Cryo Explorer Ethereum Mainnet

// SPDX-License-Identifier: MIT
// Author: A.P
// Organization: Rare Art
// Development: Kibernacia
// Product: R4RE
// Version: 1.0.0
// Link: https://linktr.ee/rareuniverse
pragma solidity >=0.8.23 <0.9.0;

// OpenZeppelin
import {ERC20} from "@openzeppelin/contracts/token/ERC20/ERC20.sol";
import {Ownable} from "@openzeppelin/contracts/access/Ownable.sol";

// Uniswap V2
import {IUniswapV2Factory} from "@uniswap/v2-core/contracts/interfaces/IUniswapV2Factory.sol";
import {IUniswapV2Router02} from "@uniswap/v2-periphery/contracts/interfaces/IUniswapV2Router02.sol";

// R4RE
import {R4REPool} from "./R4REPool.sol";

contract R4RE is ERC20, Ownable, R4REPool {
    /// @notice Stores token name.
    /// @dev Stores constant string.
    string private constant _NAME = "R4RE";

    /// @notice Stores token symbol.
    /// @dev Stores constant string.
    string private constant _SYMBOL = "R4RE";

    /// @notice Stores max wallet factor.
    /// @dev Stores number.
    uint32 private _maxWalletFactor = 50;

    /// @notice Stores max transaction factor.
    /// @dev Stores number.
    uint32 private _maxTransactionFactor = 50;

    /// @notice Stores time-based restriction per address.
    /// @dev Stores map from address to timestamp.
    mapping(address => uint256) public lastTransactionTimestamp;

    /// @notice Stores cooldown time per address.
    /// @dev Stores timestamp.
    uint256 public cooldownTime = 5 seconds;

    /// @notice Indicates whether automatic liquidity provision to the pool is enabled.
    /// @dev Set to `true` by default, allowing the contract to automatically add liquidity. This can be toggled to enable or disable the feature.
    bool public autoLiquidityProviding = true;

    /// @notice Stores tax factor.
    /// @dev Stores number.
    uint32 private _taxFactor = 100;

    /// @notice Stores buy tax.
    /// @dev Stores number.
    uint32 public buyTax = 6; // 6.00% (default)

    /// @notice Stores sell tax.
    /// @dev Stores number.
    uint32 public sellTax = 6; // 6.00% (default)

    /// @notice Defines the fee percentage for liquidity provision.
    /// @notice LP tax will be fractionated from both buy and sell tax.
    /// @dev Stored number.
    uint32 public liquidityFee = 50; // 50.00% (default)

    /// @notice Stores tax collecting address.
    /// @dev Stores address.
    address payable public taxCollector;

    /// @notice Stores excluded from fee addresses.
    /// @dev Stores map from address to bool.
    mapping(address => bool) public isExcluded;

    constructor(
        uint256 initialSupply
    ) ERC20(_NAME, _SYMBOL) Ownable(_msgSender()) {
        // Create token supply
        _mint(_msgSender(), initialSupply);

        // Set tax collection address
        taxCollector = payable(_msgSender());

        // Setup uniswap v2 router
        uniswapV2Router = IUniswapV2Router02(
            0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D
        );

        // Set uniswap v2 factory
        IUniswapV2Factory uniswapV2Factory = IUniswapV2Factory(
            uniswapV2Router.factory()
        );

        // Create uniswap v2 pair
        uniswapV2Pair = uniswapV2Factory.createPair(
            address(this),
            uniswapV2Router.WETH()
        );

        // Exclude owner, contract, uniswap v2 router and pair from fees by default
        isExcluded[_msgSender()] = true;
        isExcluded[address(this)] = true;
        isExcluded[address(uniswapV2Router)] = true;
        isExcluded[uniswapV2Pair] = true;
    }

    // Modifiers
    /**
     * @dev Throws if called by any account other than the tax collector.
     */
    modifier onlyTaxCollector() {
        if (taxCollector != _msgSender()) {
            revert OwnableUnauthorizedAccount(_msgSender());
        }

