// Sources flattened with hardhat v2.2.1 https://hardhat.org

// File @openzeppelin/contracts/utils/Context.sol@v3.4.1

// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <0.8.0;

/*
 * @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.
 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address payable) {
        return msg.sender;
    }

    function _msgData() internal view virtual 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/access/Ownable.sol@v3.4.1

// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <0.8.0;

/**
 * @dev Contract module which provides a basic access control mechanism, where
 * there is an account (an owner) that can be granted exclusive access to
 * specific functions.
 *
 * By default, the owner account will be the one that deploys the contract. This
 * can later be changed with {transferOwnership}.
 *
 * This module is used through inheritance. It will make available the modifier
 * `onlyOwner`, which can be applied to your functions to restrict their use to
 * the owner.
 */
abstract contract Ownable is Context {
    address private _owner;

    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    constructor () internal {
        address msgSender = _msgSender();
        _owner = msgSender;
        emit OwnershipTransferred(address(0), msgSender);
    }

    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view virtual returns (address) {
        return _owner;
    }

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        require(owner() == _msgSender(), "Ownable: caller is not the owner");
        _;
    }

    /**
     * @dev Leaves the contract without owner. It will not be possible to call
     * `onlyOwner` functions anymore. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby removing any functionality that is only available to the owner.
     */
    function renounceOwnership() public virtual onlyOwner {
        emit OwnershipTransferred(_owner, address(0));
        _owner = address(0);
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Can only be called by the current owner.
     */
    function transferOwnership(address newOwner) public virtual onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        emit OwnershipTransferred(_owner, newOwner);
        _owner = newOwner;
    }
}


// File contracts/Whitelist.sol

//SPDX-License-Identifier: Unlicense
pragma solidity ^0.6.1;
contract Whitelist is Ownable {

    mapping(address => bool) public whitelist;
    address[] public whitelistedAddresses;
    bool public hasWhitelisting = false;

    event AddedToWhitelist(address[] indexed accounts);
    event RemovedFromWhitelist(address indexed account);

    modifier onlyWhitelisted() {
        if(hasWhitelisting){
            require(isWhitelisted(msg.sender),"Whitelist: Not Whitelisted");
        }
        _;
    }
    
    constructor (bool _hasWhitelisting) public{
        hasWhitelisting = _hasWhitelisting;
    }

    function add(address[] memory _addresses) public onlyOwner {
        for (uint i = 0; i < _addresses.length; i++) {
            require(whitelist[_addresses[i]] != true);
            whitelist[_addresses[i]] = true;
            whitelistedAddresses.push(_addresses[i]);
        }
        emit AddedToWhitelist(_addresses);
    }

    function remove(address _address, uint256 _index) public onlyOwner {
        require(_address == whitelistedAddresses[_index]);
        whitelist[_address] = false;
        delete whitelistedAddresses[_index];
        emit RemovedFromWhitelist(_address);
    }

    function getWhitelistedAddresses() public view returns(address[] memory) {
        return whitelistedAddresses;
    } 

    function isWhitelisted(address _address) public view returns(bool) {
        return whitelist[_address];
    }
}


// File @openzeppelin/contracts/token/ERC20/IERC20.sol@v3.4.1

// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <0.8.0;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
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@v3.4.1

// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <0.8.0;

/**
 * @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, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        uint256 c = a + b;
        if (c < a) return (false, 0);
        return (true, c);
    }

    /**
     * @dev Returns the substraction of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b > a) return (false, 0);
        return (true, a - b);
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryMul(uint256 a, uint256 b) internal pure returns (bool, 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 (true, 0);
        uint256 c = a * b;
        if (c / a != b) return (false, 0);
        return (true, c);
    }

    /**
     * @dev Returns the division of two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b == 0) return (false, 0);
        return (true, a / b);
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b == 0) return (false, 0);
        return (true, a % b);
    }

    /**
     * @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) {
        require(b <= a, "SafeMath: subtraction overflow");
        return a - b;
    }

    /**
     * @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) {
        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, reverting 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) {
        require(b > 0, "SafeMath: division by zero");
        return a / b;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting 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) {
        require(b > 0, "SafeMath: modulo by zero");
        return a % b;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {trySub}.
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b <= a, errorMessage);
        return a - b;
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting with custom message on
     * division by zero. The result is rounded towards zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryDiv}.
     *
     * 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, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        return a / b;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting with custom message when dividing by zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryMod}.
     *
     * 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, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        return a % b;
    }
}


// File @openzeppelin/contracts/token/ERC20/ERC20.sol@v3.4.1

// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <0.8.0;



