// File: contracts/XSD/Pools/Arbitrage.sol



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

import './CollateralPool.sol';
import './Interfaces/IXSDWETHpool.sol';
import './Interfaces/IBankXWETHpool.sol';
import '../XSDStablecoin.sol';
import '../../UniswapFork/Interfaces/IRouter.sol';
import "./CollateralPoolLibrary.sol";
import '../../Oracle/Interfaces/IPIDController.sol';
import "../../BankX/BankXToken.sol";

contract Arbitrage is ReentrancyGuard{
    address public xsd_address;
    address public bankx_address;
    address public smartcontract_owner;
    address public router_address;
    address public pid_address;
    address public collateral_pool;
    address public xsd_pool;
    address public bankx_pool;
    address public origin_address;

    uint public arbitrage_paused;
    uint public last_update;
    uint public block_delay;
    bool public pause_arbitrage;

    XSDStablecoin private XSD;
    BankXToken private BankX;
    IPIDController private pid_controller;
    IRouter private Router;

constructor(
        address _xsd_address,
        address _bankx_address,
        address _collateral_pool,
        address _router_address,
        address _pid_controller,
        address _xsd_pool,
        address _bankx_pool,
        address _origin_address,
        address _smartcontract_owner,
        uint _block_delay
    ) {
        require((_smartcontract_owner != address(0))
            && (_origin_address != address(0))
            && (_collateral_pool != address(0))
            && (_xsd_pool != address(0))
            && (_bankx_pool != address(0))
            && (_router_address != address(0))
            && (_xsd_address != address(0))
            && (_bankx_address != address(0))
            && (_pid_controller != address(0))
            , "Zero address detected");
        xsd_address = _xsd_address;
        XSD = XSDStablecoin(_xsd_address);
        bankx_address = _bankx_address;
        BankX = BankXToken(_bankx_address);
        collateral_pool = _collateral_pool;
        router_address = _router_address;
        Router = IRouter(_router_address);
        pid_address = _pid_controller;
        pid_controller = IPIDController(_pid_controller);
        smartcontract_owner = _smartcontract_owner;
        origin_address = _origin_address;
        bankx_pool = _bankx_pool;
        xsd_pool = _xsd_pool;
        block_delay = _block_delay;
    }

function burnBankX(uint256 bankx_amount,uint256 eth_min_amount, uint256 bankx_min_amount, uint256 deadline) external nonReentrant {
    require(pause_arbitrage, "Arbitrage Paused");
    require(((pid_controller.lastPriceCheck(msg.sender).lastpricecheck+(block_delay)) <= block.number) && (pid_controller.lastPriceCheck(msg.sender).pricecheck), "Must wait for block_delay blocks");
    uint256 time_elapsed = block.timestamp - last_update;
    require(time_elapsed >= arbitrage_paused, "internal cooldown not passed");
    uint256 bankx_price = pid_controller.bankx_updated_price();
    uint256 xag_usd_price = XSD.xag_usd_price();
    uint silver_price = (xag_usd_price*(1e4))/(311035);
    require(pid_controller.xsd_updated_price()>(silver_price + (silver_price/1e3)), "BurnBankX:ARBITRAGE ERROR");
    (uint256 xsd_amount) = CollateralPoolLibrary.calcMintAlgorithmicXSD(
    bankx_price, 
    xag_usd_price,
    bankx_amount
    );
    BankX.pool_burn_from(msg.sender, bankx_amount);
    XSD.pool_mint(msg.sender, xsd_amount);
    Router.swapXSDForBankX(xsd_amount,msg.sender, eth_min_amount, bankx_min_amount,deadline);
    pid_controller.lastPriceCheck(msg.sender).pricecheck = false;
    last_update = block.timestamp;
    pid_controller.systemCalculations();
}

function burnXSD(uint256 XSD_amount,uint256 eth_min_amount, uint256 xsd_min_amount, uint256 deadline) external nonReentrant {
    require(pause_arbitrage, "Arbitrage Paused");
    require(((pid_controller.lastPriceCheck(msg.sender).lastpricecheck+(block_delay)) <= block.number) && (pid_controller.lastPriceCheck(msg.sender).pricecheck), "Must wait for block_delay blocks");
    uint256 time_elapsed = block.timestamp - last_update;
    require(time_elapsed >= arbitrage_paused, "internal cooldown not passed");
    uint256 xag_usd_price = XSD.xag_usd_price();
    uint silver_price = (xag_usd_price*(1e4))/(311035); 
    require(pid_controller.xsd_updated_price()<(silver_price - (silver_price/1e3)), "BurnXSD:ARBITRAGE ERROR");
    uint256 bankx_dollar_value_d18 = (XSD_amount*xag_usd_price)/(31103477); 
    uint256 bankx_amount = (bankx_dollar_value_d18*(1e6))/pid_controller.bankx_updated_price();
    if(XSD.totalSupply()>CollateralPool(payable(collateral_pool)).collat_XSD()){
        XSD.pool_burn_from(msg.sender,XSD_amount);    }
    else{
        TransferHelper.safeTransferFrom(xsd_address, msg.sender,origin_address, XSD_amount);
    }
    BankX.pool_mint(msg.sender, bankx_amount);
    Router.swapBankXForXSD(bankx_amount,msg.sender, eth_min_amount, xsd_min_amount,deadline);
    pid_controller.lastPriceCheck(msg.sender).pricecheck = false;
    last_update = block.timestamp;
    pid_controller.systemCalculations();
}
function setArbitrageCooldown(uint sec) external {
    require(msg.sender == smartcontract_owner, "Only the owner can access this function");
    arbitrage_paused = block.timestamp + sec;
}
function pauseArbitrage() external {
    require(msg.sender == smartcontract_owner, "Only the owner can access this function");
    pause_arbitrage = !pause_arbitrage;
}
function setSmartContractOwner(address _smartcontract_owner) external{
        require(msg.sender == smartcontract_owner, "Only the smart contract owner can access this function");
        require(_smartcontract_owner != address(0), "Zero address detected");
        smartcontract_owner = _smartcontract_owner;
    }

function renounceOwnership() external{
    require(msg.sender == smartcontract_owner, "Only the smart contract owner can access this function");
    smartcontract_owner = address(0);
}

function resetAddresses(address _xsd_address,
        address _bankx_address,
        address _collateral_pool,
        address _router_address,
        address _pid_controller,
        address _xsd_pool,
        address _bankx_pool,
        address _origin_address,
        address _smartcontract_owner, 
        uint _block_delay) external{
    require(msg.sender == smartcontract_owner, "Only the smart contract owner can access this function");
    require((_smartcontract_owner != address(0))
            && (_origin_address != address(0))
            && (_collateral_pool != address(0))
            && (_xsd_pool != address(0))
            && (_bankx_pool != address(0))
            && (_router_address != address(0))
            && (_xsd_address != address(0))
            && (_bankx_address != address(0))
            && (_pid_controller != address(0))
            , "Zero address detected");
        xsd_address = _xsd_address;
        XSD = XSDStablecoin(_xsd_address);
        bankx_address = _bankx_address;
        BankX = BankXToken(_bankx_address);
        collateral_pool = _collateral_pool;
        router_address = _router_address;
        Router = IRouter(_router_address);
        pid_address = _pid_controller;
        pid_controller = IPIDController(_pid_controller);
        smartcontract_owner = _smartcontract_owner;
        origin_address = _origin_address;
        bankx_pool = _bankx_pool;
        xsd_pool = _xsd_pool;
        block_delay = _block_delay;
}
}
// File: contracts/XSD/Pools/CollateralPool.sol




// SPDX-License-Identifier: MIT
/*
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  B::::BBBBBB:::::B      aaaaaaa:::::a   n:::::nnnn:::::n  k::::::k:::::k       X:::::::::X
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*/
pragma solidity ^0.8.0;

import '@uniswap/lib/contracts/libraries/TransferHelper.sol';
import '@openzeppelin/contracts/security/ReentrancyGuard.sol';
import "../../BankX/BankXToken.sol";
import "../XSDStablecoin.sol";
import "./Interfaces/IBankXWETHpool.sol";
import "./Interfaces/IXSDWETHpool.sol";
import '../../Oracle/Interfaces/IPIDController.sol';
import "../../ERC20/IWETH.sol";
import "./CollateralPoolLibrary.sol";

contract CollateralPool is ReentrancyGuard {
    /* ========== STATE VARIABLES ========== */

    address public WETH;
    address public smartcontract_owner;
    address public xsd_contract_address;
    address public bankx_contract_address;
    address public xsdweth_pool;
    address public bankxweth_pool;
    address public pid_address;
    BankXToken private BankX;
    XSDStablecoin private XSD;
    IPIDController private pid_controller;
    uint256 public collat_XSD;
    bool public mint_paused;
    bool public redeem_paused;
    bool public buyback_paused;
    struct MintInfo {
        uint256 accum_interest; //accumulated interest from previous mints
        uint256 interest_rate; //interest rate at that particular timestamp
        uint256 time; //last timestamp
        uint256 amount; //XSD amount minted
    }
    mapping(address=>MintInfo) public mintMapping; 
    mapping (address => uint256) public redeemBankXBalances;
    mapping (address => uint256) public redeemCollateralBalances;
    mapping (address => uint256) public vestingtimestamp;
    uint256 public unclaimedPoolCollateral;
    uint256 public unclaimedPoolBankX;
    uint256 public collateral_equivalent_d18;
    uint256 public bankx_minted_count;
    mapping (address => uint256) public lastRedeemed;
    uint256 public block_delay = 2;
    /* ========== MODIFIERS ========== */
    modifier ensure(uint deadline) {
        require(deadline >= block.timestamp, 'BankXRouter: EXPIRED');
        _;
    }

    modifier onlyByOwner() {
        require(msg.sender == smartcontract_owner, "Not owner");
        _;
    }
 
    /* ========== CONSTRUCTOR ========== */

    constructor(
        address _xsd_contract_address,
        address _bankx_contract_address,
        address _bankxweth_pool,
        address _xsdweth_pool,
        address _WETH,
        address _smartcontract_owner
    ) {
        require(
            (_xsd_contract_address != address(0))
            && (_bankx_contract_address != address(0))
            && (_WETH != address(0))
            && (_bankxweth_pool != address(0))
            && (_xsdweth_pool != address(0))
        , "Zero address detected"); 
        XSD = XSDStablecoin(_xsd_contract_address);
        BankX = BankXToken(_bankx_contract_address);
        xsd_contract_address = _xsd_contract_address;
        bankx_contract_address = _bankx_contract_address;
        xsdweth_pool = _xsdweth_pool;
        bankxweth_pool = _bankxweth_pool;
        WETH = _WETH;
        smartcontract_owner = _smartcontract_owner;
    }

    /* ========== VIEWS ========== */

    //only accept ETH via fallback function from the WETH contract
    receive() external payable {
        assert(msg.sender == WETH);
    }

