// File: contracts/9_LendLocal_Gasreward.sol



// SPDX-License-Identifier: UNLICENSED
pragma solidity >=0.7.0 <0.9.0;

import "@chainlink/contracts/src/v0.8/interfaces/AggregatorV3Interface.sol";

// TODO(zx): Replace all instances of SafeMath with OZ implementation
library SafeMath {
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a, "SafeMath: addition overflow");

        return c;
    }

    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        return sub(a, b, "SafeMath: subtraction overflow");
    }

    function sub(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        require(b <= a, errorMessage);
        uint256 c = a - b;

        return c;
    }

    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;
    }

    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        return div(a, b, "SafeMath: division by zero");
    }

    function div(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        uint256 c = a / b;
        assert(a == b * c + (a % b)); // There is no case in which this doesn't hold

        return c;
    }

    // Only used in the  BondingCalculator.sol
    function sqrrt(uint256 a) internal pure returns (uint256 c) {
        if (a > 3) {
            c = a;
            uint256 b = add(div(a, 2), 1);
            while (b < c) {
                c = b;
                b = div(add(div(a, b), b), 2);
            }
        } else if (a != 0) {
            c = 1;
        }
    }
}

/// @title Base64
/// @author Brecht Devos - <brecht@loopring.org>
/// @notice Provides functions for encoding/decoding base64
library Base64 {
    string internal constant TABLE_ENCODE =
        "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
    bytes internal constant TABLE_DECODE =
        hex"0000000000000000000000000000000000000000000000000000000000000000"
        hex"00000000000000000000003e0000003f3435363738393a3b3c3d000000000000"
        hex"00000102030405060708090a0b0c0d0e0f101112131415161718190000000000"
        hex"001a1b1c1d1e1f202122232425262728292a2b2c2d2e2f303132330000000000";

    function encode(bytes memory data) internal pure returns (string memory) {
        if (data.length == 0) return "";

        // load the table into memory
        string memory table = TABLE_ENCODE;

        // multiply by 4/3 rounded up
        uint256 encodedLen = 4 * ((data.length + 2) / 3);

        // add some extra buffer at the end required for the writing
        string memory result = new string(encodedLen + 32);

        assembly {
            // set the actual output length
            mstore(result, encodedLen)

            // prepare the lookup table
            let tablePtr := add(table, 1)

            // input ptr
            let dataPtr := data
            let endPtr := add(dataPtr, mload(data))

            // result ptr, jump over length
            let resultPtr := add(result, 32)

            // run over the input, 3 bytes at a time
            for {

            } lt(dataPtr, endPtr) {

            } {
                // read 3 bytes
                dataPtr := add(dataPtr, 3)
                let input := mload(dataPtr)

                // write 4 characters
                mstore8(
                    resultPtr,
                    mload(add(tablePtr, and(shr(18, input), 0x3F)))
                )
                resultPtr := add(resultPtr, 1)
                mstore8(
                    resultPtr,
                    mload(add(tablePtr, and(shr(12, input), 0x3F)))
                )
                resultPtr := add(resultPtr, 1)
                mstore8(
                    resultPtr,
                    mload(add(tablePtr, and(shr(6, input), 0x3F)))
                )
                resultPtr := add(resultPtr, 1)
                mstore8(resultPtr, mload(add(tablePtr, and(input, 0x3F))))
                resultPtr := add(resultPtr, 1)
            }

            // padding with '='
            switch mod(mload(data), 3)
            case 1 {
                mstore(sub(resultPtr, 2), shl(240, 0x3d3d))
            }
            case 2 {
                mstore(sub(resultPtr, 1), shl(248, 0x3d))
            }
        }

        return result;
    }

    function decode(string memory _data) internal pure returns (bytes memory) {
        bytes memory data = bytes(_data);

        if (data.length == 0) return new bytes(0);
        require(data.length % 4 == 0, "invalid base64 decoder input");

        // load the table into memory
        bytes memory table = TABLE_DECODE;

        // every 4 characters represent 3 bytes
        uint256 decodedLen = (data.length / 4) * 3;

        // add some extra buffer at the end required for the writing
        bytes memory result = new bytes(decodedLen + 32);

        assembly {
            // padding with '='
            let lastBytes := mload(add(data, mload(data)))
            if eq(and(lastBytes, 0xFF), 0x3d) {
                decodedLen := sub(decodedLen, 1)
                if eq(and(lastBytes, 0xFFFF), 0x3d3d) {
                    decodedLen := sub(decodedLen, 1)
                }
            }

            // set the actual output length
            mstore(result, decodedLen)

            // prepare the lookup table
            let tablePtr := add(table, 1)

            // input ptr
            let dataPtr := data
            let endPtr := add(dataPtr, mload(data))

            // result ptr, jump over length
            let resultPtr := add(result, 32)