/**
 * @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 {ERC20PresetMinterPauser}.
 *
 * 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;

    string private _name;
    string private _symbol;
    uint8 private _decimals;

    /**
     * @dev Sets the values for {name} and {symbol}, initializes {decimals} with
     * a default value of 18.
     *
     * To select a different value for {decimals}, use {_setupDecimals}.
     *
     * All three of these values are immutable: they can only be set once during
     * construction.
     */
    constructor (string memory name_, string memory symbol_) public {
        _name = name_;
        _symbol = symbol_;
        _decimals = 18;
    }

    /**
     * @dev Returns the name of the token.
     */
    function name() public view virtual returns (string memory) {
        return _name;
    }

    /**
     * @dev Returns the symbol of the token, usually a shorter version of the
     * name.
     */
    function symbol() public view virtual returns (string memory) {
        return _symbol;
    }

    /**
     * @dev Returns the number of decimals used to get its user representation.
     * For example, if `decimals` equals `2`, a balance of `505` tokens should
     * be displayed to a user as `5,05` (`505 / 10 ** 2`).
     *
     * Tokens usually opt for a value of 18, imitating the relationship between
     * Ether and Wei. This is the value {ERC20} uses, unless {_setupDecimals} is
     * called.
     *
     * NOTE: This information is only used for _display_ purposes: it in
     * no way affects any of the arithmetic of the contract, including
     * {IERC20-balanceOf} and {IERC20-transfer}.
     */
    function decimals() public view virtual returns (uint8) {
        return _decimals;
    }

    /**
     * @dev See {IERC20-totalSupply}.
     */
    function totalSupply() public view virtual override returns (uint256) {
        return _totalSupply;
    }

    /**
     * @dev See {IERC20-balanceOf}.
     */
    function balanceOf(address account) public view virtual override 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 virtual override returns (bool) {
        _transfer(_msgSender(), recipient, amount);
        return true;
    }

    /**
     * @dev See {IERC20-allowance}.
     */
    function allowance(address owner, address spender) public view virtual override returns (uint256) {
        return _allowances[owner][spender];
    }

    /**
     * @dev See {IERC20-approve}.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function approve(address spender, uint256 amount) public virtual override 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 virtual override 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 virtual 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 virtual 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 virtual {
        require(sender != address(0), "ERC20: transfer from the zero address");
        require(recipient != address(0), "ERC20: transfer to the zero address");

        _beforeTokenTransfer(sender, recipient, amount);

        _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 virtual {
        require(account != address(0), "ERC20: mint to the zero address");

        _beforeTokenTransfer(address(0), account, amount);

        _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 virtual {
        require(account != address(0), "ERC20: burn from the zero address");

        _beforeTokenTransfer(account, address(0), amount);

        _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 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 virtual {
        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 Sets {decimals} to a value other than the default one of 18.
     *
     * WARNING: This function should only be called from the constructor. Most
     * applications that interact with token contracts will not expect
     * {decimals} to ever change, and may work incorrectly if it does.
     */
    function _setupDecimals(uint8 decimals_) internal virtual {
        _decimals = decimals_;
    }

    /**
     * @dev Hook that is called before any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
     * will be to transferred to `to`.
     * - when `from` is zero, `amount` tokens will be minted for `to`.
     * - when `to` is zero, `amount` of ``from``'s tokens will be burned.
     * - `from` and `to` are never both zero.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _beforeTokenTransfer(address from, address to, uint256 amount) internal virtual { }
}


// File @openzeppelin/contracts/utils/Pausable.sol@v3.4.1

// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <0.8.0;

/**
 * @dev Contract module which allows children to implement an emergency stop
 * mechanism that can be triggered by an authorized account.
 *
 * This module is used through inheritance. It will make available the
 * modifiers `whenNotPaused` and `whenPaused`, which can be applied to
 * the functions of your contract. Note that they will not be pausable by
 * simply including this module, only once the modifiers are put in place.
 */
abstract contract Pausable is Context {
    /**
     * @dev Emitted when the pause is triggered by `account`.
     */
    event Paused(address account);

    /**
     * @dev Emitted when the pause is lifted by `account`.
     */
    event Unpaused(address account);

    bool private _paused;

    /**
     * @dev Initializes the contract in unpaused state.
     */
    constructor () internal {
        _paused = false;
    }

    /**
     * @dev Returns true if the contract is paused, and false otherwise.
     */
    function paused() public view virtual returns (bool) {
        return _paused;
    }