    // Returns dollar value of collateral held in this XSD pool
    function collatDollarBalance() public view returns (uint256) {
            return ((IWETH(WETH).balanceOf(address(this))*XSD.eth_usd_price())/(1e6));        
    }

    // Returns the value of excess collateral held in this XSD pool, compared to what is needed to maintain the global collateral ratio
    function availableExcessCollatDV() public view returns (uint256) {
        uint256 global_collateral_ratio = XSD.global_collateral_ratio();
        uint256 global_collat_value = XSD.globalCollateralValue();

        if (global_collateral_ratio > (1e6)) global_collateral_ratio = (1e6); // Handles an overcollateralized contract with CR > 1
        uint256 required_collat_dollar_value_d18 = ((collat_XSD)*global_collateral_ratio*(XSD.xag_usd_price()*(1e4))/(311035))/(1e12); // Calculates collateral needed to back each 1 XSD with $1 of collateral at current collat ratio
        if ((global_collat_value-unclaimedPoolCollateral)>required_collat_dollar_value_d18) return (global_collat_value-unclaimedPoolCollateral-required_collat_dollar_value_d18);
        else return 0;
    }
    /* ========== INTERNAL FUNCTIONS ======== */
    //call the price check function again after check.

    function mintInterestCalc(uint xsd_amount,address sender) internal {
        (mintMapping[sender].accum_interest, mintMapping[sender].interest_rate, mintMapping[sender].time, mintMapping[sender].amount) = CollateralPoolLibrary.calcMintInterest(xsd_amount,XSD.xag_usd_price(), XSD.interest_rate(), mintMapping[sender].accum_interest, mintMapping[sender].interest_rate, mintMapping[sender].time, mintMapping[sender].amount);
    }
    function redeemInterestCalc(uint xsd_amount,address sender) internal {
        (mintMapping[sender].accum_interest, mintMapping[sender].interest_rate, mintMapping[sender].time, mintMapping[sender].amount)=CollateralPoolLibrary.calcRedemptionInterest(xsd_amount,XSD.xag_usd_price(), mintMapping[sender].accum_interest, mintMapping[sender].interest_rate, mintMapping[sender].time, mintMapping[sender].amount);
    }

    /* ========== PUBLIC FUNCTIONS ========== */
    
    // We separate out the 1t1, fractional and algorithmic minting functions for gas efficiency 
    function mint1t1XSD(uint256 XSD_out_min, uint256 deadline) external ensure(deadline) payable nonReentrant {
        require(!mint_paused, "Mint Paused");
        require(msg.value>0, "Invalid collateral amount");
        require(XSD.global_collateral_ratio() >= (1e6), "Collateral ratio must be >= 1");
        (uint256 xsd_amount_d18) = CollateralPoolLibrary.calcMint1t1XSD(
            XSD.eth_usd_price(),
            XSD.xag_usd_price(),
            msg.value
        ); //1 XSD for each $1 worth of collateral
        require(XSD_out_min <= xsd_amount_d18, "Slippage limit reached");
        mintInterestCalc(xsd_amount_d18,msg.sender);
        IWETH(WETH).deposit{value: msg.value}();
        assert(IWETH(WETH).transfer(address(this), msg.value));
        collat_XSD = collat_XSD + xsd_amount_d18;
        XSD.pool_mint(msg.sender, xsd_amount_d18);
    }

    // 0% collateral-backed
    function mintAlgorithmicXSD(uint256 bankx_amount_d18, uint256 XSD_out_min, uint256 deadline) external ensure(deadline) nonReentrant {
        require(!mint_paused, "Mint Paused");
        require(((pid_controller.lastPriceCheck(msg.sender).lastpricecheck+(block_delay)) <= block.number) && (pid_controller.lastPriceCheck(msg.sender).pricecheck), "Must wait for block_delay blocks before minting");
        uint256 xag_usd_price = XSD.xag_usd_price();
        require(XSD.global_collateral_ratio() == 0, "Collateral ratio must be 0");
        (uint256 xsd_amount_d18) = CollateralPoolLibrary.calcMintAlgorithmicXSD(
            pid_controller.bankx_updated_price(), 
            xag_usd_price,
            bankx_amount_d18
        );
        require(XSD_out_min <= xsd_amount_d18, "Slippage limit reached");
        mintInterestCalc(xsd_amount_d18,msg.sender);
        collat_XSD = collat_XSD + xsd_amount_d18;
        bankx_minted_count = bankx_minted_count + bankx_amount_d18;
        pid_controller.lastPriceCheck(msg.sender).pricecheck = false;
        BankX.pool_burn_from(msg.sender, bankx_amount_d18);
        XSD.pool_mint(msg.sender, xsd_amount_d18);
    }

    // Will fail if fully collateralized or fully algorithmic
    // > 0% and < 100% collateral-backed
    function mintFractionalXSD(uint256 bankx_amount, uint256 XSD_out_min, uint256 deadline) external ensure(deadline) payable nonReentrant {
        require(!mint_paused, "Mint Paused");
        require(((pid_controller.lastPriceCheck(msg.sender).lastpricecheck+(block_delay)) <= block.number) && (pid_controller.lastPriceCheck(msg.sender).pricecheck), "Must wait for block_delay blocks before minting");
        uint256 xag_usd_price = XSD.xag_usd_price();
        uint256 global_collateral_ratio = XSD.global_collateral_ratio();

        require(global_collateral_ratio < (1e6) && global_collateral_ratio > 0, "Collateral ratio needs to be between .000001 and .999999");
        CollateralPoolLibrary.MintFF_Params memory input_params = CollateralPoolLibrary.MintFF_Params(
            pid_controller.bankx_updated_price(), //XSD.bankx_price
            XSD.eth_usd_price(),
            bankx_amount,
            msg.value,
            global_collateral_ratio
        );

        (uint256 mint_amount, uint256 bankx_needed) = CollateralPoolLibrary.calcMintFractionalXSD(input_params);
        mint_amount = (mint_amount*31103477)/((xag_usd_price)); //grams of silver in calculated mint amount
        require(XSD_out_min <= mint_amount, "Slippage limit reached");
        require(bankx_needed <= bankx_amount, "Not enough BankX inputted");
        mintInterestCalc(mint_amount,msg.sender);
        bankx_minted_count = bankx_minted_count + bankx_needed;
        BankX.pool_burn_from(msg.sender, bankx_needed);
        IWETH(WETH).deposit{value: msg.value}();
        assert(IWETH(WETH).transfer(address(this), msg.value));
        collat_XSD = collat_XSD + mint_amount;
        pid_controller.lastPriceCheck(msg.sender).pricecheck = false;
        XSD.pool_mint(msg.sender, mint_amount);
    }

    // Redeem collateral. 100% collateral-backed
    function redeem1t1XSD(uint256 XSD_amount, uint256 COLLATERAL_out_min, uint256 deadline) external ensure(deadline) nonReentrant {
        require(!pid_controller.bucket3(), "Cannot withdraw in times of deficit");
        require(!redeem_paused, "Redeem Paused");
        require(XSD.global_collateral_ratio() == (1e6), "Collateral ratio must be == 1");
        require(XSD_amount<=mintMapping[msg.sender].amount, "OVERREDEMPTION ERROR");
        require(((pid_controller.lastPriceCheck(msg.sender).lastpricecheck+(block_delay)) <= block.number) && (pid_controller.lastPriceCheck(msg.sender).pricecheck), "Must wait for block_delay blocks before redeeming");
        // convert xsd to $ and then to collateral value
        (uint256 XSD_dollar,uint256 collateral_needed) = CollateralPoolLibrary.calcRedeem1t1XSD(
            XSD.eth_usd_price(),
            XSD.xag_usd_price(),
            XSD_amount
        );
        uint total_xsd_amount = mintMapping[msg.sender].amount;
        require(collateral_needed <= (IWETH(WETH).balanceOf(address(this))-unclaimedPoolCollateral), "Not enough collateral in pool");
        require(COLLATERAL_out_min <= collateral_needed, "Slippage limit reached");
        redeemInterestCalc(XSD_amount, msg.sender);
        uint current_accum_interest = (XSD_amount*mintMapping[msg.sender].accum_interest)/total_xsd_amount;
        redeemBankXBalances[msg.sender] = (redeemBankXBalances[msg.sender]+current_accum_interest);
        redeemCollateralBalances[msg.sender] = redeemCollateralBalances[msg.sender]+XSD_dollar;
        unclaimedPoolCollateral = unclaimedPoolCollateral+XSD_dollar;
        lastRedeemed[msg.sender] = block.number;
        unclaimedPoolBankX = (unclaimedPoolBankX+current_accum_interest);
        uint256 bankx_amount = (current_accum_interest*1e6)/pid_controller.bankx_updated_price();
        collat_XSD -= XSD_amount;
        mintMapping[msg.sender].accum_interest = (mintMapping[msg.sender].accum_interest - current_accum_interest);
        pid_controller.lastPriceCheck(msg.sender).pricecheck = false;
        XSD.pool_burn_from(msg.sender, XSD_amount);
        BankX.pool_mint(address(this), bankx_amount);
    }

    // Will fail if fully collateralized or algorithmic
    // Redeem XSD for collateral and BankX. > 0% and < 100% collateral-backed
    function redeemFractionalXSD(uint256 XSD_amount, uint256 BankX_out_min, uint256 COLLATERAL_out_min, uint256 deadline) external ensure(deadline) nonReentrant {
        require(!pid_controller.bucket3(), "Cannot withdraw in times of deficit");
        require(((pid_controller.lastPriceCheck(msg.sender).lastpricecheck+(block_delay)) <= block.number) && (pid_controller.lastPriceCheck(msg.sender).pricecheck), "Must wait for block_delay blocks before redeeming");
        require(!redeem_paused, "Redeem Paused");
        require(XSD_amount<=mintMapping[msg.sender].amount, "OVERREDEMPTION ERROR");
        uint256 xag_usd_price = XSD.xag_usd_price();
        uint256 global_collateral_ratio = XSD.global_collateral_ratio();

        require(global_collateral_ratio < (1e6) && global_collateral_ratio > 0, "Collateral ratio needs to be between .000001 and .999999");
        

        uint256 bankx_dollar_value_d18 = XSD_amount - ((XSD_amount*global_collateral_ratio)/(1e6));
        bankx_dollar_value_d18 = (bankx_dollar_value_d18*xag_usd_price)/(31103477);
        uint256 bankx_amount = (bankx_dollar_value_d18*1e6)/pid_controller.bankx_updated_price();


        uint256 collateral_dollar_value = (XSD_amount*global_collateral_ratio)/(1e6);
        collateral_dollar_value = (collateral_dollar_value*xag_usd_price)/31103477;
        uint256 collateral_amount = (collateral_dollar_value*1e6)/XSD.eth_usd_price();


        require(collateral_amount <= (IWETH(WETH).balanceOf(address(this))-unclaimedPoolCollateral), "Not enough collateral in pool");
        require(COLLATERAL_out_min <= collateral_amount, "Slippage limit reached [collateral]");
        require(BankX_out_min <= bankx_amount, "Slippage limit reached [BankX]");

        redeemCollateralBalances[msg.sender] = redeemCollateralBalances[msg.sender]+collateral_dollar_value;
        unclaimedPoolCollateral = unclaimedPoolCollateral+collateral_dollar_value;
        lastRedeemed[msg.sender] = block.number;
        uint total_xsd_amount = mintMapping[msg.sender].amount;
        redeemInterestCalc(XSD_amount, msg.sender);
        uint current_accum_interest = (XSD_amount*mintMapping[msg.sender].accum_interest)/total_xsd_amount;
        redeemBankXBalances[msg.sender] = redeemBankXBalances[msg.sender]+current_accum_interest;
        bankx_amount = bankx_amount + ((current_accum_interest*1e6)/pid_controller.bankx_updated_price());
        mintMapping[msg.sender].accum_interest = mintMapping[msg.sender].accum_interest - current_accum_interest;
        redeemBankXBalances[msg.sender] = redeemBankXBalances[msg.sender]+bankx_dollar_value_d18;
        unclaimedPoolBankX = unclaimedPoolBankX+bankx_dollar_value_d18+current_accum_interest;
        collat_XSD -= XSD_amount;
        pid_controller.lastPriceCheck(msg.sender).pricecheck = false;
    