            // run over the input, 4 characters at a time
            for {

            } lt(dataPtr, endPtr) {

            } {
                // read 4 characters
                dataPtr := add(dataPtr, 4)
                let input := mload(dataPtr)

                // write 3 bytes
                let output := add(
                    add(
                        shl(
                            18,
                            and(
                                mload(add(tablePtr, and(shr(24, input), 0xFF))),
                                0xFF
                            )
                        ),
                        shl(
                            12,
                            and(
                                mload(add(tablePtr, and(shr(16, input), 0xFF))),
                                0xFF
                            )
                        )
                    ),
                    add(
                        shl(
                            6,
                            and(
                                mload(add(tablePtr, and(shr(8, input), 0xFF))),
                                0xFF
                            )
                        ),
                        and(mload(add(tablePtr, and(input, 0xFF))), 0xFF)
                    )
                )
                mstore(resultPtr, shl(232, output))
                resultPtr := add(resultPtr, 3)
            }
        }

        return result;
    }
}

/**
 * @dev Collection of functions related to the address type
 */
library Address {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize, which returns 0 for contracts in
        // construction, since the code is only stored at the end of the
        // constructor execution.

        uint256 size;
        // solhint-disable-next-line no-inline-assembly
        assembly {
            size := extcodesize(account)
        }
        return size > 0;
    }

    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(
            address(this).balance >= amount,
            "Address: insufficient balance"
        );

        // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
        (bool success, ) = recipient.call{value: amount}("");
        require(
            success,
            "Address: unable to send value, recipient may have reverted"
        );
    }

    /**
     * @dev Performs a Solidity function call using a low level `call`. A
     * plain`call` is an unsafe replacement for a function call: use this
     * function instead.
     *
     * If `target` reverts with a revert reason, it is bubbled up by this
     * function (like regular Solidity function calls).
     *
     * Returns the raw returned data. To convert to the expected return value,
     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
     *
     * Requirements:
     *
     * - `target` must be a contract.
     * - calling `target` with `data` must not revert.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data)
        internal
        returns (bytes memory)
    {
        return functionCall(target, data, "Address: low-level call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
     * `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but also transferring `value` wei to `target`.
     *
     * Requirements:
     *
     * - the calling contract must have an ETH balance of at least `value`.
     * - the called Solidity function must be `payable`.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value
    ) internal returns (bytes memory) {
        return
            functionCallWithValue(
                target,
                data,
                value,
                "Address: low-level call with value failed"
            );
    }

    /**
     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
     * with `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value,
        string memory errorMessage
    ) internal returns (bytes memory) {
        require(
            address(this).balance >= value,
            "Address: insufficient balance for call"
        );
        require(isContract(target), "Address: call to non-contract");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.call{value: value}(
            data
        );
        return _verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data)
        internal
        view
        returns (bytes memory)
    {
        return
            functionStaticCall(
                target,
                data,
                "Address: low-level static call failed"
            );
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        require(isContract(target), "Address: static call to non-contract");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.staticcall(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data)
        internal
        returns (bytes memory)
    {
        return
            functionDelegateCall(
                target,
                data,
                "Address: low-level delegate call failed"
            );
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        require(isContract(target), "Address: delegate call to non-contract");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.delegatecall(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }

    function _verifyCallResult(
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) private pure returns (bytes memory) {
        if (success) {
            return returndata;
        } else {
            // Look for revert reason and bubble it up if present
            if (returndata.length > 0) {
                // The easiest way to bubble the revert reason is using memory via assembly

                // solhint-disable-next-line no-inline-assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}

library SafeERC20 {
    using SafeMath for uint256;
    using Address for address;

    function safeTransfer(
        IERC20 token,
        address to,
        uint256 value
    ) internal {
        _callOptionalReturn(
            token,
            abi.encodeWithSelector(token.transfer.selector, to, value)
        );
    }

    function safeTransferFrom(
        IERC20 token,
        address from,
        address to,
        uint256 value
    ) internal {
        _callOptionalReturn(
            token,
            abi.encodeWithSelector(token.transferFrom.selector, from, to, value)
        );
    }

    /**
     * @dev Deprecated. This function has issues similar to the ones found in
     * {IERC20-approve}, and its usage is discouraged.
     *
     * Whenever possible, use {safeIncreaseAllowance} and
     * {safeDecreaseAllowance} instead.
     */
    function safeApprove(
        IERC20 token,
        address spender,
        uint256 value
    ) internal {
        // safeApprove should only be called when setting an initial allowance,
        // or when resetting it to zero. To increase and decrease it, use
        // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
        // solhint-disable-next-line max-line-length
        require(
            (value == 0) || (token.allowance(address(this), spender) == 0),
            "SafeBEP20: approve from non-zero to non-zero allowance"
        );
        _callOptionalReturn(
            token,
            abi.encodeWithSelector(token.approve.selector, spender, value)
        );
    }

    function safeIncreaseAllowance(
        IERC20 token,
        address spender,
        uint256 value
    ) internal {
        uint256 newAllowance = token.allowance(address(this), spender).add(
            value
        );
        _callOptionalReturn(
            token,
            abi.encodeWithSelector(
                token.approve.selector,
                spender,
                newAllowance
            )
        );
    }

    function safeDecreaseAllowance(
        IERC20 token,
        address spender,
        uint256 value
    ) internal {
        uint256 newAllowance = token.allowance(address(this), spender).sub(
            value,
            "SafeBEP20: decreased allowance below zero"
        );
        _callOptionalReturn(
            token,
            abi.encodeWithSelector(
                token.approve.selector,
                spender,
                newAllowance
            )
        );
    }

