// File: Address.sol



pragma solidity ^0.5.2;

/**
 * Utility library of inline functions on addresses
 */
library Address {
    /**
     * Returns whether the target address is a contract
     * @dev This function will return false if invoked during the constructor of a contract,
     * as the code is not actually created until after the constructor finishes.
     * @param account address of the account to check
     * @return whether the target address is a contract
     */
    function isContract(address account) internal view returns (bool) {
        uint256 size;
        // XXX Currently there is no better way to check if there is a contract in an address
        // than to check the size of the code at that address.
        // See https://ethereum.stackexchange.com/a/14016/36603
        // for more details about how this works.
        // TODO Check this again before the Serenity release, because all addresses will be
        // contracts then.
        // solhint-disable-next-line no-inline-assembly
        assembly { size := extcodesize(account) }
        return size > 0;
    }
}

// File: Arrays.sol



pragma solidity ^0.5.2;

import "./Math.sol";


/**
 * @title Arrays
 * @dev Utility library of inline array functions
 */
library Arrays {
    /**
     * @dev Upper bound search function which is kind of binary search algorithm. It searches sorted
     * array to find index of the element value. If element is found then returns its index otherwise
     * it returns index of first element which is greater than searched value. If searched element is
     * bigger than any array element function then returns first index after last element (i.e. all
     * values inside the array are smaller than the target). Complexity O(log n).
     * @param array The array sorted in ascending order.
     * @param element The element's value to be found.
     * @return The calculated index value. Returns 0 for empty array.
     */
    function findUpperBound(uint256[] storage array, uint256 element) internal view returns (uint256) {
        if (array.length == 0) {
            return 0;
        }

        uint256 low = 0;
        uint256 high = array.length;

        while (low < high) {
            uint256 mid = Math.average(low, high);

            // Note that mid will always be strictly less than high (i.e. it will be a valid array index)
            // because Math.average rounds down (it does integer division with truncation).
            if (array[mid] > element) {
                high = mid;
            } else {
                low = mid + 1;
            }
        }

        // At this point `low` is the exclusive upper bound. We will return the inclusive upper bound.
        if (low > 0 && array[low - 1] == element) {
            return low - 1;
        } else {
            return low;
        }
    }
}

// File: CappedCrowdsale.sol



pragma solidity ^0.5.2;

import "./SafeMath.sol";
import "./Crowdsale.sol";

/**
 * @title CappedCrowdsale
 * @dev Crowdsale with a limit for total contributions.
 */
contract CappedCrowdsale is Crowdsale {
    using SafeMath for uint256;

    uint256 private _cap;

    /**
     * @dev Constructor, takes maximum amount of wei accepted in the crowdsale.
     * @param cap Max amount of wei to be contributed
     */
    constructor (uint256 cap) public {
        require(cap > 0, "cap > 0");
        _cap = cap;
    }

    /**
     * @return the cap of the crowdsale.
     */
    function cap() public view returns (uint256) {
        return _cap;
    }

    /**
     * @dev Checks whether the cap has been reached.
     * @return Whether the cap was reached
     */
    function capReached() public view returns (bool) {
        return weiRaised() >= _cap;
    }

    /**
     * @dev Extend parent behavior requiring purchase to respect the funding cap.
     * @param beneficiary Token purchaser
     * @param weiAmount Amount of wei contributed
     */
    function _preValidatePurchase(address beneficiary, uint256 weiAmount) internal view {
        super._preValidatePurchase(beneficiary, weiAmount);
        require(weiRaised().add(weiAmount) <= _cap);
    }
}

// File: ConditionalEscrow.sol



pragma solidity ^0.5.2;

import "./Escrow.sol";

/**
 * @title ConditionalEscrow
 * @dev Base abstract escrow to only allow withdrawal if a condition is met.
 * @dev Intended usage: See Escrow.sol. Same usage guidelines apply here.
 */
contract ConditionalEscrow is Escrow {
    /**
     * @dev Returns whether an address is allowed to withdraw their funds. To be
     * implemented by derived contracts.
     * @param payee The destination address of the funds.
     */
    function withdrawalAllowed(address payee) public view returns (bool);

    function withdraw(address payable payee) public {
        require(withdrawalAllowed(payee));
        super.withdraw(payee);
    }
}

// File: Crowdsale.sol



pragma solidity ^0.5.2;

import "./IERC20.sol";
import "./SafeMath.sol";
import "./SafeERC20.sol";
import "./ReentrancyGuard.sol";

/**
 * @title Crowdsale
 * @dev Crowdsale is a base contract for managing a token crowdsale,
 * allowing investors to purchase tokens with ether. This contract implements
 * such functionality in its most fundamental form and can be extended to provide additional
 * functionality and/or custom behavior.
 * The external interface represents the basic interface for purchasing tokens, and conforms
 * the base architecture for crowdsales. It is *not* intended to be modified / overridden.
 * The internal interface conforms the extensible and modifiable surface of crowdsales. Override
 * the methods to add functionality. Consider using 'super' where appropriate to concatenate
 * behavior.
 */
contract Crowdsale is ReentrancyGuard {
    using SafeMath for uint256;
    using SafeERC20 for IERC20;

