/**
 * Copyright 2017-2019, bZeroX, LLC. All Rights Reserved.
 * Licensed under the Apache License, Version 2.0.
 */
 
pragma solidity 0.5.8;


/**
 * @title ERC20Basic
 * @dev Simpler version of ERC20 interface
 * See https://github.com/ethereum/EIPs/issues/179
 */
contract ERC20Basic {
  function totalSupply() public view returns (uint256);
  function balanceOf(address _who) public view returns (uint256);
  function transfer(address _to, uint256 _value) public returns (bool);
  event Transfer(address indexed from, address indexed to, uint256 value);
}

/**
 * @title ERC20 interface
 * @dev see https://github.com/ethereum/EIPs/issues/20
 */
contract ERC20 is ERC20Basic {
  function allowance(address _owner, address _spender)
    public view returns (uint256);

  function transferFrom(address _from, address _to, uint256 _value)
    public returns (bool);

  function approve(address _spender, uint256 _value) public returns (bool);
  event Approval(
    address indexed owner,
    address indexed spender,
    uint256 value
  );
}

contract WETHInterface is ERC20 {
    function deposit() external payable;
    function withdraw(uint256 wad) external;
}

/**
 * @title SafeMath
 * @dev Math operations with safety checks that throw on error
 */
library SafeMath {

  /**
  * @dev Multiplies two numbers, throws on overflow.
  */
  function mul(uint256 _a, uint256 _b) internal pure returns (uint256 c) {
    // Gas optimization: this is cheaper than asserting 'a' not being zero, but the
    // benefit is lost if 'b' is also tested.
    // See: https://github.com/OpenZeppelin/openzeppelin-solidity/pull/522
    if (_a == 0) {
      return 0;
    }

    c = _a * _b;
    assert(c / _a == _b);
    return c;
  }

  /**
  * @dev Integer division of two numbers, truncating the quotient.
  */
  function div(uint256 _a, uint256 _b) internal pure returns (uint256) {
    // assert(_b > 0); // Solidity automatically throws when dividing by 0
    // uint256 c = _a / _b;
    // assert(_a == _b * c + _a % _b); // There is no case in which this doesn't hold
    return _a / _b;
  }

  /**
  * @dev Integer division of two numbers, rounding up and truncating the quotient
  */
  function divCeil(uint256 _a, uint256 _b) internal pure returns (uint256) {
    if (_a == 0) {
      return 0;
    }

    return ((_a - 1) / _b) + 1;
  }

  /**
  * @dev Subtracts two numbers, throws on overflow (i.e. if subtrahend is greater than minuend).
  */
  function sub(uint256 _a, uint256 _b) internal pure returns (uint256) {
    assert(_b <= _a);
    return _a - _b;
  }

  /**
  * @dev Adds two numbers, throws on overflow.
  */
  function add(uint256 _a, uint256 _b) internal pure returns (uint256 c) {
    c = _a + _b;
    assert(c >= _a);
    return c;
  }
}

/**
 * @title Ownable
 * @dev The Ownable contract has an owner address, and provides basic authorization control
 * functions, this simplifies the implementation of "user permissions".
 */
contract Ownable {
  address public owner;


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


  /**
   * @dev The Ownable constructor sets the original `owner` of the contract to the sender
   * account.
   */
  constructor() public {
    owner = msg.sender;
  }

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

  /**
   * @dev Allows the current owner to transfer control of the contract to a newOwner.
   * @param _newOwner The address to transfer ownership to.
   */
  function transferOwnership(address _newOwner) public onlyOwner {
    _transferOwnership(_newOwner);
  }

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

/**
 * @title Helps contracts guard against reentrancy attacks.
 * @author Remco Bloemen <remco@2π.com>, Eenae <[email protected]>
 * @dev If you mark a function `nonReentrant`, you should also
 * mark it `external`.
 */
contract ReentrancyGuard {

  /// @dev Constant for unlocked guard state - non-zero to prevent extra gas costs.
  /// See: https://github.com/OpenZeppelin/openzeppelin-solidity/issues/1056
  uint256 internal constant REENTRANCY_GUARD_FREE = 1;

  /// @dev Constant for locked guard state
  uint256 internal constant REENTRANCY_GUARD_LOCKED = 2;

  /**
   * @dev We use a single lock for the whole contract.
   */
  uint256 internal reentrancyLock = REENTRANCY_GUARD_FREE;

  /**
   * @dev Prevents a contract from calling itself, directly or indirectly.
   * If you mark a function `nonReentrant`, you should also
   * mark it `external`. Calling one `nonReentrant` function from
   * another is not supported. Instead, you can implement a
   * `private` function doing the actual work, and an `external`
   * wrapper marked as `nonReentrant`.
   */
  modifier nonReentrant() {
    require(reentrancyLock == REENTRANCY_GUARD_FREE, "nonReentrant");
    reentrancyLock = REENTRANCY_GUARD_LOCKED;
    _;
    reentrancyLock = REENTRANCY_GUARD_FREE;
  }

}

contract LoanTokenization is ReentrancyGuard, Ownable {

    uint256 internal constant MAX_UINT = 2**256 - 1;

    string public name;
    string public symbol;
    uint8 public decimals;

    address public bZxContract;
    address public bZxVault;
    address public bZxOracle;
    address public wethContract;

    address public loanTokenAddress;

    // price of token at last user checkpoint
    mapping (address => uint256) internal checkpointPrices_;
}

contract LoanTokenStorage is LoanTokenization {

    struct ListIndex {
        uint256 index;
        bool isSet;
    }

    struct LoanData {
        bytes32 loanOrderHash;
        uint256 leverageAmount;
        uint256 initialMarginAmount;
        uint256 maintenanceMarginAmount;
        uint256 maxDurationUnixTimestampSec;
        uint256 index;
    }

    struct TokenReserves {
        address lender;
        uint256 amount;
    }

    event Borrow(
        address indexed borrower,
        uint256 borrowAmount,
        uint256 interestRate,
        address collateralTokenAddress,
        address tradeTokenToFillAddress,
        bool withdrawOnOpen
    );

    event Claim(
        address indexed claimant,
        uint256 tokenAmount,
        uint256 assetAmount,
        uint256 remainingTokenAmount,
        uint256 price
    );

    bool internal isInitialized_ = false;

    address public tokenizedRegistry;

    uint256 public baseRate = 1000000000000000000; // 1.0%
    uint256 public rateMultiplier = 39000000000000000000; // 39%

    // "fee percentage retained by the oracle" = SafeMath.sub(10**20, spreadMultiplier);
    uint256 public spreadMultiplier;

    mapping (uint256 => bytes32) public loanOrderHashes; // mapping of levergeAmount to loanOrderHash
    mapping (bytes32 => LoanData) public loanOrderData; // mapping of loanOrderHash to LoanOrder
    uint256[] public leverageList;

    TokenReserves[] public burntTokenReserveList; // array of TokenReserves
    mapping (address => ListIndex) public burntTokenReserveListIndex; // mapping of lender address to ListIndex objects
    uint256 public burntTokenReserved; // total outstanding burnt token amount
    address internal nextOwedLender_;

    uint256 public totalAssetBorrow = 0; // current amount of loan token amount tied up in loans

    uint256 internal checkpointSupply_;

    uint256 internal lastSettleTime_;

    uint256 public initialPrice;
}

contract AdvancedTokenStorage is LoanTokenStorage {
    using SafeMath for uint256;

    event Transfer(
        address indexed from,
        address indexed to,
        uint256 value
    );
    event Approval(
        address indexed owner,
        address indexed spender,
        uint256 value
    );
    event Mint(
        address indexed minter,
        uint256 tokenAmount,
        uint256 assetAmount,
        uint256 price
    );
    event Burn(
        address indexed burner,
        uint256 tokenAmount,
        uint256 assetAmount,
        uint256 price
    );

    mapping(address => uint256) internal balances;
    mapping (address => mapping (address => uint256)) internal allowed;
    uint256 internal totalSupply_;

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

    function balanceOf(
        address _owner)
        public
        view
        returns (uint256)
    {
        return balances[_owner];
    }

    function allowance(
        address _owner,
        address _spender)
        public
        view
        returns (uint256)
    {
        return allowed[_owner][_spender];
    }
}

contract LoanToken is AdvancedTokenStorage {

    address internal target_;

    constructor(
        address _newTarget)
        public
    {
        _setTarget(_newTarget);
    }

    function()
        external
        payable
    {
        address target = target_;
        bytes memory data = msg.data;
        assembly {
            let result := delegatecall(gas, target, add(data, 0x20), mload(data), 0, 0)
            let size := returndatasize
            let ptr := mload(0x40)
            returndatacopy(ptr, 0, size)
            switch result
            case 0 { revert(ptr, size) }
            default { return(ptr, size) }
        }
    }

    function setTarget(
        address _newTarget)
        public
        onlyOwner
    {
        _setTarget(_newTarget);
    }

    function _setTarget(
        address _newTarget)
        internal
    {
        require(_isContract(_newTarget), "target not a contract");
        target_ = _newTarget;
    }

    function _isContract(
        address addr)
        internal
        view
        returns (bool)
    {
        uint256 size;
        assembly { size := extcodesize(addr) }
        return size > 0;
    }
}

/**
 * Copyright 2017–2019, bZeroX, LLC. All Rights Reserved.
 * Licensed under the Apache License, Version 2.0.
 */
 
pragma solidity 0.5.2;


/**
 * @title Ownable
 * @dev The Ownable contract has an owner address, and provides basic authorization control
 * functions, this simplifies the implementation of "user permissions".
 */
contract Ownable {
  address public owner;


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


  /**
   * @dev The Ownable constructor sets the original `owner` of the contract to the sender
   * account.
   */
  constructor() public {
    owner = msg.sender;
  }

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

  /**
   * @dev Allows the current owner to relinquish control of the contract.
   * @notice Renouncing to ownership will leave the contract without an owner.
   * It will not be possible to call the functions with the `onlyOwner`
   * modifier anymore.
   */
  function renounceOwnership() public onlyOwner {
    emit OwnershipRenounced(owner);
    owner = address(0);
  }

