pragma solidity ^0.4.11;

/**
 * @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;
    }
}

/**
 * @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;
    }

}

/**
 * @title RefundVault
 * @dev This contract is used for storing funds while a crowdsale
 * is in progress. Supports refunding the money if crowdsale fails,
 * and forwarding it if crowdsale is successful.
 */
contract RefundVault is Ownable {
    using SafeMath for uint256;

    enum State { Active, Refunding, Closed }

    mapping (address => uint256) public deposited;
    address public wallet;
    State public state;

    event Closed();
    event RefundsEnabled();
    event Refunded(address indexed beneficiary, uint256 weiAmount);

    function RefundVault(address _wallet) {
        require(_wallet != 0x0);
        wallet = _wallet;
        state = State.Active;
    }

    function deposit(address investor) onlyOwner public payable {
        require(state == State.Active);
        deposited[investor] = deposited[investor].add(msg.value);
    }

    function close() onlyOwner public {
        require(state == State.Active);
        state = State.Closed;
        Closed();
        wallet.transfer(this.balance);
    }

    function enableRefunds() onlyOwner public {
        require(state == State.Active);
        state = State.Refunding;
        RefundsEnabled();
    }

    function refund(address investor) public {
        require(state == State.Refunding);
        uint256 depositedValue = deposited[investor];
        deposited[investor] = 0;
        investor.transfer(depositedValue);
        Refunded(investor, depositedValue);
    }
}


/**
 * @title ERC20Basic
 * @dev Simpler version of ERC20 interface
 * @dev see https://github.com/ethereum/EIPs/issues/179
 */
contract ERC20Basic {
    uint256 public totalSupply;
    function balanceOf(address who) constant returns (uint256);
    function transfer(address to, uint256 value) returns (bool);
    event Transfer(address indexed from, address indexed to, uint256 value);
}


/**
 * @title ERC20 interface
 * @dev see https://github.com/ethereum/EIPs/issues/20
 */
contract ERC20 is ERC20Basic {
    function allowance(address owner, address spender) constant returns (uint256);
    function transferFrom(address from, address to, uint256 value) returns (bool);
    function approve(address spender, uint256 value) returns (bool);
    event Approval(address indexed owner, address indexed spender, 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;

    /**
    * @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) returns (bool) {
        balances[msg.sender] = balances[msg.sender].sub(_value);
        balances[_to] = balances[_to].add(_value);
        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) constant returns (uint256 balance) {
        return balances[_owner];
    }

}

/**
 * @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);
        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;
        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 constant returns (uint256 remaining) {
        return allowed[_owner][_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
     */
    function increaseApproval (address _spender, uint _addedValue) public returns (bool success) {
        allowed[msg.sender][_spender] = allowed[msg.sender][_spender].add(_addedValue);
        Approval(msg.sender, _spender, allowed[msg.sender][_spender]);
        return true;
    }

    function decreaseApproval (address _spender, uint _subtractedValue) public returns (bool success) {
        uint oldValue = allowed[msg.sender][_spender];
        if (_subtractedValue > oldValue) {
            allowed[msg.sender][_spender] = 0;
        } else {
            allowed[msg.sender][_spender] = oldValue.sub(_subtractedValue);
        }
        Approval(msg.sender, _spender, allowed[msg.sender][_spender]);
        return true;
    }

}

/**
 * @title Mintable token
 * @dev Simple ERC20 Token example, with mintable token creation
 * @dev Issue: * https://github.com/OpenZeppelin/zeppelin-solidity/issues/120
 * Based on code by TokenMarketNet: https://github.com/TokenMarketNet/ico/blob/master/contracts/MintableToken.sol
 */

contract MintableToken is StandardToken, Ownable {
    event Mint(address indexed to, uint256 amount);
    event MintFinished();

    bool public mintingFinished = false;


    modifier canMint() {
        require(!mintingFinished);
        _;
    }

    /**
     * @dev Function to mint tokens
     * @param _to The address that will receive the minted tokens.
     * @param _amount The amount of tokens to mint.
     * @return A boolean that indicates if the operation was successful.
     */
    function mint(address _to, uint256 _amount) onlyOwner canMint public returns (bool) {
        totalSupply = totalSupply.add(_amount);
        balances[_to] = balances[_to].add(_amount);
        Mint(_to, _amount);
        Transfer(0x0, _to, _amount);
        return true;
    }

    /**
     * @dev Function to stop minting new tokens.
     * @return True if the operation was successful.
     */
    function finishMinting() onlyOwner public returns (bool) {
        mintingFinished = true;
        MintFinished();
        return true;
    }
}

// Standard token variables
contract TokenOfGratitude is MintableToken {
    string constant public name = "Token Of Gratitude";
    string constant public symbol = "ToG";
    uint8 constant public decimals = 0;

    uint256 public expirationDate = 1672531199;
    address public goldenTicketOwner;

    // Mappings for easier backchecking
    mapping (address => uint) redeemed;

    // ToG redeem event with encrypted message (hopefully a contact info)
    event tokenRedemption(address indexed supported, string message);

    // Golden ticket related events
    event goldenTicketMoved(address indexed newOwner);
    event goldenTicketUsed(address charlie, string message);

    function TokenOfGratitude() {
        goldenTicketOwner = msg.sender;
    }

    /**
     * Function returning the current price of ToG
     * @dev can be used prior to the donation as a constant function but it is mainly used in the noname function
     * @param message should contain an encrypted contract info of the redeemer to setup a meeting
     */
    function redeem(string message) {

        // Check caller has a token
        require (balances[msg.sender] >= 1);

        // Check tokens did not expire
        require (now <= expirationDate);

        // Lock the token against further transfers
        balances[msg.sender] -= 1;
        redeemed[msg.sender] += 1;

        // Call out
        tokenRedemption(msg.sender, message);
    }

    /**
     * Function using the Golden ticket - the current holder will be able to get the prize only based on the "goldenTicketUsed" event
     * @dev First checks the GT owner, then fires the event and then changes the owner to null so GT can't be used again
     * @param message should contain an encrypted contract info of the redeemer to claim the reward
     */
    function useGoldenTicket(string message){
        require(msg.sender == goldenTicketOwner);
        goldenTicketUsed(msg.sender, message);
        goldenTicketOwner = 0x0;
    }

    /**
     * Function using the Golden ticket - the current holder will be able to get the prize only based on the "goldenTicketUsed" event
     * @dev First checks the GT owner, then change the owner and fire an event about the ticket changing owner
     * @dev The Golden ticket isn't a standard ERC20 token and therefore it needs special handling
     * @param newOwner should be a valid address of the new owner
     */
    function giveGoldenTicket(address newOwner) {
        require (msg.sender == goldenTicketOwner);
        goldenTicketOwner = newOwner;
        goldenTicketMoved(newOwner);
    }

}

// <ORACLIZE_API>
/*
Copyright (c) 2015-2016 Oraclize SRL
Copyright (c) 2016 Oraclize LTD



Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:



The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.



THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
*/

pragma solidity ^0.4.0;//please import oraclizeAPI_pre0.4.sol when solidity < 0.4.0

contract OraclizeI {
    address public cbAddress;
    function query(uint _timestamp, string _datasource, string _arg) payable returns (bytes32 _id);
    function query_withGasLimit(uint _timestamp, string _datasource, string _arg, uint _gaslimit) payable returns (bytes32 _id);
    function query2(uint _timestamp, string _datasource, string _arg1, string _arg2) payable returns (bytes32 _id);
    function query2_withGasLimit(uint _timestamp, string _datasource, string _arg1, string _arg2, uint _gaslimit) payable returns (bytes32 _id);
    function queryN(uint _timestamp, string _datasource, bytes _argN) payable returns (bytes32 _id);
    function queryN_withGasLimit(uint _timestamp, string _datasource, bytes _argN, uint _gaslimit) payable returns (bytes32 _id);
    function getPrice(string _datasource) returns (uint _dsprice);
    function getPrice(string _datasource, uint gaslimit) returns (uint _dsprice);
    function useCoupon(string _coupon);
    function setProofType(byte _proofType);
    function setConfig(bytes32 _config);
    function setCustomGasPrice(uint _gasPrice);
    function randomDS_getSessionPubKeyHash() returns(bytes32);
}
contract OraclizeAddrResolverI {
    function getAddress() returns (address _addr);
}
contract usingOraclize {
    uint constant day = 60*60*24;
    uint constant week = 60*60*24*7;
    uint constant month = 60*60*24*30;
    byte constant proofType_NONE = 0x00;
    byte constant proofType_TLSNotary = 0x10;
    byte constant proofType_Android = 0x20;
    byte constant proofType_Ledger = 0x30;
    byte constant proofType_Native = 0xF0;
    byte constant proofStorage_IPFS = 0x01;
    uint8 constant networkID_auto = 0;
    uint8 constant networkID_mainnet = 1;
    uint8 constant networkID_testnet = 2;
    uint8 constant networkID_morden = 2;
    uint8 constant networkID_consensys = 161;

