// File: contracts/common/VirtualBalanceWrapperFactory.sol



// SPDX-License-Identifier: UNLICENSED
/* 

  _                          _   _____   _                       
 | |       ___   _ __     __| | |  ___| | |   __ _   _ __    ___ 
 | |      / _ \ | '_ \   / _` | | |_    | |  / _` | | '__|  / _ \
 | |___  |  __/ | | | | | (_| | |  _|   | | | (_| | | |    |  __/
 |_____|  \___| |_| |_|  \__,_| |_|     |_|  \__,_| |_|     \___|
                                                                 
LendFlare.finance
*/

pragma solidity =0.6.12;

import "@openzeppelin/contracts/math/SafeMath.sol";

contract VirtualBalanceWrapper {
    using SafeMath for uint256;

    address public owner;
    uint256 private _totalSupply;
    mapping(address => uint256) private _balances;

    constructor(address _owner) public {
        owner = _owner;
    }

    function totalSupply() public view returns (uint256) {
        return _totalSupply;
    }

    function balanceOf(address _for) public view returns (uint256) {
        return _balances[_for];
    }

    function stakeFor(address _for, uint256 _amount) public returns (bool) {
        require(
            msg.sender == owner,
            "VirtualBalanceWrapper: !authorized stakeFor"
        );
        require(_amount > 0, "VirtualBalanceWrapper: !_amount");

        _totalSupply = _totalSupply.add(_amount);
        _balances[_for] = _balances[_for].add(_amount);

        return true;
    }

    function withdrawFor(address _for, uint256 _amount) public returns (bool) {
        require(
            msg.sender == owner,
            "VirtualBalanceWrapper: !authorized withdrawFor"
        );
        require(_amount > 0, "VirtualBalanceWrapper: !_amount");

        _totalSupply = _totalSupply.sub(_amount);
        _balances[_for] = _balances[_for].sub(_amount);

        return true;
    }
}

contract VirtualBalanceWrapperFactory {
    event NewOwner(address indexed sender, address operator);
    event RemoveOwner(address indexed sender, address operator);

    mapping(address => bool) private owners;

    modifier onlyOwners() {
        require(isOwner(msg.sender), "vbw: caller is not an owner onlyOwners");
        _;
    }

    constructor() public {
        owners[msg.sender] = true;
    }

    function addOwner(address _newOwner) public onlyOwners {
        require(!isOwner(_newOwner), "vbw: address is already owner addOwner");

        owners[_newOwner] = true;

        emit NewOwner(msg.sender, _newOwner);
    }

    function addOwners(address[] calldata _newOwners) external onlyOwners {
        for (uint256 i = 0; i < _newOwners.length; i++) {
            addOwner(_newOwners[i]);
        }
    }

    function removeOwner(address _owner) external onlyOwners {
        require(isOwner(_owner), "vbw: address is not owner removeOwner");

        owners[_owner] = false;

        emit RemoveOwner(msg.sender, _owner);
    }

    function isOwner(address _owner) public view returns (bool) {
        return owners[_owner];
    }

    function createWrapper(address _owner) public onlyOwners returns (address) {
        return address(new VirtualBalanceWrapper(_owner));
    }
}

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



// 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;
    }
}