        _;
    }

    /**
     * @dev Throws if transaction conditions are not valid.
     * @param from The address to which tokens are being transferred.
     * @param to The address to which tokens are being transferred.
     * @param value The amount of tokens being transferred.
     */
    modifier validateTransfer(
        address from,
        address to,
        uint256 value
    ) {
        // Validation
        if (from == address(0)) {
            revert TransferFromZeroAddress();
        }

        if (to == address(0)) {
            revert TransferToZeroAddress();
        }

        if (!isExcluded[from] && isUniswap(to)) {
            // Max transaction size validation
            if (value > maxTransactionSize()) {
                revert MaxTransactionSizeExceeded();
            }

            // Time-based restriction validation
            uint256 timestamp = lastTransactionTimestamp[from];
            uint256 restriction = timestamp + cooldownTime;
            if (block.timestamp < restriction) {
                revert TransferTimeRestriction();
            }

            // Set timestamp
            lastTransactionTimestamp[from] = block.timestamp;
        }

        if (isUniswap(from) && !isExcluded[to]) {
            // Max transaction size validation
            if (value > maxTransactionSize()) {
                revert MaxTransactionSizeExceeded();
            }

            // Time-based restriction validation
            uint256 timestamp = lastTransactionTimestamp[to];
            uint256 restriction = timestamp + cooldownTime;
            if (block.timestamp < restriction) {
                revert TransferTimeRestriction();
            }

            // Set timestamp
            lastTransactionTimestamp[to] = block.timestamp;
        }

        if (!isExcluded[to]) {
            // Max wallet size validation
            if ((balanceOf(to) + value) > maxWalletSize()) {
                revert MaxWalletSizeExceeded();
            }
        }

        // Cooldown transfer
        if (!isExcluded[from] && !isExcluded[to]) {
            lastTransactionTimestamp[to] = lastTransactionTimestamp[from];
        }

        _;
    }

    /**
     * @dev Overrides transfer function to add custom logic for trading protections and taxes.
     * @notice This function is used to transfer tokens with additional features such as trading protections and taxes.
     * @param to The address to which tokens are transferred.
     * @param value The amount of tokens to be transferred.
     * @return A boolean that indicates whether the operation succeeded.
     */
    function transfer(
        address to,
        uint256 value
    ) public override validateTransfer(_msgSender(), to, value) returns (bool) {
        // Parameters
        uint256 amountAfterTax = value;
        uint256 taxedAmount = 0;
        bool deductTax = false;

        // Swap Token to ETH
        if (_msgSender() == uniswapV2Pair) {
            // Verification
            if (!isExcluded[to]) {
                deductTax = true;
            }

            if (deductTax) {
                // Taxation
                (amountAfterTax, taxedAmount) = calculateTax(value, buyTax);

                // Collect tax
                if (taxedAmount > 0) {
                    // Update
                    super._update(_msgSender(), address(this), taxedAmount);

                    // Event
                    emit Taxed(_msgSender(), taxedAmount);
                }

                return super.transfer(to, amountAfterTax);
            } else {
                return super.transfer(to, value);
            }
        }

        return super.transfer(to, value);
    }

    /**
     * @dev Overrides transferFrom function to add custom logic for trading protections and taxes.
     * @notice This function is used to transfer tokens from one address to another with additional features such as trading protections and taxes.
     * @param from The address from which tokens are transferred.
     * @param to The address to which tokens are transferred.
     * @param value The amount of tokens to be transferred.
     * @return A boolean that indicates whether the operation succeeded.
     */
    function transferFrom(
        address from,
        address to,
        uint256 value
    ) public override validateTransfer(from, to, value) returns (bool) {
        // Parameters
        uint256 amountAfterTax = value;
        uint256 taxedAmount = 0;
        bool deductTax = false;

        // Swap ETH to Token
        if (from == uniswapV2Pair) {
            // Verification
            if (!isExcluded[to]) {
                deductTax = true;
            }

            if (deductTax) {
                // Taxation
                (amountAfterTax, taxedAmount) = calculateTax(value, buyTax);

