// File: @openzeppelin/contracts/token/ERC20/IERC20.sol

pragma solidity ^0.5.0;

/**
 * @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/token/ERC20/ERC20Detailed.sol

pragma solidity ^0.5.0;


/**
 * @dev Optional functions from the ERC20 standard.
 */
contract ERC20Detailed is IERC20 {
    string private _name;
    string private _symbol;
    uint8 private _decimals;

    /**
     * @dev Sets the values for `name`, `symbol`, and `decimals`. All three of
     * these values are immutable: they can only be set once during
     * construction.
     */
    constructor (string memory name, string memory symbol, uint8 decimals) public {
        _name = name;
        _symbol = symbol;
        _decimals = decimals;
    }

    /**
     * @dev Returns the name of the token.
     */
    function name() public view returns (string memory) {
        return _name;
    }

    /**
     * @dev Returns the symbol of the token, usually a shorter version of the
     * name.
     */
    function symbol() public view 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.
     *
     * 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 returns (uint8) {
        return _decimals;
    }
}

// File: @openzeppelin/contracts/GSN/Context.sol

pragma solidity ^0.5.0;

/*
 * @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.
 */
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/math/SafeMath.sol

pragma solidity ^0.5.0;

/**
 * @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, 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/token/ERC20/ERC20.sol

pragma solidity ^0.5.0;




/**
 * @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 {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

pragma solidity ^0.5.0;

/**
 * @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/PauserRole.sol

pragma solidity ^0.5.0;



contract PauserRole is Context {
    using Roles for Roles.Role;

    event PauserAdded(address indexed account);
    event PauserRemoved(address indexed account);

    Roles.Role private _pausers;

    constructor () internal {
        _addPauser(_msgSender());
    }

    modifier onlyPauser() {
        require(isPauser(_msgSender()), "PauserRole: caller does not have the Pauser role");
        _;
    }

    function isPauser(address account) public view returns (bool) {
        return _pausers.has(account);
    }

    function addPauser(address account) public onlyPauser {
        _addPauser(account);
    }

    function renouncePauser() public {
        _removePauser(_msgSender());
    }

    function _addPauser(address account) internal {
        _pausers.add(account);
        emit PauserAdded(account);
    }

    function _removePauser(address account) internal {
        _pausers.remove(account);
        emit PauserRemoved(account);
    }
}

// File: @openzeppelin/contracts/lifecycle/Pausable.sol

pragma solidity ^0.5.0;



/**
 * @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.
 */
contract Pausable is Context, PauserRole {
    /**
     * @dev Emitted when the pause is triggered by a pauser (`account`).
     */
    event Paused(address account);

    /**
     * @dev Emitted when the pause is lifted by a pauser (`account`).
     */
    event Unpaused(address account);

    bool private _paused;

    /**
     * @dev Initializes the contract in unpaused state. Assigns the Pauser role
     * to the deployer.
     */
    constructor () internal {
        _paused = false;
    }

    /**
     * @dev Returns true if the contract is paused, and false otherwise.
     */
    function paused() public view returns (bool) {
        return _paused;
    }

    /**
     * @dev Modifier to make a function callable only when the contract is not paused.
     */
    modifier whenNotPaused() {
        require(!_paused, "Pausable: paused");
        _;
    }

    /**
     * @dev Modifier to make a function callable only when the contract is paused.
     */
    modifier whenPaused() {
        require(_paused, "Pausable: not paused");
        _;
    }

    /**
     * @dev Called by a pauser to pause, triggers stopped state.
     */
    function pause() public onlyPauser whenNotPaused {
        _paused = true;
        emit Paused(_msgSender());
    }

    /**
     * @dev Called by a pauser to unpause, returns to normal state.
     */
    function unpause() public onlyPauser whenPaused {
        _paused = false;
        emit Unpaused(_msgSender());
    }
}

// File: @openzeppelin/contracts/token/ERC20/ERC20Pausable.sol

pragma solidity ^0.5.0;