        XSD.pool_burn_from(msg.sender, XSD_amount);
        BankX.pool_mint(address(this), bankx_amount);
    }

    // Redeem XSD for BankX. 0% collateral-backed
    function redeemAlgorithmicXSD(uint256 XSD_amount, uint256 BankX_out_min, uint256 deadline) external ensure(deadline) nonReentrant {
        require(!pid_controller.bucket3(), "Cannot withdraw in times of deficit");
        require(!redeem_paused, "Redeem Paused");
        require(XSD_amount<=mintMapping[msg.sender].amount, "OVERREDEMPTION ERROR");
        require(((pid_controller.lastPriceCheck(msg.sender).lastpricecheck+(block_delay)) <= block.number) && (pid_controller.lastPriceCheck(msg.sender).pricecheck), "Must wait for block_delay blocks before redeeming");
        require(XSD.global_collateral_ratio() == 0, "Collateral ratio must be 0"); 
        uint256 bankx_dollar_value_d18 = (XSD_amount*XSD.xag_usd_price())/(31103477);

        uint256 bankx_amount = (bankx_dollar_value_d18*1e6)/pid_controller.bankx_updated_price();
        
        lastRedeemed[msg.sender] = block.number;
        uint total_xsd_amount = mintMapping[msg.sender].amount;
        require(BankX_out_min <= bankx_amount, "Slippage limit reached");
        redeemInterestCalc(XSD_amount, msg.sender);
        uint current_accum_interest = XSD_amount*mintMapping[msg.sender].accum_interest/total_xsd_amount; //precision of 6
        redeemBankXBalances[msg.sender] = (redeemBankXBalances[msg.sender]+current_accum_interest);
        bankx_amount = bankx_amount + ((current_accum_interest*1e6)/pid_controller.bankx_updated_price());
        mintMapping[msg.sender].accum_interest = (mintMapping[msg.sender].accum_interest - current_accum_interest);
        redeemBankXBalances[msg.sender] = redeemBankXBalances[msg.sender]+bankx_dollar_value_d18;
        unclaimedPoolBankX = unclaimedPoolBankX+bankx_dollar_value_d18+current_accum_interest;
        collat_XSD -= XSD_amount;
        pid_controller.lastPriceCheck(msg.sender).pricecheck = false;
        XSD.pool_burn_from(msg.sender, XSD_amount);
        BankX.pool_mint(address(this), bankx_amount);
    }

    // After a redemption happens, transfer the newly minted BankX and owed collateral from this pool
    // contract to the user. Redemption is split into two functions to prevent flash loans from being able
    // to take out XSD/collateral from the system, use an AMM to trade the new price, and then mint back into the system.
    function collectRedemption() external nonReentrant{
        require(!pid_controller.bucket3(), "Cannot withdraw in times of deficit");
        require(!redeem_paused, "Redeem Paused");
        require(((lastRedeemed[msg.sender]+(block_delay)) <= block.number) && ((pid_controller.lastPriceCheck(msg.sender).lastpricecheck+(block_delay)) <= block.number) && (pid_controller.lastPriceCheck(msg.sender).pricecheck), "Must wait for block_delay blocks before redeeming");
        uint BankXDollarAmount;
        uint CollateralDollarAmount;
        uint BankXAmount;
        uint CollateralAmount;

        // Use Checks-Effects-Interactions pattern
        if(redeemBankXBalances[msg.sender] > 0){
            BankXDollarAmount = redeemBankXBalances[msg.sender];
            BankXAmount = (BankXDollarAmount*1e6)/pid_controller.bankx_updated_price();
            redeemBankXBalances[msg.sender] = 0;
            unclaimedPoolBankX = unclaimedPoolBankX-BankXDollarAmount;
            TransferHelper.safeTransfer(address(BankX), msg.sender, BankXAmount);
        }
        
        if(redeemCollateralBalances[msg.sender] > 0){
            CollateralDollarAmount = redeemCollateralBalances[msg.sender];
            CollateralAmount = (CollateralDollarAmount*1e6)/XSD.eth_usd_price();
            redeemCollateralBalances[msg.sender] = 0;
            unclaimedPoolCollateral = unclaimedPoolCollateral-CollateralDollarAmount;
            IWETH(WETH).withdraw(CollateralAmount); //try to unwrap eth in the redeem
            TransferHelper.safeTransferETH(msg.sender, CollateralAmount);
        }
        pid_controller.lastPriceCheck(msg.sender).pricecheck = false;
    }

    // Function can be called by an BankX holder to have the protocol buy back BankX with excess collateral value from a desired collateral pool
    // This can also happen if the collateral ratio > 1
    // add XSD as a burn option while uXSD value is positive
    // need two seperate functions: one for bankx and one for XSD
    function buyBackBankX(uint256 BankX_amount,uint256 COLLATERAL_out_min, uint256 deadline) external ensure(deadline){
        require(!buyback_paused, "Buyback Paused");
        require(((pid_controller.lastPriceCheck(msg.sender).lastpricecheck+(block_delay)) <= block.number) && (pid_controller.lastPriceCheck(msg.sender).pricecheck), "Must wait for block_delay blocks before buyback");
        CollateralPoolLibrary.BuybackBankX_Params memory input_params = CollateralPoolLibrary.BuybackBankX_Params(
            availableExcessCollatDV(),
            pid_controller.bankx_updated_price(),
            XSD.eth_usd_price(),
            BankX_amount
        );

        (collateral_equivalent_d18) = (CollateralPoolLibrary.calcBuyBackBankX(input_params));

        require(COLLATERAL_out_min <= collateral_equivalent_d18, "Slippage limit reached");
        pid_controller.lastPriceCheck(msg.sender).pricecheck = false;
        // Give the sender their desired collateral and burn the BankX
        BankX.pool_burn_from(msg.sender, BankX_amount);
        TransferHelper.safeTransfer(address(WETH), address(this), collateral_equivalent_d18);
        IWETH(WETH).withdraw(collateral_equivalent_d18);
        TransferHelper.safeTransferETH(msg.sender, collateral_equivalent_d18);
    }
    //buyback with XSD instead of bankx
    function buyBackXSD(uint256 XSD_amount, uint256 collateral_out_min, uint256 deadline) external ensure(deadline){
        require(!buyback_paused, "Buyback Paused");
        require(((pid_controller.lastPriceCheck(msg.sender).lastpricecheck+(block_delay)) <= block.number) && (pid_controller.lastPriceCheck(msg.sender).pricecheck), "Must wait for block_delay blocks before buyback");
        if(XSD_amount != 0) require((XSD.totalSupply()+XSD_amount)>collat_XSD, "uXSD MUST BE POSITIVE");

        CollateralPoolLibrary.BuybackXSD_Params memory input_params = CollateralPoolLibrary.BuybackXSD_Params(
            availableExcessCollatDV(),
            pid_controller.xsd_updated_price(),
            XSD.eth_usd_price(),
            XSD_amount
        );

        (collateral_equivalent_d18) = (CollateralPoolLibrary.calcBuyBackXSD(input_params));

        require(collateral_out_min <= collateral_equivalent_d18, "Slippage limit reached");
        pid_controller.lastPriceCheck(msg.sender).pricecheck = false;
        XSD.pool_burn_from(msg.sender, XSD_amount);
        TransferHelper.safeTransfer(address(WETH), address(this), collateral_equivalent_d18);
        IWETH(WETH).withdraw(collateral_equivalent_d18);
        TransferHelper.safeTransferETH(msg.sender, collateral_equivalent_d18);
    }

    // Combined into one function due to 24KiB contract memory limit
    function setPoolParameters(uint256 new_block_delay, bool _mint_paused, bool _redeem_paused, bool _buyback_paused) external onlyByOwner {
        block_delay = new_block_delay;
        mint_paused = _mint_paused;
        redeem_paused = _redeem_paused;
        buyback_paused = _buyback_paused;
        emit PoolParametersSet(new_block_delay);
    }

    function setPIDController(address new_pid_address) external onlyByOwner {
        pid_controller = IPIDController(new_pid_address);
        pid_address = new_pid_address;
    }
    function setSmartContractOwner(address _smartcontract_owner) external{
        require(msg.sender == smartcontract_owner, "Only the smart contract owner can access this function");
        require(_smartcontract_owner != address(0), "Zero address detected");
        smartcontract_owner = _smartcontract_owner;
    }

    function renounceOwnership() external{
        require(msg.sender == smartcontract_owner, "Only the smart contract owner can access this function");
        smartcontract_owner = address(0);
    }

    function resetAddresses(address _xsd_contract_address,
        address _bankx_contract_address,
        address _bankxweth_pool,
        address _xsdweth_pool,
        address _WETH) external{
        require(msg.sender == smartcontract_owner, "Only the smart contract owner can access this function");
        require(
            (_xsd_contract_address != address(0))
            && (_bankx_contract_address != address(0))
            && (_WETH != address(0))
            && (_bankxweth_pool != address(0))
            && (_xsdweth_pool != address(0))
        , "Zero address detected"); 
        XSD = XSDStablecoin(_xsd_contract_address);
        BankX = BankXToken(_bankx_contract_address);
        xsd_contract_address = _xsd_contract_address;
        bankx_contract_address = _bankx_contract_address;
        xsdweth_pool = _xsdweth_pool;
        bankxweth_pool = _bankxweth_pool;
        WETH = _WETH;
    }

    /* ========== EVENTS ========== */

    event PoolParametersSet(uint256 new_block_delay);