    OraclizeAddrResolverI OAR;

    OraclizeI oraclize;
    modifier oraclizeAPI {
        if((address(OAR)==0)||(getCodeSize(address(OAR))==0))
        oraclize_setNetwork(networkID_auto);

        if(address(oraclize) != OAR.getAddress())
        oraclize = OraclizeI(OAR.getAddress());

        _;
    }
    modifier coupon(string code){
        oraclize = OraclizeI(OAR.getAddress());
        oraclize.useCoupon(code);
        _;
    }

    function oraclize_setNetwork(uint8 networkID) internal returns(bool){
        if (getCodeSize(0x1d3B2638a7cC9f2CB3D298A3DA7a90B67E5506ed)>0){ //mainnet
            OAR = OraclizeAddrResolverI(0x1d3B2638a7cC9f2CB3D298A3DA7a90B67E5506ed);
            oraclize_setNetworkName("eth_mainnet");
            return true;
        }
        if (getCodeSize(0xc03A2615D5efaf5F49F60B7BB6583eaec212fdf1)>0){ //ropsten testnet
            OAR = OraclizeAddrResolverI(0xc03A2615D5efaf5F49F60B7BB6583eaec212fdf1);
            oraclize_setNetworkName("eth_ropsten3");
            return true;
        }
        if (getCodeSize(0xB7A07BcF2Ba2f2703b24C0691b5278999C59AC7e)>0){ //kovan testnet
            OAR = OraclizeAddrResolverI(0xB7A07BcF2Ba2f2703b24C0691b5278999C59AC7e);
            oraclize_setNetworkName("eth_kovan");
            return true;
        }
        if (getCodeSize(0x146500cfd35B22E4A392Fe0aDc06De1a1368Ed48)>0){ //rinkeby testnet
            OAR = OraclizeAddrResolverI(0x146500cfd35B22E4A392Fe0aDc06De1a1368Ed48);
            oraclize_setNetworkName("eth_rinkeby");
            return true;
        }
        if (getCodeSize(0x6f485C8BF6fc43eA212E93BBF8ce046C7f1cb475)>0){ //ethereum-bridge
            OAR = OraclizeAddrResolverI(0x6f485C8BF6fc43eA212E93BBF8ce046C7f1cb475);
            return true;
        }
        if (getCodeSize(0x20e12A1F859B3FeaE5Fb2A0A32C18F5a65555bBF)>0){ //ether.camp ide
            OAR = OraclizeAddrResolverI(0x20e12A1F859B3FeaE5Fb2A0A32C18F5a65555bBF);
            return true;
        }
        if (getCodeSize(0x51efaF4c8B3C9AfBD5aB9F4bbC82784Ab6ef8fAA)>0){ //browser-solidity
            OAR = OraclizeAddrResolverI(0x51efaF4c8B3C9AfBD5aB9F4bbC82784Ab6ef8fAA);
            return true;
        }
        return false;
    }

    function __callback(bytes32 myid, string result) {
        __callback(myid, result, new bytes(0));
    }
    function __callback(bytes32 myid, string result, bytes proof) {
    }

    function oraclize_useCoupon(string code) oraclizeAPI internal {
        oraclize.useCoupon(code);
    }

    function oraclize_getPrice(string datasource) oraclizeAPI internal returns (uint){
        return oraclize.getPrice(datasource);
    }

    function oraclize_getPrice(string datasource, uint gaslimit) oraclizeAPI internal returns (uint){
        return oraclize.getPrice(datasource, gaslimit);
    }

    function oraclize_query(string datasource, string arg) oraclizeAPI internal returns (bytes32 id){
        uint price = oraclize.getPrice(datasource);
        if (price > 1 ether + tx.gasprice*200000) return 0; // unexpectedly high price
        return oraclize.query.value(price)(0, datasource, arg);
    }
    function oraclize_query(uint timestamp, string datasource, string arg) oraclizeAPI internal returns (bytes32 id){
        uint price = oraclize.getPrice(datasource);
        if (price > 1 ether + tx.gasprice*200000) return 0; // unexpectedly high price
        return oraclize.query.value(price)(timestamp, datasource, arg);
    }
    function oraclize_query(uint timestamp, string datasource, string arg, uint gaslimit) oraclizeAPI internal returns (bytes32 id){
        uint price = oraclize.getPrice(datasource, gaslimit);
        if (price > 1 ether + tx.gasprice*gaslimit) return 0; // unexpectedly high price
        return oraclize.query_withGasLimit.value(price)(timestamp, datasource, arg, gaslimit);
    }
    function oraclize_query(string datasource, string arg, uint gaslimit) oraclizeAPI internal returns (bytes32 id){
        uint price = oraclize.getPrice(datasource, gaslimit);
        if (price > 1 ether + tx.gasprice*gaslimit) return 0; // unexpectedly high price
        return oraclize.query_withGasLimit.value(price)(0, datasource, arg, gaslimit);
    }
    function oraclize_query(string datasource, string arg1, string arg2) oraclizeAPI internal returns (bytes32 id){
        uint price = oraclize.getPrice(datasource);
        if (price > 1 ether + tx.gasprice*200000) return 0; // unexpectedly high price
        return oraclize.query2.value(price)(0, datasource, arg1, arg2);
    }
    function oraclize_query(uint timestamp, string datasource, string arg1, string arg2) oraclizeAPI internal returns (bytes32 id){
        uint price = oraclize.getPrice(datasource);
        if (price > 1 ether + tx.gasprice*200000) return 0; // unexpectedly high price
        return oraclize.query2.value(price)(timestamp, datasource, arg1, arg2);
    }
    function oraclize_query(uint timestamp, string datasource, string arg1, string arg2, uint gaslimit) oraclizeAPI internal returns (bytes32 id){
        uint price = oraclize.getPrice(datasource, gaslimit);
        if (price > 1 ether + tx.gasprice*gaslimit) return 0; // unexpectedly high price
        return oraclize.query2_withGasLimit.value(price)(timestamp, datasource, arg1, arg2, gaslimit);
    }
    function oraclize_query(string datasource, string arg1, string arg2, uint gaslimit) oraclizeAPI internal returns (bytes32 id){
        uint price = oraclize.getPrice(datasource, gaslimit);
        if (price > 1 ether + tx.gasprice*gaslimit) return 0; // unexpectedly high price
        return oraclize.query2_withGasLimit.value(price)(0, datasource, arg1, arg2, gaslimit);
    }
    function oraclize_query(string datasource, string[] argN) oraclizeAPI internal returns (bytes32 id){
        uint price = oraclize.getPrice(datasource);
        if (price > 1 ether + tx.gasprice*200000) return 0; // unexpectedly high price
        bytes memory args = stra2cbor(argN);
        return oraclize.queryN.value(price)(0, datasource, args);
    }
    function oraclize_query(uint timestamp, string datasource, string[] argN) oraclizeAPI internal returns (bytes32 id){
        uint price = oraclize.getPrice(datasource);
        if (price > 1 ether + tx.gasprice*200000) return 0; // unexpectedly high price
        bytes memory args = stra2cbor(argN);
        return oraclize.queryN.value(price)(timestamp, datasource, args);
    }
    function oraclize_query(uint timestamp, string datasource, string[] argN, uint gaslimit) oraclizeAPI internal returns (bytes32 id){
        uint price = oraclize.getPrice(datasource, gaslimit);
        if (price > 1 ether + tx.gasprice*gaslimit) return 0; // unexpectedly high price
        bytes memory args = stra2cbor(argN);
        return oraclize.queryN_withGasLimit.value(price)(timestamp, datasource, args, gaslimit);
    }
    function oraclize_query(string datasource, string[] argN, uint gaslimit) oraclizeAPI internal returns (bytes32 id){
        uint price = oraclize.getPrice(datasource, gaslimit);
        if (price > 1 ether + tx.gasprice*gaslimit) return 0; // unexpectedly high price
        bytes memory args = stra2cbor(argN);
        return oraclize.queryN_withGasLimit.value(price)(0, datasource, args, gaslimit);
    }
    function oraclize_query(string datasource, string[1] args) oraclizeAPI internal returns (bytes32 id) {
        string[] memory dynargs = new string[](1);
        dynargs[0] = args[0];
        return oraclize_query(datasource, dynargs);
    }
    function oraclize_query(uint timestamp, string datasource, string[1] args) oraclizeAPI internal returns (bytes32 id) {
        string[] memory dynargs = new string[](1);
        dynargs[0] = args[0];
        return oraclize_query(timestamp, datasource, dynargs);
    }
    function oraclize_query(uint timestamp, string datasource, string[1] args, uint gaslimit) oraclizeAPI internal returns (bytes32 id) {
        string[] memory dynargs = new string[](1);
        dynargs[0] = args[0];
        return oraclize_query(timestamp, datasource, dynargs, gaslimit);
    }
    function oraclize_query(string datasource, string[1] args, uint gaslimit) oraclizeAPI internal returns (bytes32 id) {
        string[] memory dynargs = new string[](1);
        dynargs[0] = args[0];
        return oraclize_query(datasource, dynargs, gaslimit);
    }

