pragma solidity ^0.5.17;

/*
$$\                 $$\       $$\  $$$$$$\            
$$ |                $$ |      $$ |$$ ___$$\           
$$$$$$$\   $$$$$$\  $$ | $$$$$$$ |\_/   $$ | $$$$$$\  
$$  __$$\ $$  __$$\ $$ |$$  __$$ |  $$$$$ / $$  __$$\ 
$$ |  $$ |$$ /  $$ |$$ |$$ /  $$ |  \___$$\ $$ |  \__|
$$ |  $$ |$$ |  $$ |$$ |$$ |  $$ |$$\   $$ |$$ |      
$$ |  $$ |\$$$$$$  |$$ |\$$$$$$$ |\$$$$$$  |$$ |      
\__|  \__| \______/ \__| \_______| \______/ \__|
*/

// File: @openzeppelin/contracts/GSN/Context.sol

/*
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with GSN meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
contract Context {
    // Empty internal constructor, to prevent people from mistakenly deploying
    // an instance of this contract, which should be used via inheritance.
    constructor() internal {}

    // solhint-disable-previous-line no-empty-blocks

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

    function _msgData() internal view returns (bytes memory) {
        this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
        return msg.data;
    }
}

// File: @openzeppelin/contracts/token/ERC20/IERC20.sol

/**
 * @dev Interface of the ERC20 standard as defined in the EIP. Does not include
 * the optional functions; to access them see {ERC20Detailed}.
 */
interface IERC20 {
    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);

    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);

    /**
     * @dev Moves `amount` tokens from the caller's account to `recipient`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address recipient, uint256 amount)
        external
        returns (bool);

    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender)
        external
        view
        returns (uint256);

    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: 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
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);

    /**
     * @dev Moves `amount` tokens from `sender` to `recipient` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(
        address sender,
        address recipient,
        uint256 amount
    ) external returns (bool);

    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);

    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(
        address indexed owner,
        address indexed spender,
        uint256 value
    );
}

// File: @openzeppelin/contracts/math/SafeMath.sol

/**
 * @dev Wrappers over Solidity's arithmetic operations with added overflow
 * checks.
 *
 * Arithmetic operations in Solidity wrap on overflow. This can easily result
 * in bugs, because programmers usually assume that an overflow raises an
 * error, which is the standard behavior in high level programming languages.
 * `SafeMath` restores this intuition by reverting the transaction when an
 * operation overflows.
 *
 * Using this library instead of the unchecked operations eliminates an entire
 * class of bugs, so it's recommended to use it always.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `+` operator.
     *
     * Requirements:
     * - Addition cannot overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a, "SafeMath: addition overflow");

        return c;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        return sub(a, b, "SafeMath: subtraction overflow");
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     * - Subtraction cannot overflow.
     *
     * _Available since v2.4.0._
     */
    function sub(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        require(b <= a, errorMessage);
        uint256 c = a - b;

        return c;
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     * - Multiplication cannot overflow.
     */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
        // benefit is lost if 'b' is also tested.
        // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
        if (a == 0) {
            return 0;
        }

        uint256 c = a * b;
        require(c / a == b, "SafeMath: multiplication overflow");

        return c;
    }

    /**
     * @dev Returns the integer division of two unsigned integers. Reverts on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        return div(a, b, "SafeMath: division by zero");
    }

    /**
     * @dev Returns the integer division of two unsigned integers. Reverts with custom message on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     * - The divisor cannot be zero.
     *
     * _Available since v2.4.0._
     */
    function div(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        // Solidity only automatically asserts when dividing by 0
        require(b > 0, errorMessage);
        uint256 c = a / b;
        // assert(a == b * c + a % b); // There is no case in which this doesn't hold

        return c;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * Reverts when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        return mod(a, b, "SafeMath: modulo by zero");
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * Reverts with custom message when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     * - The divisor cannot be zero.
     *
     * _Available since v2.4.0._
     */
    function mod(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        require(b != 0, errorMessage);
        return a % b;
    }
}

// File: @openzeppelin/contracts/utils/Address.sol

/**
 * @dev Collection of functions related to the address type
 */
library Address {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // According to EIP-1052, 0x0 is the value returned for not-yet created accounts
        // and 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470 is returned
        // for accounts without code, i.e. `keccak256('')`
        bytes32 codehash;


            bytes32 accountHash
         = 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470;
        // solhint-disable-next-line no-inline-assembly
        assembly {
            codehash := extcodehash(account)
        }
        return (codehash != accountHash && codehash != 0x0);
    }