  /**
   * @dev Allows the current owner to transfer control of the contract to a newOwner.
   * @param _newOwner The address to transfer ownership to.
   */
  function transferOwnership(address _newOwner) public onlyOwner {
    _transferOwnership(_newOwner);
  }

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

contract BZxOwnable is Ownable {

    address public bZxContractAddress;

    event BZxOwnershipTransferred(address indexed previousBZxContract, address indexed newBZxContract);

    // modifier reverts if bZxContractAddress isn't set
    modifier onlyBZx() {
        require(msg.sender == bZxContractAddress, "only bZx contracts can call this function");
        _;
    }

    /**
    * @dev Allows the current owner to transfer the bZx contract owner to a new contract address
    * @param newBZxContractAddress The bZx contract address to transfer ownership to.
    */
    function transferBZxOwnership(address newBZxContractAddress) public onlyOwner {
        require(newBZxContractAddress != address(0) && newBZxContractAddress != owner, "transferBZxOwnership::unauthorized");
        emit BZxOwnershipTransferred(bZxContractAddress, newBZxContractAddress);
        bZxContractAddress = newBZxContractAddress;
    }

    /**
    * @dev Allows the current owner to transfer control of the contract to a newOwner.
    * @param newOwner The address to transfer ownership to.
    * This overrides transferOwnership in Ownable to prevent setting the new owner the same as the bZxContract
    */
    function transferOwnership(address newOwner) public onlyOwner {
        require(newOwner != address(0) && newOwner != bZxContractAddress, "transferOwnership::unauthorized");
        emit OwnershipTransferred(owner, newOwner);
        owner = newOwner;
    }
}

interface NonCompliantEIP20 {
    function transfer(address _to, uint256 _value) external;
    function transferFrom(address _from, address _to, uint256 _value) external;
    function approve(address _spender, uint256 _value) external;
}

contract EIP20Wrapper {

    function eip20Transfer(
        address token,
        address to,
        uint256 value)
        internal
        returns (bool result) {

        NonCompliantEIP20(token).transfer(to, value);

        assembly {
            switch returndatasize()   
            case 0 {                        // non compliant ERC20
                result := not(0)            // result is true
            }
            case 32 {                       // compliant ERC20
                returndatacopy(0, 0, 32) 
                result := mload(0)          // result == returndata of external call
            }
            default {                       // not an not an ERC20 token
                revert(0, 0) 
            }
        }

        require(result, "eip20Transfer failed");
    }

    function eip20TransferFrom(
        address token,
        address from,
        address to,
        uint256 value)
        internal
        returns (bool result) {

        NonCompliantEIP20(token).transferFrom(from, to, value);

        assembly {
            switch returndatasize()   
            case 0 {                        // non compliant ERC20
                result := not(0)            // result is true
            }
            case 32 {                       // compliant ERC20
                returndatacopy(0, 0, 32) 
                result := mload(0)          // result == returndata of external call
            }
            default {                       // not an not an ERC20 token
                revert(0, 0) 
            }
        }

        require(result, "eip20TransferFrom failed");
    }

    function eip20Approve(
        address token,
        address spender,
        uint256 value)
        internal
        returns (bool result) {

        NonCompliantEIP20(token).approve(spender, value);

        assembly {
            switch returndatasize()   
            case 0 {                        // non compliant ERC20
                result := not(0)            // result is true
            }
            case 32 {                       // compliant ERC20
                returndatacopy(0, 0, 32) 
                result := mload(0)          // result == returndata of external call
            }
            default {                       // not an not an ERC20 token
                revert(0, 0) 
            }
        }

        require(result, "eip20Approve failed");
    }
}

contract BZxVault is EIP20Wrapper, BZxOwnable {

    // Only the bZx contract can directly deposit ether
    function() external payable onlyBZx {}

    function withdrawEther(
        address payable to,
        uint256 value)
        public
        onlyBZx
        returns (bool)
    {
        uint256 amount = value;
        if (amount > address(this).balance) {
            amount = address(this).balance;
        }

        return (to.send(amount));
    }

    function depositToken(
        address token,
        address from,
        uint256 tokenAmount)
        public
        onlyBZx
        returns (bool)
    {
        if (tokenAmount == 0) {
            return false;
        }

        eip20TransferFrom(
            token,
            from,
            address(this),
            tokenAmount);

        return true;
    }

    function withdrawToken(
        address token,
        address to,
        uint256 tokenAmount)
        public
        onlyBZx
        returns (bool)
    {
        if (tokenAmount == 0) {
            return false;
        }

        eip20Transfer(
            token,
            to,
            tokenAmount);

        return true;
    }

    function transferTokenFrom(
        address token,
        address from,
        address to,
        uint256 tokenAmount)
        public
        onlyBZx
        returns (bool)
    {
        if (tokenAmount == 0) {
            return false;
        }

        eip20TransferFrom(
            token,
            from,
            to,
            tokenAmount);

        return true;
    }
}

// Copyright (C) 2015, 2016, 2017 Dapphub

// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

pragma solidity ^0.4.18;

contract WETH9 {
    string public name     = "Wrapped Ether";
    string public symbol   = "WETH";
    uint8  public decimals = 18;

    event  Approval(address indexed src, address indexed guy, uint wad);
    event  Transfer(address indexed src, address indexed dst, uint wad);
    event  Deposit(address indexed dst, uint wad);
    event  Withdrawal(address indexed src, uint wad);

    mapping (address => uint)                       public  balanceOf;
    mapping (address => mapping (address => uint))  public  allowance;

    function() public payable {
        deposit();
    }
    function deposit() public payable {
        balanceOf[msg.sender] += msg.value;
        Deposit(msg.sender, msg.value);
    }
    function withdraw(uint wad) public {
        require(balanceOf[msg.sender] >= wad);
        balanceOf[msg.sender] -= wad;
        msg.sender.transfer(wad);
        Withdrawal(msg.sender, wad);
    }

    function totalSupply() public view returns (uint) {
        return this.balance;
    }

    function approve(address guy, uint wad) public returns (bool) {
        allowance[msg.sender][guy] = wad;
        Approval(msg.sender, guy, wad);
        return true;
    }

    function transfer(address dst, uint wad) public returns (bool) {
        return transferFrom(msg.sender, dst, wad);
    }

    function transferFrom(address src, address dst, uint wad)
        public
        returns (bool)
    {
        require(balanceOf[src] >= wad);

        if (src != msg.sender && allowance[src][msg.sender] != uint(-1)) {
            require(allowance[src][msg.sender] >= wad);
            allowance[src][msg.sender] -= wad;
        }

        balanceOf[src] -= wad;
        balanceOf[dst] += wad;

        Transfer(src, dst, wad);

        return true;
    }
}


/*
                    GNU GENERAL PUBLIC LICENSE
                       Version 3, 29 June 2007

 Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
 Everyone is permitted to copy and distribute verbatim copies
 of this license document, but changing it is not allowed.

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  The licenses for most software and other practical works are designed
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share and change all versions of a program--to make sure it remains free
software for all its users.  We, the Free Software Foundation, use the
GNU General Public License for most of our software; it applies also to
any other work released this way by its authors.  You can apply it to
your programs, too.

  When we speak of free software, we are referring to freedom, not
price.  Our General Public Licenses are designed to make sure that you
have the freedom to distribute copies of free software (and charge for
them if you wish), that you receive source code or can get it if you
want it, that you can change the software or use pieces of it in new
free programs, and that you know you can do these things.

  To protect your rights, we need to prevent others from denying you
these rights or asking you to surrender the rights.  Therefore, you have
certain responsibilities if you distribute copies of the software, or if
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  For example, if you distribute copies of such a program, whether
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  Developers that use the GNU GPL protect your rights with two steps:
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                     END OF TERMS AND CONDITIONS

            How to Apply These Terms to Your New Programs

  If you develop a new program, and you want it to be of the greatest
possible use to the public, the best way to achieve this is to make it
free software which everyone can redistribute and change under these terms.

  To do so, attach the following notices to the program.  It is safest
to attach them to the start of each source file to most effectively
state the exclusion of warranty; and each file should have at least
the "copyright" line and a pointer to where the full notice is found.

    <one line to give the program's name and a brief idea of what it does.>
    Copyright (C) <year>  <name of author>

    This program is free software: you can redistribute it and/or modify
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    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
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Also add information on how to contact you by electronic and paper mail.

  If the program does terminal interaction, make it output a short
notice like this when it starts in an interactive mode:

    <program>  Copyright (C) <year>  <name of author>
    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
    This is free software, and you are welcome to redistribute it
    under certain conditions; type `show c' for details.

The hypothetical commands `show w' and `show c' should show the appropriate
parts of the General Public License.  Of course, your program's commands
might be different; for a GUI interface, you would use an "about box".

  You should also get your employer (if you work as a programmer) or school,
if any, to sign a "copyright disclaimer" for the program, if necessary.
For more information on this, and how to apply and follow the GNU GPL, see
<http://www.gnu.org/licenses/>.

  The GNU General Public License does not permit incorporating your program
into proprietary programs.  If your program is a subroutine library, you
may consider it more useful to permit linking proprietary applications with
the library.  If this is what you want to do, use the GNU Lesser General
Public License instead of this License.  But first, please read
<http://www.gnu.org/philosophy/why-not-lgpl.html>.