    function oraclize_query(string datasource, string[2] args) oraclizeAPI internal returns (bytes32 id) {
        string[] memory dynargs = new string[](2);
        dynargs[0] = args[0];
        dynargs[1] = args[1];
        return oraclize_query(datasource, dynargs);
    }
    function oraclize_query(uint timestamp, string datasource, string[2] args) oraclizeAPI internal returns (bytes32 id) {
        string[] memory dynargs = new string[](2);
        dynargs[0] = args[0];
        dynargs[1] = args[1];
        return oraclize_query(timestamp, datasource, dynargs);
    }
    function oraclize_query(uint timestamp, string datasource, string[2] args, uint gaslimit) oraclizeAPI internal returns (bytes32 id) {
        string[] memory dynargs = new string[](2);
        dynargs[0] = args[0];
        dynargs[1] = args[1];
        return oraclize_query(timestamp, datasource, dynargs, gaslimit);
    }
    function oraclize_query(string datasource, string[2] args, uint gaslimit) oraclizeAPI internal returns (bytes32 id) {
        string[] memory dynargs = new string[](2);
        dynargs[0] = args[0];
        dynargs[1] = args[1];
        return oraclize_query(datasource, dynargs, gaslimit);
    }
    function oraclize_query(string datasource, string[3] args) oraclizeAPI internal returns (bytes32 id) {
        string[] memory dynargs = new string[](3);
        dynargs[0] = args[0];
        dynargs[1] = args[1];
        dynargs[2] = args[2];
        return oraclize_query(datasource, dynargs);
    }
    function oraclize_query(uint timestamp, string datasource, string[3] args) oraclizeAPI internal returns (bytes32 id) {
        string[] memory dynargs = new string[](3);
        dynargs[0] = args[0];
        dynargs[1] = args[1];
        dynargs[2] = args[2];
        return oraclize_query(timestamp, datasource, dynargs);
    }
    function oraclize_query(uint timestamp, string datasource, string[3] args, uint gaslimit) oraclizeAPI internal returns (bytes32 id) {
        string[] memory dynargs = new string[](3);
        dynargs[0] = args[0];
        dynargs[1] = args[1];
        dynargs[2] = args[2];
        return oraclize_query(timestamp, datasource, dynargs, gaslimit);
    }
    function oraclize_query(string datasource, string[3] args, uint gaslimit) oraclizeAPI internal returns (bytes32 id) {
        string[] memory dynargs = new string[](3);
        dynargs[0] = args[0];
        dynargs[1] = args[1];
        dynargs[2] = args[2];
        return oraclize_query(datasource, dynargs, gaslimit);
    }

    function oraclize_query(string datasource, string[4] args) oraclizeAPI internal returns (bytes32 id) {
        string[] memory dynargs = new string[](4);
        dynargs[0] = args[0];
        dynargs[1] = args[1];
        dynargs[2] = args[2];
        dynargs[3] = args[3];
        return oraclize_query(datasource, dynargs);
    }
    function oraclize_query(uint timestamp, string datasource, string[4] args) oraclizeAPI internal returns (bytes32 id) {
        string[] memory dynargs = new string[](4);
        dynargs[0] = args[0];
        dynargs[1] = args[1];
        dynargs[2] = args[2];
        dynargs[3] = args[3];
        return oraclize_query(timestamp, datasource, dynargs);
    }
    function oraclize_query(uint timestamp, string datasource, string[4] args, uint gaslimit) oraclizeAPI internal returns (bytes32 id) {
        string[] memory dynargs = new string[](4);
        dynargs[0] = args[0];
        dynargs[1] = args[1];
        dynargs[2] = args[2];
        dynargs[3] = args[3];
        return oraclize_query(timestamp, datasource, dynargs, gaslimit);
    }
    function oraclize_query(string datasource, string[4] args, uint gaslimit) oraclizeAPI internal returns (bytes32 id) {
        string[] memory dynargs = new string[](4);
        dynargs[0] = args[0];
        dynargs[1] = args[1];
        dynargs[2] = args[2];
        dynargs[3] = args[3];
        return oraclize_query(datasource, dynargs, gaslimit);
    }
    function oraclize_query(string datasource, string[5] args) oraclizeAPI internal returns (bytes32 id) {
        string[] memory dynargs = new string[](5);
        dynargs[0] = args[0];
        dynargs[1] = args[1];
        dynargs[2] = args[2];
        dynargs[3] = args[3];
        dynargs[4] = args[4];
        return oraclize_query(datasource, dynargs);
    }
    function oraclize_query(uint timestamp, string datasource, string[5] args) oraclizeAPI internal returns (bytes32 id) {
        string[] memory dynargs = new string[](5);
        dynargs[0] = args[0];
        dynargs[1] = args[1];
        dynargs[2] = args[2];
        dynargs[3] = args[3];
        dynargs[4] = args[4];
        return oraclize_query(timestamp, datasource, dynargs);
    }
    function oraclize_query(uint timestamp, string datasource, string[5] args, uint gaslimit) oraclizeAPI internal returns (bytes32 id) {
        string[] memory dynargs = new string[](5);
        dynargs[0] = args[0];
        dynargs[1] = args[1];
        dynargs[2] = args[2];
        dynargs[3] = args[3];
        dynargs[4] = args[4];
        return oraclize_query(timestamp, datasource, dynargs, gaslimit);
    }
    function oraclize_query(string datasource, string[5] args, uint gaslimit) oraclizeAPI internal returns (bytes32 id) {
        string[] memory dynargs = new string[](5);
        dynargs[0] = args[0];
        dynargs[1] = args[1];
        dynargs[2] = args[2];
        dynargs[3] = args[3];
        dynargs[4] = args[4];
        return oraclize_query(datasource, dynargs, gaslimit);
    }
    function oraclize_query(string datasource, bytes[] argN) oraclizeAPI internal returns (bytes32 id){
        uint price = oraclize.getPrice(datasource);
        if (price > 1 ether + tx.gasprice*200000) return 0; // unexpectedly high price
        bytes memory args = ba2cbor(argN);
        return oraclize.queryN.value(price)(0, datasource, args);
    }
    function oraclize_query(uint timestamp, string datasource, bytes[] argN) oraclizeAPI internal returns (bytes32 id){
        uint price = oraclize.getPrice(datasource);
        if (price > 1 ether + tx.gasprice*200000) return 0; // unexpectedly high price
        bytes memory args = ba2cbor(argN);
        return oraclize.queryN.value(price)(timestamp, datasource, args);
    }
    function oraclize_query(uint timestamp, string datasource, bytes[] argN, uint gaslimit) oraclizeAPI internal returns (bytes32 id){
        uint price = oraclize.getPrice(datasource, gaslimit);
        if (price > 1 ether + tx.gasprice*gaslimit) return 0; // unexpectedly high price
        bytes memory args = ba2cbor(argN);
        return oraclize.queryN_withGasLimit.value(price)(timestamp, datasource, args, gaslimit);
    }
    function oraclize_query(string datasource, bytes[] argN, uint gaslimit) oraclizeAPI internal returns (bytes32 id){
        uint price = oraclize.getPrice(datasource, gaslimit);
        if (price > 1 ether + tx.gasprice*gaslimit) return 0; // unexpectedly high price
        bytes memory args = ba2cbor(argN);
        return oraclize.queryN_withGasLimit.value(price)(0, datasource, args, gaslimit);
    }
    function oraclize_query(string datasource, bytes[1] args) oraclizeAPI internal returns (bytes32 id) {
        bytes[] memory dynargs = new bytes[](1);
        dynargs[0] = args[0];
        return oraclize_query(datasource, dynargs);
    }
    function oraclize_query(uint timestamp, string datasource, bytes[1] args) oraclizeAPI internal returns (bytes32 id) {
        bytes[] memory dynargs = new bytes[](1);
        dynargs[0] = args[0];
        return oraclize_query(timestamp, datasource, dynargs);
    }
    function oraclize_query(uint timestamp, string datasource, bytes[1] args, uint gaslimit) oraclizeAPI internal returns (bytes32 id) {
        bytes[] memory dynargs = new bytes[](1);
        dynargs[0] = args[0];
        return oraclize_query(timestamp, datasource, dynargs, gaslimit);
    }
    function oraclize_query(string datasource, bytes[1] args, uint gaslimit) oraclizeAPI internal returns (bytes32 id) {
        bytes[] memory dynargs = new bytes[](1);
        dynargs[0] = args[0];
        return oraclize_query(datasource, dynargs, gaslimit);
    }