    /**
     * @dev Converts an `address` into `address payable`. Note that this is
     * simply a type cast: the actual underlying value is not changed.
     *
     * _Available since v2.4.0._
     */
    function toPayable(address account)
        internal
        pure
        returns (address payable)
    {
        return address(uint160(account));
    }

    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     *
     * _Available since v2.4.0._
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(
            address(this).balance >= amount,
            "Address: insufficient balance"
        );

        // solhint-disable-next-line avoid-call-value
        (bool success, ) = recipient.call.value(amount)("");
        require(
            success,
            "Address: unable to send value, recipient may have reverted"
        );
    }
}

// File: @openzeppelin/contracts/token/ERC20/SafeERC20.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'
        // solhint-disable-next-line max-line-length
        require(
            (value == 0) || (token.allowance(address(this), spender) == 0),
            "SafeERC20: approve from non-zero to non-zero allowance"
        );
        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,
            "SafeERC20: decreased allowance below zero"
        );
        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 not be false).
     * @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.
        // solhint-disable-next-line max-line-length
        require(address(token).isContract(), "SafeERC20: call to non-contract");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = address(token).call(data);
        require(success, "SafeERC20: low-level call failed");

        if (returndata.length > 0) {
            // Return data is optional
            // solhint-disable-next-line max-line-length
            require(
                abi.decode(returndata, (bool)),
                "SafeERC20: ERC20 operation did not succeed"
            );
        }
    }
}

// File: @openzeppelin/contracts/utils/ReentrancyGuard.sol

/**
 * @dev Contract module that helps prevent reentrant calls to a function.
 *
 * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
 * available, which can be applied to functions to make sure there are no nested
 * (reentrant) calls to them.
 *
 * Note that because there is a single `nonReentrant` guard, functions marked as
 * `nonReentrant` may not call one another. This can be worked around by making
 * those functions `private`, and then adding `external` `nonReentrant` entry
 * points to them.
 *
 * TIP: If you would like to learn more about reentrancy and alternative ways
 * to protect against it, check out our blog post
 * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
 *
 * _Since v2.5.0:_ this module is now much more gas efficient, given net gas
 * metering changes introduced in the Istanbul hardfork.
 */
contract ReentrancyGuard {
    bool private _notEntered;

    constructor() internal {
        // Storing an initial non-zero value makes deployment a bit more
        // expensive, but in exchange the refund on every call to nonReentrant
        // will be lower in amount. Since refunds are capped to a percetange of
        // the total transaction's gas, it is best to keep them low in cases
        // like this one, to increase the likelihood of the full refund coming
        // into effect.
        _notEntered = true;
    }

    /**
     * @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() {
        // On the first call to nonReentrant, _notEntered will be true
        require(_notEntered, "ReentrancyGuard: reentrant call");

        // Any calls to nonReentrant after this point will fail
        _notEntered = false;

        _;

        // By storing the original value once again, a refund is triggered (see
        // https://eips.ethereum.org/EIPS/eip-2200)
        _notEntered = true;
    }
}

// File: @openzeppelin/contracts/crowdsale/Crowdsale.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 Context, ReentrancyGuard {
    using SafeMath for uint256;
    using SafeERC20 for IERC20;

    // The token being sold
    IERC20 private _token;

    // Address where funds are collected
    address payable private _wallet;
    address payable private _defaultRef;

    // 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 private _rate;

    // Amount of wei raised
    uint256 private _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
    );

    /**
     * @param rate Number of token units a buyer gets per wei
     * @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(
        uint256 rate,
        address payable wallet,
        IERC20 token
    ) public {
        require(rate > 0, "Crowdsale: rate is 0");
        require(wallet != address(0), "Crowdsale: wallet is the zero address");
        require(
            address(token) != address(0),
            "Crowdsale: token is the zero address"
        );

        _rate = rate;
        _wallet = wallet;
        _defaultRef = _msgSender();
        _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(_msgSender(), _defaultRef);
    }

    /**
     * @return the token being sold.
     */
    function token() public view returns (IERC20) {
        return _token;
    }

    /**
     * @return the address where funds are collected.
     */
    function wallet() public view returns (address payable) {
        return _wallet;
    }

    /**
     * @return the number of token units a buyer gets per wei.
     */
    function rate() public view returns (uint256) {
        return _rate;
    }