*/

/**
 * Copyright 2017-2020, bZeroX, LLC. All Rights Reserved.
 * Licensed under the Apache License, Version 2.0.
 */

pragma solidity 0.5.8;
pragma experimental ABIEncoderV2;


/**
 * @title ERC20Basic
 * @dev Simpler version of ERC20 interface
 * See https://github.com/ethereum/EIPs/issues/179
 */
contract ERC20Basic {
  function totalSupply() public view returns (uint256);
  function balanceOf(address _who) public view returns (uint256);
  function transfer(address _to, uint256 _value) public returns (bool);
  event Transfer(address indexed from, address indexed to, uint256 value);
}

/**
 * @title ERC20 interface
 * @dev see https://github.com/ethereum/EIPs/issues/20
 */
contract ERC20 is ERC20Basic {
  function allowance(address _owner, address _spender)
    public view returns (uint256);

  function transferFrom(address _from, address _to, uint256 _value)
    public returns (bool);

  function approve(address _spender, uint256 _value) public returns (bool);
  event Approval(
    address indexed owner,
    address indexed spender,
    uint256 value
  );
}

/**
 * @title EIP20/ERC20 interface
 * @dev see https://github.com/ethereum/EIPs/issues/20
 */
contract EIP20 is ERC20 {
    string public name;
    uint8 public decimals;
    string public symbol;
}

contract WETHInterface is EIP20 {
    function deposit() external payable;
    function withdraw(uint256 wad) external;
}

/**
 * @title SafeMath
 * @dev Math operations with safety checks that throw on error
 */
library SafeMath {

  /**
  * @dev Multiplies two numbers, throws on overflow.
  */
  function mul(uint256 _a, uint256 _b) internal pure returns (uint256 c) {
    // Gas optimization: this is cheaper than asserting 'a' not being zero, but the
    // benefit is lost if 'b' is also tested.
    // See: https://github.com/OpenZeppelin/openzeppelin-solidity/pull/522
    if (_a == 0) {
      return 0;
    }

    c = _a * _b;
    assert(c / _a == _b);
    return c;
  }

  /**
  * @dev Integer division of two numbers, truncating the quotient.
  */
  function div(uint256 _a, uint256 _b) internal pure returns (uint256) {
    // assert(_b > 0); // Solidity automatically throws when dividing by 0
    // uint256 c = _a / _b;
    // assert(_a == _b * c + _a % _b); // There is no case in which this doesn't hold
    return _a / _b;
  }

  /**
  * @dev Integer division of two numbers, rounding up and truncating the quotient
  */
  function divCeil(uint256 _a, uint256 _b) internal pure returns (uint256) {
    if (_a == 0) {
      return 0;
    }

    return ((_a - 1) / _b) + 1;
  }

  /**
  * @dev Subtracts two numbers, throws on overflow (i.e. if subtrahend is greater than minuend).
  */
  function sub(uint256 _a, uint256 _b) internal pure returns (uint256) {
    assert(_b <= _a);
    return _a - _b;
  }

  /**
  * @dev Adds two numbers, throws on overflow.
  */
  function add(uint256 _a, uint256 _b) internal pure returns (uint256 c) {
    c = _a + _b;
    assert(c >= _a);
    return c;
  }
}

/**
 * @title Ownable
 * @dev The Ownable contract has an owner address, and provides basic authorization control
 * functions, this simplifies the implementation of "user permissions".
 */
contract Ownable {
  address public owner;


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


  /**
   * @dev The Ownable constructor sets the original `owner` of the contract to the sender
   * account.
   */
  constructor() public {
    owner = msg.sender;
  }

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

  /**
   * @dev Allows the current owner to transfer control of the contract to a newOwner.
   * @param _newOwner The address to transfer ownership to.
   */
  function transferOwnership(address _newOwner) public onlyOwner {
    _transferOwnership(_newOwner);
  }

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

/**
 * @title Helps contracts guard against reentrancy attacks.
 * @author Remco Bloemen <remco@2π.com>, Eenae <[email protected]>
 * @dev If you mark a function `nonReentrant`, you should also
 * mark it `external`.
 */
contract ReentrancyGuard {

  /// @dev Constant for unlocked guard state - non-zero to prevent extra gas costs.
  /// See: https://github.com/OpenZeppelin/openzeppelin-solidity/issues/1056
  uint256 internal constant REENTRANCY_GUARD_FREE = 1;

  /// @dev Constant for locked guard state
  uint256 internal constant REENTRANCY_GUARD_LOCKED = 2;

  /**
   * @dev We use a single lock for the whole contract.
   */
  uint256 internal reentrancyLock = REENTRANCY_GUARD_FREE;

  /**
   * @dev Prevents a contract from calling itself, directly or indirectly.
   * If you mark a function `nonReentrant`, you should also
   * mark it `external`. Calling one `nonReentrant` function from
   * another is not supported. Instead, you can implement a
   * `private` function doing the actual work, and an `external`
   * wrapper marked as `nonReentrant`.
   */
  modifier nonReentrant() {
    require(reentrancyLock == REENTRANCY_GUARD_FREE, "nonReentrant");
    reentrancyLock = REENTRANCY_GUARD_LOCKED;
    _;
    reentrancyLock = REENTRANCY_GUARD_FREE;
  }

}

contract LoanTokenization is ReentrancyGuard, Ownable {

    uint256 internal constant MAX_UINT = 2**256 - 1;

    string public name;
    string public symbol;
    uint8 public decimals;

    address public bZxContract;
    address public bZxVault;
    address public bZxOracle;
    address public wethContract;

    address public loanTokenAddress;

    // price of token at last user checkpoint
    mapping (address => uint256) internal checkpointPrices_;
}

contract LoanTokenStorage is LoanTokenization {

    struct ListIndex {
        uint256 index;
        bool isSet;
    }

    struct LoanData {
        bytes32 loanOrderHash;
        uint256 leverageAmount;
        uint256 initialMarginAmount;
        uint256 maintenanceMarginAmount;
        uint256 maxDurationUnixTimestampSec;
        uint256 index;
        uint256 marginPremiumAmount;
        address collateralTokenAddress;
    }

    struct TokenReserves {
        address lender;
        uint256 amount;
    }

    event Borrow(
        address indexed borrower,
        uint256 borrowAmount,
        uint256 interestRate,
        address collateralTokenAddress,
        address tradeTokenToFillAddress,
        bool withdrawOnOpen
    );

    event Repay(
        bytes32 indexed loanOrderHash,
        address indexed borrower,
        address closer,
        uint256 amount,
        bool isLiquidation
    );

    event Claim(
        address indexed claimant,
        uint256 tokenAmount,
        uint256 assetAmount,
        uint256 remainingTokenAmount,
        uint256 price
    );

    bool internal isInitialized_ = false;

    address public tokenizedRegistry;

    uint256 public baseRate = 1000000000000000000; // 1.0%
    uint256 public rateMultiplier = 18750000000000000000; // 18.75%

    // slot addition (non-sequential): lowUtilBaseRate = 8000000000000000000; // 8.0%
    // slot addition (non-sequential): lowUtilRateMultiplier = 4750000000000000000; // 4.75%

    // "fee percentage retained by the oracle" = SafeMath.sub(10**20, spreadMultiplier);
    uint256 public spreadMultiplier;

    mapping (uint256 => bytes32) public loanOrderHashes; // mapping of levergeAmount to loanOrderHash
    mapping (bytes32 => LoanData) public loanOrderData; // mapping of loanOrderHash to LoanOrder
    uint256[] public leverageList;

    TokenReserves[] public burntTokenReserveList; // array of TokenReserves
    mapping (address => ListIndex) public burntTokenReserveListIndex; // mapping of lender address to ListIndex objects
    uint256 public burntTokenReserved; // total outstanding burnt token amount
    address internal nextOwedLender_;

    uint256 public totalAssetBorrow; // current amount of loan token amount tied up in loans

    uint256 public checkpointSupply;

    uint256 internal lastSettleTime_;

    uint256 public initialPrice;
}

contract AdvancedTokenStorage is LoanTokenStorage {
    using SafeMath for uint256;

    event Transfer(
        address indexed from,
        address indexed to,
        uint256 value
    );
    event Approval(
        address indexed owner,
        address indexed spender,
        uint256 value
    );
    event Mint(
        address indexed minter,
        uint256 tokenAmount,
        uint256 assetAmount,
        uint256 price
    );
    event Burn(
        address indexed burner,
        uint256 tokenAmount,
        uint256 assetAmount,
        uint256 price
    );

    mapping(address => uint256) internal balances;
    mapping (address => mapping (address => uint256)) internal allowed;
    uint256 internal totalSupply_;

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

    function balanceOf(
        address _owner)
        public
        view
        returns (uint256)
    {
        return balances[_owner];
    }

    function allowance(
        address _owner,
        address _spender)
        public
        view
        returns (uint256)
    {
        return allowed[_owner][_spender];
    }
}

contract AdvancedToken is AdvancedTokenStorage {
    using SafeMath for uint256;

    function approve(
        address _spender,
        uint256 _value)
        public
        returns (bool)
    {
        allowed[msg.sender][_spender] = _value;
        emit Approval(msg.sender, _spender, _value);
        return true;
    }

    function _mint(
        address _to,
        uint256 _tokenAmount,
        uint256 _assetAmount,
        uint256 _price)
        internal
    {
        require(_to != address(0), "15");
        totalSupply_ = totalSupply_.add(_tokenAmount);
        balances[_to] = balances[_to].add(_tokenAmount);

        emit Mint(_to, _tokenAmount, _assetAmount, _price);
        emit Transfer(address(0), _to, _tokenAmount);
    }

    function _burn(
        address _who,
        uint256 _tokenAmount,
        uint256 _assetAmount,
        uint256 _price)
        internal
    {
        require(_tokenAmount <= balances[_who], "16");
        // no need to require value <= totalSupply, since that would imply the
        // sender's balance is greater than the totalSupply, which *should* be an assertion failure

        balances[_who] = balances[_who].sub(_tokenAmount);
        if (balances[_who] <= 10) { // we can't leave such small balance quantities
            _tokenAmount = _tokenAmount.add(balances[_who]);
            balances[_who] = 0;
        }

        totalSupply_ = totalSupply_.sub(_tokenAmount);

        emit Burn(_who, _tokenAmount, _assetAmount, _price);
        emit Transfer(_who, address(0), _tokenAmount);
    }
}

contract BZxObjects {

    struct LoanOrder {
        address loanTokenAddress;
        address interestTokenAddress;
        address collateralTokenAddress;
        address oracleAddress;
        uint256 loanTokenAmount;
        uint256 interestAmount;
        uint256 initialMarginAmount;
        uint256 maintenanceMarginAmount;
        uint256 maxDurationUnixTimestampSec;
        bytes32 loanOrderHash;
    }