    // The token being sold
    IERC20 internal _token;

    // Address where funds are collected
    address payable internal _wallet;

    // How many token units a buyer gets per wei.
    // The rate is the conversion between wei and the smallest and indivisible token unit.
    // So, if you are using a rate of 1 with a ERC20Detailed token with 3 decimals called TOK
    // 1 wei will give you 1 unit, or 0.001 TOK.
    //uint256 internal _rate;

    // Amount of wei raised
    uint256 internal _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 TokensPurchased(address indexed purchaser, address indexed beneficiary, uint256 value, uint256 amount);

    /**
     * @dev The rate is the conversion between wei and the smallest and indivisible
     * token unit. So, if you are using a rate of 1 with a ERC20Detailed token
     * with 3 decimals called TOK, 1 wei will give you 1 unit, or 0.001 TOK.
     * @param wallet Address where collected funds will be forwarded to
     * @param token Address of the token being sold
     */
    constructor (address payable wallet, IERC20 token) public {
        require(wallet != address(0), "wallet != address(0)");
        require(address(token) != address(0), "address(token) != address(0)");

        _wallet = wallet;
        _token = token;
    }

    /**
     * @dev fallback function ***DO NOT OVERRIDE***
     * Note that other contracts will transfer funds with a base gas stipend
     * of 2300, which is not enough to call buyTokens. Consider calling
     * buyTokens directly when purchasing tokens from a contract.
     */
    function () external payable {
        buyTokens(msg.sender);
    }

    function token() public view returns (IERC20) {
        return _token;
    }

    function wallet() public view returns (address payable) {
        return _wallet;
    }

    function rate() public view returns (uint256) {
        if(now < 1561939200) return uint256(6666);
        else return uint256(5000);
    }

    function weiRaised() public view returns (uint256) {
        return _weiRaised;
    }

    /**
     * @dev low level token purchase ***DO NOT OVERRIDE***
     * This function has a non-reentrancy guard, so it shouldn't be called by
     * another `nonReentrant` function.
     * @param beneficiary Recipient of the token purchase
     */
    function buyTokens(address beneficiary) public nonReentrant payable {
        uint256 weiAmount = msg.value;
        _preValidatePurchase(beneficiary, weiAmount);

        // calculate token amount to be created
        uint256 tokens = _getTokenAmount(weiAmount);

        // update state
        _weiRaised = _weiRaised.add(weiAmount);

        _processPurchase(beneficiary, tokens);
        emit TokensPurchased(msg.sender, beneficiary, weiAmount, tokens);

        _updatePurchasingState(beneficiary, weiAmount);

        _forwardFunds();
        _postValidatePurchase(beneficiary, weiAmount);
    }

    /**
     * @dev Validation of an incoming purchase. Use require statements to revert state when conditions are not met.
     * Use `super` in contracts that inherit from Crowdsale to extend their validations.
     * Example from CappedCrowdsale.sol's _preValidatePurchase method:
     *     super._preValidatePurchase(beneficiary, weiAmount);
     *     require(weiRaised().add(weiAmount) <= cap);
     * @param beneficiary Address performing the token purchase
     * @param weiAmount Value in wei involved in the purchase
     */
    function _preValidatePurchase(address beneficiary, uint256 weiAmount) internal view {
        require(beneficiary != address(0));
        require(weiAmount != 0);
    }

    /**
     * @dev Validation of an executed purchase. Observe state and use revert statements to undo rollback when valid
     * conditions are not met.
     * @param beneficiary Address performing the token purchase
     * @param weiAmount Value in wei involved in the purchase
     */
    function _postValidatePurchase(address beneficiary, uint256 weiAmount) internal view {
        // solhint-disable-previous-line no-empty-blocks
    }

    /**
     * @dev Source of tokens. Override this method to modify the way in which the crowdsale ultimately gets and sends
     * its tokens.
     * @param beneficiary Address performing the token purchase
     * @param tokenAmount Number of tokens to be emitted
     */
    function _deliverTokens(address beneficiary, uint256 tokenAmount) internal {
        _token.safeTransfer(beneficiary, tokenAmount);
    }

    /**
     * @dev Executed when a purchase has been validated and is ready to be executed. Doesn't necessarily emit/send
     * tokens.
     * @param beneficiary Address receiving the tokens
     * @param tokenAmount Number of tokens to be purchased
     */
    function _processPurchase(address beneficiary, uint256 tokenAmount) internal {
        _deliverTokens(beneficiary, tokenAmount);
    }