    /**
     * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
     * on the return value: the return value is optional (but if data is returned, it must not be false).
     * @param token The token targeted by the call.
     * @param data The call data (encoded using abi.encode or one of its variants).
     */
    function _callOptionalReturn(IERC20 token, bytes memory data) private {
        // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
        // we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that
        // the target address contains contract code and also asserts for success in the low-level call.

        bytes memory returndata = address(token).functionCall(
            data,
            "SafeBEP20: low-level call failed"
        );
        if (returndata.length > 0) {
            // Return data is optional
            // solhint-disable-next-line max-line-length
            require(
                abi.decode(returndata, (bool)),
                "SafeBEP20: BEP20 operation did not succeed"
            );
        }
    }
}

interface IERC20 {
    function increaseAllowance(address spender, uint256 addedValue)
        external
        returns (bool);

    function decimals() external view returns (uint8);

    function totalSupply() external view returns (uint256);

    function balanceOf(address account) external view returns (uint256);

    function transfer(address recipient, uint256 amount)
        external
        returns (bool);

    function allowance(address owner, address spender)
        external
        view
        returns (uint256);

    function approve(address spender, uint256 amount) external returns (bool);

    function transferFrom(
        address sender,
        address recipient,
        uint256 amount
    ) external returns (bool);

    event Transfer(address indexed from, address indexed to, uint256 value);

    event Approval(
        address indexed owner,
        address indexed spender,
        uint256 value
    );
}

interface ISpotPrice {
    function getRateToEth(IERC20 srcToken, bool useSrcWrappers)
        external
        view
        returns (uint256 weightedRate);

    function getRate(
        IERC20 srcToken,
        IERC20 dstToken,
        bool useWrappers
    ) external view returns (uint256 weightedRate);
}

abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes calldata) {
        this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
        return msg.data;
    }
}

contract Ownable is Context {
    address private _owner;

    event OwnershipTransferred(
        address indexed previousOwner,
        address indexed newOwner
    );

    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    constructor() {
        address msgSender = _msgSender();
        _owner = msgSender;
        emit OwnershipTransferred(address(0), msgSender);
    }

    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view returns (address) {
        return _owner;
    }

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        require(_owner == _msgSender(), "Ownable: caller is not the owner");
        _;
    }

    /**
     * @dev Leaves the contract without owner. It will not be possible to call
     * `onlyOwner` functions anymore. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby removing any functionality that is only available to the owner.
     */
    function renounceOwnership() public virtual onlyOwner {
        emit OwnershipTransferred(_owner, address(0));
        _owner = address(0);
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Can only be called by the current owner.
     */
    function transferOwnership(address newOwner) public virtual onlyOwner {
        require(
            newOwner != address(0),
            "Ownable: new owner is the zero address"
        );
        emit OwnershipTransferred(_owner, newOwner);
        _owner = newOwner;
    }
}

/**
 * @dev Contract module that helps prevent reentrant calls to a function.
 *
 * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
 * available, which can be applied to functions to make sure there are no nested
 * (reentrant) calls to them.
 *
 * Note that because there is a single `nonReentrant` guard, functions marked as
 * `nonReentrant` may not call one another. This can be worked around by making
 * those functions `private`, and then adding `external` `nonReentrant` entry
 * points to them.
 *
 * TIP: If you would like to learn more about reentrancy and alternative ways
 * to protect against it, check out our blog post
 * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
 */
contract ReentrancyGuard {
    // Booleans are more expensive than uint256 or any type that takes up a full
    // word because each write operation emits an extra SLOAD to first read the
    // slot's contents, replace the bits taken up by the boolean, and then write
    // back. This is the compiler's defense against contract upgrades and
    // pointer aliasing, and it cannot be disabled.