/**
 * @title Pausable token
 * @dev ERC20 with pausable transfers and allowances.
 *
 * Useful if you want to stop trades until the end of a crowdsale, or have
 * an emergency switch for freezing all token transfers in the event of a large
 * bug.
 */
contract ERC20Pausable is ERC20, Pausable {
    function transfer(address to, uint256 value) public whenNotPaused returns (bool) {
        return super.transfer(to, value);
    }

    function transferFrom(address from, address to, uint256 value) public whenNotPaused returns (bool) {
        return super.transferFrom(from, to, value);
    }

    function approve(address spender, uint256 value) public whenNotPaused returns (bool) {
        return super.approve(spender, value);
    }

    function increaseAllowance(address spender, uint256 addedValue) public whenNotPaused returns (bool) {
        return super.increaseAllowance(spender, addedValue);
    }

    function decreaseAllowance(address spender, uint256 subtractedValue) public whenNotPaused returns (bool) {
        return super.decreaseAllowance(spender, subtractedValue);
    }
}

// File: @openzeppelin/contracts/access/roles/WhitelistAdminRole.sol

pragma solidity ^0.5.0;



/**
 * @title WhitelistAdminRole
 * @dev WhitelistAdmins are responsible for assigning and removing Whitelisted accounts.
 */
contract WhitelistAdminRole is Context {
    using Roles for Roles.Role;

    event WhitelistAdminAdded(address indexed account);
    event WhitelistAdminRemoved(address indexed account);

    Roles.Role private _whitelistAdmins;

    constructor () internal {
        _addWhitelistAdmin(_msgSender());
    }

    modifier onlyWhitelistAdmin() {
        require(isWhitelistAdmin(_msgSender()), "WhitelistAdminRole: caller does not have the WhitelistAdmin role");
        _;
    }

    function isWhitelistAdmin(address account) public view returns (bool) {
        return _whitelistAdmins.has(account);
    }

    function addWhitelistAdmin(address account) public onlyWhitelistAdmin {
        _addWhitelistAdmin(account);
    }

    function renounceWhitelistAdmin() public {
        _removeWhitelistAdmin(_msgSender());
    }

    function _addWhitelistAdmin(address account) internal {
        _whitelistAdmins.add(account);
        emit WhitelistAdminAdded(account);
    }

    function _removeWhitelistAdmin(address account) internal {
        _whitelistAdmins.remove(account);
        emit WhitelistAdminRemoved(account);
    }
}

// File: @openzeppelin/contracts/access/roles/WhitelistedRole.sol

pragma solidity ^0.5.0;




/**
 * @title WhitelistedRole
 * @dev Whitelisted accounts have been approved by a WhitelistAdmin to perform certain actions (e.g. participate in a
 * crowdsale). This role is special in that the only accounts that can add it are WhitelistAdmins (who can also remove
 * it), and not Whitelisteds themselves.
 */
contract WhitelistedRole is Context, WhitelistAdminRole {
    using Roles for Roles.Role;

    event WhitelistedAdded(address indexed account);
    event WhitelistedRemoved(address indexed account);

    Roles.Role private _whitelisteds;

    modifier onlyWhitelisted() {
        require(isWhitelisted(_msgSender()), "WhitelistedRole: caller does not have the Whitelisted role");
        _;
    }

    function isWhitelisted(address account) public view returns (bool) {
        return _whitelisteds.has(account);
    }

    function addWhitelisted(address account) public onlyWhitelistAdmin {
        _addWhitelisted(account);
    }

    function removeWhitelisted(address account) public onlyWhitelistAdmin {
        _removeWhitelisted(account);
    }

    function renounceWhitelisted() public {
        _removeWhitelisted(_msgSender());
    }

    function _addWhitelisted(address account) internal {
        _whitelisteds.add(account);
        emit WhitelistedAdded(account);
    }

    function _removeWhitelisted(address account) internal {
        _whitelisteds.remove(account);
        emit WhitelistedRemoved(account);
    }
}