}
// File: contracts/XSD/Pools/Interfaces/IXSDWETHpool.sol



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

interface IXSDWETHpool {
    function PERMIT_TYPEHASH() external pure returns (bytes32);
    function nonces(address owner) external view returns (uint);
    function getReserves() external view returns (uint112 reserve0, uint112 reserve1, uint32 blockTimestampLast);
    function price0CumulativeLast() external view returns (uint);
    function price1CumulativeLast() external view returns (uint);
    function kLast() external view returns (uint);
    function collatDollarBalance() external returns (uint);
    function swap(uint amount0Out, uint amount1Out, address to) external;
    function skim(address to) external;
    function sync() external;
}
// File: contracts/XSD/Pools/Interfaces/IBankXWETHpool.sol



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

interface IBankXWETHpool {
    function PERMIT_TYPEHASH() external pure returns (bytes32);
    function nonces(address owner) external view returns (uint);
    function getReserves() external view returns (uint112 reserve0, uint112 reserve1, uint32 blockTimestampLast);
    function price0CumulativeLast() external view returns (uint);
    function price1CumulativeLast() external view returns (uint);
    function kLast() external view returns (uint);
    function collatDollarBalance() external returns(uint);
    function swap(uint amount0Out, uint amount1Out, address to) external;
    function skim(address to) external;
    function sync() external;
}
// File: contracts/XSD/XSDStablecoin.sol



// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity ^0.8.0;


import "@openzeppelin/contracts/utils/Context.sol";
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "../ERC20/ERC20Custom.sol";
import "@openzeppelin/contracts/token/ERC20/ERC20.sol";
import "./Pools/CollateralPool.sol";
import "./Pools/Interfaces/IBankXWETHpool.sol";
import "./Pools/Interfaces/IXSDWETHpool.sol";
import "../Oracle/ChainlinkETHUSDPriceConsumer.sol";
import "../Oracle/ChainlinkXAGUSDPriceConsumer.sol";

contract XSDStablecoin is ERC20Custom {

    /* ========== STATE VARIABLES ========== */
    enum PriceChoice { XSD, BankX }
    ChainlinkETHUSDPriceConsumer private eth_usd_pricer;
    ChainlinkXAGUSDPriceConsumer private xag_usd_pricer;
    uint8 private eth_usd_pricer_decimals;
    uint8 private xag_usd_pricer_decimals;
    string public symbol;
    string public name;
    uint8 public constant decimals = 18;
    address public pid_address;
    address public treasury; 
    address public collateral_pool_address;
    address public router;
    address public eth_usd_oracle_address;
    address public xag_usd_oracle_address;
    address public smartcontract_owner;
    uint256 public interest_rate;
    IBankXWETHpool private bankxEthPool;
    IXSDWETHpool private xsdEthPool;
    uint256 public cap_rate;
    uint256 public genesis_supply; 
    //test variables
    uint256 ethusdprice;
    uint256 xagusdprice;

    // The addresses in this array are added by the oracle and these contracts are able to mint xsd
    address[] public xsd_pools_array;

    // Mapping is also used for faster verification
    mapping(address => bool) public xsd_pools; 

    // Constants for various precisions
    uint256 private constant PRICE_PRECISION = 1e6;
    
    uint256 public global_collateral_ratio; // 6 decimals of precision, e.g. 924102 = 0.924102
    uint256 public xsd_step; // Amount to change the collateralization ratio by upon refreshCollateralRatio()
    uint256 public refresh_cooldown; // Seconds to wait before being able to run refreshCollateralRatio() again
    uint256 public price_target; // The price of XSD at which the collateral ratio will respond to; this value is only used for the collateral ratio mechanism and not for minting and redeeming which are hardcoded at $1
    uint256 public price_band; // The bound above and below the price target at which the refreshCollateralRatio() will not change the collateral ratio

    bool public collateral_ratio_paused = false;

    /* ========== MODIFIERS ========== */

    modifier onlyPools() {
       require(xsd_pools[msg.sender] == true, "Only xsd pools can call this function");
        _;//check happens before the function is executed 
    } 

    modifier onlyByOwner(){
        require(msg.sender == smartcontract_owner, "You are not the owner");
        _;
    }
    
    modifier onlyByOwnerPID() {
        require(msg.sender == smartcontract_owner || msg.sender == pid_address, "You are not the owner or the pid controller");
        _;
    }

    modifier onlyByOwnerOrPool() {
        require(
            msg.sender == smartcontract_owner  
            || xsd_pools[msg.sender] == true, 
            "You are not the owner or a pool");
        _;
    }

    /* ========== CONSTRUCTOR ========== */

    constructor(
        string memory _name,
        string memory _symbol,
        uint256 _pool_amount,
        uint256 _genesis_supply,
        address _smartcontract_owner,
        address _treasury,
        uint256 _cap_rate
    ) {
        require((_smartcontract_owner != address(0))
                && (_treasury != address(0)), "Zero address detected"); 
        name = _name;
        symbol = _symbol;
        genesis_supply = _genesis_supply + _pool_amount;
        treasury = _treasury;
        _mint(_smartcontract_owner, _pool_amount);
        _mint(treasury, _genesis_supply);
        smartcontract_owner = _smartcontract_owner;
        xsd_step = 2500; // 6 decimals of precision, equal to 0.25%
        global_collateral_ratio = 1000000; // XSD system starts off fully collateralized (6 decimals of precision)
        interest_rate = 52800; //interest rate starts off at 5%
        refresh_cooldown = 3600; // Refresh cooldown period is set to 1 hour (3600 seconds) at genesis
        price_target = 800000; // Change price target to 1 gram of silver
        price_band = 5000; // Collateral ratio will not adjust if 0.005 off target at genesis
        cap_rate = _cap_rate;// Maximum mint amount
    }
    /* ========== VIEWS ========== */

    function pool_price(PriceChoice choice) internal view returns (uint256) {
        // Get the ETH / USD price first, and cut it down to 1e6 precision
        uint256 _eth_usd_price = 1200000000;//(uint256(eth_usd_pricer.getLatestPrice())*PRICE_PRECISION)/(uint256(10) ** eth_usd_pricer_decimals);
        uint256 price_vs_eth = 0;
        uint256 reserve0;
        uint256 reserve1;

        if (choice == PriceChoice.XSD) {
            (reserve0, reserve1, ) = xsdEthPool.getReserves();
            if(reserve0 == 0 || reserve1 == 0){
                return 1;
            }
            price_vs_eth = reserve0/(reserve1); // How much XSD if you put in 1 WETH
        }
        else if (choice == PriceChoice.BankX) {
            (reserve0, reserve1, ) = bankxEthPool.getReserves();
            if(reserve0 == 0 || reserve1 == 0){
                return 1;
            }
            price_vs_eth = reserve0/(reserve1);  // How much BankX if you put in 1 WETH
        }
        else revert("INVALID PRICE CHOICE. Needs to be either 0 (XSD) or 1 (BankX)");

        // Will be in 1e6 format
        return _eth_usd_price/price_vs_eth;
    }

    
    //XSD price
    function xsd_price() public view returns (uint256) {
        return pool_price(PriceChoice.XSD);
    }

    function bankx_price()  public view returns (uint256) {
        return pool_price(PriceChoice.BankX);
    }

    function eth_usd_price() public view returns (uint256) {
        return ethusdprice;//(uint256(eth_usd_pricer.getLatestPrice())*PRICE_PRECISION)/(uint256(10) ** eth_usd_pricer_decimals);
    }
    //silver price
    //hard coded value for testing on goerli
    function xag_usd_price() public view returns (uint256) {
        return xagusdprice;//(uint256(xag_usd_pricer.getLatestPrice())*PRICE_PRECISION)/(uint256(10) ** xag_usd_pricer_decimals);
    }
    //test functions
    function setETHUSDPRICE(uint _eth_usd_price) public {
        ethusdprice = _eth_usd_price;
    }
    function setXAGUSDPRICE(uint _xag_usd_price) public {
        xagusdprice = _xag_usd_price;
    }

    
    // This is needed to avoid costly repeat calls to different getter functions
    // It is cheaper gas-wise to just dump everything and only use some of the info
    function xsd_info() public view returns (uint256, uint256, uint256, uint256, uint256, uint256) {
        return (
            pool_price(PriceChoice.XSD), // xsd_price()
            pool_price(PriceChoice.BankX), // bankx_price()
            totalSupply(), // totalSupply()
            global_collateral_ratio, // global_collateral_ratio()
            globalCollateralValue(), // globalCollateralValue
            (uint256(eth_usd_pricer.getLatestPrice())*PRICE_PRECISION)/(uint256(10) ** eth_usd_pricer_decimals) //eth_usd_price
        );
    }

    // Iterate through all xsd pools and calculate all value of collateral in all pools globally 
    function globalCollateralValue() public view returns (uint256) {
        uint256 collateral_amount = 0;
        collateral_amount = CollateralPool(payable(collateral_pool_address)).collatDollarBalance();
        return collateral_amount;
    }

    /* ========== PUBLIC FUNCTIONS ========== */
    
    // There needs to be a time interval that this can be called. Otherwise it can be called multiple times per expansion.
    // To simulate global collateral ratio set xsd price higher than silver price and hit refresh collateral ratio.
    uint256 public last_call_time; // Last time the refreshCollateralRatio function was called
    function refreshCollateralRatio() public {
        require(collateral_ratio_paused == false, "Collateral Ratio has been paused");
        uint256 xsd_price_cur = xsd_price();
        require(block.timestamp - last_call_time >= refresh_cooldown, "Must wait for the refresh cooldown since last refresh");

        // Step increments are 0.25% (upon genesis, changable by setXSDStep()) 
        
        if (xsd_price_cur > (price_target+price_band)) { //decrease collateral ratio
            if(global_collateral_ratio <= xsd_step){ //if within a step of 0, go to 0
                global_collateral_ratio = 0;
            } else {
                global_collateral_ratio = global_collateral_ratio-xsd_step;
            }
        } else if (xsd_price_cur < price_target-price_band) { //increase collateral ratio
            if(global_collateral_ratio+xsd_step >= 1000000){
                global_collateral_ratio = 1000000; // cap collateral ratio at 1.000000
            } else {
                global_collateral_ratio = global_collateral_ratio+xsd_step;
            }
        }
        else
        last_call_time = block.timestamp; // Set the time of the last expansion
        uint256 _interest_rate = (1000000-global_collateral_ratio)/(2);
        //update interest rate
        if(_interest_rate>52800){
            interest_rate = _interest_rate;
        }
        else{
            interest_rate = 52800;
        }

        emit CollateralRatioRefreshed(global_collateral_ratio);
    }

    function creatorMint(uint256 amount) public onlyByOwner{
        require(genesis_supply+amount<cap_rate,"cap limit reached");
        super._mint(treasury,amount);
    }

    /* ========== RESTRICTED FUNCTIONS ========== */

    // Used by pools when user redeems
    function pool_burn_from(address b_address, uint256 b_amount) public onlyPools {
        super._burnFrom(b_address, b_amount);
        emit XSDBurned(b_address, msg.sender, b_amount);
    }

    // This function is what other xsd pools will call to mint new XSD 
    function pool_mint(address m_address, uint256 m_amount) public onlyPools {
        super._mint(m_address, m_amount);
        emit XSDMinted(msg.sender, m_address, m_amount);
    }
    