    // The values being non-zero value makes deployment a bit more expensive,
    // but in exchange the refund on every call to nonReentrant will be lower in
    // amount. Since refunds are capped to a percentage of the total
    // transaction's gas, it is best to keep them low in cases like this one, to
    // increase the likelihood of the full refund coming into effect.
    uint256 private constant _NOT_ENTERED = 1;
    uint256 private constant _ENTERED = 2;

    uint256 private _status;

    constructor() {
        _status = _NOT_ENTERED;
    }

    /**
     * @dev Prevents a contract from calling itself, directly or indirectly.
     * Calling a `nonReentrant` function from another `nonReentrant`
     * function is not supported. It is possible to prevent this from happening
     * by making the `nonReentrant` function external, and make it call a
     * `private` function that does the actual work.
     */
    modifier nonReentrant() {
        // On the first call to nonReentrant, _notEntered will be true
        require(_status != _ENTERED, "ReentrancyGuard: reentrant call");

        // Any calls to nonReentrant after this point will fail
        _status = _ENTERED;

        _;

        // By storing the original value once again, a refund is triggered (see
        // https://eips.ethereum.org/EIPS/eip-2200)
        _status = _NOT_ENTERED;
    }
}

contract LendLocal is Ownable, ReentrancyGuard {
    using SafeMath for uint256;
    using SafeERC20 for IERC20;

    struct LoanRequest {
        address borrower;
        address collateralToken;
        uint256 kiosk;
        uint256 loanAmount;
        uint256 collateralAmountReal;
        uint256 collateralAmountApproved;
        uint256 loanDueDate;
        uint256 duration;
        uint32 loanId;
        string withdrawCode;
        string returnCode;
        bool isPayback;
        bool isFiatPaid;
        bool isTaken;
    }

    uint256 public DURATION = 31536000;
    uint256 public MAX_LOAN = 10000 ether; // consider fiat(USD) decimals as 18, MAX_LOAN:: 10000 USD
    uint256 public MIN_LOAN = 10 ether; // consider fiat(USD) decimals as 18, MIN_LOAN:: 10 USD

    uint32 public totalLoanCount = 0;
    uint256 public totalLoaned = 0;
    uint256 public currentLoaned = 0;
    address public ETHER;
    address public ETHUSD_PRICEFEED;
    address public operator;
    address[] public loanUsers;

    mapping(address => bool) public isUseWrapper;
    mapping(address => bool) public isSafeTransfer;
    mapping(address => bool) public isBlockedToken;
    mapping(address => bool) public isBlockedUser;
    mapping(address => uint32) public userLoansCount;
    mapping(address => mapping(uint32 => uint32)) userLoanIds;
    mapping(uint32 => LoanRequest) public loans;

    ISpotPrice public spotPrice;

    event NewRequestLoan(
        address indexed borrower,
        address indexed collateralToken,
        uint256 collateralAmountApproved,
        uint256 kiosk,
        uint256 loanDueDate,
        uint256 duration,
        uint256 indexed loanId
    );

    event NewApproveLoan(
        uint256 indexed loanId,
        address indexed borrower,
        address indexed collateralToken,
        uint256 collateralAmountApproved,
        uint256 collateralAmountReal,
        uint256 fiatAmountReal
    );

    event NewLoanEther(
        address indexed borrower,
        address indexed collateralToken,
        uint256 collateralAmount,
        uint256 kiosk,
        uint256 loanAmount,
        uint256 loanDueDate,
        uint256 duration,
        uint256 loanId
    );

    event PayBack(
        address borrower,
        bool paybackSuccess,
        uint256 paybackTime,
        uint256 collateralAmount
    );
    event Received(address, uint256);
    event NewAddFiatPool(address priceFeed);
    event NewRemoveFiatPool(uint256 id);
    event NewUpdatePriceFeed(uint256 id, address priceFeed);
    event NewCloseFiatPool(uint256 id, bool closed);

    constructor(
        address _spotPriceAddress,
        address _weth,
        address _ethUSDPriceFeed
    ) {
        require(_weth != address(0), "zero weth address");
        operator = msg.sender;
        ISpotPrice _spotPrice = ISpotPrice(_spotPriceAddress);
        spotPrice = _spotPrice;
        ETHER = _weth;
        ETHUSD_PRICEFEED = _ethUSDPriceFeed;
    }

    // Operator CAN do modifier
    modifier onlyOperator() {
        require(operator == msg.sender, "operator: caller is not the operator");
        _;
    }

    modifier onlyOwnerOrOperator() {
        require(
            (msg.sender == owner()) || (msg.sender == operator),
            "Not owner or operator"
        );
        _;
    }

    receive() external payable {
        emit Received(msg.sender, msg.value);
    }

    function uintToBytes(uint256 _value, uint256 _length)
        private
        pure
        returns (bytes memory)
    {
        bytes memory reversed = new bytes(_length);
        uint256 i = _length;
        while (_value != 0) {
            i--;
            bytes1 bb = bytes1(uint8(_value));
            _value >>= 4;
            reversed[i] = bb;
        }
        return reversed;
    }

    function getEncodeValue(bytes memory data)
        private
        pure
        returns (string memory)
    {
        string memory encodedValue = Base64.encode(data);
        return encodedValue;
    }

    function getDecodeValue(string memory data)
        private
        pure
        returns (bytes memory)
    {
        bytes memory decodedValue = Base64.decode(data);
        return decodedValue;
    }

    function getETHPriceInUSD() public view returns (uint256) {
        AggregatorV3Interface priceFeed = AggregatorV3Interface(
            ETHUSD_PRICEFEED
        );
        (
            ,
            /*uint80 roundID*/
            int256 price, /*uint startedAt*/ /*uint timeStamp*/ /*uint80 answeredInRound*/
            ,
            ,