    function oraclize_query(string datasource, bytes[2] args) oraclizeAPI internal returns (bytes32 id) {
        bytes[] memory dynargs = new bytes[](2);
        dynargs[0] = args[0];
        dynargs[1] = args[1];
        return oraclize_query(datasource, dynargs);
    }
    function oraclize_query(uint timestamp, string datasource, bytes[2] args) oraclizeAPI internal returns (bytes32 id) {
        bytes[] memory dynargs = new bytes[](2);
        dynargs[0] = args[0];
        dynargs[1] = args[1];
        return oraclize_query(timestamp, datasource, dynargs);
    }
    function oraclize_query(uint timestamp, string datasource, bytes[2] args, uint gaslimit) oraclizeAPI internal returns (bytes32 id) {
        bytes[] memory dynargs = new bytes[](2);
        dynargs[0] = args[0];
        dynargs[1] = args[1];
        return oraclize_query(timestamp, datasource, dynargs, gaslimit);
    }
    function oraclize_query(string datasource, bytes[2] args, uint gaslimit) oraclizeAPI internal returns (bytes32 id) {
        bytes[] memory dynargs = new bytes[](2);
        dynargs[0] = args[0];
        dynargs[1] = args[1];
        return oraclize_query(datasource, dynargs, gaslimit);
    }
    function oraclize_query(string datasource, bytes[3] args) oraclizeAPI internal returns (bytes32 id) {
        bytes[] memory dynargs = new bytes[](3);
        dynargs[0] = args[0];
        dynargs[1] = args[1];
        dynargs[2] = args[2];
        return oraclize_query(datasource, dynargs);
    }
    function oraclize_query(uint timestamp, string datasource, bytes[3] args) oraclizeAPI internal returns (bytes32 id) {
        bytes[] memory dynargs = new bytes[](3);
        dynargs[0] = args[0];
        dynargs[1] = args[1];
        dynargs[2] = args[2];
        return oraclize_query(timestamp, datasource, dynargs);
    }
    function oraclize_query(uint timestamp, string datasource, bytes[3] args, uint gaslimit) oraclizeAPI internal returns (bytes32 id) {
        bytes[] memory dynargs = new bytes[](3);
        dynargs[0] = args[0];
        dynargs[1] = args[1];
        dynargs[2] = args[2];
        return oraclize_query(timestamp, datasource, dynargs, gaslimit);
    }
    function oraclize_query(string datasource, bytes[3] args, uint gaslimit) oraclizeAPI internal returns (bytes32 id) {
        bytes[] memory dynargs = new bytes[](3);
        dynargs[0] = args[0];
        dynargs[1] = args[1];
        dynargs[2] = args[2];
        return oraclize_query(datasource, dynargs, gaslimit);
    }

    function oraclize_query(string datasource, bytes[4] args) oraclizeAPI internal returns (bytes32 id) {
        bytes[] memory dynargs = new bytes[](4);
        dynargs[0] = args[0];
        dynargs[1] = args[1];
        dynargs[2] = args[2];
        dynargs[3] = args[3];
        return oraclize_query(datasource, dynargs);
    }
    function oraclize_query(uint timestamp, string datasource, bytes[4] args) oraclizeAPI internal returns (bytes32 id) {
        bytes[] memory dynargs = new bytes[](4);
        dynargs[0] = args[0];
        dynargs[1] = args[1];
        dynargs[2] = args[2];
        dynargs[3] = args[3];
        return oraclize_query(timestamp, datasource, dynargs);
    }
    function oraclize_query(uint timestamp, string datasource, bytes[4] args, uint gaslimit) oraclizeAPI internal returns (bytes32 id) {
        bytes[] memory dynargs = new bytes[](4);
        dynargs[0] = args[0];
        dynargs[1] = args[1];
        dynargs[2] = args[2];
        dynargs[3] = args[3];
        return oraclize_query(timestamp, datasource, dynargs, gaslimit);
    }
    function oraclize_query(string datasource, bytes[4] args, uint gaslimit) oraclizeAPI internal returns (bytes32 id) {
        bytes[] memory dynargs = new bytes[](4);
        dynargs[0] = args[0];
        dynargs[1] = args[1];
        dynargs[2] = args[2];
        dynargs[3] = args[3];
        return oraclize_query(datasource, dynargs, gaslimit);
    }
    function oraclize_query(string datasource, bytes[5] args) oraclizeAPI internal returns (bytes32 id) {
        bytes[] memory dynargs = new bytes[](5);
        dynargs[0] = args[0];
        dynargs[1] = args[1];
        dynargs[2] = args[2];
        dynargs[3] = args[3];
        dynargs[4] = args[4];
        return oraclize_query(datasource, dynargs);
    }
    function oraclize_query(uint timestamp, string datasource, bytes[5] args) oraclizeAPI internal returns (bytes32 id) {
        bytes[] memory dynargs = new bytes[](5);
        dynargs[0] = args[0];
        dynargs[1] = args[1];
        dynargs[2] = args[2];
        dynargs[3] = args[3];
        dynargs[4] = args[4];
        return oraclize_query(timestamp, datasource, dynargs);
    }
    function oraclize_query(uint timestamp, string datasource, bytes[5] args, uint gaslimit) oraclizeAPI internal returns (bytes32 id) {
        bytes[] memory dynargs = new bytes[](5);
        dynargs[0] = args[0];
        dynargs[1] = args[1];
        dynargs[2] = args[2];
        dynargs[3] = args[3];
        dynargs[4] = args[4];
        return oraclize_query(timestamp, datasource, dynargs, gaslimit);
    }
    function oraclize_query(string datasource, bytes[5] args, uint gaslimit) oraclizeAPI internal returns (bytes32 id) {
        bytes[] memory dynargs = new bytes[](5);
        dynargs[0] = args[0];
        dynargs[1] = args[1];
        dynargs[2] = args[2];
        dynargs[3] = args[3];
        dynargs[4] = args[4];
        return oraclize_query(datasource, dynargs, gaslimit);
    }

    function oraclize_cbAddress() oraclizeAPI internal returns (address){
        return oraclize.cbAddress();
    }
    function oraclize_setProof(byte proofP) oraclizeAPI internal {
        return oraclize.setProofType(proofP);
    }
    function oraclize_setCustomGasPrice(uint gasPrice) oraclizeAPI internal {
        return oraclize.setCustomGasPrice(gasPrice);
    }
    function oraclize_setConfig(bytes32 config) oraclizeAPI internal {
        return oraclize.setConfig(config);
    }

    function oraclize_randomDS_getSessionPubKeyHash() oraclizeAPI internal returns (bytes32){
        return oraclize.randomDS_getSessionPubKeyHash();
    }

    function getCodeSize(address _addr) constant internal returns(uint _size) {
        assembly {
        _size := extcodesize(_addr)
        }
    }