    /**
     * @dev Modifier to make a function callable only when the contract is not paused.
     *
     * Requirements:
     *
     * - The contract must not be paused.
     */
    modifier whenNotPaused() {
        require(!paused(), "Pausable: paused");
        _;
    }

    /**
     * @dev Modifier to make a function callable only when the contract is paused.
     *
     * Requirements:
     *
     * - The contract must be paused.
     */
    modifier whenPaused() {
        require(paused(), "Pausable: not paused");
        _;
    }

    /**
     * @dev Triggers stopped state.
     *
     * Requirements:
     *
     * - The contract must not be paused.
     */
    function _pause() internal virtual whenNotPaused {
        _paused = true;
        emit Paused(_msgSender());
    }

    /**
     * @dev Returns to normal state.
     *
     * Requirements:
     *
     * - The contract must be paused.
     */
    function _unpause() internal virtual whenPaused {
        _paused = false;
        emit Unpaused(_msgSender());
    }
}


// File contracts/FixedSwap/FixedSwapETH.sol

//SPDX-License-Identifier: Unlicense
pragma solidity ^0.6.1;
contract FixedSwapETH is Pausable, Whitelist {
    using SafeMath for uint256;
    uint256 increment = 0;

    mapping(uint256 => Purchase) public purchases; /* Purchasers mapping */
    address[] public buyers; /* Current Buyers Addresses */
    uint256[] public purchaseIds; /* All purchaseIds */
    mapping(address => uint256[]) public myPurchases; /* Purchasers mapping */

    ERC20 public erc20;
    bool public isSaleFunded = false;
    uint public decimals = 0;
    bool public unsoldTokensReedemed = false;
    uint256 public tradeValue; /* Price in Wei */
    uint256 public startDate; /* Start Date  */
    uint256 public endDate;  /* End Date  */
    uint256 public individualMinimumAmount = 0;  /* Minimum Amount Per Address */
    uint256 public individualMaximumAmount = 0;  /* Minimum Amount Per Address */
    uint256 public minimumRaise = 0;  /* Minimum Amount of Tokens that have to be sold */
    uint256 public tokensAllocated = 0; /* Tokens Available for Allocation - Dynamic */
    uint256 public tokensForSale = 0; /* Tokens Available for Sale */
    bool    public isTokenSwapAtomic; /* Make token release atomic or not */
    address payable public FEE_ADDRESS = 0x42B78f894e826C8D6C2cd2582f32640BF8E168D4; /* Default Address for Fee Percentage */
    uint256 public feePercentage = 1; /* Default Fee 1% */

    struct Purchase {
        uint256 amount;
        address purchaser;
        uint256 ethAmount;
        uint256 timestamp;
        bool wasFinalized /* Confirm the tokens were sent already */;
        bool reverted /* Confirm the tokens were sent already */;
    }

    event PurchaseEvent(uint256 amount, address indexed purchaser, uint256 timestamp);

    constructor(address _tokenAddress, uint256 _tradeValue, uint256 _tokensForSale, uint256 _startDate, 
        uint256 _endDate, uint256 _individualMinimumAmount, uint256 _individualMaximumAmount, bool _isTokenSwapAtomic, uint256 _minimumRaise,
        uint256 _feeAmount, bool _hasWhitelisting
    ) public Whitelist(_hasWhitelisting) {
        
        /* Confirmations */
        require(block.timestamp < _endDate, "End Date should be further than current date");
        require(block.timestamp < _startDate, "Start Date should be further than current date");
        require(_startDate < _endDate, "End Date higher than Start Date");
        require(_tokensForSale > 0, "Tokens for Sale should be > 0");
        require(_tokensForSale > _individualMinimumAmount, "Tokens for Sale should be > Individual Minimum Amount");
        require(_individualMaximumAmount >= _individualMinimumAmount, "Individual Maximim AMount should be > Individual Minimum Amount");
        require(_minimumRaise <= _tokensForSale, "Minimum Raise should be < Tokens For Sale");
        require(_feeAmount >= feePercentage, "Fee Percentage has to be >= 1");
        require(_feeAmount <= 99, "Fee Percentage has to be < 100");

        startDate = _startDate; 
        endDate = _endDate;
        tokensForSale = _tokensForSale;
        tradeValue = _tradeValue;

        individualMinimumAmount = _individualMinimumAmount; 
        individualMaximumAmount = _individualMaximumAmount; 
        isTokenSwapAtomic = _isTokenSwapAtomic;

        if(!_isTokenSwapAtomic){ /* If raise is not atomic swap */
            minimumRaise = _minimumRaise;
        }

        erc20 = ERC20(_tokenAddress);
        decimals = erc20.decimals();
        feePercentage = _feeAmount;
    }