                // Collect tax
                if (taxedAmount > 0) {
                    // Update
                    super._update(from, address(this), taxedAmount);

                    // Event
                    emit Taxed(to, taxedAmount);
                }

                return super.transferFrom(from, to, amountAfterTax);
            } else {
                return super.transferFrom(from, to, value);
            }
        }

        // Swap Token to ETH
        if (to == uniswapV2Pair) {
            // Verification
            if (!isExcluded[from]) {
                deductTax = true;
            }

            if (deductTax) {
                // Taxation
                (amountAfterTax, taxedAmount) = calculateTax(value, sellTax);

                // Collect tax
                if (taxedAmount > 0) {
                    // Update
                    super._update(from, address(this), taxedAmount);

                    if (autoLiquidityProviding) {
                        // Tax
                        uint256 amountTax = 0;
                        uint256 amountLiquidity = 0;
                        uint256 amountSwap = balanceOf(address(this));

                        // Distribution
                        (amountTax, amountLiquidity) = calculateTax(
                            balanceOf(address(this)),
                            liquidityFee
                        );

                        // Validation
                        if (amountLiquidity >= 2) {
                            amountSwap = amountTax + amountLiquidity / 2;
                        }

                        // Swap
                        swapTokensForEth(amountSwap);

                        if (autoLiquidityProviding) {
                            // Distribution
                            uint amountToken = balanceOf(address(this));
                            uint amountETH = quote(amountToken);

                            emit Quote(
                                amountToken,
                                amountETH,
                                address(this).balance
                            );

                            // Add Liquidity
                            if (address(this).balance > amountETH) {
                                addLiquidity(amountToken, amountETH);
                            }
                        }

                        // Distribute
                        transferTax();
                    } else {
                        // Swap
                        swapTokensForEth(balanceOf(address(this)));

                        // Distribute
                        transferTax();
                    }

                    // Event
                    emit Taxed(from, taxedAmount);
                }

                return super.transferFrom(from, to, amountAfterTax);
            } else {
                return super.transferFrom(from, to, value);
            }
        }

        return super.transferFrom(from, to, value);
    }

    /**
     * @dev Checks if the given address is either the Uniswap V2 Router or the Uniswap V2 Pair.
     * @param sender The address to be checked.
     * @return Whether the address is associated with Uniswap.
     */
    function isUniswap(address sender) private view returns (bool) {
        return sender == address(uniswapV2Router) || sender == uniswapV2Pair;
    }

    /**
     * @notice Returns the max wallet size per address.
     * @dev Returns a number calculated based on supply divided by the factor.
     */
    function maxWalletSize() public view returns (uint256) {
        return totalSupply() / _maxWalletFactor;
    }

    /**
     * @notice Returns the max transaction size per transfer.
     * @dev Returns a number calculated based on supply divided by the factor.
     */
    function maxTransactionSize() public view returns (uint256) {
        return totalSupply() / _maxTransactionFactor;
    }

    /**
     * @dev Calculates the amount after applying a tax to the given amount.
     * @param amount The original amount on which tax is to be applied.
     * @param tax The tax rate to be applied, represented as a percentage (e.g., 5 for 5%).
     * @return amountAfterTax The amount after applying the tax.
     * @return taxedAmount The calculated tax amount.
     *
     * @notice This function is a view function, meaning it does not modify the state of the contract.
     * @notice If the tax is set to 0, the original amount is returned with no tax applied.
     * @notice If the product of amount and tax is less than a predefined factor (_taxFactor),
     * the tax is considered negligible and the amount is returned with no tax applied.
     * @notice If the original amount is less than 2, no tax is applied, and the original amount is returned.
     * @notice If none of the above conditions are met, the tax is calculated and subtracted from the original amount.
     */
    function calculateTax(
        uint256 amount,
        uint32 tax
    ) public view returns (uint256 amountAfterTax, uint256 taxedAmount) {
        // Validation Zero Tax
        if (tax == 0) return (amount, 0);