// File: contracts/ERC1132.sol

pragma solidity ^0.5.6;

/**
 * @title ERC1132 interface
 * @dev see https://github.com/ethereum/EIPs/issues/1132
 */

contract ERC1132 {
    /**
     * @dev Reasons why a user's tokens have been locked
     */
    mapping(address => bytes32[]) public lockReason;

    /**
     * @dev locked token structure
     */
    struct lockToken {
        uint256 amount;
        uint256 validity;
        bool claimed;
    }

    /**
     * @dev Holds number & validity of tokens locked for a given reason for
     *      a specified address
     */
    mapping(address => mapping(bytes32 => lockToken)) public locked;

    /**
     * @dev Records data of all the tokens Locked
     */
    event Locked(
        address indexed _of,
        bytes32 indexed _reason,
        uint256 _amount,
        uint256 _validity
    );

    /**
     * @dev Records data of all the tokens unlocked
     */
    event Unlocked(
        address indexed _of,
        bytes32 indexed _reason,
        uint256 _amount
    );

    /**
     * @dev Locks a specified amount of tokens against an address,
     *      for a specified reason and time
     * @param _reason The reason to lock tokens
     * @param _amount Number of tokens to be locked
     * @param _time Lock time in seconds
     */
    function lock(bytes32 _reason, uint256 _amount, uint256 _time)
        public returns (bool);

    /**
     * @dev Returns tokens locked for a specified address for a
     *      specified reason
     *
     * @param _of The address whose tokens are locked
     * @param _reason The reason to query the lock tokens for
     */
    function tokensLocked(address _of, bytes32 _reason)
        public view returns (uint256 amount);

    /**
     * @dev Returns tokens locked for a specified address for a
     *      specified reason at a specific time
     *
     * @param _of The address whose tokens are locked
     * @param _reason The reason to query the lock tokens for
     * @param _time The timestamp to query the lock tokens for
     */
    function tokensLockedAtTime(address _of, bytes32 _reason, uint256 _time)
        public view returns (uint256 amount);

    /**
     * @dev Returns total tokens held by an address (locked + transferable)
     * @param _of The address to query the total balance of
     */
    function totalBalanceOf(address _of)
        public view returns (uint256 amount);

    /**
     * @dev Extends lock for a specified reason and time
     * @param _reason The reason to lock tokens
     * @param _time Lock extension time in seconds
     */
    function extendLock(bytes32 _reason, uint256 _time)
        public returns (bool);

    /**
     * @dev Increase number of tokens locked for a specified reason
     * @param _reason The reason to lock tokens
     * @param _amount Number of tokens to be increased
     */
    function increaseLockAmount(bytes32 _reason, uint256 _amount)
        public returns (bool);

    /**
     * @dev Returns unlockable tokens for a specified address for a specified reason
     * @param _of The address to query the the unlockable token count of
     * @param _reason The reason to query the unlockable tokens for
     */
    function tokensUnlockable(address _of, bytes32 _reason)
        public view returns (uint256 amount);

    /**
     * @dev Unlocks the unlockable tokens of a specified address
     * @param _of Address of user, claiming back unlockable tokens
     */
    function unlock(address _of)
        public returns (uint256 unlockableTokens);

    /**
     * @dev Gets the unlockable tokens of a specified address
     * @param _of The address to query the the unlockable token count of
     */
    function getUnlockableTokens(address _of)
        public view returns (uint256 unlockableTokens);

}

// File: contracts/SDC.sol

pragma solidity ^0.5.6;





/// @title SDC - ERC20 token. Utility coin
/// @notice Implementation for the ERC-1132 lockable token
contract SDC is ERC1132, ERC20Detailed, ERC20Pausable, WhitelistedRole {

  /**
    * @dev Error messages for require statements
    */
    string internal constant ALREADY_LOCKED = 'Tokens already locked';
    string internal constant NOT_LOCKED = 'No tokens locked';
    string internal constant AMOUNT_ZERO = 'Amount can not be 0';