    /**
    * Modifier to make a function callable only when the contract has Atomic Swaps not available.
    */
    modifier isNotAtomicSwap() {
        require(!isTokenSwapAtomic, "Has to be non Atomic swap");
        _;
    }

     /**
    * Modifier to make a function callable only when the contract has Atomic Swaps not available.
    */
    modifier isSaleFinalized() {
        require(hasFinalized(), "Has to be finalized");
        _;
    }

     /**
    * Modifier to make a function callable only when the swap time is open.
    */
    modifier isSaleOpen() {
        require(isOpen(), "Has to be open");
        _;
    }

     /**
    * Modifier to make a function callable only when the contract has Atomic Swaps not available.
    */
    modifier isSalePreStarted() {
        require(isPreStart(), "Has to be pre-started");
        _;
    }

    /**
    * Modifier to make a function callable only when the contract has Atomic Swaps not available.
    */
    modifier isFunded() {
        require(isSaleFunded, "Has to be funded");
        _;
    }


    /* Get Functions */
    function isBuyer(uint256 purchase_id) public view returns (bool) {
        return (msg.sender == purchases[purchase_id].purchaser);
    }

    /* Get Functions */
    function totalRaiseCost() public view returns (uint256) {
        return (cost(tokensForSale));
    }

    function availableTokens() public view returns (uint256) {
        return erc20.balanceOf(address(this));
    }

    function tokensLeft() public view returns (uint256) {
        return tokensForSale - tokensAllocated;
    }

    function hasMinimumRaise() public view returns (bool){
        return (minimumRaise != 0);
    }

    /* Verify if minimum raise was not achieved */
    function minimumRaiseNotAchieved() public view returns (bool){
        require(cost(tokensAllocated) < cost(minimumRaise), "TotalRaise is bigger than minimum raise amount");
        return true;
    }

    /* Verify if minimum raise was achieved */
    function minimumRaiseAchieved() public view returns (bool){
        if(hasMinimumRaise()){
            require(cost(tokensAllocated) >= cost(minimumRaise), "TotalRaise is less than minimum raise amount");
        }
        return true;
    }

    function hasFinalized() public view returns (bool){
        return block.timestamp > endDate;
    }

    function hasStarted() public view returns (bool){
        return block.timestamp >= startDate;
    }
    
    function isPreStart() public view returns (bool){
        return block.timestamp < startDate;
    }

    function isOpen() public view returns (bool){
        return hasStarted() && !hasFinalized();
    }

    function hasMinimumAmount() public view returns (bool){
       return (individualMinimumAmount != 0);
    }
    function cost(uint256 _amount) public view returns (uint){
        return _amount.mul(tradeValue).div(10**decimals); 
    }

    function getPurchase(uint256 _purchase_id) external view returns (uint256, address, uint256, uint256, bool, bool){
        Purchase memory purchase = purchases[_purchase_id];
        return (purchase.amount, purchase.purchaser, purchase.ethAmount, purchase.timestamp, purchase.wasFinalized, purchase.reverted);
    }

    function getPurchaseIds() public view returns(uint256[] memory) {
        return purchaseIds;
    }

    function getBuyers() public view returns(address[] memory) {
        return buyers;
    }

    function getMyPurchases(address _address) public view returns(uint256[] memory) {
        return myPurchases[_address];
    }

    /* Fund - Pre Sale Start */
    function fund(uint256 _amount) public isSalePreStarted {
        
        /* Confirm transfered tokens is no more than needed */
        require(availableTokens().add(_amount) <= tokensForSale, "Transfered tokens have to be equal or less than proposed");

        /* Transfer Funds */
        require(erc20.transferFrom(msg.sender, address(this), _amount), "Failed ERC20 token transfer");
        
        /* If Amount is equal to needed - sale is ready */
        if(availableTokens() == tokensForSale){
            isSaleFunded = true;
        }
    }
    
    /* Action Functions */
    function swap(uint256 _amount) payable external whenNotPaused isFunded isSaleOpen onlyWhitelisted {

        /* Confirm Amount is positive */
        require(_amount > 0, "Amount has to be positive");

        /* Confirm Amount is less than tokens available */
        require(_amount <= tokensLeft(), "Amount is less than tokens available");
            
        /* Confirm the user has funds for the transfer, confirm the value is equal */
        require(msg.value == cost(_amount), "User has to cover the cost of the swap in ETH, use the cost function to determine");

        /* Confirm Amount is bigger than minimum Amount */
        require(_amount >= individualMinimumAmount, "Amount is bigger than minimum amount");