        ) = priceFeed.latestRoundData();
        // ETH price decimal is 8
        return uint256(price);
    }

    function getTokenPriceInUSD(address _collateralToken, bool _useWrapper)
        public
        view
        returns (uint256)
    {
        bool isBlocked = isBlockedToken[_collateralToken];
        require(!isBlocked, "tokenPrice:: Token is Blocked");
        uint256 ethPrice = getETHPriceInUSD();
        if (_collateralToken == ETHER) {
            return ethPrice.mul(10**10); // eth price decimal is 18
        } else {
            uint256 decimals = IERC20(_collateralToken).decimals();
            uint256 rateToEth = spotPrice
                .getRateToEth(IERC20(_collateralToken), _useWrapper)
                .mul(10**decimals)
                .div(10**18); // rateToEth decimal is 18
            uint256 result = rateToEth.mul(ethPrice).div(10**8); // token price decimal is 18
            return result;
        }
    }

    // calculate require colleteral token amount by passing fiat amount
    function countCollateralFromFiat(
        address _collateralToken,
        uint256 _fiatAmount
    ) public view returns (uint256) {
        bool bUseWrapper = isUseWrapper[_collateralToken];
        uint256 tokenPrice = getTokenPriceInUSD(_collateralToken, bUseWrapper);
        uint256 tokenDecimals = IERC20(_collateralToken).decimals();
        // fiatAmount decimal 18, token price decimal 18
        uint256 result = _fiatAmount.mul(10**tokenDecimals).div(tokenPrice);
        return result;
    }

    // calculate require fiat amount by passing collateral amount
    function countFiatFromCollateral(
        address _collateralToken,
        uint256 _colTokenAmount
    ) public view returns (uint256) {
        bool bUseWrapper = isUseWrapper[_collateralToken];
        uint256 tokenPrice = getTokenPriceInUSD(_collateralToken, bUseWrapper);
        uint256 tokenDecimals = IERC20(_collateralToken).decimals();
        // fiatAmount decimal 18, token price decimal 18
        uint256 result = _colTokenAmount.mul(tokenPrice).div(10**tokenDecimals);
        return result;
    }

    function TokenTransfer(
        address _user,
        address _token,
        uint256 _tokenAmount
    ) private returns (bool) {
        if (!isSafeTransfer[_token]) {
            bool transferred = IERC20(_token).transferFrom(
                _user,
                address(this),
                _tokenAmount
            );
            return transferred;
        } else {
            IERC20(_token).safeTransferFrom(_user, address(this), _tokenAmount);
            return true;
        }
    }

    function requestLoanToken(
        address _collateralToken,
        uint256 _kiosk,
        uint256 _collateralAmount
    ) external nonReentrant {
        bool isBlocked = isBlockedToken[_collateralToken];
        bool isUserBlocked = isBlockedUser[msg.sender];
        require(!isBlocked, "requestLoan:: Token is blocked");
        require(!isUserBlocked, "requestLoan:: User is blocked");
        address collateralToken = _collateralToken;
        uint256 collateralAmount = _collateralAmount;
        uint256 currentAllowance = IERC20(collateralToken).allowance(msg.sender, address(this));
        require(currentAllowance >= collateralAmount, "requestLoan:: collateral token allowance is not enough");
        LoanRequest memory newLoan;
        newLoan.borrower = msg.sender;
        newLoan.collateralToken = collateralToken;
        newLoan.kiosk = _kiosk;
        newLoan.collateralAmountApproved = collateralAmount;
        newLoan.loanId = totalLoanCount;
        newLoan.isPayback = false;
        newLoan.isFiatPaid = false;
        newLoan.loanDueDate = block.timestamp + DURATION;
        newLoan.duration = DURATION;

        uint32 tempCount = userLoansCount[msg.sender];
        loans[totalLoanCount] = newLoan;
        userLoanIds[msg.sender][tempCount] = totalLoanCount;
        userLoansCount[msg.sender]++;
        totalLoanCount++;
    }

    function approveLoan(uint32 _loanId)
        public
        nonReentrant
        onlyOwnerOrOperator
    {
        LoanRequest memory loanReq = loans[_loanId];
        address collateralToken = loanReq.collateralToken;

        require(!loanReq.isTaken, "approveLoan:: Take token already");
        require(
            collateralToken != ETHER,
            "approveLoan:: collateral token is ETHER"
        );