    function parseAddr(string _a) internal returns (address){
        bytes memory tmp = bytes(_a);
        uint160 iaddr = 0;
        uint160 b1;
        uint160 b2;
        for (uint i=2; i<2+2*20; i+=2){
            iaddr *= 256;
            b1 = uint160(tmp[i]);
            b2 = uint160(tmp[i+1]);
            if ((b1 >= 97)&&(b1 <= 102)) b1 -= 87;
            else if ((b1 >= 65)&&(b1 <= 70)) b1 -= 55;
            else if ((b1 >= 48)&&(b1 <= 57)) b1 -= 48;
            if ((b2 >= 97)&&(b2 <= 102)) b2 -= 87;
            else if ((b2 >= 65)&&(b2 <= 70)) b2 -= 55;
            else if ((b2 >= 48)&&(b2 <= 57)) b2 -= 48;
            iaddr += (b1*16+b2);
        }
        return address(iaddr);
    }

    function strCompare(string _a, string _b) internal returns (int) {
        bytes memory a = bytes(_a);
        bytes memory b = bytes(_b);
        uint minLength = a.length;
        if (b.length < minLength) minLength = b.length;
        for (uint i = 0; i < minLength; i ++)
        if (a[i] < b[i])
        return -1;
        else if (a[i] > b[i])
        return 1;
        if (a.length < b.length)
        return -1;
        else if (a.length > b.length)
        return 1;
        else
        return 0;
    }

    function indexOf(string _haystack, string _needle) internal returns (int) {
        bytes memory h = bytes(_haystack);
        bytes memory n = bytes(_needle);
        if(h.length < 1 || n.length < 1 || (n.length > h.length))
        return -1;
        else if(h.length > (2**128 -1))
        return -1;
        else
        {
            uint subindex = 0;
            for (uint i = 0; i < h.length; i ++)
            {
                if (h[i] == n[0])
                {
                    subindex = 1;
                    while(subindex < n.length && (i + subindex) < h.length && h[i + subindex] == n[subindex])
                    {
                        subindex++;
                    }
                    if(subindex == n.length)
                    return int(i);
                }
            }
            return -1;
        }
    }

    function strConcat(string _a, string _b, string _c, string _d, string _e) internal returns (string) {
        bytes memory _ba = bytes(_a);
        bytes memory _bb = bytes(_b);
        bytes memory _bc = bytes(_c);
        bytes memory _bd = bytes(_d);
        bytes memory _be = bytes(_e);
        string memory abcde = new string(_ba.length + _bb.length + _bc.length + _bd.length + _be.length);
        bytes memory babcde = bytes(abcde);
        uint k = 0;
        for (uint i = 0; i < _ba.length; i++) babcde[k++] = _ba[i];
        for (i = 0; i < _bb.length; i++) babcde[k++] = _bb[i];
        for (i = 0; i < _bc.length; i++) babcde[k++] = _bc[i];
        for (i = 0; i < _bd.length; i++) babcde[k++] = _bd[i];
        for (i = 0; i < _be.length; i++) babcde[k++] = _be[i];
        return string(babcde);
    }

    function strConcat(string _a, string _b, string _c, string _d) internal returns (string) {
        return strConcat(_a, _b, _c, _d, "");
    }

    function strConcat(string _a, string _b, string _c) internal returns (string) {
        return strConcat(_a, _b, _c, "", "");
    }

    function strConcat(string _a, string _b) internal returns (string) {
        return strConcat(_a, _b, "", "", "");
    }

    // parseInt
    function parseInt(string _a) internal returns (uint) {
        return parseInt(_a, 0);
    }

    // parseInt(parseFloat*10^_b)
    function parseInt(string _a, uint _b) internal returns (uint) {
        bytes memory bresult = bytes(_a);
        uint mint = 0;
        bool decimals = false;
        for (uint i=0; i<bresult.length; i++){
            if ((bresult[i] >= 48)&&(bresult[i] <= 57)){
                if (decimals){
                    if (_b == 0) break;
                    else _b--;
                }
                mint *= 10;
                mint += uint(bresult[i]) - 48;
            } else if (bresult[i] == 46) decimals = true;
        }
        if (_b > 0) mint *= 10**_b;
        return mint;
    }

    function uint2str(uint i) internal returns (string){
        if (i == 0) return "0";
        uint j = i;
        uint len;
        while (j != 0){
            len++;
            j /= 10;
        }
        bytes memory bstr = new bytes(len);
        uint k = len - 1;
        while (i != 0){
            bstr[k--] = byte(48 + i % 10);
            i /= 10;
        }
        return string(bstr);
    }

    function stra2cbor(string[] arr) internal returns (bytes) {
        uint arrlen = arr.length;

        // get correct cbor output length
        uint outputlen = 0;
        bytes[] memory elemArray = new bytes[](arrlen);
        for (uint i = 0; i < arrlen; i++) {
            elemArray[i] = (bytes(arr[i]));
            outputlen += elemArray[i].length + (elemArray[i].length - 1)/23 + 3; //+3 accounts for paired identifier types
        }
        uint ctr = 0;
        uint cborlen = arrlen + 0x80;
        outputlen += byte(cborlen).length;
        bytes memory res = new bytes(outputlen);

        while (byte(cborlen).length > ctr) {
            res[ctr] = byte(cborlen)[ctr];
            ctr++;
        }
        for (i = 0; i < arrlen; i++) {
            res[ctr] = 0x5F;
            ctr++;
            for (uint x = 0; x < elemArray[i].length; x++) {
                // if there's a bug with larger strings, this may be the culprit
                if (x % 23 == 0) {
                    uint elemcborlen = elemArray[i].length - x >= 24 ? 23 : elemArray[i].length - x;
                    elemcborlen += 0x40;
                    uint lctr = ctr;
                    while (byte(elemcborlen).length > ctr - lctr) {
                        res[ctr] = byte(elemcborlen)[ctr - lctr];
                        ctr++;
                    }
                }
                res[ctr] = elemArray[i][x];
                ctr++;
            }
            res[ctr] = 0xFF;
            ctr++;
        }
        return res;
    }

    function ba2cbor(bytes[] arr) internal returns (bytes) {
        uint arrlen = arr.length;

        // get correct cbor output length
        uint outputlen = 0;
        bytes[] memory elemArray = new bytes[](arrlen);
        for (uint i = 0; i < arrlen; i++) {
            elemArray[i] = (bytes(arr[i]));
            outputlen += elemArray[i].length + (elemArray[i].length - 1)/23 + 3; //+3 accounts for paired identifier types
        }
        uint ctr = 0;
        uint cborlen = arrlen + 0x80;
        outputlen += byte(cborlen).length;
        bytes memory res = new bytes(outputlen);

        while (byte(cborlen).length > ctr) {
            res[ctr] = byte(cborlen)[ctr];
            ctr++;
        }
        for (i = 0; i < arrlen; i++) {
            res[ctr] = 0x5F;
            ctr++;
            for (uint x = 0; x < elemArray[i].length; x++) {
                // if there's a bug with larger strings, this may be the culprit
                if (x % 23 == 0) {
                    uint elemcborlen = elemArray[i].length - x >= 24 ? 23 : elemArray[i].length - x;
                    elemcborlen += 0x40;
                    uint lctr = ctr;
                    while (byte(elemcborlen).length > ctr - lctr) {
                        res[ctr] = byte(elemcborlen)[ctr - lctr];
                        ctr++;
                    }
                }
                res[ctr] = elemArray[i][x];
                ctr++;
            }
            res[ctr] = 0xFF;
            ctr++;
        }
        return res;
    }


    string oraclize_network_name;
    function oraclize_setNetworkName(string _network_name) internal {
        oraclize_network_name = _network_name;
    }

    function oraclize_getNetworkName() internal returns (string) {
        return oraclize_network_name;
    }

    function oraclize_newRandomDSQuery(uint _delay, uint _nbytes, uint _customGasLimit) internal returns (bytes32){
        if ((_nbytes == 0)||(_nbytes > 32)) throw;
        bytes memory nbytes = new bytes(1);
        nbytes[0] = byte(_nbytes);
        bytes memory unonce = new bytes(32);
        bytes memory sessionKeyHash = new bytes(32);
        bytes32 sessionKeyHash_bytes32 = oraclize_randomDS_getSessionPubKeyHash();
        assembly {
        mstore(unonce, 0x20)
        mstore(add(unonce, 0x20), xor(blockhash(sub(number, 1)), xor(coinbase, timestamp)))
        mstore(sessionKeyHash, 0x20)
        mstore(add(sessionKeyHash, 0x20), sessionKeyHash_bytes32)
        }
        bytes[3] memory args = [unonce, nbytes, sessionKeyHash];
        bytes32 queryId = oraclize_query(_delay, "random", args, _customGasLimit);
        oraclize_randomDS_setCommitment(queryId, sha3(bytes8(_delay), args[1], sha256(args[0]), args[2]));
        return queryId;
    }

    function oraclize_randomDS_setCommitment(bytes32 queryId, bytes32 commitment) internal {
        oraclize_randomDS_args[queryId] = commitment;
    }

    mapping(bytes32=>bytes32) oraclize_randomDS_args;
    mapping(bytes32=>bool) oraclize_randomDS_sessionKeysHashVerified;

    function verifySig(bytes32 tosignh, bytes dersig, bytes pubkey) internal returns (bool){
        bool sigok;
        address signer;

        bytes32 sigr;
        bytes32 sigs;

        bytes memory sigr_ = new bytes(32);
        uint offset = 4+(uint(dersig[3]) - 0x20);
        sigr_ = copyBytes(dersig, offset, 32, sigr_, 0);
        bytes memory sigs_ = new bytes(32);
        offset += 32 + 2;
        sigs_ = copyBytes(dersig, offset+(uint(dersig[offset-1]) - 0x20), 32, sigs_, 0);

        assembly {
        sigr := mload(add(sigr_, 32))
        sigs := mload(add(sigs_, 32))
        }