    // Adds collateral addresses supported, such as tether and busd, must be ERC20 
    function addPool(address pool_address) public onlyByOwner {
        require(pool_address != address(0), "Zero address detected");

        require(xsd_pools[pool_address] == false, "Address already exists");
        xsd_pools[pool_address] = true; 
        xsd_pools_array.push(pool_address);

        emit PoolAdded(pool_address);
    }

    // Remove a pool 
    function removePool(address pool_address) public onlyByOwner {
        require(pool_address != address(0), "Zero address detected");

        require(xsd_pools[pool_address] == true, "Address nonexistant");
        
        // Delete from the mapping
        delete xsd_pools[pool_address];

        // 'Delete' from the array by setting the address to 0x0
        for (uint i = 0; i < xsd_pools_array.length; i++){ 
            if (xsd_pools_array[i] == pool_address) {
                xsd_pools_array[i] = address(0); // This will leave a null in the array and keep the indices the same
                break;
            }
        }

        emit PoolRemoved(pool_address);
    }
// create a seperate function for users and the pool
    function burnpoolXSD(uint _xsdamount) public {
        require(msg.sender == router, "Only the router can access this function");
        require(totalSupply()-CollateralPool(payable(collateral_pool_address)).collat_XSD()>_xsdamount, "uXSD has to be positive");
        super._burn(address(xsdEthPool),_xsdamount);
        xsdEthPool.sync();
        emit XSDBurned(msg.sender, address(this), _xsdamount);
    }
    // add burn function for users
    function burnUserXSD(uint _xsdamount) public {
        require(totalSupply()-CollateralPool(payable(collateral_pool_address)).collat_XSD()>_xsdamount, "uXSD has to be positive");
        super._burn(msg.sender, _xsdamount);
        emit XSDBurned(msg.sender, address(this), _xsdamount);
    }
    function setXSDStep(uint256 _new_step) public onlyByOwnerPID {
        xsd_step = _new_step;

        emit XSDStepSet(_new_step);
    }  

    function setPriceTarget (uint256 _new_price_target) public onlyByOwnerPID {
        price_target = _new_price_target;

        emit PriceTargetSet(_new_price_target);
    }

    function setRefreshCooldown(uint256 _new_cooldown) public onlyByOwnerPID {
    	refresh_cooldown = _new_cooldown;

        emit RefreshCooldownSet(_new_cooldown);
    }

    function setTreasury(address _new_treasury) public onlyByOwner {
        require(_new_treasury != address(0), "Zero address detected");
        treasury = _new_treasury;
    }

    function setETHUSDOracle(address _eth_usd_oracle_address) public onlyByOwner {
        require(_eth_usd_oracle_address != address(0), "Zero address detected");

        eth_usd_oracle_address = _eth_usd_oracle_address;
        eth_usd_pricer = ChainlinkETHUSDPriceConsumer(eth_usd_oracle_address);
        eth_usd_pricer_decimals = eth_usd_pricer.getDecimals();

        emit ETHUSDOracleSet(_eth_usd_oracle_address);
    }
    
    function setXAGUSDOracle(address _xag_usd_oracle_address) public onlyByOwner {
        require(_xag_usd_oracle_address != address(0), "Zero address detected");

        xag_usd_oracle_address = _xag_usd_oracle_address;
        xag_usd_pricer = ChainlinkXAGUSDPriceConsumer(xag_usd_oracle_address);
        xag_usd_pricer_decimals = xag_usd_pricer.getDecimals();

        emit XAGUSDOracleSet(_xag_usd_oracle_address);
    }

    function setPIDController(address _pid_address) external onlyByOwner {
        require(_pid_address != address(0), "Zero address detected");

        pid_address = _pid_address;

        emit PIDControllerSet(_pid_address);
    }

    function setRouterAddress(address _router) external onlyByOwner {
        require(_router != address(0), "Zero address detected");
        router = _router;
    }

    function setPriceBand(uint256 _price_band) external onlyByOwner {
        price_band = _price_band;

        emit PriceBandSet(_price_band);
    }

    // Sets the XSD_ETH Uniswap oracle address 
    function setXSDEthPool(address _xsd_pool_addr) public onlyByOwner {
        require(_xsd_pool_addr != address(0), "Zero address detected");
        xsdEthPool = IXSDWETHpool(_xsd_pool_addr); 

        emit XSDETHPoolSet(_xsd_pool_addr);
    }

    // Sets the BankX_ETH Uniswap oracle address 
    function setBankXEthPool(address _bankx_pool_addr) public onlyByOwner {
        require(_bankx_pool_addr != address(0), "Zero address detected");
        bankxEthPool = IBankXWETHpool(_bankx_pool_addr);

        emit BankXEthPoolSet(_bankx_pool_addr);
    }

    //sets the collateral pool address
    function setCollateralEthPool(address _collateral_pool_address) public onlyByOwner {
        require(_collateral_pool_address != address(0), "Zero address detected");
        collateral_pool_address = payable(_collateral_pool_address);
    }

    function setSmartContractOwner(address _smartcontract_owner) external{
        require(msg.sender == smartcontract_owner, "Only the smart contract owner can access this function");
        require(_smartcontract_owner != address(0), "Zero address detected");
        smartcontract_owner = _smartcontract_owner;
    }

    function renounceOwnership() external{
        require(msg.sender == smartcontract_owner, "Only the smart contract owner can access this function");
        smartcontract_owner = address(0);
    }

    /* ========== EVENTS ========== */

    // Track XSD burned
    event XSDBurned(address indexed from, address indexed to, uint256 amount);

    // Track XSD minted
    event XSDMinted(address indexed from, address indexed to, uint256 amount);

    event CollateralRatioRefreshed(uint256 global_collateral_ratio);
    event PoolAdded(address pool_address);
    event PoolRemoved(address pool_address);
    event RedemptionFeeSet(uint256 red_fee);
    event MintingFeeSet(uint256 min_fee);
    event XSDStepSet(uint256 new_step);
    event PriceTargetSet(uint256 new_price_target);
    event RefreshCooldownSet(uint256 new_cooldown);
    event ETHUSDOracleSet(address eth_usd_oracle_address);
    event XAGUSDOracleSet(address xag_usd_oracle_address);
    event PIDControllerSet(address _pid_controller);
    event PriceBandSet(uint256 price_band);
    event XSDETHPoolSet(address xsd_pool_addr);
    event BankXEthPoolSet(address bankx_pool_addr);
    event CollateralRatioToggled(bool collateral_ratio_paused);
}
// File: contracts/UniswapFork/Interfaces/IRouter.sol



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


interface IRouter{
    function creatorAddLiquidityTokens(
        address tokenB,
        uint amountB,
        uint deadline
    ) external;

    function creatorAddLiquidityETH(
        address pool,
        uint deadline
    ) external payable;

    function userAddLiquidityETH(
        address pool,
        uint deadline
    ) external payable;

    function userRedeemLiquidity(
        address pool,
        uint deadline
    ) external;

    function swapETHForXSD(uint amountOut,uint deadline) external payable;

    function swapXSDForETH(uint amountOut, uint amountInMax, uint deadline) external;

    function swapETHForBankX(uint amountOut, uint deadline) external payable;
    
    function swapBankXForETH(uint amountOut, uint amountInMax, uint deadline) external;

    function swapBankXForXSD(uint bankx_amount, address sender, uint256 eth_min_amount, uint256 bankx_min_amount, uint256 deadline) external;

    function swapXSDForBankX(uint XSD_amount, address sender, uint256 eth_min_amount, uint256 xsd_min_amount, uint256 deadline) external;
}
// File: contracts/XSD/Pools/CollateralPoolLibrary.sol



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


library CollateralPoolLibrary {
    // ================ Structs ================
    // Needed to lower stack size
    struct MintFF_Params {
        uint256 bankx_price_usd; 
        uint256 col_price_usd;
        uint256 bankx_amount;
        uint256 collateral_amount;
        uint256 col_ratio;
    }

    struct BuybackBankX_Params {
        uint256 excess_collateral_dollar_value_d18;
        uint256 bankx_price_usd;
        uint256 col_price_usd;
        uint256 BankX_amount;
    }

    struct BuybackXSD_Params {
        uint256 excess_collateral_dollar_value_d18;
        uint256 xsd_price_usd;
        uint256 col_price_usd;
        uint256 XSD_amount;
    }



    // ================ Functions ================
// xsd is at the price of one gram of silver.
    function calcMint1t1XSD(uint256 col_price, uint256 silver_price, uint256 collateral_amount_d18) public pure returns (uint256) {
        uint256 gram_price = (silver_price*(1e4))/(311035);
        return (collateral_amount_d18*(col_price))/(gram_price); 
    }
// xsd is at the price of one gram of silver
    function calcMintAlgorithmicXSD(uint256 bankx_price_usd, uint256 silver_price, uint256 bankx_amount_d18) public pure returns (uint256) {
        uint256 gram_price = (silver_price*(1e4))/(311035);
        return (bankx_amount_d18*bankx_price_usd)/(gram_price);
    }

    function calcMintInterest(uint256 XSD_amount,uint256 silver_price,uint256 rate, uint256 accum_interest, uint256 interest_rate, uint256 time, uint256 amount) internal view returns(uint256, uint256, uint256, uint256) {
        uint256 gram_price = (silver_price*(1e4))/(311035);
        if(time == 0){
        interest_rate = rate;
        amount = XSD_amount;
        time = block.timestamp;
        }
        else{
        uint delta_t = block.timestamp - time;
        delta_t = delta_t/(86400); 
        accum_interest = accum_interest+((amount*gram_price*interest_rate*delta_t)/(365*(1e12)));
    
        interest_rate = (amount*interest_rate) + (XSD_amount*rate);
        amount = amount+XSD_amount;
        interest_rate = interest_rate/amount;
        time = block.timestamp;
        }
        return (
            accum_interest,
            interest_rate,
            time, 
            amount
        );
    }

    function calcRedemptionInterest(uint256 XSD_amount,uint256 silver_price, uint256 accum_interest, uint256 interest_rate, uint256 time, uint256 amount) internal view returns(uint256, uint256, uint256, uint256){
        uint256 gram_price = (silver_price*(1e4))/(311035);
        uint delta_t = block.timestamp - time;
        delta_t = delta_t/(86400);
        accum_interest = accum_interest+((amount*gram_price*interest_rate*delta_t)/(365*(1e12)));
        amount = amount - XSD_amount;
        time = block.timestamp;
        return (
            accum_interest,
            interest_rate,
            time, 
            amount
        );
    }
    
    // Must be internal because of the struct
    // xsd must be the dollar value of one price of silver
    function calcMintFractionalXSD(MintFF_Params memory params) internal pure returns (uint256, uint256) {
        // Since solidity truncates division, every division operation must be the last operation in the equation to ensure minimum error
        // The contract must check the proper ratio was sent to mint XSD. We do this by seeing the minimum mintable XSD based on each amount 
        uint256 bankx_dollar_value_d18;
        uint256 c_dollar_value_d18;
        