        // Validation Small Amount
        if ((amount * tax) < _taxFactor) {
            if (amount < 2) {
                return (amount, 0);
            } else {
                taxedAmount = amount / 2;
                amountAfterTax = amount - taxedAmount;

                return (amountAfterTax, taxedAmount);
            }
        }

        taxedAmount = (amount * tax) / _taxFactor;
        amountAfterTax = amount - taxedAmount;

        return (amountAfterTax, taxedAmount);
    }

    /**
     * @dev Sets a new tax collector for the contract.
     * @param newTaxCollector The address of the new tax collector.
     *
     * @notice This function is external and can be called by anyone, but it is restricted to only the current tax collector.
     * @notice Only the current tax collector has the authority to set a new tax collector.
     * @notice The new tax collector's address is stored, and the old tax collector is replaced with the new one.
     * @notice The new tax collector is marked as excluded to prevent taxation on themselves.
     * @notice Emits a TaxCollectorModified event with details about the modification, including the old and new tax collector's addresses.
     */
    function setTaxCollector(
        address newTaxCollector
    ) external onlyTaxCollector {
        // Set
        address oldTaxCollector = taxCollector;
        taxCollector = payable(newTaxCollector);

        // Exclude
        isExcluded[newTaxCollector] = true;

        // Event
        emit TaxCollectorModified(oldTaxCollector, newTaxCollector);
    }

    /**
     * @dev Sets the exclusion status for a given account from tax calculations.
     * @param account The address of the account to be excluded or included.
     * @param exclude A boolean flag indicating whether the account should be excluded (true) or included (false).
     *
     * @notice This function is external, meaning it can only be called from outside the contract.
     * @notice Only the owner of the contract has the authority to exclude or include accounts.
     * @notice The exclusion status is updated for the specified account, affecting tax calculations.
     * @notice Emits an Excluded event with details about the modification, including the account address and exclusion status.
     */
    function setExclude(address account, bool exclude) external onlyOwner {
        // Set
        isExcluded[account] = exclude;

        // Event
        emit Excluded(account, exclude);
    }

    /**
     * @dev Sets the maximum wallet factor for the contract, which is used as a threshold for wallet balance validation.
     * @param newFactor The new maximum wallet factor to be set.
     *
     * @notice This function is external, meaning it can only be called from outside the contract.
     * @notice Only the owner of the contract has the authority to set the maximum wallet factor.
     * @notice The new maximum wallet factor must not exceed the total supply of the contract's token.
     * @notice If the new maximum wallet factor is invalid, the function reverts and emits an error message.
     * @notice Emits a FactorModified event with details about the modification, including the factor type, old factor, and new factor.
     */
    function setMaxWalletFactor(uint32 newFactor) external onlyOwner {
        // Validation
        if (newFactor > totalSupply()) {
            revert InvalidInput(
                "Max wallet factor",
                "Max wallet factor cannot exceed total supply"
            );
        }

        // Set
        uint32 oldFactor = _maxWalletFactor;
        _maxWalletFactor = newFactor;

        // Event
        emit FactorModified("Max Wallet Factor", oldFactor, newFactor);
    }

    /**
     * @dev Sets the maximum transaction factor for the contract, which is used as a threshold for transaction validation.
     * @param newFactor The new maximum transaction factor to be set.
     *
     * @notice This function is external, meaning it can only be called from outside the contract.
     * @notice Only the owner of the contract has the authority to set the maximum transaction factor.
     * @notice The new maximum transaction factor must not exceed the total supply of the contract's token.
     * @notice If the new maximum transaction factor is invalid, the function reverts and emits an error message.
     * @notice Emits a FactorModified event with details about the modification, including the factor type, old factor, and new factor.
     */
    function setMaxTransactionFactor(uint32 newFactor) external onlyOwner {
        // Validation
        if (newFactor > totalSupply()) {
            revert InvalidInput(
                "Max transaction factor",
                "Max transaction factor cannot exceed total supply"
            );
        }