    /**
     * @return the amount of wei raised.
     */
    function weiRaised() public view returns (uint256) {
        return _weiRaised;
    }

    function getRefReceiver(address payable _ref)
        private
        view
        returns (address payable)
    {
        return
            (_ref == address(0) ||
                _ref == address(1) ||
                _ref == _msgSender())
                ? _defaultRef
                : _ref;
    }

    /**
     * @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, address payable _ref)
        public
        payable
        nonReentrant
    {
        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(_msgSender(), beneficiary, weiAmount, tokens);

        _updatePurchasingState(beneficiary, weiAmount);

        _forwardFunds(_ref);
        _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),
            "Crowdsale: beneficiary is the zero address"
        );
        require(weiAmount != 0, "Crowdsale: weiAmount is 0");
        this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
    }

    /**
     * @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)
    {
        return weiAmount.mul(_rate);
    }

    uint256 public RATE_REF = 5;

    /**
     * @dev Determines how ETH is stored/forwarded on purchases.
     */
    function _forwardFunds(address payable _ref) internal {
        uint256 weiAmount = msg.value;
        uint256 refAmount = weiAmount.mul(5).div(100);
        getRefReceiver(_ref).transfer(refAmount);
        _wallet.transfer(weiAmount.sub(refAmount));
    }
}

// File: @openzeppelin/contracts/crowdsale/validation/TimedCrowdsale.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(), "TimedCrowdsale: not open");
        _;
    }

    /**
     * @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(
        //     openingTime >= block.timestamp,
        //     "TimedCrowdsale: opening time is before current time"
        // );
        // solhint-disable-next-line max-line-length
        require(
            closingTime > openingTime,
            "TimedCrowdsale: opening time is not before closing time"
        );

        _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;
    }
    
    function withdrawable() public view returns (bool) {
        // solhint-disable-next-line not-rely-on-time
        return block.timestamp > _closingTime.add(30 minutes);
    }

    /**
     * @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
        view
        onlyWhileOpen
    {
        super._preValidatePurchase(beneficiary, weiAmount);
    }

    /**
     * @dev Extend crowdsale.
     * @param newClosingTime Crowdsale closing time
     */
    function _extendTime(uint256 newClosingTime) internal {
        require(!hasClosed(), "TimedCrowdsale: already closed");
        // solhint-disable-next-line max-line-length
        require(
            newClosingTime > _closingTime,
            "TimedCrowdsale: new closing time is before current closing time"
        );

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

// File: @openzeppelin/contracts/ownership/Secondary.sol

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

    /**
     * @dev Emitted when the primary contract changes.
     */
    event PrimaryTransferred(address recipient);

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

    /**
     * @dev Reverts if called from any account other than the primary.
     */
    modifier onlyPrimary() {
        require(
            _msgSender() == _primary,
            "Secondary: caller is not the primary account"
        );
        _;
    }

    /**
     * @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),
            "Secondary: new primary is the zero address"
        );
        _primary = recipient;
        emit PrimaryTransferred(recipient);
    }
}

// File: @openzeppelin/contracts/crowdsale/distribution/PostDeliveryCrowdsale.sol

/**
 * @title PostDeliveryCrowdsale
 * @dev Crowdsale that locks tokens from withdrawal until it ends.
 */
contract PostDeliveryCrowdsale is TimedCrowdsale {
    using SafeMath for uint256;

    mapping(address => uint256) private _balances;
    __unstable__TokenVault private _vault;

    constructor() public {
        _vault = new __unstable__TokenVault();
    }

    /**
     * @dev Withdraw tokens only after crowdsale ends.
     * @param beneficiary Whose tokens will be withdrawn.
     */
    function withdrawTokens(address beneficiary) public {
        require(withdrawable());
        uint256 amount = _balances[beneficiary];
        require(
            amount > 0,
            "PostDeliveryCrowdsale: beneficiary is not due any tokens"
        );

        _balances[beneficiary] = 0;
        _vault.transfer(token(), beneficiary, amount);
    }

    /**
     * @return the balance of an account.
     */
    function balanceOf(address account) public view returns (uint256) {
        return _balances[account];
    }

    /**
     * @dev Overrides parent by storing due balances, and delivering tokens to the vault instead of the end user. This
     * ensures that the tokens will be available by the time they are withdrawn (which may not be the case if
     * `_deliverTokens` was called later).
     * @param beneficiary Token purchaser
     * @param tokenAmount Amount of tokens purchased
     */
    function _processPurchase(address beneficiary, uint256 tokenAmount)
        internal
    {
        _balances[beneficiary] = _balances[beneficiary].add(tokenAmount);
        _deliverTokens(address(_vault), tokenAmount);
    }
}