    struct LoanPosition {
        address trader;
        address collateralTokenAddressFilled;
        address positionTokenAddressFilled;
        uint256 loanTokenAmountFilled;
        uint256 loanTokenAmountUsed;
        uint256 collateralTokenAmountFilled;
        uint256 positionTokenAmountFilled;
        uint256 loanStartUnixTimestampSec;
        uint256 loanEndUnixTimestampSec;
        bool active;
        uint256 positionId;
    }
}

contract OracleNotifierInterface {

    function closeLoanNotifier(
        BZxObjects.LoanOrder memory loanOrder,
        BZxObjects.LoanPosition memory loanPosition,
        address loanCloser,
        uint256 closeAmount,
        bool isLiquidation)
        public
        returns (bool);
}

interface IBZx {
    function takeOrderFromiToken(
        bytes32 loanOrderHash, // existing loan order hash
        address[4] calldata sentAddresses,
            // trader: borrower/trader
            // collateralTokenAddress: collateral token
            // tradeTokenAddress: trade token
            // receiver: receiver of funds (address(0) assumes trader address)
        uint256[7] calldata sentAmounts,
            // newInterestRate: new loan interest rate
            // newLoanAmount: new loan size (principal from lender)
            // interestInitialAmount: interestAmount sent to determine initial loan length (this is included in one of the below)
            // loanTokenSent: loanTokenAmount + interestAmount + any extra
            // collateralTokenSent: collateralAmountRequired + any extra
            // tradeTokenSent: tradeTokenAmount (optional)
            // withdrawalAmount: Actual amount sent to borrower (can't exceed newLoanAmount)
        bytes calldata loanDataBytes)
        external
        payable
        returns (uint256);

    function payInterestForOracle(
        address oracleAddress,
        address interestTokenAddress)
        external
        returns (uint256);

    function getLenderInterestForOracle(
        address lender,
        address oracleAddress,
        address interestTokenAddress)
        external
        view
        returns (
            uint256 interestPaid,
            uint256 interestPaidDate,
            uint256 interestOwedPerDay,
            uint256 interestUnPaid);

    function oracleAddresses(
        address oracleAddress)
        external
        view
        returns (address);

    function getRequiredCollateral(
        address loanTokenAddress,
        address collateralTokenAddress,
        address oracleAddress,
        uint256 newLoanAmount,
        uint256 marginAmount)
        external
        view
        returns (uint256 collateralTokenAmount);

    function getBorrowAmount(
        address loanTokenAddress,
        address collateralTokenAddress,
        address oracleAddress,
        uint256 collateralTokenAmount,
        uint256 marginAmount)
        external
        view
        returns (uint256 borrowAmount);
}

interface IBZxOracle {
    function getTradeData(
        address sourceTokenAddress,
        address destTokenAddress,
        uint256 sourceTokenAmount)
        external
        view
        returns (
            uint256 sourceToDestRate,
            uint256 sourceToDestPrecision,
            uint256 destTokenAmount
        );
}

interface IWethHelper {
    function claimEther(
        address receiver,
        uint256 amount)
        external
        returns (uint256 claimAmount);
}

contract LoanTokenLogicV4 is AdvancedToken, OracleNotifierInterface {
    using SafeMath for uint256;

    address internal target_;

    //address internal constant arbitraryCaller = 0x000F400e6818158D541C3EBE45FE3AA0d47372FF;

    modifier onlyOracle() {
        require(msg.sender == IBZx(bZxContract).oracleAddresses(bZxOracle), "1");
        _;
    }


    function()
        external
    {}


    /* Public functions */

    function mintWithEther(
        address receiver)
        external
        payable
        nonReentrant
        returns (uint256 mintAmount)
    {
        require(loanTokenAddress == wethContract, "2");
        return _mintToken(
            receiver,
            msg.value
        );
    }

    function mint(
        address receiver,
        uint256 depositAmount)
        external
        nonReentrant
        returns (uint256 mintAmount)
    {
        return _mintToken(
            receiver,
            depositAmount
        );
    }

    function burnToEther(
        address receiver,
        uint256 burnAmount)
        external
        nonReentrant
        returns (uint256 loanAmountPaid)
    {
        require(loanTokenAddress == wethContract, "3");
        loanAmountPaid = _burnToken(
            burnAmount
        );

        if (loanAmountPaid != 0) {
            IWethHelper wethHelper = IWethHelper(0x3b5bDCCDFA2a0a1911984F203C19628EeB6036e0);

            _transfer(loanTokenAddress, address(wethHelper), loanAmountPaid, "4");
            require(loanAmountPaid == wethHelper.claimEther(receiver, loanAmountPaid), "4");
        }
    }

    function burn(
        address receiver,
        uint256 burnAmount)
        external
        nonReentrant
        returns (uint256 loanAmountPaid)
    {
        loanAmountPaid = _burnToken(
            burnAmount
        );

        if (loanAmountPaid != 0) {
            _transfer(loanTokenAddress, receiver, loanAmountPaid, "5");
        }
    }

    function borrowTokenFromDeposit(
        uint256 borrowAmount,
        uint256 leverageAmount,
        uint256 initialLoanDuration,    // duration in seconds
        uint256 collateralTokenSent,    // set to 0 if sending ETH
        address borrower,
        address receiver,
        address collateralTokenAddress, // address(0) means ETH and ETH must be sent with the call
        bytes memory /*loanDataBytes*/) // arbitrary order data
        public
        onlyOwner
        payable
        returns (bytes32 loanOrderHash)
    {
        require(
            ((msg.value == 0 && collateralTokenAddress != address(0) && collateralTokenSent != 0) ||
            (msg.value != 0 && (collateralTokenAddress == address(0) || collateralTokenAddress == wethContract) && collateralTokenSent == 0)),
            "6"
        );

        if (msg.value != 0) {
            collateralTokenAddress = wethContract;
            collateralTokenSent = msg.value;
        }

        uint256 _borrowAmount = borrowAmount;

        leverageAmount = uint256(keccak256(abi.encodePacked(leverageAmount,collateralTokenAddress)));
        loanOrderHash = loanOrderHashes[leverageAmount];
        require(loanOrderHash != 0, "7");

        _settleInterest();

        uint256[7] memory sentAmounts;

        LoanData memory loanOrder = loanOrderData[loanOrderHash];
        bool useFixedInterestModel = loanOrder.maxDurationUnixTimestampSec == 0;

        if (_borrowAmount == 0) {
            _borrowAmount = _getBorrowAmountForDeposit(
                collateralTokenSent,
                leverageAmount,
                initialLoanDuration,
                collateralTokenAddress
            );
            require(_borrowAmount != 0, "35");

            // withdrawalAmount
            sentAmounts[6] = _borrowAmount;
        } else {
            // withdrawalAmount
            sentAmounts[6] = _borrowAmount;
        }

        // interestRate, interestInitialAmount, borrowAmount (newBorrowAmount)
        (sentAmounts[0], sentAmounts[2], _borrowAmount) = _getInterestRateAndAmount(
            _borrowAmount,
            _totalAssetSupply(0), // interest is settled above
            initialLoanDuration,
            useFixedInterestModel
        );

        sentAmounts[6] = _borrowTokenAndUseFinal(
            loanOrderHash,
            [
                borrower,
                collateralTokenAddress,
                address(0), // tradeTokenAddress
                receiver
            ],
            [
                sentAmounts[0],         // interestRate
                _borrowAmount,
                sentAmounts[2],         // interestInitialAmount
                0,                      // loanTokenSent
                collateralTokenSent,
                0,                      // tradeTokenSent
                sentAmounts[6]          // withdrawalAmount
            ],
            ""                          // loanDataBytes
        );
        require(sentAmounts[6] == _borrowAmount, "8");
    }

    // Called to borrow and immediately get into a positions
    // assumption: depositAmount is collateral + interest deposit and will be denominated in deposit token
    // assumption: loan token and interest token are the same
    // returns loanOrderHash for the base protocol loan
    function marginTradeFromDeposit(
        uint256 depositAmount,
        uint256 leverageAmount,
        uint256 loanTokenSent,
        uint256 collateralTokenSent,
        uint256 tradeTokenSent,
        address trader,
        address depositTokenAddress,
        address collateralTokenAddress,
        address tradeTokenAddress,
        bytes memory loanDataBytes)
        public
        onlyOwner
        payable
        returns (bytes32 loanOrderHash)
    {
        require(tradeTokenAddress != address(0) &&
            tradeTokenAddress != loanTokenAddress,
            "10"
        );

        uint256 amount = depositAmount;
        // To calculate borrow amount and interest owed to lender we need deposit amount to be represented as loan token
        if (depositTokenAddress == tradeTokenAddress) {
            (,,amount) = IBZxOracle(bZxOracle).getTradeData(
                tradeTokenAddress,
                loanTokenAddress,
                amount
            );
        } else if (depositTokenAddress != loanTokenAddress) {
            // depositTokenAddress can only be tradeTokenAddress or loanTokenAddress
            revert("11");
        }

        loanOrderHash = _borrowTokenAndUse(
            leverageAmount,
            [
                trader,
                collateralTokenAddress,     // collateralTokenAddress
                tradeTokenAddress,          // tradeTokenAddress
                trader                      // receiver
            ],
            [
                0,                      // interestRate (found later)
                amount,                 // amount of deposit
                0,                      // interestInitialAmount (interest is calculated based on fixed-term loan)
                loanTokenSent,
                collateralTokenSent,
                tradeTokenSent,
                0
            ],
            true,                       // amountIsADeposit
            loanDataBytes
        );
    }

    function transfer(
        address _to,
        uint256 _value)
        public
        returns (bool)
    {
        require(_value <= balances[msg.sender] &&
            _to != address(0),
            "13"
        );

        balances[msg.sender] = balances[msg.sender].sub(_value);
        balances[_to] = balances[_to].add(_value);