        address tempBorrower = loanReq.borrower;
        uint32 loanId = loanReq.loanId;
        uint256 startTimestamp = loanReq.loanDueDate - loanReq.duration;
        uint256 collateralAmount = loanReq.collateralAmountApproved;
        uint256 beforeBalance = IERC20(collateralToken).balanceOf(address(this));
        TokenTransfer(tempBorrower, collateralToken, collateralAmount);
        // bool isSafe = isSafeTransfer[collateralToken];
        // if(!isSafe) {
        //     IERC20(collateralToken).transferFrom(msg.sender, address(this), collateralAmount);
        // } else {
        //     IERC20(collateralToken).safeTransferFrom(msg.sender, address(this), collateralAmount);
        // }
        uint256 afterBalance = IERC20(collateralToken).balanceOf(address(this));
        uint256 collateralAmountReal = afterBalance - beforeBalance;
        uint256 fiatAmountReal = countFiatFromCollateral(
            collateralToken,
            collateralAmountReal
        );
        bool isOldUser = false;
        for (uint256 i = 0; i < loanUsers.length; i++) {
            if (loanUsers[i] == tempBorrower) {
                isOldUser = true;
                break;
            }
        }
        if (isOldUser == false) {
            loanUsers.push(tempBorrower);
        }

        bytes memory wTemp = uintToBytes(loanId, 4);
        string memory wCode = getEncodeValue(wTemp);

        uint64 returnValue = getReturnValue(loanId, startTimestamp);
        bytes memory rTemp = uintToBytes(returnValue, 8);
        string memory rCode = getEncodeValue(rTemp);

        totalLoaned = totalLoaned + fiatAmountReal;
        currentLoaned = currentLoaned + fiatAmountReal;

        loans[loanId].collateralAmountReal = collateralAmountReal;
        loans[loanId].loanAmount = fiatAmountReal;
        loans[loanId].withdrawCode = wCode;
        loans[loanId].returnCode = rCode;
        loans[loanId].isTaken = true;

        emit NewApproveLoan(
            loanId,
            tempBorrower,
            collateralToken,
            collateralAmount,
            collateralAmountReal,
            fiatAmountReal
        );
    }

    function approveLoanEx(uint32 _loanId)
        external
        nonReentrant
        onlyOwnerOrOperator
    {
        LoanRequest memory loanReq = loans[_loanId];
        address collateralToken = loanReq.collateralToken;

        require(!loanReq.isTaken, "approveLoan:: Take token already");
        require(
            collateralToken != ETHER,
            "approveLoan:: collateral token is ETHER"
        );

        address tempBorrower = loanReq.borrower;
        uint32 loanId = loanReq.loanId;
        uint256 startTimestamp = loanReq.loanDueDate - loanReq.duration;
        uint256 collateralAmount = loanReq.collateralAmountApproved;
        uint256 beforeBalance = IERC20(collateralToken).balanceOf(address(this));
        TokenTransfer(tempBorrower, collateralToken, collateralAmount);
        // bool isSafe = isSafeTransfer[collateralToken];
        // if(!isSafe) {
        //     IERC20(collateralToken).transferFrom(msg.sender, address(this), collateralAmount);
        // } else {
        //     IERC20(collateralToken).safeTransferFrom(msg.sender, address(this), collateralAmount);
        // }
        uint256 afterBalance = IERC20(collateralToken).balanceOf(address(this));
        uint256 collateralAmountReal = afterBalance - beforeBalance;
        uint256 fiatAmountReal = countFiatFromCollateral(
            collateralToken,
            collateralAmountReal
        );
        bool isOldUser = false;
        for (uint256 i = 0; i < loanUsers.length; i++) {
            if (loanUsers[i] == tempBorrower) {
                isOldUser = true;
                break;
            }
        }
        if (isOldUser == false) {
            loanUsers.push(tempBorrower);
        }

        bytes memory wTemp = uintToBytes(loanId, 4);
        string memory wCode = getEncodeValue(wTemp);

        uint64 returnValue = getReturnValue(loanId, startTimestamp);
        bytes memory rTemp = uintToBytes(returnValue, 8);
        string memory rCode = getEncodeValue(rTemp);

        totalLoaned = totalLoaned + fiatAmountReal;
        currentLoaned = currentLoaned + fiatAmountReal;

        loans[loanId].collateralAmountReal = collateralAmountReal;
        loans[loanId].loanAmount = fiatAmountReal;
        loans[loanId].withdrawCode = wCode;
        loans[loanId].returnCode = rCode;
        loans[loanId].isTaken = true;

        emit NewApproveLoan(
            loanId,
            tempBorrower,
            collateralToken,
            collateralAmount,
            collateralAmountReal,
            fiatAmountReal
        );
    }