        (sigok, signer) = safer_ecrecover(tosignh, 27, sigr, sigs);
        if (address(sha3(pubkey)) == signer) return true;
        else {
            (sigok, signer) = safer_ecrecover(tosignh, 28, sigr, sigs);
            return (address(sha3(pubkey)) == signer);
        }
    }

    function oraclize_randomDS_proofVerify__sessionKeyValidity(bytes proof, uint sig2offset) internal returns (bool) {
        bool sigok;

        // Step 6: verify the attestation signature, APPKEY1 must sign the sessionKey from the correct ledger app (CODEHASH)
        bytes memory sig2 = new bytes(uint(proof[sig2offset+1])+2);
        copyBytes(proof, sig2offset, sig2.length, sig2, 0);

        bytes memory appkey1_pubkey = new bytes(64);
        copyBytes(proof, 3+1, 64, appkey1_pubkey, 0);

        bytes memory tosign2 = new bytes(1+65+32);
        tosign2[0] = 1; //role
        copyBytes(proof, sig2offset-65, 65, tosign2, 1);
        bytes memory CODEHASH = hex"fd94fa71bc0ba10d39d464d0d8f465efeef0a2764e3887fcc9df41ded20f505c";
        copyBytes(CODEHASH, 0, 32, tosign2, 1+65);
        sigok = verifySig(sha256(tosign2), sig2, appkey1_pubkey);

        if (sigok == false) return false;


        // Step 7: verify the APPKEY1 provenance (must be signed by Ledger)
        bytes memory LEDGERKEY = hex"7fb956469c5c9b89840d55b43537e66a98dd4811ea0a27224272c2e5622911e8537a2f8e86a46baec82864e98dd01e9ccc2f8bc5dfc9cbe5a91a290498dd96e4";

        bytes memory tosign3 = new bytes(1+65);
        tosign3[0] = 0xFE;
        copyBytes(proof, 3, 65, tosign3, 1);

        bytes memory sig3 = new bytes(uint(proof[3+65+1])+2);
        copyBytes(proof, 3+65, sig3.length, sig3, 0);

        sigok = verifySig(sha256(tosign3), sig3, LEDGERKEY);

        return sigok;
    }

    modifier oraclize_randomDS_proofVerify(bytes32 _queryId, string _result, bytes _proof) {
        // Step 1: the prefix has to match 'LP\x01' (Ledger Proof version 1)
        if ((_proof[0] != "L")||(_proof[1] != "P")||(_proof[2] != 1)) throw;

        bool proofVerified = oraclize_randomDS_proofVerify__main(_proof, _queryId, bytes(_result), oraclize_getNetworkName());
        if (proofVerified == false) throw;

        _;
    }

    function oraclize_randomDS_proofVerify__returnCode(bytes32 _queryId, string _result, bytes _proof) internal returns (uint8){
        // Step 1: the prefix has to match 'LP\x01' (Ledger Proof version 1)
        if ((_proof[0] != "L")||(_proof[1] != "P")||(_proof[2] != 1)) return 1;

        bool proofVerified = oraclize_randomDS_proofVerify__main(_proof, _queryId, bytes(_result), oraclize_getNetworkName());
        if (proofVerified == false) return 2;

        return 0;
    }

    function matchBytes32Prefix(bytes32 content, bytes prefix) internal returns (bool){
        bool match_ = true;

        for (var i=0; i<prefix.length; i++){
            if (content[i] != prefix[i]) match_ = false;
        }

        return match_;
    }

    function oraclize_randomDS_proofVerify__main(bytes proof, bytes32 queryId, bytes result, string context_name) internal returns (bool){
        bool checkok;


        // Step 2: the unique keyhash has to match with the sha256 of (context name + queryId)
        uint ledgerProofLength = 3+65+(uint(proof[3+65+1])+2)+32;
        bytes memory keyhash = new bytes(32);
        copyBytes(proof, ledgerProofLength, 32, keyhash, 0);
        checkok = (sha3(keyhash) == sha3(sha256(context_name, queryId)));
        if (checkok == false) return false;

        bytes memory sig1 = new bytes(uint(proof[ledgerProofLength+(32+8+1+32)+1])+2);
        copyBytes(proof, ledgerProofLength+(32+8+1+32), sig1.length, sig1, 0);


        // Step 3: we assume sig1 is valid (it will be verified during step 5) and we verify if 'result' is the prefix of sha256(sig1)
        checkok = matchBytes32Prefix(sha256(sig1), result);
        if (checkok == false) return false;


        // Step 4: commitment match verification, sha3(delay, nbytes, unonce, sessionKeyHash) == commitment in storage.
        // This is to verify that the computed args match with the ones specified in the query.
        bytes memory commitmentSlice1 = new bytes(8+1+32);
        copyBytes(proof, ledgerProofLength+32, 8+1+32, commitmentSlice1, 0);

        bytes memory sessionPubkey = new bytes(64);
        uint sig2offset = ledgerProofLength+32+(8+1+32)+sig1.length+65;
        copyBytes(proof, sig2offset-64, 64, sessionPubkey, 0);

        bytes32 sessionPubkeyHash = sha256(sessionPubkey);
        if (oraclize_randomDS_args[queryId] == sha3(commitmentSlice1, sessionPubkeyHash)){ //unonce, nbytes and sessionKeyHash match
            delete oraclize_randomDS_args[queryId];
        } else return false;


        // Step 5: validity verification for sig1 (keyhash and args signed with the sessionKey)
        bytes memory tosign1 = new bytes(32+8+1+32);
        copyBytes(proof, ledgerProofLength, 32+8+1+32, tosign1, 0);
        checkok = verifySig(sha256(tosign1), sig1, sessionPubkey);
        if (checkok == false) return false;

        // verify if sessionPubkeyHash was verified already, if not.. let's do it!
        if (oraclize_randomDS_sessionKeysHashVerified[sessionPubkeyHash] == false){
            oraclize_randomDS_sessionKeysHashVerified[sessionPubkeyHash] = oraclize_randomDS_proofVerify__sessionKeyValidity(proof, sig2offset);
        }

        return oraclize_randomDS_sessionKeysHashVerified[sessionPubkeyHash];
    }


    // the following function has been written by Alex Beregszaszi (@axic), use it under the terms of the MIT license
    function copyBytes(bytes from, uint fromOffset, uint length, bytes to, uint toOffset) internal returns (bytes) {
        uint minLength = length + toOffset;

        if (to.length < minLength) {
            // Buffer too small
            throw; // Should be a better way?
        }

        // NOTE: the offset 32 is added to skip the `size` field of both bytes variables
        uint i = 32 + fromOffset;
        uint j = 32 + toOffset;

        while (i < (32 + fromOffset + length)) {
            assembly {
            let tmp := mload(add(from, i))
            mstore(add(to, j), tmp)
            }
            i += 32;
            j += 32;
        }

        return to;
    }

    // the following function has been written by Alex Beregszaszi (@axic), use it under the terms of the MIT license
    // Duplicate Solidity's ecrecover, but catching the CALL return value
    function safer_ecrecover(bytes32 hash, uint8 v, bytes32 r, bytes32 s) internal returns (bool, address) {
        // We do our own memory management here. Solidity uses memory offset
        // 0x40 to store the current end of memory. We write past it (as
        // writes are memory extensions), but don't update the offset so
        // Solidity will reuse it. The memory used here is only needed for
        // this context.