        // handle checkpoint update
        uint256 currentPrice = tokenPrice();
        if (balances[msg.sender] != 0) {
            checkpointPrices_[msg.sender] = currentPrice;
        } else {
            checkpointPrices_[msg.sender] = 0;
        }
        if (balances[_to] != 0) {
            checkpointPrices_[_to] = currentPrice;
        } else {
            checkpointPrices_[_to] = 0;
        }

        emit Transfer(msg.sender, _to, _value);
        return true;
    }

    function transferFrom(
        address _from,
        address _to,
        uint256 _value)
        public
        returns (bool)
    {
        uint256 allowanceAmount = allowed[_from][msg.sender];
        require(_value <= balances[_from] &&
            _value <= allowanceAmount &&
            _to != address(0),
            "14"
        );

        balances[_from] = balances[_from].sub(_value);
        balances[_to] = balances[_to].add(_value);
        if (allowanceAmount < MAX_UINT) {
            allowed[_from][msg.sender] = allowanceAmount.sub(_value);
        }

        // handle checkpoint update
        uint256 currentPrice = tokenPrice();
        if (balances[_from] != 0) {
            checkpointPrices_[_from] = currentPrice;
        } else {
            checkpointPrices_[_from] = 0;
        }
        if (balances[_to] != 0) {
            checkpointPrices_[_to] = currentPrice;
        } else {
            checkpointPrices_[_to] = 0;
        }

        emit Transfer(_from, _to, _value);
        return true;
    }


    /* Public View functions */

    function tokenPrice()
        public
        view
        returns (uint256 price)
    {
        uint256 interestUnPaid;
        if (lastSettleTime_ != block.timestamp) {
            (,interestUnPaid) = _getAllInterest();
        }

        return _tokenPrice(_totalAssetSupply(interestUnPaid));
    }

    function checkpointPrice(
        address _user)
        public
        view
        returns (uint256 price)
    {
        return checkpointPrices_[_user];
    }

    function marketLiquidity()
        public
        view
        returns (uint256)
    {
        uint256 totalSupply = totalAssetSupply();
        if (totalSupply > totalAssetBorrow) {
            return totalSupply.sub(totalAssetBorrow);
        }
    }

    function protocolInterestRate()
        public
        view
        returns (uint256)
    {
        return _protocolInterestRate(totalAssetBorrow);
    }

    // the minimum rate the next base protocol borrower will receive for variable-rate loans
    function borrowInterestRate()
        public
        view
        returns (uint256)
    {
        return _nextBorrowInterestRate(
            0,              // borrowAmount
            false           // useFixedInterestModel
        );
    }

    function nextBorrowInterestRate(
        uint256 borrowAmount)
        public
        view
        returns (uint256)
    {
        return _nextBorrowInterestRate(
            borrowAmount,
            false           // useFixedInterestModel
        );
    }

    function nextBorrowInterestRateWithOption(
        uint256 borrowAmount,
        bool useFixedInterestModel)
        public
        view
        returns (uint256)
    {
        return _nextBorrowInterestRate(
            borrowAmount,
            useFixedInterestModel
        );
    }

    // the average interest that borrowers are currently paying for open loans
    function avgBorrowInterestRate()
        public
        view
        returns (uint256)
    {
        uint256 assetBorrow = totalAssetBorrow;
        if (assetBorrow != 0) {
            return _protocolInterestRate(assetBorrow)
                .mul(checkpointSupply)
                .div(totalAssetSupply());
        } else {
            return _getLowUtilBaseRate();
        }
    }

    // interest that lenders are currently receiving when supplying to the pool
    function supplyInterestRate()
        public
        view
        returns (uint256)
    {
        return totalSupplyInterestRate(totalAssetSupply());
    }

    function nextSupplyInterestRate(
        uint256 supplyAmount)
        public
        view
        returns (uint256)
    {
        return totalSupplyInterestRate(totalAssetSupply().add(supplyAmount));
    }

    function totalSupplyInterestRate(
        uint256 assetSupply)
        public
        view
        returns (uint256)
    {
        uint256 assetBorrow = totalAssetBorrow;
        if (assetBorrow != 0) {
            return _supplyInterestRate(
                assetBorrow,
                assetSupply
            );
        }
    }

    function totalAssetSupply()
        public
        view
        returns (uint256)
    {
        uint256 interestUnPaid;
        if (lastSettleTime_ != block.timestamp) {
            (,interestUnPaid) = _getAllInterest();
        }

        return _totalAssetSupply(interestUnPaid);
    }

    function getMaxEscrowAmount(
        uint256 leverageAmount)
        public
        view
        returns (uint256)
    {
        LoanData memory loanData = loanOrderData[loanOrderHashes[leverageAmount]];
        if (loanData.initialMarginAmount == 0)
            return 0;

        return marketLiquidity()
            .mul(loanData.initialMarginAmount)
            .div(_adjustValue(
                10**20, // maximum possible interest (100%)
                loanData.maxDurationUnixTimestampSec,
                loanData.initialMarginAmount));
    }

    function getLeverageList()
        public
        view
        returns (uint256[] memory)
    {
        return leverageList;
    }

    function getLoanData(
        bytes32 loanOrderHash)
        public
        view
        returns (LoanData memory)
    {
        return loanOrderData[loanOrderHash];
    }

    // returns the user's balance of underlying token
    function assetBalanceOf(
        address _owner)
        public
        view
        returns (uint256)
    {
        return balanceOf(_owner)
            .mul(tokenPrice())
            .div(10**18);
    }

    function getDepositAmountForBorrow(
        uint256 borrowAmount,
        uint256 leverageAmount,             // use 2000000000000000000 for 150% initial margin
        uint256 initialLoanDuration,        // duration in seconds
        address collateralTokenAddress)     // address(0) means ETH
        public
        view
        returns (uint256 depositAmount)
    {
        if (borrowAmount != 0) {
            leverageAmount = uint256(keccak256(abi.encodePacked(leverageAmount,collateralTokenAddress)));
            LoanData memory loanOrder = loanOrderData[loanOrderHashes[leverageAmount]];
            uint256 marginAmount = loanOrder.initialMarginAmount
                .add(10**20); // adjust for over-collateralized loan
                //.add(loanOrder.marginPremiumAmount);

            // adjust value since interest is also borrowed
            borrowAmount = borrowAmount
                .mul(_getTargetNextRateMultiplierValue(initialLoanDuration))
                .div(10**22);

            if (borrowAmount <= ERC20(loanTokenAddress).balanceOf(address(this))) {
                return IBZx(bZxContract).getRequiredCollateral(
                    loanTokenAddress,
                    collateralTokenAddress != address(0) ? collateralTokenAddress : wethContract,
                    bZxOracle,
                    borrowAmount,
                    marginAmount
                ).add(10); // add some dust to ensure enough is borrowed later
            }
        }
    }

    function getBorrowAmountForDeposit(
        uint256 depositAmount,
        uint256 leverageAmount,             // use 2000000000000000000 for 150% initial margin
        uint256 initialLoanDuration,        // duration in seconds
        address collateralTokenAddress)     // address(0) means ETH
        public
        view
        returns (uint256 borrowAmount)
    {
        leverageAmount = uint256(keccak256(abi.encodePacked(leverageAmount,collateralTokenAddress)));
        borrowAmount = _getBorrowAmountForDeposit(
            depositAmount,
            leverageAmount,
            initialLoanDuration,
            collateralTokenAddress
        );
    }


    /* Internal functions */

    function _mintToken(
        address receiver,
        uint256 depositAmount)
        internal
        returns (uint256 mintAmount)
    {
        require (depositAmount != 0, "17");

        _settleInterest();

        uint256 currentPrice = _tokenPrice(_totalAssetSupply(0));
        mintAmount = depositAmount.mul(10**18).div(currentPrice);

        if (msg.value == 0) {
            _transferFrom(loanTokenAddress, msg.sender, address(this), depositAmount, "18");
        } else {
            WETHInterface(wethContract).deposit.value(depositAmount)();
        }

        _mint(receiver, mintAmount, depositAmount, currentPrice);

        checkpointPrices_[receiver] = currentPrice;
    }

    function _burnToken(
        uint256 burnAmount)
        internal
        returns (uint256 loanAmountPaid)
    {
        require(burnAmount != 0, "19");

        if (burnAmount > balanceOf(msg.sender)) {
            burnAmount = balanceOf(msg.sender);
        }

        _settleInterest();

        uint256 currentPrice = _tokenPrice(_totalAssetSupply(0));

        uint256 loanAmountOwed = burnAmount.mul(currentPrice).div(10**18);
        uint256 loanAmountAvailableInContract = ERC20(loanTokenAddress).balanceOf(address(this));

        loanAmountPaid = loanAmountOwed;
        require(loanAmountPaid <= loanAmountAvailableInContract, "37");

        _burn(msg.sender, burnAmount, loanAmountPaid, currentPrice);

        if (balances[msg.sender] != 0) {
            checkpointPrices_[msg.sender] = currentPrice;
        } else {
            checkpointPrices_[msg.sender] = 0;
        }
    }

    function _settleInterest()
        internal
    {
        if (lastSettleTime_ != block.timestamp) {
            IBZx(bZxContract).payInterestForOracle(
                bZxOracle, // (leave as original value)
                loanTokenAddress // same as interestTokenAddress
            );

            lastSettleTime_ = block.timestamp;
        }
    }

    function _getBorrowAmountForDeposit(
        uint256 depositAmount,
        uint256 leverageAmount,             // use 2000000000000000000 for 150% initial margin
        uint256 initialLoanDuration,        // duration in seconds
        address collateralTokenAddress)     // address(0) means ETH
        internal
        view
        returns (uint256 borrowAmount)
    {
        if (depositAmount != 0) {
            LoanData memory loanOrder = loanOrderData[loanOrderHashes[leverageAmount]];
            uint256 marginAmount = loanOrder.initialMarginAmount
                .add(10**20); // adjust for over-collateralized loan
                //.add(loanOrder.marginPremiumAmount);

            borrowAmount = IBZx(bZxContract).getBorrowAmount(
                loanTokenAddress,
                collateralTokenAddress != address(0) ? collateralTokenAddress : wethContract,
                bZxOracle,
                depositAmount,
                marginAmount
            );

