monethaFee);
        
        emit PaymentProcessedToken(_tokenAddress, _merchantWallet, merchantIncome, _monethaFee);
    }

    /**
     *  changeMonethaVault allows owner to change address of Monetha Vault.
     *  @param newVault New address of Monetha Vault
     */
    function changeMonethaVault(address newVault) external onlyOwner whenNotPaused {
        monethaVault = newVault;
    }

    /**
     *  Allows other monetha account or contract to set new monetha address
     */
    function setMonethaAddress(address _address, bool _isMonethaAddress) public {
        require(msg.sender == admin || msg.sender == owner);

        isMonethaAddress[_address] = _isMonethaAddress;

        emit MonethaAddressSet(_address, _isMonethaAddress);
    }

    /**
     *  setAdmin allows owner to change address of admin.
     *  @param _admin New address of admin
     */
    function setAdmin(address _admin) public onlyOwner {
        require(_admin != 0x0);
        admin = _admin;
    }
}