        // Set
        uint32 oldFactor = _maxTransactionFactor;
        _maxTransactionFactor = newFactor;

        // Event
        emit FactorModified("Max Transaction Factor", oldFactor, newFactor);
    }

    /**
     * @dev Sets the cooldown time for transactions in the contract.
     * @param newCooldownTime The new cooldown time, representing the duration in seconds.
     *
     * @notice This function is external, meaning it can only be called from outside the contract.
     * @notice Only the owner of the contract has the authority to set the cooldown time.
     * @notice The new cooldown time is stored, affecting the time duration between transactions.
     * @notice Emits a CooldownTimeModified event with details about the modification, including the old and new cooldown times.
     */
    function setCooldownTime(uint256 newCooldownTime) external onlyOwner {
        // Set
        uint256 oldCooldownTime = cooldownTime;
        cooldownTime = newCooldownTime;

        // Event
        emit CooldownTimeModified(oldCooldownTime, newCooldownTime);
    }

    /**
     * @dev Toggles the automatic liquidity provision feature of the contract. This feature, when enabled, allows the contract to automatically provide liquidity to a paired liquidity pool.
     *
     * @notice This function is external, meaning it can only be called from outside the contract.
     * @notice Only the owner of the contract has the authority to toggle the automatic liquidity provision feature.
     * @notice Toggling this feature inverses the current state of the autoLiquidityProviding variable.
     * @notice Emits an AutoLiquiditySwitch event indicating the new state of the automatic liquidity provision feature.
     */
    function switchAutoLiquidity() external onlyOwner {
        // Set
        autoLiquidityProviding = !autoLiquidityProviding;

        // Event
        emit AutoLiquiditySwitch(autoLiquidityProviding);
    }

    /**
     * @dev Sets the tax factor for the contract, which is used as a threshold for tax division.
     * @param newTaxFactor The new tax factor to be set.
     *
     * @notice This function is external, meaning it can only be called from outside the contract.
     * @notice Only the owner of the contract has the authority to set the tax factor.
     * @notice The new tax factor must not exceed the total supply of the contract's token.
     * @notice If the new tax factor is invalid, the function reverts and emits an error message.
     * @notice Emits a FactorModified event with details about the modification, including the factor type, old factor, and new factor.
     */
    function setTaxFactor(uint32 newTaxFactor) external onlyOwner {
        // Validation
        if (_taxFactor > totalSupply()) {
            revert InvalidInput(
                "Tax Factor",
                "Tax factor cannot exceed total supply"
            );
        }

        // Set
        uint32 oldTaxFactor = newTaxFactor;
        _taxFactor = newTaxFactor;

        // Event
        emit FactorModified("Tax Factor", oldTaxFactor, newTaxFactor);
    }

    /**
     * @dev Sets the buying tax rate for the contract.
     * @param newTax The new tax rate to be set, represented as a percentage (e.g., 5 for 5%).
     *
     * @notice This function is external, meaning it can only be called from outside the contract.
     * @notice Only the owner of the contract has the authority to set the buying tax rate.
     * @notice The new tax rate must not exceed a predefined factor (_taxFactor) to prevent excessive taxation.
     * @notice If the new tax rate is invalid, the function reverts and emits an error message.
     * @notice Emits a TaxModified event with details about the modification, including the tax type, old tax rate, and new tax rate.
     */
    function setBuyTax(uint32 newTax) external onlyOwner {
        // Validation
        if (newTax > _taxFactor) {
            revert InvalidInput("Buy Tax", "Buy tax cannot exceed tax factor");
        }

        // Set
        uint32 oldTax = buyTax;
        buyTax = newTax;