/**
 * @title __unstable__TokenVault
 * @dev Similar to an Escrow for tokens, this contract allows its primary account to spend its tokens as it sees fit.
 * This contract is an internal helper for PostDeliveryCrowdsale, and should not be used outside of this context.
 */
// solhint-disable-next-line contract-name-camelcase
contract __unstable__TokenVault is Secondary {
    function transfer(
        IERC20 token,
        address to,
        uint256 amount
    ) public onlyPrimary {
        token.transfer(to, amount);
    }
}

// File: @openzeppelin/contracts/token/ERC20/ERC20.sol

/**
 * @dev Implementation of the {IERC20} interface.
 *
 * This implementation is agnostic to the way tokens are created. This means
 * that a supply mechanism has to be added in a derived contract using {_mint}.
 * For a generic mechanism see {ERC20Mintable}.
 *
 * TIP: For a detailed writeup see our guide
 * https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How
 * to implement supply mechanisms].
 *
 * We have followed general OpenZeppelin guidelines: functions revert instead
 * of returning `false` on failure. This behavior is nonetheless conventional
 * and does not conflict with the expectations of ERC20 applications.
 *
 * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
 * This allows applications to reconstruct the allowance for all accounts just
 * by listening to said events. Other implementations of the EIP may not emit
 * these events, as it isn't required by the specification.
 *
 * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
 * functions have been added to mitigate the well-known issues around setting
 * allowances. See {IERC20-approve}.
 */
contract ERC20 is Context, IERC20 {
    using SafeMath for uint256;

    mapping(address => uint256) private _balances;

    mapping(address => mapping(address => uint256)) private _allowances;

    uint256 private _totalSupply;

    /**
     * @dev See {IERC20-totalSupply}.
     */
    function totalSupply() public view returns (uint256) {
        return _totalSupply;
    }

    /**
     * @dev See {IERC20-balanceOf}.
     */
    function balanceOf(address account) public view returns (uint256) {
        return _balances[account];
    }

    /**
     * @dev See {IERC20-transfer}.
     *
     * Requirements:
     *
     * - `recipient` cannot be the zero address.
     * - the caller must have a balance of at least `amount`.
     */
    function transfer(address recipient, uint256 amount) public returns (bool) {
        _transfer(_msgSender(), recipient, amount);
        return true;
    }

    /**
     * @dev See {IERC20-allowance}.
     */
    function allowance(address owner, address spender)
        public
        view
        returns (uint256)
    {
        return _allowances[owner][spender];
    }

    /**
     * @dev See {IERC20-approve}.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function approve(address spender, uint256 amount) public returns (bool) {
        _approve(_msgSender(), spender, amount);
        return true;
    }

    /**
     * @dev See {IERC20-transferFrom}.
     *
     * Emits an {Approval} event indicating the updated allowance. This is not
     * required by the EIP. See the note at the beginning of {ERC20};
     *
     * Requirements:
     * - `sender` and `recipient` cannot be the zero address.
     * - `sender` must have a balance of at least `amount`.
     * - the caller must have allowance for `sender`'s tokens of at least
     * `amount`.
     */
    function transferFrom(
        address sender,
        address recipient,
        uint256 amount
    ) public returns (bool) {
        _transfer(sender, recipient, amount);
        _approve(
            sender,
            _msgSender(),
            _allowances[sender][_msgSender()].sub(
                amount,
                "ERC20: transfer amount exceeds allowance"
            )
        );
        return true;
    }

    /**
     * @dev Atomically increases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function increaseAllowance(address spender, uint256 addedValue)
        public
        returns (bool)
    {
        _approve(
            _msgSender(),
            spender,
            _allowances[_msgSender()][spender].add(addedValue)
        );
        return true;
    }

    /**
     * @dev Atomically decreases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `spender` must have allowance for the caller of at least
     * `subtractedValue`.
     */
    function decreaseAllowance(address spender, uint256 subtractedValue)
        public
        returns (bool)
    {
        _approve(
            _msgSender(),
            spender,
            _allowances[_msgSender()][spender].sub(
                subtractedValue,
                "ERC20: decreased allowance below zero"
            )
        );
        return true;
    }