  /**
    * @dev Token issue information
    */
    string private NAME = 'SDPlatform SDC Token';
    string private SYMBOL = 'SDC';
    uint8 private DECIMALS = 18;
    uint256 private INITIAL_SUPPLY = 3500000000;

    constructor() public ERC20Detailed(NAME, SYMBOL, DECIMALS) {
        _mint(msg.sender, INITIAL_SUPPLY * (10 ** uint(DECIMALS)));
        _addWhitelisted(msg.sender);
    }

    /// @notice Mints amount of SDC on account
    /// Can be used only by whitelist
    function mint(address _account, uint256 _amount) external
    whenNotPaused onlyWhitelisted {
        _mint(_account, _amount);
    }

    /// @notice Burns amount of SDC from account and removes
    /// allowance for this amount
    /// Can be used only by whitelist
    function burnFrom(address _account, uint256 _amount) external
    whenNotPaused onlyWhitelisted {
        _burnFrom(_account, _amount);
    }

    // @notice Add Whitelisted Role of SDC on account
    /// Can be used only by whitelist
    function addWhitelisted(address _account) public
    whenNotPaused onlyWhitelistAdmin {
        _addWhitelisted(_account);
    }

    // @notice Remove Whitelisted Role of SDC on account
    /// Can be used only by whitelist
    function removeWhitelisted(address _account) public
    whenNotPaused onlyWhitelistAdmin {
        _removeWhitelisted(_account);
    }

    /**
     * @dev Locks a specified amount of tokens against an address,
     *      for a specified reason and time
     * @param _reason The reason to lock tokens
     * @param _amount Number of tokens to be locked
     * @param _time Lock time in seconds
     */
    function lock(bytes32 _reason, uint256 _amount, uint256 _time) public
    whenNotPaused onlyWhitelisted returns (bool) {
        uint256 validUntil = now.add(_time);

        // If tokens are already locked, then functions extendLock or
        // increaseLockAmount should be used to make any changes
        require(tokensLocked(msg.sender, _reason) == 0, ALREADY_LOCKED);
        require(_amount != 0, AMOUNT_ZERO);

        if (locked[msg.sender][_reason].amount == 0)
            lockReason[msg.sender].push(_reason);

        transfer(address(this), _amount);

        locked[msg.sender][_reason] = lockToken(_amount, validUntil, false);

        emit Locked(msg.sender, _reason, _amount, validUntil);
        return true;
    }

    /**
     * @dev Transfers and Locks a specified amount of tokens,
     *      for a specified reason and time
     * @param _to adress to which tokens are to be transfered
     * @param _reason The reason to lock tokens
     * @param _amount Number of tokens to be transfered and locked
     * @param _time Lock time in seconds
     */
    function transferWithLock(address _to, bytes32 _reason, uint256 _amount, uint256 _time) public
    whenNotPaused onlyWhitelisted returns (bool) {
        uint256 validUntil = now.add(_time);

        require(tokensLocked(_to, _reason) == 0, ALREADY_LOCKED);
        require(_amount != 0, AMOUNT_ZERO);

        if (locked[_to][_reason].amount == 0)
            lockReason[_to].push(_reason);

        transfer(address(this), _amount);

        locked[_to][_reason] = lockToken(_amount, validUntil, false);

        emit Locked(_to, _reason, _amount, validUntil);
        return true;
    }

    /**
     * @dev Returns tokens locked for a specified address for a
     *      specified reason
     *
     * @param _of The address whose tokens are locked
     * @param _reason The reason to query the lock tokens for
     */
    function tokensLocked(address _of, bytes32 _reason) public view
    whenNotPaused onlyWhitelisted returns (uint256 amount) {
        if (!locked[_of][_reason].claimed)
            amount = locked[_of][_reason].amount;
    }