    /**
     * @dev Override for extensions that require an internal state to check for validity (current user contributions,
     * etc.)
     * @param beneficiary Address receiving the tokens
     * @param weiAmount Value in wei involved in the purchase
     */
    function _updatePurchasingState(address beneficiary, uint256 weiAmount) internal {
        // solhint-disable-previous-line no-empty-blocks
    }

    /**
     * @dev Override to extend the way in which ether is converted to tokens.
     * @param weiAmount Value in wei to be converted into tokens
     * @return Number of tokens that can be purchased with the specified _weiAmount
     */
    function _getTokenAmount(uint256 weiAmount) internal view returns (uint256) {
        uint256 r = rate();
        return weiAmount.mul(r);
    }

    /**
     * @dev Determines how ETH is stored/forwarded on purchases.
     */
    function _forwardFunds() internal {
        _wallet.transfer(msg.value);
    }
}

// File: Escrow.sol



pragma solidity ^0.5.2;

import "./SafeMath.sol";
import "./Secondary.sol";

 /**
  * @title Escrow
  * @dev Base escrow contract, holds funds designated for a payee until they
  * withdraw them.
  * @dev Intended usage: This contract (and derived escrow contracts) should be a
  * standalone contract, that only interacts with the contract that instantiated
  * it. That way, it is guaranteed that all Ether will be handled according to
  * the Escrow rules, and there is no need to check for payable functions or
  * transfers in the inheritance tree. The contract that uses the escrow as its
  * payment method should be its primary, and provide public methods redirecting
  * to the escrow's deposit and withdraw.
  */
contract Escrow is Secondary {
    using SafeMath for uint256;

    event Deposited(address indexed payee, uint256 weiAmount);
    event Withdrawn(address indexed payee, uint256 weiAmount);

    mapping(address => uint256) private _deposits;

    function depositsOf(address payee) public view returns (uint256) {
        return _deposits[payee];
    }

    /**
     * @dev Stores the sent amount as credit to be withdrawn.
     * @param payee The destination address of the funds.
     */
    function deposit(address payee) public onlyPrimary payable {
        uint256 amount = msg.value;
        _deposits[payee] = _deposits[payee].add(amount);

        emit Deposited(payee, amount);
    }

    /**
     * @dev Withdraw accumulated balance for a payee.
     * @param payee The address whose funds will be withdrawn and transferred to.
     */
    function withdraw(address payable payee) public onlyPrimary {
        uint256 payment = _deposits[payee];

        _deposits[payee] = 0;

        payee.transfer(payment);

        emit Withdrawn(payee, payment);
    }
}

// File: EUCXCrowdsale.sol



pragma solidity ^0.5.2;

import "./EUCXToken.sol";
import "./Crowdsale.sol";
import "./Ownable.sol";
import "./RefundableCrowdsale.sol";
import "./CappedCrowdsale.sol";
import "./TimedCrowdsale.sol";
import "./WhitelistCrowdsale.sol";

contract EUCXCrowdsale is Crowdsale, CappedCrowdsale, TimedCrowdsale, WhitelistCrowdsale, RefundableCrowdsale, Ownable
{
    constructor(address payable wallet, IERC20 token, uint256 openingTime, uint256 closingTime)
        Crowdsale(wallet, token)
        CappedCrowdsale(7500 * uint(10**18))
        TimedCrowdsale(openingTime, closingTime)
        WhitelistCrowdsale()
        RefundableCrowdsale(7500 * uint(10**18))
        FinalizableCrowdsale()
        Ownable()
        public
    {
    }

    function claimRefund(address payable refundee) public
    {
        require(finalized(), "Sale not finalized yet");
        require(!goalReached(), "Goal has been reached");
        require(_escrow.depositsOf(refundee) != 0, "Tokens already withdrawn, forfeited on refund");

        _escrow.withdraw(refundee);
    }
}
// File: EUCXToken.sol



pragma solidity ^0.5.2;

import "./SafeMath.sol";
import "./IERC20.sol";
import "./Ownable.sol";
import "./MinterRole.sol";

contract EUCXToken is IERC20, Ownable, MinterRole {
    using SafeMath for uint256;

    mapping (address => uint256) private _balances;
    mapping (address => mapping (address => uint256)) private _allowed;
    uint256 private _totalSupply;
    string private _name;
    string private _symbol;
    uint8 private _decimals;

    constructor() Ownable() public {
        _name = "EUCX Token";
        _symbol = "EUCX";
        _decimals = 18;
        _totalSupply = 1000000000 * uint(10**18);
        _balances[msg.sender] = _totalSupply;
    }

    function name() public view returns (string memory) {
        return _name;
    }

    function symbol() public view returns (string memory) {
        return _symbol;
    }

    function decimals() public view returns (uint8) {
        return _decimals;
    }