            // adjust value since interest is also borrowed
            borrowAmount = borrowAmount
                .mul(10**22)
                .div(_getTargetNextRateMultiplierValue(initialLoanDuration));

            if (borrowAmount > ERC20(loanTokenAddress).balanceOf(address(this))) {
                borrowAmount = 0;
            }
        }
    }

    function _getTargetNextRateMultiplierValue(
        uint256 initialLoanDuration)
        internal
        view
        returns (uint256)
    {
        return rateMultiplier
            .mul(80 ether)
            .div(10**20)
            .add(baseRate)
            .mul(initialLoanDuration)
            .div(315360) // 365 * 86400 / 100
            .add(10**22);
    }

    function _getInterestRateAndAmount(
        uint256 borrowAmount,
        uint256 assetSupply,
        uint256 initialLoanDuration,        // duration in seconds
        bool useFixedInterestModel)         // False=variable interest, True=fixed interest
        internal
        view
        returns (uint256 interestRate, uint256 interestInitialAmount, uint256 newBorrowAmount)
    {
        (,interestInitialAmount) = _getInterestRateAndAmount2(
            borrowAmount,
            assetSupply,
            initialLoanDuration,
            useFixedInterestModel
        );

        (interestRate, interestInitialAmount) = _getInterestRateAndAmount2(
            borrowAmount
                .add(interestInitialAmount),
            assetSupply,
            initialLoanDuration,
            useFixedInterestModel
        );

        newBorrowAmount = borrowAmount
            .add(interestInitialAmount);
    }

    function _getInterestRateAndAmount2(
        uint256 borrowAmount,
        uint256 assetSupply,
        uint256 initialLoanDuration,
        bool useFixedInterestModel)
        internal
        view
        returns (uint256 interestRate, uint256 interestInitialAmount)
    {
        interestRate = _nextBorrowInterestRate2(
            borrowAmount,
            assetSupply,
            useFixedInterestModel
        );

        // initial interestInitialAmount
        interestInitialAmount = borrowAmount
            .mul(interestRate)
            .mul(initialLoanDuration)
            .div(31536000 * 10**20); // 365 * 86400 * 10**20
    }

    function _borrowTokenAndUse(
        uint256 leverageAmount,
        address[4] memory sentAddresses,
        uint256[7] memory sentAmounts,
        bool amountIsADeposit,
        bytes memory loanDataBytes)
        internal
        returns (bytes32 loanOrderHash)
    {
        require(sentAmounts[1] != 0, "21"); // amount

        loanOrderHash = loanOrderHashes[leverageAmount];
        require(loanOrderHash != 0, "22");

        _settleInterest();

        LoanData memory loanOrder = loanOrderData[loanOrderHash];
        bool useFixedInterestModel = loanOrder.maxDurationUnixTimestampSec == 0;
        //sentAmounts[7] = loanOrder.marginPremiumAmount;

        if (amountIsADeposit) {
            (sentAmounts[1], sentAmounts[0]) = _getBorrowAmountAndRate( // borrowAmount, interestRate
                loanOrderHash,
                sentAmounts[1], // amount
                useFixedInterestModel
            );

            // update for borrowAmount
            sentAmounts[6] = sentAmounts[1]; // borrowAmount
        } else {
            // amount is borrow amount
            sentAmounts[0] = _nextBorrowInterestRate2( // interestRate
                sentAmounts[1], // amount
                _totalAssetSupply(0),
                useFixedInterestModel
            );
        }

        if (sentAddresses[2] == address(0)) { // tradeTokenAddress
            // tradeTokenSent is ignored if trade token isn't specified
            sentAmounts[5] = 0;
        }

        uint256 borrowAmount = _borrowTokenAndUseFinal(
            loanOrderHash,
            sentAddresses,
            sentAmounts,
            loanDataBytes
        );
        require(borrowAmount == sentAmounts[1], "23");
    }

    // returns borrowAmount
    function _borrowTokenAndUseFinal(
        bytes32 loanOrderHash,
        address[4] memory sentAddresses,
        uint256[7] memory sentAmounts,
        bytes memory loanDataBytes)
        internal
        returns (uint256)
    {
        _checkPause();

        require (sentAmounts[1] <= ERC20(loanTokenAddress).balanceOf(address(this)) && // borrowAmount
            sentAddresses[0] != address(0), // borrower
            "24"
        );

	    if (sentAddresses[3] == address(0)) {
            sentAddresses[3] = sentAddresses[0]; // receiver = borrower
        }

        // handle transfers prior to adding borrowAmount to loanTokenSent
        _verifyTransfers(
            sentAddresses,
            sentAmounts
        );

        // adding the loan token amount from the lender to loanTokenSent
        sentAmounts[3] = sentAmounts[3]
            .add(sentAmounts[1]); // borrowAmount

        uint256 msgValue;
        if (msg.value != 0) {
            msgValue = address(this).balance;
            if (msgValue > msg.value) {
                msgValue = msg.value;
            }
        }
        sentAmounts[1] = IBZx(bZxContract).takeOrderFromiToken.value(msgValue)( // borrowAmount
            loanOrderHash,
            sentAddresses,
            sentAmounts,
            loanDataBytes
        );
        require (sentAmounts[1] != 0, "25");

        // update total borrowed amount outstanding in loans
        totalAssetBorrow = totalAssetBorrow
            .add(sentAmounts[1]); // borrowAmount

        // checkpoint supply since the base protocol borrow stats have changed
        checkpointSupply = _totalAssetSupply(0);

        emit Borrow(
            sentAddresses[0],               // borrower
            sentAmounts[1],                 // borrowAmount
            sentAmounts[0],                 // interestRate
            sentAddresses[1],               // collateralTokenAddress
            sentAddresses[2],               // tradeTokenAddress
            sentAddresses[2] == address(0)  // withdrawOnOpen
        );

        return sentAmounts[1]; // borrowAmount;
    }

    // sentAddresses[0]: borrower
    // sentAddresses[1]: collateralTokenAddress
    // sentAddresses[2]: tradeTokenAddress
    // sentAddresses[3]: receiver
    // sentAmounts[0]: interestRate
    // sentAmounts[1]: borrowAmount
    // sentAmounts[2]: interestInitialAmount
    // sentAmounts[3]: loanTokenSent
    // sentAmounts[4]: collateralTokenSent
    // sentAmounts[5]: tradeTokenSent
    // sentAmounts[6]: withdrawalAmount
    function _verifyTransfers(
        address[4] memory sentAddresses,
        uint256[7] memory sentAmounts)
        internal
    {
        address collateralTokenAddress = sentAddresses[1];
        address tradeTokenAddress = sentAddresses[2];
        address receiver = sentAddresses[3];
        uint256 borrowAmount = sentAmounts[1];
        uint256 loanTokenSent = sentAmounts[3];
        uint256 collateralTokenSent = sentAmounts[4];
        uint256 tradeTokenSent = sentAmounts[5];
        uint256 withdrawalAmount = sentAmounts[6];

        bool success;
        if (tradeTokenAddress == address(0)) { // withdrawOnOpen == true
            if (loanTokenAddress == wethContract) {
                IWethHelper wethHelper = IWethHelper(0x3b5bDCCDFA2a0a1911984F203C19628EeB6036e0);

                _transfer(loanTokenAddress, address(wethHelper), withdrawalAmount, "");
                success = withdrawalAmount == wethHelper.claimEther(receiver, withdrawalAmount);
            } else {
                _transfer(loanTokenAddress, receiver, withdrawalAmount, "");
                success = true;
            }

            if (success && borrowAmount > withdrawalAmount) {
                _transfer(loanTokenAddress, bZxVault, borrowAmount - withdrawalAmount, "");
            }
            require(success, "26");
        } else {
            _transfer(loanTokenAddress, bZxVault, borrowAmount, "26");
        }

        if (collateralTokenSent != 0) {
            if (collateralTokenAddress == wethContract && msg.value != 0 && collateralTokenSent == msg.value) {
                WETHInterface(wethContract).deposit.value(collateralTokenSent)();
                _transfer(collateralTokenAddress, bZxVault, collateralTokenSent, "27");
            } else {
                if (collateralTokenAddress == loanTokenAddress) {
                    loanTokenSent = loanTokenSent.add(collateralTokenSent);
                } else if (collateralTokenAddress == tradeTokenAddress) {
                    tradeTokenSent = tradeTokenSent.add(collateralTokenSent);
                } else {
                    _transferFrom(collateralTokenAddress, msg.sender, bZxVault, collateralTokenSent, "27");
                }
            }
        }

        if (loanTokenSent != 0) {
            if (loanTokenAddress == tradeTokenAddress) {
                tradeTokenSent = tradeTokenSent.add(loanTokenSent);
            } else {
                _transferFrom(loanTokenAddress, msg.sender, bZxVault, loanTokenSent, "31");
            }
        }

        if (tradeTokenSent != 0) {
            _transferFrom(tradeTokenAddress, msg.sender, bZxVault, tradeTokenSent, "32");
        }
    }

    function _transfer(
        address token,
        address to,
        uint256 amount,
        string memory errorMsg)
        internal
    {
        (bool success,) = token.call(
            abi.encodeWithSelector(
                0xa9059cbb, // transfer(address,uint256)
                to,
                amount
            )
        );
        require(success, errorMsg);
    }

    function _transferFrom(
        address token,
        address from,
        address to,
        uint256 amount,
        string memory errorMsg)
        internal
    {
        (bool success,) = token.call(
            abi.encodeWithSelector(
                0x23b872dd, // transferFrom(address,address,uint256)
                from,
                to,
                amount
            )
        );
        require(success, errorMsg);
    }

    /* Internal View functions */

    function _tokenPrice(
        uint256 assetSupply)
        internal
        view
        returns (uint256)
    {
        uint256 totalTokenSupply = totalSupply_;

        return totalTokenSupply != 0 ?
            assetSupply
                .mul(10**18)
                .div(totalTokenSupply) : initialPrice;
    }

    function _protocolInterestRate(
        uint256 assetBorrow)
        internal
        view
        returns (uint256)
    {
        if (assetBorrow != 0) {
            (uint256 interestOwedPerDay,) = _getAllInterest();
            return interestOwedPerDay
                .mul(10**20)
                .div(assetBorrow)
                .mul(365);
        }
    }