    /**
     * @dev Moves tokens `amount` from `sender` to `recipient`.
     *
     * This is internal function is equivalent to {transfer}, and can be used to
     * e.g. implement automatic token fees, slashing mechanisms, etc.
     *
     * Emits a {Transfer} event.
     *
     * Requirements:
     *
     * - `sender` cannot be the zero address.
     * - `recipient` cannot be the zero address.
     * - `sender` must have a balance of at least `amount`.
     */
    function _transfer(
        address sender,
        address recipient,
        uint256 amount
    ) internal {
        require(sender != address(0), "ERC20: transfer from the zero address");
        require(recipient != address(0), "ERC20: transfer to the zero address");

        _balances[sender] = _balances[sender].sub(
            amount,
            "ERC20: transfer amount exceeds balance"
        );
        _balances[recipient] = _balances[recipient].add(amount);
        emit Transfer(sender, recipient, amount);
    }

    /** @dev Creates `amount` tokens and assigns them to `account`, increasing
     * the total supply.
     *
     * Emits a {Transfer} event with `from` set to the zero address.
     *
     * Requirements
     *
     * - `to` cannot be the zero address.
     */
    function _mint(address account, uint256 amount) internal {
        require(account != address(0), "ERC20: mint to the zero address");

        _totalSupply = _totalSupply.add(amount);
        _balances[account] = _balances[account].add(amount);
        emit Transfer(address(0), account, amount);
    }

    /**
     * @dev Destroys `amount` tokens from `account`, reducing the
     * total supply.
     *
     * Emits a {Transfer} event with `to` set to the zero address.
     *
     * Requirements
     *
     * - `account` cannot be the zero address.
     * - `account` must have at least `amount` tokens.
     */
    function _burn(address account, uint256 amount) internal {
        require(account != address(0), "ERC20: burn from the zero address");

        _balances[account] = _balances[account].sub(
            amount,
            "ERC20: burn amount exceeds balance"
        );
        _totalSupply = _totalSupply.sub(amount);
        emit Transfer(account, address(0), amount);
    }

    /**
     * @dev Sets `amount` as the allowance of `spender` over the `owner`s tokens.
     *
     * This is internal function is equivalent to `approve`, and can be used to
     * e.g. set automatic allowances for certain subsystems, etc.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `owner` cannot be the zero address.
     * - `spender` cannot be the zero address.
     */
    function _approve(
        address owner,
        address spender,
        uint256 amount
    ) internal {
        require(owner != address(0), "ERC20: approve from the zero address");
        require(spender != address(0), "ERC20: approve to the zero address");

        _allowances[owner][spender] = amount;
        emit Approval(owner, spender, amount);
    }

    /**
     * @dev Destroys `amount` tokens from `account`.`amount` is then deducted
     * from the caller's allowance.
     *
     * See {_burn} and {_approve}.
     */
    function _burnFrom(address account, uint256 amount) internal {
        _burn(account, amount);
        _approve(
            account,
            _msgSender(),
            _allowances[account][_msgSender()].sub(
                amount,
                "ERC20: burn amount exceeds allowance"
            )
        );
    }
}

// File: @openzeppelin/contracts/access/Roles.sol

/**
 * @title Roles
 * @dev Library for managing addresses assigned to a Role.
 */
library Roles {
    struct Role {
        mapping(address => bool) bearer;
    }

    /**
     * @dev Give an account access to this role.
     */
    function add(Role storage role, address account) internal {
        require(!has(role, account), "Roles: account already has role");
        role.bearer[account] = true;
    }

    /**
     * @dev Remove an account's access to this role.
     */
    function remove(Role storage role, address account) internal {
        require(has(role, account), "Roles: account does not have role");
        role.bearer[account] = false;
    }

    /**
     * @dev Check if an account has this role.
     * @return bool
     */
    function has(Role storage role, address account)
        internal
        view
        returns (bool)
    {
        require(account != address(0), "Roles: account is the zero address");
        return role.bearer[account];
    }
}

// File: @openzeppelin/contracts/access/roles/MinterRole.sol

contract MinterRole is Context {
    using Roles for Roles.Role;

    event MinterAdded(address indexed account);
    event MinterRemoved(address indexed account);