    function totalSupply() public view returns (uint256) {
        return _totalSupply;
    }

    function balanceOf(address owner) public view returns (uint256) {
        return _balances[owner];
    }

    function allowance(address owner, address spender) public view returns (uint256) {
        return _allowed[owner][spender];
    }

    function transfer(address to, uint256 value) public returns (bool) {
        _transfer(msg.sender, to, value);
        return true;
    }

    function approve(address spender, uint256 value) public returns (bool) {
        _approve(msg.sender, spender, value);
        return true;
    }

    function transferFrom(address from, address to, uint256 value) public returns (bool) {
        _transfer(from, to, value);
        _approve(from, msg.sender, _allowed[from][msg.sender].sub(value));
        return true;
    }

    function increaseAllowance(address spender, uint256 addedValue) public returns (bool) {
        _approve(msg.sender, spender, _allowed[msg.sender][spender].add(addedValue));
        return true;
    }

    function decreaseAllowance(address spender, uint256 subtractedValue) public returns (bool) {
        _approve(msg.sender, spender, _allowed[msg.sender][spender].sub(subtractedValue));
        return true;
    }

    function mint(address to, uint256 value) public onlyMinter returns (bool) {
        _mint(to, value);
        return true;
    }

    function burn(uint256 value) public onlyMinter {
        _burn(msg.sender, value);
    }

    function burnFrom(address from, uint256 value) public onlyMinter {
        _burnFrom(from, value);
    }

    function _transfer(address from, address to, uint256 value) private {
        require(to != address(0));

        _balances[from] = _balances[from].sub(value);
        _balances[to] = _balances[to].add(value);
        emit Transfer(from, to, value);
    }

    function _mint(address account, uint256 value) private {
        require(account != address(0));
        require(_totalSupply.add(value) <= 1000000000 * uint(10**18));

        _totalSupply = _totalSupply.add(value);
        _balances[account] = _balances[account].add(value);
        emit Transfer(address(0), account, value);
    }

    function _burn(address account, uint256 value) private {
        require(account != address(0));

        _totalSupply = _totalSupply.sub(value);
        _balances[account] = _balances[account].sub(value);
        emit Transfer(account, address(0), value);
    }

    function _burnFrom(address account, uint256 value) private {
        _burn(account, value);
        _approve(account, msg.sender, _allowed[account][msg.sender].sub(value));
    }

    function _approve(address owner, address spender, uint256 value) private {
        require(spender != address(0));
        require(owner != address(0));

        _allowed[owner][spender] = value;
        emit Approval(owner, spender, value);
    }
}
// File: FinalizableCrowdsale.sol



pragma solidity ^0.5.2;

import "./SafeMath.sol";
import "./TimedCrowdsale.sol";

/**
 * @title FinalizableCrowdsale
 * @dev Extension of TimedCrowdsale with a one-off finalization action, where one
 * can do extra work after finishing.
 */
contract FinalizableCrowdsale is TimedCrowdsale {
    using SafeMath for uint256;

    bool private _finalized;

    event CrowdsaleFinalized();

    constructor () internal {
        _finalized = false;
    }

    /**
     * @return true if the crowdsale is finalized, false otherwise.
     */
    function finalized() public view returns (bool) {
        return _finalized;
    }

    /**
     * @dev Must be called after crowdsale ends, to do some extra finalization
     * work. Calls the contract's finalization function.
     */
    function finalize() public {
        require(!_finalized);
        require(hasClosed());

        _finalized = true;

        _finalization();
        emit CrowdsaleFinalized();
    }

    /**
     * @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 {
        // solhint-disable-previous-line no-empty-blocks
    }
}

// File: IERC20.sol



pragma solidity ^0.5.2;

interface IERC20 {
    function transfer(address to, uint256 value) external returns (bool);
    function approve(address spender, uint256 value) external returns (bool);
    function transferFrom(address from, address to, uint256 value) external returns (bool);
    function totalSupply() external view returns (uint256);
    function balanceOf(address who) external view returns (uint256);
    function allowance(address owner, address spender) external view returns (uint256);
    event Transfer(address indexed from, address indexed to, uint256 value);
    event Approval(address indexed owner, address indexed spender, uint256 value);
}
// File: Math.sol



pragma solidity ^0.5.2;

/**
 * @title Math
 * @dev Assorted math operations
 */
library Math {
    /**
     * @dev Returns the largest of two numbers.
     */
    function max(uint256 a, uint256 b) internal pure returns (uint256) {
        return a >= b ? a : b;
    }

    /**
     * @dev Returns the smallest of two numbers.
     */
    function min(uint256 a, uint256 b) internal pure returns (uint256) {
        return a < b ? a : b;
    }