    // next supply interest adjustment
    function _supplyInterestRate(
        uint256 assetBorrow,
        uint256 assetSupply)
        public
        view
        returns (uint256)
    {
        if (assetBorrow != 0 && assetSupply >= assetBorrow) {
            return _protocolInterestRate(assetBorrow)
                .mul(_utilizationRate(assetBorrow, assetSupply))
                .mul(spreadMultiplier)
                .div(10**40);
        }
    }

    function _nextBorrowInterestRate(
        uint256 borrowAmount,
        bool useFixedInterestModel)
        internal
        view
        returns (uint256)
    {
        uint256 interestUnPaid;
        if (borrowAmount != 0) {
            if (lastSettleTime_ != block.timestamp) {
                (,interestUnPaid) = _getAllInterest();
            }

            uint256 balance = ERC20(loanTokenAddress).balanceOf(address(this))
                .add(interestUnPaid);
            if (borrowAmount > balance) {
                borrowAmount = balance;
            }
        }

        return _nextBorrowInterestRate2(
            borrowAmount,
            _totalAssetSupply(interestUnPaid),
            useFixedInterestModel
        );
    }

    function _nextBorrowInterestRate2(
        uint256 newBorrowAmount,
        uint256 assetSupply,
        bool useFixedInterestModel)
        internal
        view
        returns (uint256 nextRate)
    {
        uint256 utilRate = _utilizationRate(
            totalAssetBorrow.add(newBorrowAmount),
            assetSupply
        );

        uint256 minRate;
        uint256 maxRate;
        uint256 thisBaseRate;
        uint256 thisRateMultiplier;

        if (useFixedInterestModel) {
            if (utilRate < 80 ether) {
                // target 80% utilization when loan is fixed-rate and utilization is under 80%
                utilRate = 80 ether;
            }

            //keccak256("iToken_FixedInterestBaseRate")
            //keccak256("iToken_FixedInterestRateMultiplier")
            assembly {
                thisBaseRate := sload(0x185a40c6b6d3f849f72c71ea950323d21149c27a9d90f7dc5e5ea2d332edcf7f)
                thisRateMultiplier := sload(0x9ff54bc0049f5eab56ca7cd14591be3f7ed6355b856d01e3770305c74a004ea2)
            }
        } else if (utilRate < 50 ether) {
            thisBaseRate = _getLowUtilBaseRate();

            //keccak256("iToken_LowUtilRateMultiplier")
            assembly {
                thisRateMultiplier := sload(0x2b4858b1bc9e2d14afab03340ce5f6c81b703c86a0c570653ae586534e095fb1)
            }
        } else {
            thisBaseRate = baseRate;
            thisRateMultiplier = rateMultiplier;
        }

        if (utilRate > 90 ether) {
            // scale rate proportionally up to 100%

            utilRate = utilRate.sub(90 ether);
            if (utilRate > 10 ether)
                utilRate = 10 ether;

            maxRate = thisRateMultiplier
                .add(thisBaseRate)
                .mul(90)
                .div(100);

            nextRate = utilRate
                .mul(SafeMath.sub(100 ether, maxRate))
                .div(10 ether)
                .add(maxRate);
        } else {
            nextRate = utilRate
                .mul(thisRateMultiplier)
                .div(10**20)
                .add(thisBaseRate);

            minRate = thisBaseRate;
            maxRate = thisRateMultiplier
                .add(thisBaseRate);

            if (nextRate < minRate)
                nextRate = minRate;
            else if (nextRate > maxRate)
                nextRate = maxRate;
        }
    }

    function _getAllInterest()
        internal
        view
        returns (
            uint256 interestOwedPerDay,
            uint256 interestUnPaid)
    {
        (,,interestOwedPerDay,interestUnPaid) = IBZx(bZxContract).getLenderInterestForOracle(
            address(this),
            bZxOracle, // (leave as original value)
            loanTokenAddress // same as interestTokenAddress
        );

        interestUnPaid = interestUnPaid
            .mul(spreadMultiplier)
            .div(10**20);
    }

    function _getBorrowAmountAndRate(
        bytes32 loanOrderHash,
        uint256 depositAmount,
        bool useFixedInterestModel)
        internal
        view
        returns (uint256 borrowAmount, uint256 interestRate)
    {
        LoanData memory loanData = loanOrderData[loanOrderHash];
        require(loanData.initialMarginAmount != 0, "33");

        interestRate = _nextBorrowInterestRate2(
            depositAmount
                .mul(10**20)
                .div(loanData.initialMarginAmount),
            totalAssetSupply(),
            useFixedInterestModel
        );

        // assumes that loan, collateral, and interest token are the same
        borrowAmount = depositAmount
            .mul(10**40)
            .div(_adjustValue(
                interestRate,
                loanData.maxDurationUnixTimestampSec,
                loanData.initialMarginAmount))
            .div(loanData.initialMarginAmount);
    }

    function _totalAssetSupply(
        uint256 interestUnPaid)
        internal
        view
        returns (uint256 assetSupply)
    {
        if (totalSupply_ != 0) {
            uint256 assetsBalance = burntTokenReserved; // temporary holder when flash lending
            if (assetsBalance == 0) {
                assetsBalance = ERC20(loanTokenAddress).balanceOf(address(this))
                    .add(totalAssetBorrow);
            }

            return assetsBalance
                .add(interestUnPaid);
        }
    }

    function _getLowUtilBaseRate()
        internal
        view
        returns (uint256 lowUtilBaseRate)
    {
        //keccak256("iToken_LowUtilBaseRate")
        assembly {
            lowUtilBaseRate := sload(0x3d82e958c891799f357c1316ae5543412952ae5c423336f8929ed7458039c995)
        }
    }

    function _checkPause()
        internal
        view
    {
        //keccak256("iToken_FunctionPause")
        bytes32 slot = keccak256(abi.encodePacked(msg.sig, uint256(0xd46a704bc285dbd6ff5ad3863506260b1df02812f4f857c8cc852317a6ac64f2)));
        bool isPaused;
        assembly {
            isPaused := sload(slot)
        }
        require(!isPaused, "unauthorized");
    }

    function _adjustValue(
        uint256 interestRate,
        uint256 maxDuration,
        uint256 marginAmount)
        internal
        pure
        returns (uint256)
    {
        return maxDuration != 0 ?
            interestRate
                .mul(10**20)
                .div(31536000) // 86400 * 365
                .mul(maxDuration)
                .div(marginAmount)
                .add(10**20) :
            10**20;
    }

    function _utilizationRate(
        uint256 assetBorrow,
        uint256 assetSupply)
        internal
        pure
        returns (uint256)
    {
        if (assetBorrow != 0 && assetSupply != 0) {
            // U = total_borrow / total_supply
            return assetBorrow
                .mul(10**20)
                .div(assetSupply);
        }
    }


    /* Oracle-Only functions */

    // called only by BZxOracle when a loan is partially or fully closed
    function closeLoanNotifier(
        BZxObjects.LoanOrder memory loanOrder,
        BZxObjects.LoanPosition memory loanPosition,
        address loanCloser,
        uint256 closeAmount,
        bool isLiquidation)
        public
        onlyOracle
        returns (bool)
    {
        _settleInterest();

        LoanData memory loanData = loanOrderData[loanOrder.loanOrderHash];
        if (loanData.loanOrderHash == loanOrder.loanOrderHash) {
            totalAssetBorrow = totalAssetBorrow > closeAmount ?
                totalAssetBorrow.sub(closeAmount) : 0;

            emit Repay(
                loanOrder.loanOrderHash,    // loanOrderHash
                loanPosition.trader,        // borrower
                loanCloser,                 // closer
                closeAmount,                // amount
                isLiquidation               // isLiquidation
            );

            if (closeAmount == 0)
                return true;

            // checkpoint supply since the base protocol borrow stats have changed
            checkpointSupply = _totalAssetSupply(0);

            return true;
        } else {
            return false;
        }
    }


    /* Owner-Only functions */

    function updateSettings(
        address settingsTarget,
        bytes memory callData)
        public
    {
        if (msg.sender != owner) {
            address _lowerAdmin;
            address _lowerAdminContract;

            //keccak256("iToken_LowerAdminAddress")
            //keccak256("iToken_LowerAdminContract")
            assembly {
                _lowerAdmin := sload(0x7ad06df6a0af6bd602d90db766e0d5f253b45187c3717a0f9026ea8b10ff0d4b)
                _lowerAdminContract := sload(0x34b31cff1dbd8374124bd4505521fc29cab0f9554a5386ba7d784a4e611c7e31)
            }
            require(msg.sender == _lowerAdmin && settingsTarget == _lowerAdminContract);
        }

        address currentTarget = target_;
        target_ = settingsTarget;

        (bool result,) = address(this).call(callData);

        uint256 size;
        uint256 ptr;
        assembly {
            size := returndatasize
            ptr := mload(0x40)
            returndatacopy(ptr, 0, size)
            if eq(result, 0) { revert(ptr, size) }
        }

        target_ = currentTarget;

        assembly {
            return(ptr, size)
        }
    }
}

/**
 * Copyright 2017–2018, bZeroX, LLC. All Rights Reserved.
 * Licensed under the Apache License, Version 2.0.
 */
 
pragma solidity 0.5.3;


/**
 * @title Ownable
 * @dev The Ownable contract has an owner address, and provides basic authorization control
 * functions, this simplifies the implementation of "user permissions".
 */
contract Ownable {
  address public owner;

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

  /**
   * @dev The Ownable constructor sets the original `owner` of the contract to the sender
   * account.
   */
  constructor() public {
    owner = msg.sender;
  }

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

  /**
   * @dev Allows the current owner to transfer control of the contract to a newOwner.
   * @param _newOwner The address to transfer ownership to.
   */
  function transferOwnership(address _newOwner) public onlyOwner {
    _transferOwnership(_newOwner);
  }

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

/**
 * @title Helps contracts guard against reentrancy attacks.
 * @author Remco Bloemen <remco@2π.com>, Eenae <[email protected]>
 * @dev If you mark a function `nonReentrant`, you should also
 * mark it `external`.
 */
contract ReentrancyGuard {