    /**
     * @dev Returns tokens locked for a specified address for a
     *      specified reason at a specific time
     *
     * @param _of The address whose tokens are locked
     * @param _reason The reason to query the lock tokens for
     * @param _time The timestamp to query the lock tokens for
     */
    function tokensLockedAtTime(address _of, bytes32 _reason, uint256 _time) public view
    whenNotPaused onlyWhitelisted returns (uint256 amount) {
        if (locked[_of][_reason].validity > _time)
            amount = locked[_of][_reason].amount;
    }

    /**
     * @dev Returns total tokens held by an address (locked + transferable)
     * @param _of The address to query the total balance of
     */
    function totalBalanceOf(address _of) public view
    whenNotPaused onlyWhitelisted returns (uint256 amount) {
        amount = balanceOf(_of);

        for (uint256 i = 0; i < lockReason[_of].length; i++) {
            amount = amount.add(tokensLocked(_of, lockReason[_of][i]));
        }
    }

    /**
     * @dev Extends lock for a specified reason and time
     * @param _reason The reason to lock tokens
     * @param _time Lock extension time in seconds
     */
    function extendLock(bytes32 _reason, uint256 _time) public
    whenNotPaused onlyWhitelisted returns (bool) {
        require(tokensLocked(msg.sender, _reason) > 0, NOT_LOCKED);

        locked[msg.sender][_reason].validity = locked[msg.sender][_reason].validity.add(_time);

        emit Locked(msg.sender, _reason, locked[msg.sender][_reason].amount, locked[msg.sender][_reason].validity);
        return true;
    }

    /**
     * @dev Increase number of tokens locked for a specified reason
     * @param _reason The reason to lock tokens
     * @param _amount Number of tokens to be increased
     */
    function increaseLockAmount(bytes32 _reason, uint256 _amount) public
    whenNotPaused onlyWhitelisted returns (bool) {
        require(tokensLocked(msg.sender, _reason) > 0, NOT_LOCKED);
        transfer(address(this), _amount);

        locked[msg.sender][_reason].amount = locked[msg.sender][_reason].amount.add(_amount);

        emit Locked(msg.sender, _reason, locked[msg.sender][_reason].amount, locked[msg.sender][_reason].validity);
        return true;
    }

    /**
     * @dev Returns unlockable tokens for a specified address for a specified reason
     * @param _of The address to query the the unlockable token count of
     * @param _reason The reason to query the unlockable tokens for
     */
    function tokensUnlockable(address _of, bytes32 _reason) public view
    whenNotPaused onlyWhitelisted returns (uint256 amount) {
        if (locked[_of][_reason].validity <= now && !locked[_of][_reason].claimed)
            amount = locked[_of][_reason].amount;
    }

    /**
     * @dev Unlocks the unlockable tokens of a specified address
     * @param _of Address of user, claiming back unlockable tokens
     */
    function unlock(address _of) public
    whenNotPaused onlyWhitelisted returns (uint256 unlockableTokens) {
        uint256 lockedTokens;

        for (uint256 i = 0; i < lockReason[_of].length; i++) {
            lockedTokens = tokensUnlockable(_of, lockReason[_of][i]);
            if (lockedTokens > 0) {
                unlockableTokens = unlockableTokens.add(lockedTokens);
                locked[_of][lockReason[_of][i]].claimed = true;
                emit Unlocked(_of, lockReason[_of][i], lockedTokens);
            }
        }

        if (unlockableTokens > 0)
            this.transfer(_of, unlockableTokens);
    }

    /**
     * @dev Gets the unlockable tokens of a specified address
     * @param _of The address to query the the unlockable token count of
     */
    function getUnlockableTokens(address _of) public view
    whenNotPaused onlyWhitelisted returns (uint256 unlockableTokens) {
        uint256 lockedTokens;

        for (uint256 i = 0; i < lockReason[_of].length; i++) {
            lockedTokens = tokensUnlockable(_of, lockReason[_of][i]);
            unlockableTokens = unlockableTokens.add(lockedTokens);
        }
    }
}