    /**
     * @dev Calculates the average of two numbers. Since these are integers,
     * averages of an even and odd number cannot be represented, and will be
     * rounded down.
     */
    function average(uint256 a, uint256 b) internal pure returns (uint256) {
        // (a + b) / 2 can overflow, so we distribute
        return (a / 2) + (b / 2) + ((a % 2 + b % 2) / 2);
    }
}

// File: Migrations.sol



pragma solidity >=0.4.21 <0.6.0;

contract Migrations {
  address public owner;
  uint public last_completed_migration;

  constructor() public {
    owner = msg.sender;
  }

  modifier restricted() {
    if (msg.sender == owner) _;
  }

  function setCompleted(uint completed) public restricted {
    last_completed_migration = completed;
  }

  function upgrade(address new_address) public restricted {
    Migrations upgraded = Migrations(new_address);
    upgraded.setCompleted(last_completed_migration);
  }
}

// File: MinterRole.sol



pragma solidity ^0.5.2;

import "./Roles.sol";

contract MinterRole {
    using Roles for Roles.Role;

    event MinterAdded(address indexed account);
    event MinterRemoved(address indexed account);

    Roles.Role private _minters;

    constructor () internal {
        _addMinter(msg.sender);
    }

    modifier onlyMinter() {
        require(isMinter(msg.sender));
        _;
    }

    function isMinter(address account) public view returns (bool) {
        return _minters.has(account);
    }

    function addMinter(address account) public onlyMinter {
        _addMinter(account);
    }

    function renounceMinter() public {
        _removeMinter(msg.sender);
    }

    function _addMinter(address account) internal {
        _minters.add(account);
        emit MinterAdded(account);
    }

    function _removeMinter(address account) internal {
        _minters.remove(account);
        emit MinterRemoved(account);
    }
}
// File: Ownable.sol



pragma solidity ^0.5.2;

/**
 * @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 private _owner;

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

    /**
     * @dev The Ownable constructor sets the original `owner` of the contract to the sender
     * account.
     */
    constructor () internal {
        _owner = msg.sender;
        emit OwnershipTransferred(address(0), _owner);
    }

    /**
     * @return the address of the owner.
     */
    function owner() public view returns (address) {
        return _owner;
    }

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

    /**
     * @return true if `msg.sender` is the owner of the contract.
     */
    function isOwner() public view returns (bool) {
        return msg.sender == _owner;
    }

    /**
     * @dev Allows the current owner to relinquish control of the contract.
     * It will not be possible to call the functions with the `onlyOwner`
     * modifier anymore.
     * @notice Renouncing ownership will leave the contract without an owner,
     * thereby removing any functionality that is only available to the owner.
     */
    function renounceOwnership() public onlyOwner {
        emit OwnershipTransferred(_owner, address(0));
        _owner = address(0);
    }

    /**
     * @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 {
        _transferOwnership(newOwner);
    }

    /**
     * @dev Transfers control of the contract to a newOwner.
     * @param newOwner The address to transfer ownership to.
     */
    function _transferOwnership(address newOwner) internal {
        require(newOwner != address(0));
        emit OwnershipTransferred(_owner, newOwner);
        _owner = newOwner;
    }
}

// File: ReentrancyGuard.sol



pragma solidity ^0.5.2;

/**
 * @title Helps contracts guard against reentrancy attacks.
 * @author Remco Bloemen <remco@2π.com>, Eenae <alexey@mixbytes.io>
 * @dev If you mark a function `nonReentrant`, you should also
 * mark it `external`.
 */
contract ReentrancyGuard {
    /// @dev counter to allow mutex lock with only one SSTORE operation
    uint256 private _guardCounter;

    constructor () internal {
        // The counter starts at one to prevent changing it from zero to a non-zero
        // value, which is a more expensive operation.
        _guardCounter = 1;
    }

    /**
     * @dev Prevents a contract from calling itself, directly or indirectly.
     * Calling a `nonReentrant` function from another `nonReentrant`
     * function is not supported. It is possible to prevent this from happening
     * by making the `nonReentrant` function external, and make it call a
     * `private` function that does the actual work.
     */
    modifier nonReentrant() {
        _guardCounter += 1;
        uint256 localCounter = _guardCounter;
        _;
        require(localCounter == _guardCounter);
    }
}

// File: RefundableCrowdsale.sol



pragma solidity ^0.5.2;

import "./SafeMath.sol";
import "./FinalizableCrowdsale.sol";
import "./RefundEscrow.sol";

/**
 * @title RefundableCrowdsale
 * @dev Extension of FinalizableCrowdsale contract that adds a funding goal, and the possibility of users
 * getting a refund if goal is not met.
 *
 * Deprecated, use RefundablePostDeliveryCrowdsale instead. Note that if you allow tokens to be traded before the goal
 * is met, then an attack is possible in which the attacker purchases tokens from the crowdsale and when they sees that
 * the goal is unlikely to be met, they sell their tokens (possibly at a discount). The attacker will be refunded when
 * the crowdsale is finalized, and the users that purchased from them will be left with worthless tokens.
 */
contract RefundableCrowdsale is FinalizableCrowdsale {
    using SafeMath for uint256;