        // Event
        emit TaxModified("Buy Tax", oldTax, newTax);
    }

    /**
     * @dev Sets the selling tax rate for the contract.
     * @param newTax The new tax rate to be set, represented as a percentage.
     *
     * @notice This function is external, meaning it can only be called from outside the contract.
     * @notice Only the owner of the contract has the authority to set the selling tax rate.
     * @notice The new tax rate must not exceed a predefined factor (_taxFactor) to prevent excessive taxation.
     * @notice If the new tax rate is invalid, the function reverts and emits an error message.
     * @notice Emits a TaxModified event with details about the modification, including the tax type, old tax rate, and new tax rate.
     */
    function setSellTax(uint32 newTax) external onlyOwner {
        // Validation
        if (newTax > _taxFactor) {
            revert InvalidInput(
                "Sell Tax",
                "Sell tax cannot exceed tax factor"
            );
        }

        // Set
        uint32 oldTax = sellTax;
        sellTax = newTax;

        // Event
        emit TaxModified("Sell Tax", oldTax, newTax);
    }

    /**
     * @dev Sets a new liquidity fee for the contract, which is applied to transactions for liquidity provision.
     * @param newTax The new liquidity fee to be set, expressed in basis points (bps). For example, a value of 50 represents a 0.5% fee.
     *
     * @notice This function is external, meaning it can only be called from outside the contract.
     * @notice Only the owner of the contract has the authority to set the liquidity fee.
     * @notice The new liquidity fee must not exceed the predefined tax factor limit. If it does, the function reverts with an "InvalidInput" error.
     * @notice Emits a `TaxModified` event with details about the modification, including the tax type ("LP Tax"), old tax rate, and new tax rate.
     */
    function setliquidityFee(uint32 newTax) external onlyOwner {
        // Validation
        if (newTax > _taxFactor) {
            revert InvalidInput("LP Tax", "LP tax cannot exceed tax factor");
        }

        // Set
        uint32 oldTax = liquidityFee;
        liquidityFee = newTax;

        // Event
        emit TaxModified("LP Tax", oldTax, newTax);
    }

    /**
     * @dev Adds liquidity to the Uniswap V2 liquidity pool using a specified amount of tokens and ETH.
     * The function first verifies the Uniswap V2 Router's address, then approves the router to spend the tokens,
     * and finally attempts to add liquidity to the pool. It handles success or failure of liquidity addition.
     * @param amountToken The amount of tokens to add to the pool.
     * @param amountETH The amount of ETH to add to the pool, sent along with the transaction.
     *
     * @notice This function is private, meaning it can only be called from within the contract itself.
     * @notice Before calling this function, ensure that the Uniswap V2 Router is set and valid.
     * @notice The function approves the Uniswap V2 Router to spend the specified `amountToken`.
     * @notice Attempts to add `amountToken` tokens and `amountETH` ETH to the Uniswap V2 liquidity pool.
     * If successful, emits a `LiquidityAdded` event with the amounts used and liquidity tokens received.
     * @notice If the attempt to add liquidity fails due to a revert with a reason, emits a `LiquidityAdditionFailed` event with the reason.
     * @notice If the attempt fails without a revert reason, emits a `LiquidityAdditionFailedBytes` event with the low-level data.
     */
    function addLiquidity(uint amountToken, uint amountETH) private {
        // Verification
        if (address(uniswapV2Router) == address(0)) {
            revert UniswapV2InvalidRouter(address(0));
        }

        // Approve the Uniswap V2 router to spend the token amount
        _approve(address(this), address(uniswapV2Router), amountToken);

        // Add tokens and ETH to the liquidity pool
        try
            uniswapV2Router.addLiquidityETH{value: amountETH}(
                address(this),
                amountToken,
                0, // Consider setting non-zero slippage limits for production
                0, // Consider setting non-zero slippage limits for production
                address(taxCollector),
                block.timestamp + 600
            )
        returns (uint amountTokenUsed, uint amountETHUsed, uint liquidity) {
            // Handle successful liquidity addition
            // e.g., Emit an event or execute further logic as needed
            emit LiquidityAdded(amountTokenUsed, amountETHUsed, liquidity);
        } catch Error(string memory reason) {
            // Handle a revert with a reason from the Uniswap V2 Router
            // e.g., Emit an event or revert the transaction
            emit LiquidityAdditionFailed(reason);
        } catch (bytes memory lowLevelData) {
            // Handle a failure without a revert reason from the Uniswap V2 Router
            // e.g., Emit an event or revert the transaction
            emit LiquidityAdditionFailedBytes(lowLevelData);
        }
    }