    function approveLoanSim(uint32 _loanId)
        external
        nonReentrant
        onlyOwnerOrOperator
    {
        LoanRequest memory loanReq = loans[_loanId];
        address collateralToken = loanReq.collateralToken;

        require(!loanReq.isTaken, "approveLoan:: Take token already");
        require(
            collateralToken != ETHER,
            "approveLoan:: collateral token is ETHER"
        );

        address tempBorrower = loanReq.borrower;
        uint32 loanId = loanReq.loanId;
        uint256 startTimestamp = loanReq.loanDueDate - loanReq.duration;
        uint256 collateralAmount = loanReq.collateralAmountApproved;
        uint256 beforeBalance = IERC20(collateralToken).balanceOf(address(this));
        TokenTransfer(tempBorrower, collateralToken, collateralAmount);
        // bool isSafe = isSafeTransfer[collateralToken];
        // if(!isSafe) {
        //     IERC20(collateralToken).transferFrom(tempBorrower, address(this), collateralAmount);
        // } else {
        //     IERC20(collateralToken).safeTransferFrom(tempBorrower, address(this), collateralAmount);
        // }
        uint256 afterBalance = IERC20(collateralToken).balanceOf(address(this));
        uint256 collateralAmountReal = afterBalance - beforeBalance;
        uint256 fiatAmountReal = countFiatFromCollateral(
            collateralToken,
            collateralAmountReal
        );

        bytes memory wTemp = uintToBytes(loanId, 4);
        string memory wCode = getEncodeValue(wTemp);

        uint64 returnValue = getReturnValue(loanId, startTimestamp);
        bytes memory rTemp = uintToBytes(returnValue, 8);
        string memory rCode = getEncodeValue(rTemp);

        totalLoaned = totalLoaned + fiatAmountReal;
        currentLoaned = currentLoaned + fiatAmountReal;

        loans[loanId].collateralAmountReal = collateralAmountReal;
        loans[loanId].loanAmount = fiatAmountReal;
        loans[loanId].withdrawCode = wCode;
        loans[loanId].returnCode = rCode;
        loans[loanId].isTaken = true;

    }

    function loanEther(uint256 _kiosk) external payable nonReentrant {
        address collateralToken = ETHER;
        bool isBlocked = isBlockedToken[collateralToken];
        require(!isBlocked, "loanEther:: Token is blocked");

        uint256 collateralAmountReal = msg.value;
        uint256 fiatAmountReal = countFiatFromCollateral(
            collateralToken,
            collateralAmountReal
        );
        bool isOldUser = false;
        for (uint256 i = 0; i < loanUsers.length; i++) {
            if (loanUsers[i] == msg.sender) {
                isOldUser = true;
                break;
            }
        }
        if (isOldUser == false) {
            loanUsers.push(msg.sender);
        }
        LoanRequest memory newLoan;
        newLoan.borrower = msg.sender;
        newLoan.collateralToken = collateralToken;
        newLoan.kiosk = _kiosk;
        newLoan.loanAmount = fiatAmountReal;
        newLoan.collateralAmountReal = collateralAmountReal;
        newLoan.loanId = userLoansCount[msg.sender];
        newLoan.isPayback = false;
        newLoan.isFiatPaid = false;
        newLoan.isTaken = true;
        newLoan.loanDueDate = block.timestamp + DURATION;
        newLoan.duration = DURATION;
        uint256 startTimestamp = newLoan.loanDueDate - DURATION;

        bytes memory temp = uintToBytes(newLoan.loanId, 4);
        string memory wCode = getEncodeValue(temp);
        newLoan.withdrawCode = wCode;

        uint64 returnValue = getReturnValue(newLoan.loanId, startTimestamp);
        temp = uintToBytes(returnValue, 8);
        string memory rCode = getEncodeValue(temp);
        newLoan.returnCode = rCode;

        uint32 tempCount = userLoansCount[msg.sender];
        loans[totalLoanCount] = newLoan;
        userLoanIds[msg.sender][tempCount] = totalLoanCount;
        userLoansCount[msg.sender]++;
        totalLoanCount++;

        totalLoaned = totalLoaned + fiatAmountReal;
        currentLoaned = currentLoaned + fiatAmountReal;

        emit NewLoanEther(
            newLoan.borrower,
            newLoan.collateralToken,
            newLoan.collateralAmountReal,
            newLoan.kiosk,
            newLoan.loanAmount,
            newLoan.loanDueDate,
            newLoan.duration,
            newLoan.loanId
        );
    }