    // minimum amount of funds to be raised in weis
    uint256 internal _goal;

    // refund escrow used to hold funds while crowdsale is running
    RefundEscrow internal _escrow;

    /**
     * @dev Constructor, creates RefundEscrow.
     * @param goal Funding goal
     */
    constructor (uint256 goal) public {
        require(goal > 0, "goal > 0");
        _escrow = new RefundEscrow(wallet());
        _goal = goal;
    }

    /**
     * @return minimum amount of funds to be raised in wei.
     */
    function goal() public view returns (uint256) {
        return _goal;
    }

    /**
     * @dev Investors can claim refunds here if crowdsale is unsuccessful
     * @param refundee Whose refund will be claimed.
     */
    function claimRefund(address payable refundee) public {
        require(finalized());
        require(!goalReached());

        _escrow.withdraw(refundee);
    }

    /**
     * @dev Checks whether funding goal was reached.
     * @return Whether funding goal was reached
     */
    function goalReached() public view returns (bool) {
        return weiRaised() >= _goal;
    }

    /**
     * @dev escrow finalization task, called when finalize() is called
     */
    function _finalization() internal {
        if (goalReached()) {
            _escrow.close();
            _escrow.beneficiaryWithdraw();
        } else {
            _escrow.enableRefunds();
        }

        super._finalization();
    }

    /**
     * @dev Overrides Crowdsale fund forwarding, sending funds to escrow.
     */
    function _forwardFunds() internal {
        _escrow.deposit.value(msg.value)(msg.sender);
    }
}

// File: RefundEscrow.sol



pragma solidity ^0.5.2;

import "./ConditionalEscrow.sol";

/**
 * @title RefundEscrow
 * @dev Escrow that holds funds for a beneficiary, deposited from multiple
 * parties.
 * @dev Intended usage: See Escrow.sol. Same usage guidelines apply here.
 * @dev The primary account (that is, the contract that instantiates this
 * contract) may deposit, close the deposit period, and allow for either
 * withdrawal by the beneficiary, or refunds to the depositors. All interactions
 * with RefundEscrow will be made through the primary contract. See the
 * RefundableCrowdsale contract for an example of RefundEscrow’s use.
 */
contract RefundEscrow is ConditionalEscrow {
    enum State { Active, Refunding, Closed }

    event RefundsClosed();
    event RefundsEnabled();

    State private _state;
    address payable private _beneficiary;

    /**
     * @dev Constructor.
     * @param beneficiary The beneficiary of the deposits.
     */
    constructor (address payable beneficiary) public {
        require(beneficiary != address(0));
        _beneficiary = beneficiary;
        _state = State.Active;
    }

    /**
     * @return the current state of the escrow.
     */
    function state() public view returns (State) {
        return _state;
    }

    /**
     * @return the beneficiary of the escrow.
     */
    function beneficiary() public view returns (address) {
        return _beneficiary;
    }

    /**
     * @dev Stores funds that may later be refunded.
     * @param refundee The address funds will be sent to if a refund occurs.
     */
    function deposit(address refundee) public payable {
        require(_state == State.Active);
        super.deposit(refundee);
    }

    /**
     * @dev Allows for the beneficiary to withdraw their funds, rejecting
     * further deposits.
     */
    function close() public onlyPrimary {
        require(_state == State.Active);
        _state = State.Closed;
        emit RefundsClosed();
    }

    /**
     * @dev Allows for refunds to take place, rejecting further deposits.
     */
    function enableRefunds() public onlyPrimary {
        require(_state == State.Active);
        _state = State.Refunding;
        emit RefundsEnabled();
    }

    /**
     * @dev Withdraws the beneficiary's funds.
     */
    function beneficiaryWithdraw() public {
        require(_state == State.Closed);
        _beneficiary.transfer(address(this).balance);
    }

    /**
     * @dev Returns whether refundees can withdraw their deposits (be refunded). The overridden function receives a
     * 'payee' argument, but we ignore it here since the condition is global, not per-payee.
     */
    function withdrawalAllowed(address) public view returns (bool) {
        return _state == State.Refunding;
    }
}

// File: Roles.sol



pragma solidity ^0.5.2;

library Roles {
    struct Role {
        mapping (address => bool) bearer;
    }

    function add(Role storage role, address account) internal {
        require(account != address(0));
        require(!has(role, account));
        role.bearer[account] = true;
    }

    function remove(Role storage role, address account) internal {
        require(account != address(0));
        require(has(role, account));
        role.bearer[account] = false;
    }

    function has(Role storage role, address account) internal view returns (bool) {
        require(account != address(0));
        return role.bearer[account];
    }
}
// File: SafeERC20.sol



pragma solidity ^0.5.2;

import "./IERC20.sol";
import "./SafeMath.sol";
import "./Address.sol";