        // FIXME: inline assembly can't access return values
        bool ret;
        address addr;

        assembly {
        let size := mload(0x40)
        mstore(size, hash)
        mstore(add(size, 32), v)
        mstore(add(size, 64), r)
        mstore(add(size, 96), s)

        // NOTE: we can reuse the request memory because we deal with
        //       the return code
        ret := call(3000, 1, 0, size, 128, size, 32)
        addr := mload(size)
        }

        return (ret, addr);
    }

    // the following function has been written by Alex Beregszaszi (@axic), use it under the terms of the MIT license
    function ecrecovery(bytes32 hash, bytes sig) internal returns (bool, address) {
        bytes32 r;
        bytes32 s;
        uint8 v;

        if (sig.length != 65)
        return (false, 0);

        // The signature format is a compact form of:
        //   {bytes32 r}{bytes32 s}{uint8 v}
        // Compact means, uint8 is not padded to 32 bytes.
        assembly {
        r := mload(add(sig, 32))
        s := mload(add(sig, 64))

        // Here we are loading the last 32 bytes. We exploit the fact that
        // 'mload' will pad with zeroes if we overread.
        // There is no 'mload8' to do this, but that would be nicer.
        v := byte(0, mload(add(sig, 96)))

        // Alternative solution:
        // 'byte' is not working due to the Solidity parser, so lets
        // use the second best option, 'and'
        // v := and(mload(add(sig, 65)), 255)
        }

        // albeit non-transactional signatures are not specified by the YP, one would expect it
        // to match the YP range of [27, 28]
        //
        // geth uses [0, 1] and some clients have followed. This might change, see:
        //  https://github.com/ethereum/go-ethereum/issues/2053
        if (v < 27)
        v += 27;

        if (v != 27 && v != 28)
        return (false, 0);

        return safer_ecrecover(hash, v, r, s);
    }

}
// </ORACLIZE_API>

/**
 * @title Crowdsale
 * @dev Crowdsale is a base contract for managing a token crowdsale.
 * Crowdsales have a start and end timestamps, where investors can make
 * token purchases and the crowdsale will assign them tokens based
 * on a token per ETH rate. Funds collected are forwarded to a wallet
 * as they arrive.
 */
contract Crowdsale {
    using SafeMath for uint256;

    // The token being sold
    TokenOfGratitude public token;

    // start and end timestamps where investments are allowed (both inclusive)
    uint256 public startTime;
    uint256 public endTime;

    // address where funds are collected
    //address public wallet; => funds are collected in this contract

    // amount of raised money in wei
    uint256 public weiRaised;

    /**
     * event for token purchase logging
     * @param purchaser who paid for the tokens
     * @param beneficiary who got the tokens
     * @param value weis paid for purchase
     * @param amount amount of tokens purchased
     */
    event TokenPurchase(address indexed purchaser, address indexed beneficiary, uint256 value, uint256 amount);


    function Crowdsale(uint256 _startTime, uint256 _endTime) {
        require(_startTime >= now);
        require(_endTime >= _startTime);

        token = createTokenContract();
        startTime = _startTime;
        endTime = _endTime;
    }

    // creates the token to be sold.
    // override this method to have crowdsale of a specific mintable token.
    function createTokenContract() internal returns (TokenOfGratitude) {
        return new TokenOfGratitude();
    }
    // fallback function can be used to buy tokens
    function () payable {
        buyTokens(msg.sender);
    }

    // low level token purchase function
    function buyTokens(address beneficiary) public payable {}


    // @return true if the transaction can buy tokens
    function validPurchase() internal constant returns (bool) {
        bool withinPeriod = now >= startTime && now <= endTime;
        bool nonZeroPurchase = msg.value != 0;
        return withinPeriod && nonZeroPurchase;
    }

    // @return true if crowdsale event has ended
    function hasEnded() public constant returns (bool) {
        return now > endTime;
    }


}

/**
 * @title FinalizableCrowdsale
 * @dev Extension of Crowdsale where an owner can do extra work
 * after finishing.
 */
contract FinalizableCrowdsale is Crowdsale, Ownable {
    using SafeMath for uint256;

    bool public isFinalized = false;

    event Finalized();

    /**
     * @dev Must be called after crowdsale ends, to do some extra finalization
     * work. Calls the contract's finalization function.
     */
    function finalize() onlyOwner public {
        require(!isFinalized);
        require(hasEnded());

        finalization();
        Finalized();

        isFinalized = true;
    }

    /**
     * @dev Can be overridden to add finalization logic. The overriding function
     * should call super.finalization() to ensure the chain of finalization is
     * executed entirely.
     */
    function finalization() internal {
    }
}

/**
 * @title Token of Gratitude fundraiser
 */
contract GratitudeCrowdsale is FinalizableCrowdsale, usingOraclize {

    // Utility variables
    uint256 public tokensLeft;

    // Defining helper variables to differentiate Oraclize queries
    bytes32 qID1;
    bytes32 qID2;


    // Rate related variables
    uint256 public rate;
    bool public hasRate;
    uint public rateAge;

    /*
     * Randomly chosen number for the meal invitation winner
     * @dev each supporter gets a nonce - the luckyNumber is randomly picked nonce by Oraclize
     * @dev then points to donorsList[luckyNumber] mapping to get the address of the winner
     */
    bool public hasRandom;
    uint256 luckyNumber;

    /*
     * Medicines sans frontiers (MSF) | Doctors without borders - the public donation address
     * @dev please check for due diligence:
     * @notice Link to English site: https://www.lekari-bez-hranic.cz/en/bank-details#cryptocurrencies
     * @notice Link to Czech site: https://www.lekari-bez-hranic.cz/bankovni-spojeni#kryptomeny
     * @notice Link to Etherscan: https://etherscan.io/address/0x249f02676d09a41938309447fda33fb533d91dfc
     */
    address constant public addressOfMSF = 0x249F02676D09A41938309447fdA33FB533d91DFC;
    address constant public communityAddress = 0x008e9392ef82edBA2c45f2B02B9A21ac6B599BCA;


    // Mapping of supporters for random selection
    uint256 public donors = 0;
    mapping (address => bool) donated;
    mapping (uint256 => address) donorsList;


    // Fundraising finalization events
    event finishFundraiser(uint raised);
    event fundsToMSF(uint value);
    event fundsToCommunity(uint value);

    // Special events for a very special golden ticket!
    event goldenTicketFound(address winner);

    // Oraclize related events
    event newOraclizeQuery(string description);
    event newRate(string price);
    event newRandom(string price);

    /**
     * Constructor
     * @dev Contract constructor
     * @param _startTime uint256 is a unix timestamp of when the fundraiser starts
     * @param _endTime uint256 is a unix timestamp of when the fundraiser ends
     */
    function GratitudeCrowdsale(uint256 _startTime, uint256 _endTime)
    FinalizableCrowdsale()
    Crowdsale(_startTime, _endTime)
    {
        owner = msg.sender;
        tokensLeft = 500;
    }

    /**
     * buyTokens override
     * @dev Implementation of the override to the buy in function for incoming ETH
     * @param beneficiary address of the participating party
     */
    function buyTokens(address beneficiary) public payable {
        require(beneficiary != 0x0);
        require(validPurchase());

        // Sign up first-time donors to the list + give them a nonce so they can win the golden ticket!
        if (!donated[beneficiary]) {
            donated[beneficiary] = true;
            donorsList[donors] = beneficiary;
            donors += 1;
        }

        // Check if there are still tokens left (otherwise skipped)
        if (tokensLeft > 0) {

            // See how many tokens can the donor get.
            uint256 toGet = howMany(msg.value);

            // If some, give the tokens to the donor.
            if (toGet > 0) {
                token.mint(beneficiary,toGet);
                TokenPurchase(msg.sender, beneficiary, msg.value, toGet);
            }
        }

        // update state
        weiRaised = weiRaised.add(msg.value);
    }

    /**
    * Recursive function that counts amount of tokens to assign (even if a contribution overflows certain price range)
    * @dev Recalculating tokens to receive based on teh currentPrice(2) function.
    * @dev Number of recursive entrances is equal to the number of price levels (not counting the initial call)
    * @return toGet - amount of tokens to receive from the particular price range
    */
    function howMany(uint256 _value) internal returns (uint256){

        // Check current price level
        var (price, canGet) =  currentPrice();
        uint256 toGet = _value.div(price);