    function payback(uint32 _id) public nonReentrant {
        LoanRequest storage loanReq = loans[_id];
        address collateralToken = loanReq.collateralToken;
        uint256 collateralAmount = loanReq.collateralAmountReal;
        uint256 fiatAmount = loanReq.loanAmount;
        bool isFiatPaid = loanReq.isFiatPaid;
        require(
            loanReq.borrower == msg.sender,
            "payback: Only borrower can payback"
        );
        bool isUserBlocked = isBlockedUser[loanReq.borrower];
        require(!isUserBlocked, "requestLoan:: User is blocked");
        require(!loanReq.isPayback, "payback: Payback already");
        require(
            block.timestamp <= loanReq.loanDueDate,
            "payback: Exceed due date"
        );
        require(isFiatPaid, "payback: Fiat is not paid");
        loanReq.isPayback = true;
        if (collateralToken == ETHER) {
            address payable to = payable(msg.sender);
            to.transfer(collateralAmount);
        } else {
            if (isSafeTransfer[collateralToken]) {
                IERC20(collateralToken).safeTransfer(
                    msg.sender,
                    collateralAmount
                );
            } else {
                require(
                    IERC20(collateralToken).transfer(
                        msg.sender,
                        collateralAmount
                    ),
                    "payback: Transfer collateral from contract to user failed"
                );
            }
        }
        currentLoaned = currentLoaned - fiatAmount;
        emit PayBack(
            msg.sender,
            loanReq.isPayback,
            block.timestamp,
            collateralAmount
        );
    }

    function setFiatPaidUser(address _user, uint32 _id)
        public
        onlyOwnerOrOperator
    {
        uint32 loanId = userLoanIds[_user][_id];
        LoanRequest storage loanReq = loans[loanId];
        require(loanReq.borrower == _user, "setFiat: Invalid user address");
        loanReq.isFiatPaid = true;
    }

    function setFiatPaid(uint32 _loanId) public onlyOwnerOrOperator {
        LoanRequest storage loanReq = loans[_loanId];
        loanReq.isFiatPaid = true;
    }

    function setSafeTransfer(address _token, bool _bool)
        external
        onlyOwnerOrOperator
    {
        isSafeTransfer[_token] = _bool;
    }

    function setTokenBlock(address _token, bool _bool)
        external
        onlyOwnerOrOperator
    {
        isBlockedToken[_token] = _bool;
    }

    function setUserBlock(address _user, bool _bool)
        external
        onlyOwnerOrOperator
    {
        isBlockedUser[_user] = _bool;
    }

    function setUseWrapper(address _token, bool _bool)
        external
        onlyOwnerOrOperator
    {
        isUseWrapper[_token] = _bool;
    }

    function getTokenBlocked(address _token) external view {
        bool _isBlocked;
        _isBlocked = isBlockedToken[_token];
    }

    function updateInfo(
        uint256 _duration,
        uint256 _maxLoan,
        uint256 _minLoan
    ) external onlyOwnerOrOperator {
        DURATION = _duration;
        MAX_LOAN = _maxLoan;
        MIN_LOAN = _minLoan;
    }

    function getReturnValue(uint32 _loanId, uint256 _startTimestamp)
        public
        pure
        returns (uint64)
    {
        uint64 tempTimestamp = uint64(_startTimestamp);
        return uint64(_loanId << 32) | tempTimestamp;
    }

    function getAllUserLoans(address _user)
        external
        view
        returns (LoanRequest[] memory)
    {
        LoanRequest[] memory requests = new LoanRequest[](
            userLoansCount[_user]
        );
        for (uint32 i = 0; i < userLoansCount[_user]; i++) {
            requests[i] = loans[i];
        }
        return requests;
    }

    function transferOperator(address _opeator) public onlyOwner {
        require(_opeator != address(0), "operator: Zero Address");
        operator = _opeator;
    }

    function withdrawEth(uint256 _amount) external onlyOwnerOrOperator {
        uint256 totalEth = address(this).balance;
        require(
            _amount <= totalEth,
            "withdraw: Can't exceed more than totalLiquidity"
        );
        address payable _owner = payable(msg.sender);
        _owner.transfer(_amount);
    }

    function recoverERC20(
        address _token,
        uint256 _amount,
        address _wallet
    ) external onlyOwnerOrOperator {
        require(_wallet != address(0), "recover:: address zero");
        if (isSafeTransfer[_token]) {
            IERC20(_token).safeTransfer(_wallet, _amount);
        } else {
            IERC20(_token).transfer(_wallet, _amount);
        }
    }

    function getTotalLoanedUsers() public view returns (uint256) {
        return loanUsers.length;
    }
}

// File: @chainlink/contracts/src/v0.8/interfaces/AggregatorV3Interface.sol



// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

interface AggregatorV3Interface {
  function decimals() external view returns (uint8);

  function description() external view returns (string memory);

  function version() external view returns (uint256);

  function getRoundData(uint80 _roundId)
    external
    view
    returns (
      uint80 roundId,
      int256 answer,
      uint256 startedAt,
      uint256 updatedAt,
      uint80 answeredInRound
    );

  function latestRoundData()
    external
    view
    returns (
      uint80 roundId,
      int256 answer,
      uint256 startedAt,
      uint256 updatedAt,
      uint80 answeredInRound
    );
}