/**
 * @title SafeERC20
 * @dev Wrappers around ERC20 operations that throw on failure (when the token
 * contract returns false). Tokens that return no value (and instead revert or
 * throw on failure) are also supported, non-reverting calls are assumed to be
 * successful.
 * To use this library you can add a `using SafeERC20 for ERC20;` statement to your contract,
 * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
 */
library SafeERC20 {
    using SafeMath for uint256;
    using Address for address;

    function safeTransfer(IERC20 token, address to, uint256 value) internal {
        callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
    }

    function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
        callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
    }

    function safeApprove(IERC20 token, address spender, uint256 value) internal {
        // safeApprove should only be called when setting an initial allowance,
        // or when resetting it to zero. To increase and decrease it, use
        // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
        require((value == 0) || (token.allowance(address(this), spender) == 0));
        callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
    }

    function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        uint256 newAllowance = token.allowance(address(this), spender).add(value);
        callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }

    function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        uint256 newAllowance = token.allowance(address(this), spender).sub(value);
        callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }

    /**
     * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
     * on the return value: the return value is optional (but if data is returned, it must equal true).
     * @param token The token targeted by the call.
     * @param data The call data (encoded using abi.encode or one of its variants).
     */
    function callOptionalReturn(IERC20 token, bytes memory data) private {
        // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
        // we're implementing it ourselves.

        // A Solidity high level call has three parts:
        //  1. The target address is checked to verify it contains contract code
        //  2. The call itself is made, and success asserted
        //  3. The return value is decoded, which in turn checks the size of the returned data.

        require(address(token).isContract());

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = address(token).call(data);
        require(success);

        if (returndata.length > 0) { // Return data is optional
            require(abi.decode(returndata, (bool)));
        }
    }
}

// File: SafeMath.sol



pragma solidity ^0.5.2;

library SafeMath {
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        if (a == 0) {
            return 0;
        }
        uint256 c = a * b;
        require(c / a == b);
        return c;
    }

    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b > 0);
        uint256 c = a / b;
        return c;
    }

    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b <= a);
        uint256 c = a - b;
        return c;
    }

    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a);
        return c;
    }

    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b != 0);
        return a % b;
    }
}
// File: Secondary.sol



pragma solidity ^0.5.2;

/**
 * @title Secondary
 * @dev A Secondary contract can only be used by its primary account (the one that created it)
 */
contract Secondary {
    address private _primary;

    event PrimaryTransferred(
        address recipient
    );

    /**
     * @dev Sets the primary account to the one that is creating the Secondary contract.
     */
    constructor () internal {
        _primary = msg.sender;
        emit PrimaryTransferred(_primary);
    }

    /**
     * @dev Reverts if called from any account other than the primary.
     */
    modifier onlyPrimary() {
        require(msg.sender == _primary);
        _;
    }

    /**
     * @return the address of the primary.
     */
    function primary() public view returns (address) {
        return _primary;
    }

    /**
     * @dev Transfers contract to a new primary.
     * @param recipient The address of new primary.
     */
    function transferPrimary(address recipient) public onlyPrimary {
        require(recipient != address(0));
        _primary = recipient;
        emit PrimaryTransferred(_primary);
    }
}

// File: TimedCrowdsale.sol



pragma solidity ^0.5.2;

import "./SafeMath.sol";
import "./Crowdsale.sol";

/**
 * @title TimedCrowdsale
 * @dev Crowdsale accepting contributions only within a time frame.
 */
contract TimedCrowdsale is Crowdsale {
    using SafeMath for uint256;

    uint256 private _openingTime;
    uint256 private _closingTime;

    /**
     * Event for crowdsale extending
     * @param newClosingTime new closing time
     * @param prevClosingTime old closing time
     */
    event TimedCrowdsaleExtended(uint256 prevClosingTime, uint256 newClosingTime);

    /**
     * @dev Reverts if not in crowdsale time range.
     */
    modifier onlyWhileOpen {
        require(isOpen());
        _;
    }

    /**
     * @dev Constructor, takes crowdsale opening and closing times.
     * @param openingTime Crowdsale opening time
     * @param closingTime Crowdsale closing time
     */
    constructor (uint256 openingTime, uint256 closingTime) public {
        // solhint-disable-next-line not-rely-on-time
        require(closingTime > openingTime, "closingTime > openingTime");

        _openingTime = openingTime;
        _closingTime = closingTime;
    }

    /**
     * @return the crowdsale opening time.
     */
    function openingTime() public view returns (uint256) {
        return _openingTime;
    }

    /**
     * @return the crowdsale closing time.
     */
    function closingTime() public view returns (uint256) {
        return _closingTime;
    }