        // Act based on amount of tokens to get
        if (canGet == 0) {
            toGet = 0;
        } else if (toGet > canGet) {
            tokensLeft -= canGet;
            toGet = canGet + howMany(_value - (canGet*price));
        } else {
            tokensLeft -= toGet;
        }
        return toGet;
    }

    /**
     * Function returning the current price of ToG and amount of tokens available at that price
     * @dev can be used prior to the donation as a constant function but it is mainly used in the noname function
     * @return price - current price range
     * @return maxAtPrice - maximal amount of tokens available at current price
     */
    function currentPrice() constant returns (uint256 price, uint256 maxAtPrice){

        if (tokensLeft > 400) {
            return (100 finney, tokensLeft - 400);
        } else if (tokensLeft > 300) {
            return (200 finney, tokensLeft - 300);
        } else if (tokensLeft > 200) {
            return (300 finney, tokensLeft - 200);
        } else if (tokensLeft > 100) {
            return (400 finney, tokensLeft - 100);
        } else {
            return (500 finney, tokensLeft);
        }
    }

    /**
     * The pre-finalization requirement - get ETHUSD rate
     * @dev initiates Oraclize call for ETHUSD rate
     * @param gasLimit uint256 setting gasLimit of the __callback tx from Oraclize
     */
    function loadRate(uint256 gasLimit) payable {
        // Owner check
        require(msg.sender == owner);

        // Make an Oraclize queriey for ETHUSD rate
        getRateUSD(gasLimit);
    }

    /**
     * The pre-finalization requirement - get Random number
     * @dev initiates Oraclize call for random number
     * @param gasLimit uint256 setting gasLimit of the __callback tx from Oraclize
     */
    function loadRandom(uint256 gasLimit) payable {
        // Owner check
        require(msg.sender == owner);

        // Make an Oraclize query for a random number
        getRandom(gasLimit);
    }

    /**
     * The finalization override - commented bellow
     */
    function finalization() internal {
        //Check if the crowdsale has ended
        require(hasEnded());

        // Check the rate was queried less then 1 hour ago
        require(hasRate);
        require((now - rateAge) <= 3600);

        // Check the random number was received
        require(hasRandom);

        // Assign GoldenTicket
        token.giveGoldenTicket(donorsList[luckyNumber]);
        goldenTicketFound(donorsList[luckyNumber]);

        // Calling checkResult from PriceChecker contract
        uint256 funding = checkResult();
        uint256 raisedWei = this.balance;
        uint256 charityShare;
        uint256 toCharity;

        // If goal isn't met => send everything to MSF
        if (funding < 10000) {
            addressOfMSF.transfer(raisedWei);
            fundsToMSF(toCharity);
        } else if (funding < 25000) {

            // If 2nd goal isn't met => send the rest above the 1st goal to MSF
            charityShare = toPercentage(funding, funding-10000);
            toCharity = fromPercentage(raisedWei, charityShare);

            // Donate to charity first
            addressOfMSF.transfer(toCharity);
            fundsToMSF(toCharity);

            // Send funds to community;
            communityAddress.transfer(raisedWei - toCharity);
            fundsToCommunity(raisedWei - toCharity);
        } else {

            // If 2nd goal is met => send the rest above the 2nd goal to MSF
            charityShare = toPercentage(funding, funding-25000);
            toCharity = fromPercentage(raisedWei, charityShare);

            // Donate to charity first
            addressOfMSF.transfer(toCharity);
            fundsToMSF(toCharity);

            // Send funds to community;
            communityAddress.transfer(raisedWei - toCharity);
            fundsToCommunity(raisedWei - toCharity);
        }
        token.finishMinting();
        super.finalization();
    }

    /**
     * @dev Checking results of the fundraiser in USD
     * @return rated - total funds raised converted to USD
     */
    function checkResult() internal returns (uint256){
        uint256 raised = this.balance;
        // convert wei => usd to perform checks
        uint256 rated = (raised.mul(rate)).div(10000000000000000000000);
        return rated;
    }

    /**
     * Helper function to get split funds between the community and charity I
     * @dev Counts percentage of the total funds that belongs to the charity
     * @param total funds raised in USD
     * @param part of the total funds raised that should go to the charity
     * @return percentage in full expressed as a natural number between 0 and 100
     */
    function toPercentage (uint256 total, uint256 part) internal returns (uint256) {
        return (part*100)/total;
    }

    /**
     * Helper function to get split funds between the community and charity II
     * @dev Counts the exact amount of Wei to get send to the charity
     * @param value of total funds raised in Wei
     * @param percentage to be used obtained from the toPercentage(2) function
     * @return amount of Wei to be send to the charity
     */
    function fromPercentage(uint256 value, uint256 percentage) internal returns (uint256) {
        return (value*percentage)/100;
    }

    // <DATA FEEDS USING ORACLIZE>

    /**
     * @dev Create the ETHUSD query to Kraken thorough Oraclize
     */
    function getRateUSD(uint256 _gasLimit) internal {

        //require(msg.sender == owner);
        oraclize_setProof(proofType_TLSNotary);
        if (oraclize.getPrice("URL") > this.balance) {
            newOraclizeQuery("Oraclize: Insufficient funds!");
        } else {
            newOraclizeQuery("Oraclize was asked for ETHUSD rate.");
            qID1 = oraclize_query("URL", "json(https://api.kraken.com/0/public/Ticker?pair=ETHUSD).result.XETHZUSD.p.1", _gasLimit);
        }
    }

    /**
     * @dev Create the random number query to Oraclize
     */
    function getRandom(uint256 _gasLimit) internal {

        //require (msg.sender == owner);
        oraclize_setProof(proofType_Ledger);
        if (oraclize.getPrice("random") > this.balance) {
            newOraclizeQuery("Oraclize: Insufficient funds!");
        } else {
            newOraclizeQuery("Oraclize was asked for a random number.");

            // Make query for 4 random bytes to potentially get a number between 0 and 4294967295.
            // The assumption is that there won't be more then 4294967295 participants.
            // This may potentially hurt your contract as the "random mod participants" result distribution is unequal.
            // There creates an incentive to join earlier to have an micro advantage.
            qID2 = oraclize_newRandomDSQuery(0, 4, _gasLimit);
        }
    }

    /**
     *Oraclize callback function awaiting for response from the queries
     * @dev uses qType to handle the last called query type
     * @dev different querytypes shouldn't be called before callback was received
     * @dev -> not implementing a query que as "owner" is the only party responsible for creating order
     */
    function __callback(bytes32 myid, string result, bytes proof) {
        require(msg.sender == oraclize_cbAddress());

        if (myid == qID1) {
            checkQueryA(myid, result, proof);
        } else if (myid == qID2) {
            checkQueryB(myid, result, proof);
        }
    }

    /**
     * A helper function to separate reaction to different Oraclize queries - ETHUSD rate
     * @dev reaction to ETHUSD rate oraclize callback - getRateUSD()
     * @dev sets global vars rate to the result and rateAge to current timeStamp
     * @param _myid 32 bytes identifying the query generated by Oraclize
     * @param _result string with query result by Oraclize
     * @param _proof byte array with the proof of source by Oraclize
     */
    function checkQueryA(bytes32 _myid, string _result, bytes _proof) internal {
        newRate(_result);

        // calling Oraclize string => uint256 converter for a number with 4 decimals
        rate = parseInt(_result,4);
        rateAge = now;
        hasRate = true;
    }

    /**
     * A helper function to separate reaction to different Oraclize queries - random number
     * @dev reaction to random number oraclize callback - getRandom(number of participants)
     * @dev sets global var luckyNumber to the result
     * @param _myid 32 bytes identifying the query generated by Oraclize
     * @param _result string with query result by Oraclize
     * @param _proof byte array with the proof of source by Oraclize
     */
    function checkQueryB(bytes32 _myid, string _result, bytes _proof) internal oraclize_randomDS_proofVerify(_myid, _result, _proof) {
        newRandom(_result);

        // Calling Oraclize string => uint converter
        uint256 someNumber = parseInt(string(bytes(_result)),0);

        // Getting a luckyNumber between 0 and the number of donors (Random-number modulo number of donors)
        luckyNumber = someNumber%donors;
        hasRandom = true;
    }

    //Adjusting the hasEnded function to a case where all tokens were sold
    function hasEnded() public constant returns (bool) {
        return ((now > endTime) || (tokensLeft <= 0)) ;
    }

}