    Roles.Role private _minters;

    constructor() internal {
        _addMinter(_msgSender());
    }

    modifier onlyMinter() {
        require(
            isMinter(_msgSender()),
            "MinterRole: caller does not have the Minter role"
        );
        _;
    }

    function isMinter(address account) public view returns (bool) {
        return _minters.has(account);
    }

    function addMinter(address account) public onlyMinter {
        _addMinter(account);
    }

    function renounceMinter() public {
        _removeMinter(_msgSender());
    }

    function _addMinter(address account) internal {
        _minters.add(account);
        emit MinterAdded(account);
    }

    function _removeMinter(address account) internal {
        _minters.remove(account);
        emit MinterRemoved(account);
    }
}

// File: @openzeppelin/contracts/token/ERC20/ERC20Mintable.sol

/**
 * @dev Extension of {ERC20} that adds a set of accounts with the {MinterRole},
 * which have permission to mint (create) new tokens as they see fit.
 *
 * At construction, the deployer of the contract is the only minter.
 */
contract ERC20Mintable is ERC20, MinterRole {
    /**
     * @dev See {ERC20-_mint}.
     *
     * Requirements:
     *
     * - the caller must have the {MinterRole}.
     */
    function mint(address account, uint256 amount)
        public
        onlyMinter
        returns (bool)
    {
        _mint(account, amount);
        return true;
    }
}

// File: @openzeppelin/contracts/crowdsale/emission/MintedCrowdsale.sol

/**
 * @title MintedCrowdsale
 * @dev Extension of Crowdsale contract whose tokens are minted in each purchase.
 * Token ownership should be transferred to MintedCrowdsale for minting.
 */
contract MintedCrowdsale is Crowdsale {
    /**
     * @dev Overrides delivery by minting tokens upon purchase.
     * @param beneficiary Token purchaser
     * @param tokenAmount Number of tokens to be minted
     */
    function _deliverTokens(address beneficiary, uint256 tokenAmount) internal {
        // Potentially dangerous assumption about the type of the token.
        require(
            ERC20Mintable(address(token())).mint(beneficiary, tokenAmount),
            "MintedCrowdsale: minting failed"
        );
    }
}

// File: @openzeppelin/contracts/access/roles/CapperRole.sol

contract CapperRole is Context {
    using Roles for Roles.Role;

    event CapperAdded(address indexed account);
    event CapperRemoved(address indexed account);

    Roles.Role private _cappers;

    constructor() internal {
        _addCapper(_msgSender());
    }

    modifier onlyCapper() {
        require(
            isCapper(_msgSender()),
            "CapperRole: caller does not have the Capper role"
        );
        _;
    }

    function isCapper(address account) public view returns (bool) {
        return _cappers.has(account);
    }

    function addCapper(address account) public onlyCapper {
        _addCapper(account);
    }

    function renounceCapper() public {
        _removeCapper(_msgSender());
    }

    function _addCapper(address account) internal {
        _cappers.add(account);
        emit CapperAdded(account);
    }

    function _removeCapper(address account) internal {
        _cappers.remove(account);
        emit CapperRemoved(account);
    }
}

// File: contracts/crowdsale/IndividuallyCappedCrowdsale.sol

// a single cap applied to all users

/**
 * @title IndividuallyCappedCrowdsale
 * @dev Crowdsale with per-beneficiary caps.
 */
contract IndividuallyCappedCrowdsale is Crowdsale {
    using SafeMath for uint256;

    mapping(address => uint256) private _contributions;
    // mapping(address => uint256) private _caps;
    uint256 public individualCap;

    constructor(uint256 _individualCap) public {
        individualCap = _individualCap;
    }

    /**
     * @dev Sets a specific beneficiary's maximum contribution.
     * @param beneficiary Address to be capped
     * @param cap Wei limit for individual contribution
     */
    // function setCap(address beneficiary, uint256 cap) external onlyCapper {
    //     _caps[beneficiary] = cap;
    // }

    /**
     * @dev Returns the cap of a specific beneficiary.
     * @param beneficiary Address whose cap is to be checked
     * @return Current cap for individual beneficiary
     */
    // function getCap(address beneficiary) public view returns (uint256) {
    // return _caps[beneficiary];
    // }

    /**
     * @dev Returns the amount contributed so far by a specific beneficiary.
     * @param beneficiary Address of contributor
     * @return Beneficiary contribution so far
     */
    function getContribution(address beneficiary)
        public
        view
        returns (uint256)
    {
        return _contributions[beneficiary];
    }