        // Scoping for stack concerns
        {    
            // USD amounts of the collateral and the BankX
            bankx_dollar_value_d18 = params.bankx_amount*(params.bankx_price_usd)/(1e6);
            c_dollar_value_d18 = params.collateral_amount*(params.col_price_usd)/(1e6);

        }
        uint calculated_bankx_dollar_value_d18 = 
                    (c_dollar_value_d18*(1e6)/(params.col_ratio))
                    -(c_dollar_value_d18);

        uint calculated_bankx_needed = calculated_bankx_dollar_value_d18*(1e6)/(params.bankx_price_usd);

        return (
            (c_dollar_value_d18+calculated_bankx_dollar_value_d18),
            calculated_bankx_needed
        );
    }

    function calcRedeem1t1XSD(uint256 col_price_usd,uint256 silver_price, uint256 XSD_amount) public pure returns (uint256,uint256) {
        uint256 gram_price = (silver_price*(1e4))/(311035);
        return ((XSD_amount*gram_price/1e6),((XSD_amount*gram_price)/col_price_usd));
    }

    // Must be internal because of the struct
    function calcBuyBackBankX(BuybackBankX_Params memory params) internal pure returns (uint256) {
        // If the total collateral value is higher than the amount required at the current collateral ratio then buy back up to the possible BankX with the desired collateral
        require(params.excess_collateral_dollar_value_d18 > 0, "No excess collateral to buy back!");

        // Make sure not to take more than is available
        uint256 bankx_dollar_value_d18 = (params.BankX_amount*params.bankx_price_usd);
        require((bankx_dollar_value_d18/1e6) <= params.excess_collateral_dollar_value_d18, "You are trying to buy back more than the excess!");

        // Get the equivalent amount of collateral based on the market value of BankX provided 
        uint256 collateral_equivalent_d18 = (bankx_dollar_value_d18)/(params.col_price_usd);
        //collateral_equivalent_d18 = collateral_equivalent_d18-((collateral_equivalent_d18*(params.buyback_fee))/(1e6));

        return (
            collateral_equivalent_d18
        );

    }

    function calcBuyBackXSD(BuybackXSD_Params memory params) internal pure returns (uint256) {
        require(params.excess_collateral_dollar_value_d18 > 0, "No excess collateral to buy back!");

        uint256 xsd_dollar_value_d18 = params.XSD_amount*(params.xsd_price_usd);
        require((xsd_dollar_value_d18/1e6) <= params.excess_collateral_dollar_value_d18, "You are trying to buy more than the excess!");

        uint256 collateral_equivalent_d18 = (xsd_dollar_value_d18)/(params.col_price_usd);

        return (
            collateral_equivalent_d18
        );
    }

}
// File: contracts/Oracle/Interfaces/IPIDController.sol



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

interface IPIDController{
    function bucket1() external view returns (bool);
    function bucket2() external view returns (bool);
    function bucket3() external view returns (bool);
    function diff1() external view returns (uint);
    function diff2() external view returns (uint);
    function diff3() external view returns (uint);
    function amountpaid1() external view returns (uint);
    function amountpaid2() external view returns (uint);
    function amountpaid3() external view returns (uint);
    function bankx_updated_price() external view returns (uint);
    function xsd_updated_price() external view returns (uint);
    function systemCalculations() external;
    struct PriceCheck{
        uint256 lastpricecheck;
        bool pricecheck;
    }
    function lastPriceCheck(address user) external view returns (PriceCheck memory info);
    function amountPaidBankXWETH(uint ethvalue) external;
    function amountPaidXSDWETH(uint ethvalue) external;
    function amountPaidCollateralPool(uint ethvalue) external;
}
// File: contracts/BankX/BankXToken.sol



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


import "../ERC20/ERC20Custom.sol";
import "@openzeppelin/contracts/utils/Context.sol";
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "../XSD/XSDStablecoin.sol";

contract BankXToken is ERC20Custom {

    /* ========== STATE VARIABLES ========== */

    string public symbol;
    string public name;
    uint8 public constant decimals = 18;
    
    
    uint256 public genesis_supply; // 2B is printed upon genesis
    address public pool_address; //points to BankX pool address
    address public treasury; //stores the genesis supply
    address public router;
    XSDStablecoin private XSD; //XSD stablecoin instance
    address public smartcontract_owner;
    /* ========== MODIFIERS ========== */

    modifier onlyPools() {
       require(XSD.xsd_pools(msg.sender) == true, "Only xsd pools can mint new BankX");
        _;
    } 
    
    modifier onlyByOwner() {
        require(msg.sender == smartcontract_owner, "You are not an owner");
        _;
    }

    /* ========== CONSTRUCTOR ========== */

    constructor(
        string memory _name,
        string memory _symbol,
        uint256 _pool_amount, 
        uint256 _genesis_supply,
        address _treasury,
        address _smartcontract_owner
    ) {
        require((_treasury != address(0)), "Zero address detected"); 
        name = _name;
        symbol = _symbol;
        genesis_supply = _genesis_supply + _pool_amount;
        treasury = _treasury;
        _mint(_msgSender(), _pool_amount);
        _mint(treasury, _genesis_supply);
        smartcontract_owner = _smartcontract_owner;

    
    }

    /* ========== RESTRICTED FUNCTIONS ========== */

    function setPool(address new_pool) external onlyByOwner {
        require(new_pool != address(0), "Zero address detected");

        pool_address = new_pool;
    }

    function setTreasury(address new_treasury) external onlyByOwner {
        require(new_treasury != address(0), "Treasury address cannot be 0");
        treasury = new_treasury;
    }

    function setRouterAddress(address _router) external onlyByOwner {
        require(_router != address(0), "Zero address detected");
        router = _router;
    }
    
    function setXSDAddress(address xsd_contract_address) external onlyByOwner {
        require(xsd_contract_address != address(0), "Zero address detected");

        XSD = XSDStablecoin(xsd_contract_address);

        emit XSDAddressSet(xsd_contract_address);
    }
    
    function mint(address to, uint256 amount) public onlyPools {
        _mint(to, amount);
        emit BankXMinted(address(this), to, amount);
    }
    
    function genesisSupply() public view returns(uint256){
        return genesis_supply;
    }

    // This function is what other xsd pools will call to mint new BankX (similar to the XSD mint) 
    function pool_mint(address m_address, uint256 m_amount) external onlyPools  {        
        super._mint(m_address, m_amount);
        emit BankXMinted(address(this), m_address, m_amount);
    }

    // This function is what other xsd pools will call to burn BankX 
    function pool_burn_from(address b_address, uint256 b_amount) external onlyPools {

        super._burnFrom(b_address, b_amount);
        emit BankXBurned(b_address, address(this), b_amount);
    }
    //burn bankx from the pool when bankx is inflationary
    function burnpoolBankX(uint _bankx_amount) public {
        require(msg.sender == router, "Only Router can access this function");
        require(totalSupply()>genesis_supply,"BankX must be deflationary");
        super._burn(pool_address, _bankx_amount);
        IBankXWETHpool(pool_address).sync();
        emit BankXBurned(msg.sender, address(this), _bankx_amount);
    }

    function setSmartContractOwner(address _smartcontract_owner) external{
        require(msg.sender == smartcontract_owner, "Only the smart contract owner can access this function");
        require(_smartcontract_owner != address(0), "Zero address detected");
        smartcontract_owner = _smartcontract_owner;
    }

    function renounceOwnership() external{
        require(msg.sender == smartcontract_owner, "Only the smart contract owner can access this function");
        smartcontract_owner = address(0);
    }
    /* ========== EVENTS ========== */

    // Track BankX burned
    event BankXBurned(address indexed from, address indexed to, uint256 amount);

    // Track BankX minted
    event BankXMinted(address indexed from, address indexed to, uint256 amount);
    event XSDAddressSet(address addr);
}
// File: @uniswap/lib/contracts/libraries/TransferHelper.sol



// SPDX-License-Identifier: GPL-3.0-or-later

pragma solidity >=0.6.0;

// helper methods for interacting with ERC20 tokens and sending ETH that do not consistently return true/false
library TransferHelper {
    function safeApprove(
        address token,
        address to,
        uint256 value
    ) internal {
        // bytes4(keccak256(bytes('approve(address,uint256)')));
        (bool success, bytes memory data) = token.call(abi.encodeWithSelector(0x095ea7b3, to, value));
        require(
            success && (data.length == 0 || abi.decode(data, (bool))),
            'TransferHelper::safeApprove: approve failed'
        );
    }

    function safeTransfer(
        address token,
        address to,
        uint256 value
    ) internal {
        // bytes4(keccak256(bytes('transfer(address,uint256)')));
        (bool success, bytes memory data) = token.call(abi.encodeWithSelector(0xa9059cbb, to, value));
        require(
            success && (data.length == 0 || abi.decode(data, (bool))),
            'TransferHelper::safeTransfer: transfer failed'
        );
    }

    function safeTransferFrom(
        address token,
        address from,
        address to,
        uint256 value
    ) internal {
        // bytes4(keccak256(bytes('transferFrom(address,address,uint256)')));
        (bool success, bytes memory data) = token.call(abi.encodeWithSelector(0x23b872dd, from, to, value));
        require(
            success && (data.length == 0 || abi.decode(data, (bool))),
            'TransferHelper::transferFrom: transferFrom failed'
        );
    }

    function safeTransferETH(address to, uint256 value) internal {
        (bool success, ) = to.call{value: value}(new bytes(0));
        require(success, 'TransferHelper::safeTransferETH: ETH transfer failed');
    }
}

// File: @openzeppelin/contracts/security/ReentrancyGuard.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (security/ReentrancyGuard.sol)

pragma solidity ^0.8.0;

/**
 * @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].
 */
abstract 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 making 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;
    }
}

// File: contracts/ERC20/IWETH.sol



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

interface IWETH {
    function deposit() external payable;
    function transfer(address to, uint value) external returns (bool);
    function transferFrom(address src, address dst, uint wad) external returns (bool);
    function balanceOf(address account) external view returns (uint256);
    function withdraw(uint) external;
}
// File: contracts/ERC20/ERC20Custom.sol



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

import "@openzeppelin/contracts/utils/Context.sol";
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/utils/math/SafeMath.sol";

// Due to compiling issues, _name, _symbol, and _decimals were removed


/**
 * @dev Implementation of the {IERC20} interface.
 *
 * This implementation is agnostic to the way tokens are created. This means
 * that a supply mechanism has to be added in a derived contract using {_mint}.
 * For a generic mechanism see {ERC20Mintable}.
 *
 * TIP: For a detailed writeup see our guide
 * https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How
 * to implement supply mechanisms].
 *
 * We have followed general OpenZeppelin guidelines: functions revert instead
 * of returning `false` on failure. This behavior is nonetheless conventional
 * and does not conflict with the expectations of ERC20 applications.
 *
 * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
 * This allows applications to reconstruct the allowance for all accounts just
 * by listening to said events. Other implementations of the EIP may not emit
 * these events, as it isn't required by the specification.
 *
 * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
 * functions have been added to mitigate the well-known issues around setting
 * allowances. See {IERC20-approve}.
 */
contract ERC20Custom is Context, IERC20 {
    using SafeMath for uint256;

    mapping (address => uint256) internal _balances;

    mapping (address => mapping (address => uint256)) internal _allowances;

    uint256 private _totalSupply;
    /**
     * @dev See {IERC20-totalSupply}.
     */
    function totalSupply() public view override returns (uint256) {
        return _totalSupply;
    }