  /// @dev Constant for unlocked guard state - non-zero to prevent extra gas costs.
  /// See: https://github.com/OpenZeppelin/openzeppelin-solidity/issues/1056
  uint256 private constant REENTRANCY_GUARD_FREE = 1;

  /// @dev Constant for locked guard state
  uint256 private constant REENTRANCY_GUARD_LOCKED = 2;

  /**
   * @dev We use a single lock for the whole contract.
   */
  uint256 private reentrancyLock = REENTRANCY_GUARD_FREE;

  /**
   * @dev Prevents a contract from calling itself, directly or indirectly.
   * If you mark a function `nonReentrant`, you should also
   * mark it `external`. Calling one `nonReentrant` function from
   * another is not supported. Instead, you can implement a
   * `private` function doing the actual work, and an `external`
   * wrapper marked as `nonReentrant`.
   */
  modifier nonReentrant() {
    require(reentrancyLock == REENTRANCY_GUARD_FREE);
    reentrancyLock = REENTRANCY_GUARD_LOCKED;
    _;
    reentrancyLock = REENTRANCY_GUARD_FREE;
  }

}

contract GasTracker {

    uint256 internal gasUsed;

    modifier tracksGas() {
        // tx call 21k gas
        gasUsed = gasleft() + 21000;

        _; // modified function body inserted here

        gasUsed = 0; // zero out the storage so we don't persist anything
    }
}

contract BZxObjects {

    struct ListIndex {
        uint256 index;
        bool isSet;
    }

    struct LoanOrder {
        address loanTokenAddress;
        address interestTokenAddress;
        address collateralTokenAddress;
        address oracleAddress;
        uint256 loanTokenAmount;
        uint256 interestAmount;
        uint256 initialMarginAmount;
        uint256 maintenanceMarginAmount;
        uint256 maxDurationUnixTimestampSec;
        bytes32 loanOrderHash;
    }

    struct LoanOrderAux {
        address makerAddress;
        address takerAddress;
        address feeRecipientAddress;
        address tradeTokenToFillAddress;
        uint256 lenderRelayFee;
        uint256 traderRelayFee;
        uint256 makerRole;
        uint256 expirationUnixTimestampSec;
        bool withdrawOnOpen;
        string description;
    }

    struct LoanPosition {
        address trader;
        address collateralTokenAddressFilled;
        address positionTokenAddressFilled;
        uint256 loanTokenAmountFilled;
        uint256 loanTokenAmountUsed;
        uint256 collateralTokenAmountFilled;
        uint256 positionTokenAmountFilled;
        uint256 loanStartUnixTimestampSec;
        uint256 loanEndUnixTimestampSec;
        bool active;
        uint256 positionId;
    }

    struct PositionRef {
        bytes32 loanOrderHash;
        uint256 positionId;
    }

    struct LenderInterest {
        uint256 interestOwedPerDay;
        uint256 interestPaid;
        uint256 interestPaidDate;
    }

    struct TraderInterest {
        uint256 interestOwedPerDay;
        uint256 interestPaid;
        uint256 interestDepositTotal;
        uint256 interestUpdatedDate;
    }
}

contract BZxEvents {

    event LogLoanAdded (
        bytes32 indexed loanOrderHash,
        address adderAddress,
        address indexed makerAddress,
        address indexed feeRecipientAddress,
        uint256 lenderRelayFee,
        uint256 traderRelayFee,
        uint256 maxDuration,
        uint256 makerRole
    );

    event LogLoanTaken (
        address indexed lender,
        address indexed trader,
        address loanTokenAddress,
        address collateralTokenAddress,
        uint256 loanTokenAmount,
        uint256 collateralTokenAmount,
        uint256 loanEndUnixTimestampSec,
        bool firstFill,
        bytes32 indexed loanOrderHash,
        uint256 positionId
    );

    event LogLoanCancelled(
        address indexed makerAddress,
        uint256 cancelLoanTokenAmount,
        uint256 remainingLoanTokenAmount,
        bytes32 indexed loanOrderHash
    );

    event LogLoanClosed(
        address indexed lender,
        address indexed trader,
        address loanCloser,
        bool isLiquidation,
        bytes32 indexed loanOrderHash,
        uint256 positionId
    );

    event LogPositionTraded(
        bytes32 indexed loanOrderHash,
        address indexed trader,
        address sourceTokenAddress,
        address destTokenAddress,
        uint256 sourceTokenAmount,
        uint256 destTokenAmount,
        uint256 positionId
    );

    event LogWithdrawPosition(
        bytes32 indexed loanOrderHash,
        address indexed trader,
        uint256 positionAmount,
        uint256 remainingPosition,
        uint256 positionId
    );

    event LogPayInterestForOracle(
        address indexed lender,
        address indexed oracleAddress,
        address indexed interestTokenAddress,
        uint256 amountPaid,
        uint256 totalAccrued
    );

    event LogPayInterestForOrder(
        bytes32 indexed loanOrderHash,
        address indexed lender,
        address indexed interestTokenAddress,
        uint256 amountPaid,
        uint256 totalAccrued,
        uint256 loanCount
    );

    event LogChangeTraderOwnership(
        bytes32 indexed loanOrderHash,
        address indexed oldOwner,
        address indexed newOwner
    );

    event LogChangeLenderOwnership(
        bytes32 indexed loanOrderHash,
        address indexed oldOwner,
        address indexed newOwner
    );

    event LogUpdateLoanAsLender(
        bytes32 indexed loanOrderHash,
        address indexed lender,
        uint256 loanTokenAmountAdded,
        uint256 loanTokenAmountFillable,
        uint256 expirationUnixTimestampSec
    );
}

contract BZxStorage is BZxObjects, BZxEvents, ReentrancyGuard, Ownable, GasTracker {
    uint256 internal constant MAX_UINT = 2**256 - 1;

    address public bZRxTokenContract;
    address public bZxEtherContract;
    address public wethContract;
    address payable public vaultContract;
    address public oracleRegistryContract;
    address public bZxTo0xContract;
    address public bZxTo0xV2Contract;
    bool public DEBUG_MODE = false;

    // Loan Orders
    mapping (bytes32 => LoanOrder) public orders; // mapping of loanOrderHash to on chain loanOrders
    mapping (bytes32 => LoanOrderAux) public orderAux; // mapping of loanOrderHash to on chain loanOrder auxiliary parameters
    mapping (bytes32 => uint256) public orderFilledAmounts; // mapping of loanOrderHash to loanTokenAmount filled
    mapping (bytes32 => uint256) public orderCancelledAmounts; // mapping of loanOrderHash to loanTokenAmount cancelled
    mapping (bytes32 => address) public orderLender; // mapping of loanOrderHash to lender (only one lender per order)

    // Loan Positions
    mapping (uint256 => LoanPosition) public loanPositions; // mapping of position ids to loanPositions
    mapping (bytes32 => mapping (address => uint256)) public loanPositionsIds; // mapping of loanOrderHash to mapping of trader address to position id

    // Lists
    mapping (address => bytes32[]) public orderList; // mapping of lenders and trader addresses to array of loanOrderHashes
    mapping (bytes32 => mapping (address => ListIndex)) public orderListIndex; // mapping of loanOrderHash to mapping of lenders and trader addresses to ListIndex objects

    mapping (bytes32 => uint256[]) public orderPositionList; // mapping of loanOrderHash to array of order position ids

    PositionRef[] public positionList; // array of loans that need to be checked for liquidation or expiration
    mapping (uint256 => ListIndex) public positionListIndex; // mapping of position ids to ListIndex objects

    // Interest
    mapping (address => mapping (address => uint256)) public tokenInterestOwed; // mapping of lender address to mapping of interest token address to amount of interest owed for all loans (assuming they go to full term)
    mapping (address => mapping (address => mapping (address => LenderInterest))) public lenderOracleInterest; // mapping of lender address to mapping of oracle to mapping of interest token to LenderInterest objects
    mapping (bytes32 => LenderInterest) public lenderOrderInterest; // mapping of loanOrderHash to LenderInterest objects
    mapping (uint256 => TraderInterest) public traderLoanInterest; // mapping of position ids to TraderInterest objects

    // Other Storage
    mapping (address => address) public oracleAddresses; // mapping of oracles to their current logic contract
    mapping (bytes32 => mapping (address => bool)) public preSigned; // mapping of hash => signer => signed
    mapping (address => mapping (address => bool)) public allowedValidators; // mapping of signer => validator => approved

    // General Purpose
    mapping (bytes => uint256) internal dbUint256;
    mapping (bytes => uint256[]) internal dbUint256Array;
    mapping (bytes => address) internal dbAddress;
    mapping (bytes => address[]) internal dbAddressArray;
    mapping (bytes => bool) internal dbBool;
    mapping (bytes => bool[]) internal dbBoolArray;
    mapping (bytes => bytes32) internal dbBytes32;
    mapping (bytes => bytes32[]) internal dbBytes32Array;
    mapping (bytes => bytes) internal dbBytes;
    mapping (bytes => bytes[]) internal dbBytesArray;
}

contract BZxProxiable {
    mapping (bytes4 => address) public targets;

    mapping (bytes4 => bool) public targetIsPaused;

    function initialize(address _target) public;
}

contract BZxProxy is BZxStorage, BZxProxiable {
    
    constructor(
        address _settings) 
        public
    {
        (bool result,) = _settings.delegatecall.gas(gasleft())(abi.encodeWithSignature("initialize(address)", _settings));
        require(result, "BZxProxy::constructor: failed");
    }
    
    function() 
        external
        payable 
    {
        require(!targetIsPaused[msg.sig], "BZxProxy::Function temporarily paused");

        address target = targets[msg.sig];
        require(target != address(0), "BZxProxy::Target not found");

        bytes memory data = msg.data;
        assembly {
            let result := delegatecall(gas, target, add(data, 0x20), mload(data), 0, 0)
            let size := returndatasize
            let ptr := mload(0x40)
            returndatacopy(ptr, 0, size)
            switch result
            case 0 { revert(ptr, size) }
            default { return(ptr, size) }
        }
    }

    function initialize(
        address)
        public
    {
        revert();
    }
}