    /**
     * @dev Extend parent behavior requiring purchase to respect the beneficiary's funding cap.
     * @param beneficiary Token purchaser
     * @param weiAmount Amount of wei contributed
     */
    function _preValidatePurchase(address beneficiary, uint256 weiAmount)
        internal
        view
    {
        super._preValidatePurchase(beneficiary, weiAmount);
        // solhint-disable-next-line max-line-length
        // require(_contributions[beneficiary].add(weiAmount) <= _caps[beneficiary], "IndividuallyCappedCrowdsale: beneficiary's cap exceeded");
        require(
            _contributions[beneficiary].add(weiAmount) <= individualCap,
            "IndividuallyCappedCrowdsale: beneficiary's cap exceeded"
        );
    }

    /**
     * @dev Extend parent behavior to update beneficiary contributions.
     * @param beneficiary Token purchaser
     * @param weiAmount Amount of wei contributed
     */
    function _updatePurchasingState(address beneficiary, uint256 weiAmount)
        internal
    {
        super._updatePurchasingState(beneficiary, weiAmount);
        _contributions[beneficiary] = _contributions[beneficiary].add(
            weiAmount
        );
    }
}

// File: contracts/crowdsale/IncreasingPriceCrowdsale.sol

/**
 * @title IncreasingPriceCrowdsale
 * @dev Extension of Crowdsale contract that increases the price of tokens linearly in time.
 * Note that what should be provided to the constructor is the initial and final _rates_, that is,
 * the amount of tokens per wei contributed. Thus, the initial rate must be greater than the final rate.
 */
contract IncreasingPriceCrowdsale is TimedCrowdsale {
    using SafeMath for uint256;

    // uint256 private _initialRate;
    uint256 private _finalRate;

    /**
     * @dev Constructor, takes initial and final rates of tokens received per wei contributed.
     * @param finalRate Number of tokens a buyer gets per wei at the end of the crowdsale
     */
    constructor(uint256 finalRate) public {
        require(finalRate > 0, "IncreasingPriceCrowdsale: final rate is 0");
        // solhint-disable-next-line max-line-length
        _finalRate = finalRate;
    }

    /**
     * The base rate function is overridden to revert, since this crowdsale doesn't use it, and
     * all calls to it are a mistake.
     */
    function rate() public view returns (uint256) {
        revert("IncreasingPriceCrowdsale: rate() called");
    }

    // function initialRate() public view returns (uint256) {
    //     return _initialRate;
    // }

    /**
     * @return the final rate of the crowdsale.
     */
    function finalRate() public view returns (uint256) {
        return _finalRate;
    }

    /**
     * @dev Returns the rate of tokens per wei at the present time.
     * Note that, as price _increases_ with time, the rate _decreases_.
     * @return The number of tokens a buyer gets per wei at a given time
     */
    function getCurrentRate() public view returns (uint256) {
        if (!isOpen()) {
            return 0;
        }

        uint256 _weiRaised = weiRaised();
        uint256 _rate = _finalRate;

        if (_weiRaised < 15e18) {
            return _rate.mul(250).div(100);
        }
        if (_weiRaised < 30e18) {
            return _rate.mul(200).div(100);
        }
        if (_weiRaised < 45e18) {
            return _rate.mul(175).div(100);
        }
        if (_weiRaised < 75e18) {
            return _rate.mul(150).div(100);
        }
        if (_weiRaised < 105e18) {
            return _rate.mul(120).div(100);
        }
        if (_weiRaised < 135e18) {
            return _rate.mul(110).div(100);
        }
        if (_weiRaised < 175e18) {
            return _rate.mul(105).div(100);
        }
        return _rate;
    }

    /**
     * @dev Overrides parent method taking into account variable rate.
     * @param weiAmount The value in wei to be converted into tokens
     * @return The number of tokens _weiAmount wei will buy at present time
     */
    function _getTokenAmount(uint256 weiAmount)
        internal
        view
        returns (uint256)
    {
        uint256 currentRate = getCurrentRate();
        return currentRate.mul(weiAmount);
    }
}

// File: @openzeppelin/contracts/crowdsale/distribution/FinalizableCrowdsale.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, "FinalizableCrowdsale: already finalized");
        require(hasClosed(), "FinalizableCrowdsale: not closed");

        _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: contracts/crowdsale/TokenTimelock.sol

// a progressively unlocking timelock

/**
 * @dev A token holder contract that will allow a beneficiary to extract the
 * tokens after a given release time.
 *
 * Useful for simple vesting schedules like "advisors get all of their tokens
 * after 1 year".
 *
 * For a more complete vesting schedule, see {TokenVesting}.
 */
contract TokenTimelock {
    using SafeMath for uint256;
    using SafeERC20 for IERC20;