    /**
     * @dev See {IERC20-balanceOf}.
     */
    function balanceOf(address account) public view override returns (uint256) {
        return _balances[account];
    }

    /**
     * @dev See {IERC20-transfer}.
     *
     * Requirements:
     *
     * - `recipient` cannot be the zero address.
     * - the caller must have a balance of at least `amount`.
     */
    function transfer(address to, uint256 amount) public virtual override returns (bool) {
        address owner = _msgSender();
        _transfer(owner, to, amount);
        return true;
    }

    /**
     * @dev See {IERC20-allowance}.
     */
    function allowance(address owner, address spender) public view virtual override returns (uint256) {
        return _allowances[owner][spender];
    }

    /**
     * @dev See {IERC20-approve}.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.approve(address spender, uint256 amount)
     */
    function approve(address spender, uint256 amount) public virtual override returns (bool) {
        address owner = _msgSender();
        _approve(owner, spender, amount);
        return true;
    }

    /**
     * @dev See {IERC20-transferFrom}.
     *
     * Emits an {Approval} event indicating the updated allowance. This is not
     * required by the EIP. See the note at the beginning of {ERC20}.
     *
     * NOTE: Does not update the allowance if the current allowance
     * is the maximum `uint256`.
     *
     * Requirements:
     *
     * - `from` and `to` cannot be the zero address.
     * - `from` must have a balance of at least `amount`.
     * - the caller must have allowance for ``from``'s tokens of at least
     * `amount`.
     */
    function transferFrom(
        address from,
        address to,
        uint256 amount
    ) public virtual override returns (bool) {
        address spender = _msgSender();
        _spendAllowance(from, spender, amount);
        _transfer(from, to, amount);
        return true;
    }

    /**
     * @dev Updates `owner` s allowance for `spender` based on spent `amount`.
     *
     * Does not update the allowance amount in case of infinite allowance.
     * Revert if not enough allowance is available.
     *
     * Might emit an {Approval} event.
     */
    function _spendAllowance(
        address owner,
        address spender,
        uint256 amount
    ) internal virtual {
        uint256 currentAllowance = allowance(owner, spender);
        if (currentAllowance != type(uint256).max) {
            require(currentAllowance >= amount, "ERC20: insufficient allowance");
            unchecked {
                _approve(owner, spender, currentAllowance - amount);
            }
        }
    }

    /**
     * @dev Atomically increases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
        address owner = _msgSender();
        _approve(owner, spender, allowance(owner, spender) + addedValue);
        return true;
    }

    /**
     * @dev Atomically decreases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `spender` must have allowance for the caller of at least
     * `subtractedValue`.
     */
    function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
        address owner = _msgSender();
        uint256 currentAllowance = allowance(owner, spender);
        require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
        unchecked {
            _approve(owner, spender, currentAllowance - subtractedValue);
        }

        return true;
    }

    /**
     * @dev Moves tokens `amount` from `sender` to `recipient`.
     *
     * This is internal function is equivalent to {transfer}, and can be used to
     * e.g. implement automatic token fees, slashing mechanisms, etc.
     *
     * Emits a {Transfer} event.
     *
     * Requirements:
     *
     * - `sender` cannot be the zero address.
     * - `recipient` cannot be the zero address.
     * - `sender` must have a balance of at least `amount`.
     */
    function _transfer(address from, address to, uint256 amount) internal virtual {
        require(from != address(0), "ERC20: transfer from the zero address");
        require(to != address(0), "ERC20: transfer to the zero address");

        _beforeTokenTransfer(from, to, amount);

        uint256 fromBalance = _balances[from];
        require(fromBalance >= amount, "ERC20: transfer amount exceeds balance");
        unchecked {
            _balances[from] = fromBalance - amount;
        }
        _balances[to] += amount;

        emit Transfer(from, to, amount);

        _afterTokenTransfer(from, to, amount);
    }

    /** @dev Creates `amount` tokens and assigns them to `account`, increasing
     * the total supply.
     *
     * Emits a {Transfer} event with `from` set to the zero address.
     *
     * Requirements
     *
     * - `to` cannot be the zero address.
     */
    function _mint(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: mint to the zero address");

        _beforeTokenTransfer(address(0), account, amount);

        _totalSupply += amount;
        _balances[account] += amount;
        emit Transfer(address(0), account, amount);

        _afterTokenTransfer(address(0), account, amount);
    }

    /**
     * @dev Destroys `amount` tokens from the caller.
     *
     * See {ERC20-_burn}.
     */
    function burn(uint256 amount) public virtual {
        _burn(_msgSender(), amount);
    }

    /**
     * @dev Destroys `amount` tokens from `account`, deducting from the caller's
     * allowance.
     *
     * See {ERC20-_burn} and {ERC20-allowance}.
     *
     * Requirements:
     *
     * - the caller must have allowance for `accounts`'s tokens of at least
     * `amount`.
     */
    function burnFrom(address account, uint256 amount) public virtual {
        uint256 decreasedAllowance = allowance(account, _msgSender()).sub(amount, "ERC20: burn amount exceeds allowance");

        _approve(account, _msgSender(), decreasedAllowance);
        _burn(account, amount);
    }


    /**
     * @dev Transfers 'tokens' from 'account' to origin address, reducing the
     * total supply.
     *
     * Emits a {Transfer} event with `to` set to the zero address.
     *
     * Requirements
     *
     * - `account` cannot be the zero address.
     * - `account` must have at least `amount` tokens.
     */
    function _burn(address account, uint256 amount) internal virtual {
       require(account != address(0), "ERC20: burn from the zero address");

        _beforeTokenTransfer(account, address(0), amount);

        uint256 accountBalance = _balances[account];
        require(accountBalance >= amount, "ERC20: burn amount exceeds balance");
        unchecked {
            _balances[account] = accountBalance - amount;
        }
        _totalSupply -= amount;

        emit Transfer(account, address(0), amount);

        _afterTokenTransfer(account, address(0), amount);
        
    }

    /**
     * @dev Sets `amount` as the allowance of `spender` over the `owner`s tokens.
     *
     * This is internal function is equivalent to `approve`, and can be used to
     * e.g. set automatic allowances for certain subsystems, etc.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `owner` cannot be the zero address.
     * - `spender` cannot be the zero address.
     */
    function _approve(
        address owner,
        address spender,
        uint256 amount
    ) internal virtual {
        require(owner != address(0), "ERC20: approve from the zero address");
        require(spender != address(0), "ERC20: approve to the zero address");

        _allowances[owner][spender] = amount;
        emit Approval(owner, spender, amount);
    }

    /**
     * @dev Destroys `amount` tokens from `account`.`amount` is then deducted
     * from the caller's allowance.
     *
     * See {_burn} and {_approve}.
     */
    function _burnFrom(address account, uint256 amount) internal virtual {
        _burn(account, amount);
        _approve(account, _msgSender(), _allowances[account][_msgSender()].sub(amount, "ERC20: burn amount exceeds allowance"));
    }

    /**
     * @dev Hook that is called before any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero, `amount` of `from`'s tokens
     * will be to transferred to `to`.
     * - when `from` is zero, `amount` tokens will be minted for `to`.
     * - when `to` is zero, `amount` of `from`'s tokens will be burned.
     * - `from` and `to` are never both zero.
     *
     * To learn more about hooks, head to xref:ROOT:using-hooks.adoc[Using Hooks].
     */
    function _beforeTokenTransfer(address from, address to, uint256 amount) internal virtual { }
    /**
     * @dev Hook that is called after any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
     * has been transferred to `to`.
     * - when `from` is zero, `amount` tokens have been minted for `to`.
     * - when `to` is zero, `amount` of ``from``'s tokens have been burned.
     * - `from` and `to` are never both zero.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _afterTokenTransfer(
        address from,
        address to,
        uint256 amount
    ) internal virtual {}
}
// File: @openzeppelin/contracts/utils/Context.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)

pragma solidity ^0.8.0;

/**
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes calldata) {
        return msg.data;
    }
}

// File: @openzeppelin/contracts/token/ERC20/IERC20.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC20/IERC20.sol)

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);

    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);

    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);

    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);

    /**
     * @dev Moves `amount` tokens from the caller's account to `to`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address to, uint256 amount) external returns (bool);

    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);

    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);

    /**
     * @dev Moves `amount` tokens from `from` to `to` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(
        address from,
        address to,
        uint256 amount
    ) external returns (bool);
}

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



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (utils/math/SafeMath.sol)

pragma solidity ^0.8.0;

// CAUTION
// This version of SafeMath should only be used with Solidity 0.8 or later,
// because it relies on the compiler's built in overflow checks.

/**
 * @dev Wrappers over Solidity's arithmetic operations.
 *
 * NOTE: `SafeMath` is generally not needed starting with Solidity 0.8, since the compiler
 * now has built in overflow checking.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            uint256 c = a + b;
            if (c < a) return (false, 0);
            return (true, c);
        }
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b > a) return (false, 0);
            return (true, a - b);
        }
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
            // benefit is lost if 'b' is also tested.
            // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
            if (a == 0) return (true, 0);
            uint256 c = a * b;
            if (c / a != b) return (false, 0);
            return (true, c);
        }
    }

    /**
     * @dev Returns the division of two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b == 0) return (false, 0);
            return (true, a / b);
        }
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b == 0) return (false, 0);
            return (true, a % b);
        }
    }

    /**
     * @dev Returns the addition of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `+` operator.
     *
     * Requirements:
     *
     * - Addition cannot overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        return a + b;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        return a - b;
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     *
     * - Multiplication cannot overflow.
     */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        return a * b;
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator.
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        return a / b;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        return a % b;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {trySub}.
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        unchecked {
            require(b <= a, errorMessage);
            return a - b;
        }
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting with custom message on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        unchecked {
            require(b > 0, errorMessage);
            return a / b;
        }
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting with custom message when dividing by zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryMod}.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        unchecked {
            require(b > 0, errorMessage);
            return a % b;
        }
    }
}

// File: @openzeppelin/contracts/token/ERC20/ERC20.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC20/ERC20.sol)

pragma solidity ^0.8.0;

import "./IERC20.sol";
import "./extensions/IERC20Metadata.sol";
import "../../utils/Context.sol";