    /**
     * @return true if the crowdsale is open, false otherwise.
     */
    function isOpen() public view returns (bool) {
        // solhint-disable-next-line not-rely-on-time
        return block.timestamp >= _openingTime && block.timestamp <= _closingTime;
    }

    /**
     * @dev Checks whether the period in which the crowdsale is open has already elapsed.
     * @return Whether crowdsale period has elapsed
     */
    function hasClosed() public view returns (bool) {
        // solhint-disable-next-line not-rely-on-time
        return block.timestamp > _closingTime;
    }

    /**
     * @dev Extend parent behavior requiring to be within contributing period
     * @param beneficiary Token purchaser
     * @param weiAmount Amount of wei contributed
     */
    function _preValidatePurchase(address beneficiary, uint256 weiAmount) internal onlyWhileOpen view {
        super._preValidatePurchase(beneficiary, weiAmount);
    }

    /**
     * @dev Extend crowdsale
     * @param newClosingTime Crowdsale closing time
     */
    function _extendTime(uint256 newClosingTime) internal {
        require(!hasClosed());
        require(newClosingTime > _closingTime);

        emit TimedCrowdsaleExtended(_closingTime, newClosingTime);
        _closingTime = newClosingTime;
    }
}

// File: WhitelistAdminRole.sol



pragma solidity ^0.5.2;

import "./Roles.sol";

/**
 * @title WhitelistAdminRole
 * @dev WhitelistAdmins are responsible for assigning and removing Whitelisted accounts.
 */
contract WhitelistAdminRole {
    using Roles for Roles.Role;

    event WhitelistAdminAdded(address indexed account);
    event WhitelistAdminRemoved(address indexed account);

    Roles.Role private _whitelistAdmins;

    constructor () internal {
        _addWhitelistAdmin(msg.sender);
    }

    modifier onlyWhitelistAdmin() {
        require(isWhitelistAdmin(msg.sender));
        _;
    }

    function isWhitelistAdmin(address account) public view returns (bool) {
        return _whitelistAdmins.has(account);
    }

    function addWhitelistAdmin(address account) public onlyWhitelistAdmin {
        _addWhitelistAdmin(account);
    }

    function renounceWhitelistAdmin() public {
        _removeWhitelistAdmin(msg.sender);
    }

    function _addWhitelistAdmin(address account) internal {
        _whitelistAdmins.add(account);
        emit WhitelistAdminAdded(account);
    }

    function _removeWhitelistAdmin(address account) internal {
        _whitelistAdmins.remove(account);
        emit WhitelistAdminRemoved(account);
    }
}

// File: WhitelistCrowdsale.sol



pragma solidity ^0.5.2;

import "./Crowdsale.sol";
import "./WhitelistedRole.sol";


/**
 * @title WhitelistCrowdsale
 * @dev Crowdsale in which only whitelisted users can contribute.
 */
contract WhitelistCrowdsale is WhitelistedRole, Crowdsale {
    /**
     * @dev Extend parent behavior requiring beneficiary to be whitelisted. Note that no
     * restriction is imposed on the account sending the transaction.
     * @param _beneficiary Token beneficiary
     * @param _weiAmount Amount of wei contributed
     */
    function _preValidatePurchase(address _beneficiary, uint256 _weiAmount) internal view {
        require(isWhitelisted(_beneficiary));
        super._preValidatePurchase(_beneficiary, _weiAmount);
    }
}

// File: WhitelistedRole.sol



pragma solidity ^0.5.2;

import "./Roles.sol";
import "./WhitelistAdminRole.sol";

/**
 * @title WhitelistedRole
 * @dev Whitelisted accounts have been approved by a WhitelistAdmin to perform certain actions (e.g. participate in a
 * crowdsale). This role is special in that the only accounts that can add it are WhitelistAdmins (who can also remove
 * it), and not Whitelisteds themselves.
 */
contract WhitelistedRole is WhitelistAdminRole {
    using Roles for Roles.Role;

    event WhitelistedAdded(address indexed account);
    event WhitelistedRemoved(address indexed account);

    Roles.Role private _whitelisteds;

    modifier onlyWhitelisted() {
        require(isWhitelisted(msg.sender));
        _;
    }

    function isWhitelisted(address account) public view returns (bool) {
        return _whitelisteds.has(account);
    }

    function addWhitelisted(address account) public onlyWhitelistAdmin {
        _addWhitelisted(account);
    }

    function removeWhitelisted(address account) public onlyWhitelistAdmin {
        _removeWhitelisted(account);
    }

    function renounceWhitelisted() public {
        _removeWhitelisted(msg.sender);
    }

    function _addWhitelisted(address account) internal {
        _whitelisteds.add(account);
        emit WhitelistedAdded(account);
    }

    function _removeWhitelisted(address account) internal {
        _whitelisteds.remove(account);
        emit WhitelistedRemoved(account);
    }
}