        /* Confirm Amount is smaller than maximum Amount */
        require(_amount <= individualMaximumAmount, "Amount is smaller than maximum amount");

        /* Verify all user purchases, loop thru them */
        uint256[] memory _purchases = getMyPurchases(msg.sender);
        uint256 purchaserTotalAmountPurchased = 0;
        for (uint i = 0; i < _purchases.length; i++) {
            Purchase memory _purchase = purchases[_purchases[i]];
            purchaserTotalAmountPurchased = purchaserTotalAmountPurchased.add(_purchase.amount);
        }
        require(purchaserTotalAmountPurchased.add(_amount) <= individualMaximumAmount, "Address has already passed the max amount of swap");

        if(isTokenSwapAtomic){
            /* Confirm transfer */
            require(erc20.transfer(msg.sender, _amount), "ERC20 transfer didn´t work");
        }
        
        uint256 purchase_id = increment;
        increment = increment.add(1);

        /* Create new purchase */
        Purchase memory purchase = Purchase(_amount, msg.sender, msg.value, block.timestamp, isTokenSwapAtomic /* If Atomic Swap */, false);
        purchases[purchase_id] = purchase;
        purchaseIds.push(purchase_id);
        myPurchases[msg.sender].push(purchase_id);
        buyers.push(msg.sender);
        tokensAllocated = tokensAllocated.add(_amount);
        emit PurchaseEvent(_amount, msg.sender, block.timestamp);
    }

    /* Redeem tokens when the sale was finalized */
    function redeemTokens(uint256 purchase_id) external isNotAtomicSwap isSaleFinalized whenNotPaused {
        /* Confirm it exists and was not finalized */
        require((purchases[purchase_id].amount != 0) && !purchases[purchase_id].wasFinalized, "Purchase is either 0 or finalized");
        require(isBuyer(purchase_id), "Address is not buyer");
        purchases[purchase_id].wasFinalized = true;
        require(erc20.transfer(msg.sender, purchases[purchase_id].amount), "ERC20 transfer failed");
    }

    /* Retrieve Minumum Amount */
    function redeemGivenMinimumGoalNotAchieved(uint256 purchase_id) external isSaleFinalized isNotAtomicSwap {
        require(hasMinimumRaise(), "Minimum raise has to exist");
        require(minimumRaiseNotAchieved(), "Minimum raise has to be reached");
        /* Confirm it exists and was not finalized */
        require((purchases[purchase_id].amount != 0) && !purchases[purchase_id].wasFinalized, "Purchase is either 0 or finalized");
        require(isBuyer(purchase_id), "Address is not buyer");
        purchases[purchase_id].wasFinalized = true;
        purchases[purchase_id].reverted = true;
        msg.sender.transfer(purchases[purchase_id].ethAmount);
    }

    /* Admin Functions */
    function withdrawFunds() external onlyOwner whenNotPaused isSaleFinalized {
        require(minimumRaiseAchieved(), "Minimum raise has to be reached");
        FEE_ADDRESS.transfer(address(this).balance.mul(feePercentage).div(100)); /* Fee Address */
        msg.sender.transfer(address(this).balance);
    }  
    
    function withdrawUnsoldTokens() external onlyOwner isSaleFinalized {
        require(!unsoldTokensReedemed);
        uint256 unsoldTokens;
        if(hasMinimumRaise() && 
            (cost(tokensAllocated) < cost(minimumRaise))){ /* Minimum Raise not reached */
                unsoldTokens = tokensForSale;
        }else{
            /* If minimum Raise Achieved Redeem All Tokens minus the ones */
            unsoldTokens = tokensForSale.sub(tokensAllocated);
        }

        if(unsoldTokens > 0){
            unsoldTokensReedemed = true;
            require(erc20.transfer(msg.sender, unsoldTokens), "ERC20 transfer failed");
        }
    }   

    function removeOtherERC20Tokens(address _tokenAddress, address _to) external onlyOwner isSaleFinalized {
        require(_tokenAddress != address(erc20), "Token Address has to be diff than the erc20 subject to sale"); // Confirm tokens addresses are different from main sale one
        ERC20 erc20Token = ERC20(_tokenAddress);
        require(erc20Token.transfer(_to, erc20Token.balanceOf(address(this))), "ERC20 Token transfer failed");
    } 

    /* Safe Pull function */
    function safePull() payable external onlyOwner whenPaused {
        msg.sender.transfer(address(this).balance);
        erc20.transfer(msg.sender, erc20.balanceOf(address(this)));
    }
}