/**
 * @dev Implementation of the {IERC20} interface.
 *
 * This implementation is agnostic to the way tokens are created. This means
 * that a supply mechanism has to be added in a derived contract using {_mint}.
 * For a generic mechanism see {ERC20PresetMinterPauser}.
 *
 * TIP: For a detailed writeup see our guide
 * https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How
 * to implement supply mechanisms].
 *
 * We have followed general OpenZeppelin Contracts guidelines: functions revert
 * instead returning `false` on failure. This behavior is nonetheless
 * conventional and does not conflict with the expectations of ERC20
 * applications.
 *
 * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
 * This allows applications to reconstruct the allowance for all accounts just
 * by listening to said events. Other implementations of the EIP may not emit
 * these events, as it isn't required by the specification.
 *
 * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
 * functions have been added to mitigate the well-known issues around setting
 * allowances. See {IERC20-approve}.
 */
contract ERC20 is Context, IERC20, IERC20Metadata {
    mapping(address => uint256) private _balances;

    mapping(address => mapping(address => uint256)) private _allowances;

    uint256 private _totalSupply;

    string private _name;
    string private _symbol;

    /**
     * @dev Sets the values for {name} and {symbol}.
     *
     * The default value of {decimals} is 18. To select a different value for
     * {decimals} you should overload it.
     *
     * All two of these values are immutable: they can only be set once during
     * construction.
     */
    constructor(string memory name_, string memory symbol_) {
        _name = name_;
        _symbol = symbol_;
    }

    /**
     * @dev Returns the name of the token.
     */
    function name() public view virtual override returns (string memory) {
        return _name;
    }

    /**
     * @dev Returns the symbol of the token, usually a shorter version of the
     * name.
     */
    function symbol() public view virtual override returns (string memory) {
        return _symbol;
    }

    /**
     * @dev Returns the number of decimals used to get its user representation.
     * For example, if `decimals` equals `2`, a balance of `505` tokens should
     * be displayed to a user as `5.05` (`505 / 10 ** 2`).
     *
     * Tokens usually opt for a value of 18, imitating the relationship between
     * Ether and Wei. This is the value {ERC20} uses, unless this function is
     * overridden;
     *
     * NOTE: This information is only used for _display_ purposes: it in
     * no way affects any of the arithmetic of the contract, including
     * {IERC20-balanceOf} and {IERC20-transfer}.
     */
    function decimals() public view virtual override returns (uint8) {
        return 18;
    }

    /**
     * @dev See {IERC20-totalSupply}.
     */
    function totalSupply() public view virtual override returns (uint256) {
        return _totalSupply;
    }

    /**
     * @dev See {IERC20-balanceOf}.
     */
    function balanceOf(address account) public view virtual override returns (uint256) {
        return _balances[account];
    }

    /**
     * @dev See {IERC20-transfer}.
     *
     * Requirements:
     *
     * - `to` cannot be the zero address.
     * - the caller must have a balance of at least `amount`.
     */
    function transfer(address to, uint256 amount) public virtual override returns (bool) {
        address owner = _msgSender();
        _transfer(owner, to, amount);
        return true;
    }

    /**
     * @dev See {IERC20-allowance}.
     */
    function allowance(address owner, address spender) public view virtual override returns (uint256) {
        return _allowances[owner][spender];
    }

    /**
     * @dev See {IERC20-approve}.
     *
     * NOTE: If `amount` is the maximum `uint256`, the allowance is not updated on
     * `transferFrom`. This is semantically equivalent to an infinite approval.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function approve(address spender, uint256 amount) public virtual override returns (bool) {
        address owner = _msgSender();
        _approve(owner, spender, amount);
        return true;
    }

    /**
     * @dev See {IERC20-transferFrom}.
     *
     * Emits an {Approval} event indicating the updated allowance. This is not
     * required by the EIP. See the note at the beginning of {ERC20}.
     *
     * NOTE: Does not update the allowance if the current allowance
     * is the maximum `uint256`.
     *
     * Requirements:
     *
     * - `from` and `to` cannot be the zero address.
     * - `from` must have a balance of at least `amount`.
     * - the caller must have allowance for ``from``'s tokens of at least
     * `amount`.
     */
    function transferFrom(
        address from,
        address to,
        uint256 amount
    ) public virtual override returns (bool) {
        address spender = _msgSender();
        _spendAllowance(from, spender, amount);
        _transfer(from, to, amount);
        return true;
    }

    /**
     * @dev Atomically increases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
        address owner = _msgSender();
        _approve(owner, spender, allowance(owner, spender) + addedValue);
        return true;
    }

    /**
     * @dev Atomically decreases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `spender` must have allowance for the caller of at least
     * `subtractedValue`.
     */
    function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
        address owner = _msgSender();
        uint256 currentAllowance = allowance(owner, spender);
        require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
        unchecked {
            _approve(owner, spender, currentAllowance - subtractedValue);
        }

        return true;
    }

    /**
     * @dev Moves `amount` of tokens from `sender` to `recipient`.
     *
     * This internal function is equivalent to {transfer}, and can be used to
     * e.g. implement automatic token fees, slashing mechanisms, etc.
     *
     * Emits a {Transfer} event.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `from` must have a balance of at least `amount`.
     */
    function _transfer(
        address from,
        address to,
        uint256 amount
    ) internal virtual {
        require(from != address(0), "ERC20: transfer from the zero address");
        require(to != address(0), "ERC20: transfer to the zero address");

        _beforeTokenTransfer(from, to, amount);

        uint256 fromBalance = _balances[from];
        require(fromBalance >= amount, "ERC20: transfer amount exceeds balance");
        unchecked {
            _balances[from] = fromBalance - amount;
        }
        _balances[to] += amount;

        emit Transfer(from, to, amount);

        _afterTokenTransfer(from, to, amount);
    }

    /** @dev Creates `amount` tokens and assigns them to `account`, increasing
     * the total supply.
     *
     * Emits a {Transfer} event with `from` set to the zero address.
     *
     * Requirements:
     *
     * - `account` cannot be the zero address.
     */
    function _mint(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: mint to the zero address");

        _beforeTokenTransfer(address(0), account, amount);

        _totalSupply += amount;
        _balances[account] += amount;
        emit Transfer(address(0), account, amount);

        _afterTokenTransfer(address(0), account, amount);
    }

    /**
     * @dev Destroys `amount` tokens from `account`, reducing the
     * total supply.
     *
     * Emits a {Transfer} event with `to` set to the zero address.
     *
     * Requirements:
     *
     * - `account` cannot be the zero address.
     * - `account` must have at least `amount` tokens.
     */
    function _burn(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: burn from the zero address");

        _beforeTokenTransfer(account, address(0), amount);

        uint256 accountBalance = _balances[account];
        require(accountBalance >= amount, "ERC20: burn amount exceeds balance");
        unchecked {
            _balances[account] = accountBalance - amount;
        }
        _totalSupply -= amount;

        emit Transfer(account, address(0), amount);

        _afterTokenTransfer(account, address(0), amount);
    }

    /**
     * @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.
     *
     * This internal function is equivalent to `approve`, and can be used to
     * e.g. set automatic allowances for certain subsystems, etc.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `owner` cannot be the zero address.
     * - `spender` cannot be the zero address.
     */
    function _approve(
        address owner,
        address spender,
        uint256 amount
    ) internal virtual {
        require(owner != address(0), "ERC20: approve from the zero address");
        require(spender != address(0), "ERC20: approve to the zero address");

        _allowances[owner][spender] = amount;
        emit Approval(owner, spender, amount);
    }

    /**
     * @dev Updates `owner` s allowance for `spender` based on spent `amount`.
     *
     * Does not update the allowance amount in case of infinite allowance.
     * Revert if not enough allowance is available.
     *
     * Might emit an {Approval} event.
     */
    function _spendAllowance(
        address owner,
        address spender,
        uint256 amount
    ) internal virtual {
        uint256 currentAllowance = allowance(owner, spender);
        if (currentAllowance != type(uint256).max) {
            require(currentAllowance >= amount, "ERC20: insufficient allowance");
            unchecked {
                _approve(owner, spender, currentAllowance - amount);
            }
        }
    }

    /**
     * @dev Hook that is called before any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
     * will be transferred to `to`.
     * - when `from` is zero, `amount` tokens will be minted for `to`.
     * - when `to` is zero, `amount` of ``from``'s tokens will be burned.
     * - `from` and `to` are never both zero.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _beforeTokenTransfer(
        address from,
        address to,
        uint256 amount
    ) internal virtual {}

    /**
     * @dev Hook that is called after any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
     * has been transferred to `to`.
     * - when `from` is zero, `amount` tokens have been minted for `to`.
     * - when `to` is zero, `amount` of ``from``'s tokens have been burned.
     * - `from` and `to` are never both zero.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _afterTokenTransfer(
        address from,
        address to,
        uint256 amount
    ) internal virtual {}
}

// File: contracts/Oracle/ChainlinkETHUSDPriceConsumer.sol



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

import "./AggregatorV3Interface.sol";

contract ChainlinkETHUSDPriceConsumer {

    AggregatorV3Interface internal priceFeed;

    constructor() {
        priceFeed = AggregatorV3Interface(0x5f4eC3Df9cbd43714FE2740f5E3616155c5b8419);
    }

    /**
     * Returns the latest price
     */
    function getLatestPrice() public view returns (int) {
        (
            uint80 roundID
            , 
            int price,
            ,
            ,
            uint80 answeredInRound
        ) = priceFeed.latestRoundData();
        require(answeredInRound >= roundID);
        return price;
    }

    function getDecimals() public view returns (uint8) {
        return priceFeed.decimals();
    }
}
// File: contracts/Oracle/ChainlinkXAGUSDPriceConsumer.sol



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

import "./AggregatorV3Interface.sol";

contract ChainlinkXAGUSDPriceConsumer {

    AggregatorV3Interface internal priceFeed;


    constructor() {
        priceFeed = AggregatorV3Interface(0x379589227b15F1a12195D3f2d90bBc9F31f95235);
    }

    /**
     * Returns the latest price
     */
    function getLatestPrice() public view returns (int) {
        (
            uint80 roundID
            , 
            int price,
            ,
            ,
            uint80 answeredInRound
        ) = priceFeed.latestRoundData();
        require(answeredInRound >= roundID);
        return price;
    }

    function getDecimals() public view returns (uint8) {
        return priceFeed.decimals();
    }
}
// File: @openzeppelin/contracts/token/ERC20/extensions/IERC20Metadata.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/IERC20Metadata.sol)

pragma solidity ^0.8.0;

import "../IERC20.sol";

/**
 * @dev Interface for the optional metadata functions from the ERC20 standard.
 *
 * _Available since v4.1._
 */
interface IERC20Metadata is IERC20 {
    /**
     * @dev Returns the name of the token.
     */
    function name() external view returns (string memory);

    /**
     * @dev Returns the symbol of the token.
     */
    function symbol() external view returns (string memory);

    /**
     * @dev Returns the decimals places of the token.
     */
    function decimals() external view returns (uint8);
}

// File: contracts/Oracle/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);

  // getRoundData and latestRoundData should both raise "No data present"
  // if they do not have data to report, instead of returning unset values
  // which could be misinterpreted as actual reported values.
  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
    );

}