    // ERC20 basic token contract being held
    IERC20 private _token;

    // beneficiary of tokens after they are released
    address private _beneficiary;

    // timestamp when token release is enabled
    uint256 private _releaseTime;

    // timestamp when tokens were locked
    uint256 public startTime = block.timestamp;

    // how many tokens have been released so far
    uint256 public totalReleased;

    // how many tokens to lock initially
    uint256 public startLockedBalance;

    constructor(
        IERC20 token,
        address beneficiary,
        uint256 releaseTime,
        uint256 _startLockedBalance
    ) public {
        // solhint-disable-next-line not-rely-on-time
        require(
            releaseTime > block.timestamp,
            "TokenTimelock: release time is before current time"
        );
        _token = token;
        _beneficiary = beneficiary;
        _releaseTime = releaseTime;
        startLockedBalance = _startLockedBalance;
    }

    /**
     * @return the token being held.
     */
    function token() public view returns (IERC20) {
        return _token;
    }

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

    /**
     * @return the time when 100% of the tokens can be released.
     */
    function releaseTime() public view returns (uint256) {
        return _releaseTime;
    }

    // how much can be released right now
    function releasable() public view returns (uint256) {
        uint256 totalLockTime = _releaseTime.sub(startTime);
        uint256 timeElapsed = block.timestamp.sub(startTime);
        uint256 percentTimeElapsed = timeElapsed.mul(100).div(totalLockTime);
        uint256 startLockedBalanceReleasable = startLockedBalance
            .mul(percentTimeElapsed)
            .div(100);
        uint256 balanceReleasable = startLockedBalanceReleasable.sub(
            totalReleased
        );
        uint256 balance = _token.balanceOf(address(this));
        // will occur after release time has passed
        if (balanceReleasable > balance) {
            return balance;
        }
        return balanceReleasable;
    }

    /**
     * @notice Transfers tokens held by timelock to beneficiary.
     */
    function release() public {
        uint256 balanceReleasable = releasable();
        require(balanceReleasable > 0, "TokenTimelock: no tokens to release");
        totalReleased = totalReleased + balanceReleasable;
        _token.safeTransfer(_beneficiary, balanceReleasable);
    }
}

// File: contracts/crowdsale/TreasuryCrowdsale.sol

contract TreasuryCrowdsale is FinalizableCrowdsale {
    using SafeMath for uint256;

    TokenTimelock public treasuryTimelock;

    // mint treasury supply a single time after finalization (~3% unlocked, ~10% locked for 3 years)
    function _finalization() internal {
        uint256 treasuryAmountUnlocked = token().totalSupply().mul(30).div(970);
        uint256 treasuryAmountLocked = token().totalSupply().mul(100).div(900);
        treasuryTimelock = new TokenTimelock(
            token(),
            wallet(),
            block.timestamp.add(60 * 60 * 24 * 365 * 3), // 3 years
            treasuryAmountLocked
        );
        ERC20Mintable(address(token())).mint(wallet(), treasuryAmountUnlocked);
        ERC20Mintable(address(token())).mint(
            address(treasuryTimelock),
            treasuryAmountLocked
        );
        super._finalization();
    }
}

// File: contracts/Sav3Crowdsale.sol

contract Hold3rCrowdsale is
    Crowdsale,
    MintedCrowdsale,
    TimedCrowdsale,
    PostDeliveryCrowdsale,
    IndividuallyCappedCrowdsale,
    IncreasingPriceCrowdsale,
    TreasuryCrowdsale
{
    uint256 private _finalRate = 1000;
    uint256 private _individualCap = 3e18;

    constructor(
        address payable crowdsaleWallet,
        IERC20 token,
        uint256 openingTime,
        uint256 closingTime
    )
        public
        TreasuryCrowdsale()
        IncreasingPriceCrowdsale(_finalRate)
        PostDeliveryCrowdsale()
        TimedCrowdsale(openingTime, closingTime)
        IndividuallyCappedCrowdsale(_individualCap)
        MintedCrowdsale()
        Crowdsale(_finalRate, crowdsaleWallet, token)
    {}
}

{
  "compilationTarget": {
    "Hold3rCrowdsale.sol": "Hold3rCrowdsale"
  },
  "evmVersion": "istanbul",
  "libraries": {},
  "optimizer": {
    "enabled": true,
    "runs": 200
  },
  "remappings": []
}