    /**
     * @dev Initiates the swap of Tokens for ETH and distributes the resulting ETH.
     * @dev Accessible only by the contract owner.
     */
    function swap() external onlyOwner {
        // Swap
        swapTokensForEth(balanceOf(address(this)));

        // Distribute
        transferTax();

        // Event
        emit Swap();
    }

    /**
     * @dev Internal function to swap Tokens for ETH using the Uniswap V2 Router.
     * @param amount The amount of tokens to be swapped.
     */
    function swapTokensForEth(uint256 amount) private {
        // Verification
        if (address(uniswapV2Router) == address(0)) {
            revert UniswapV2InvalidRouter(address(0));
        }

        // Approve the Uniswap V2 router to spend the token amount
        _approve(address(this), address(uniswapV2Router), amount);

        // Parameters
        address[] memory path = new address[](2);

        // Configuration
        path[0] = address(this);
        path[1] = uniswapV2Router.WETH();

        // Swap tokens for ETH
        uniswapV2Router.swapExactTokensForETHSupportingFeeOnTransferTokens(
            amount,
            0,
            path,
            address(this),
            block.timestamp + 600
        );
    }

    /**
     * @dev Internal function to transfer collected tax to the designated tax collector address.
     */
    function transferTax() private {
        // Parameter
        uint256 tax = address(this).balance;

        if (tax > 0) {
            taxCollector.transfer(tax);
        }
    }

    /**
     * @dev Fallback function to receive ETH.
     */
    receive() external payable {}

    /**
     * @dev Fallback function to receive ETH.
     */
    fallback() external payable {}
}

// SPDX-License-Identifier: MIT
// Author: A.P
// Organization: Rare Art
// Development: Kibernacia
// Product: R4RE
// Version: 1.0.0
// Link: https://linktr.ee/rareuniverse
pragma solidity >=0.8.23 <0.9.0;

// OpenZeppelin
import {Context} from "@openzeppelin/contracts/utils/Context.sol";
import {Ownable} from "@openzeppelin/contracts/access/Ownable.sol";

// Uniswap V2
import {IUniswapV2Pair} from "@uniswap/v2-core/contracts/interfaces/IUniswapV2Pair.sol";
import {IUniswapV2Router02} from "@uniswap/v2-periphery/contracts/interfaces/IUniswapV2Router02.sol";

// R4RE
import {R4REEvents} from "./R4REEvents.sol";
import {R4REErrors} from "./R4REErrors.sol";

/**
 * @dev R4RE Pool
 */

abstract contract R4REPool is Context, Ownable, R4REEvents, R4REErrors {
    /// @notice Stores Uniswap V2 router interface.
    /// @dev Stores IUniswapV2Router02 interface.
    IUniswapV2Router02 public uniswapV2Router;

    /// @notice Stores Uniswap V2 pair address.
    /// @dev Stores address.
    address public uniswapV2Pair;

    /**
     * @dev Sets the UniswapV2Router for the contract to enable interactions with the Uniswap decentralized exchange.
     * @param newUniswapV2Router The address of the new UniswapV2Router contract.
     *
     * @notice This function is external, meaning it can only be called from outside the contract.
     * @notice Only the owner of the contract has the authority to set the UniswapV2Router.
     * @notice The new UniswapV2Router address must be a valid address and not equal to address(0).
     * @notice If the new UniswapV2Router address is invalid, the function reverts and emits an error message.
     * @notice Emits a UniswapV2RouterModified event with details about the modification, including the old and new UniswapV2Router addresses.
     */
    function setUniswapV2Router(address newUniswapV2Router) external onlyOwner {
        // Verification
        if (newUniswapV2Router == address(0)) {
            revert UniswapV2InvalidRouter(address(0));
        }

        // Parameter
        address oldUniswapV2Router = address(uniswapV2Router);

        // Configuration
        uniswapV2Router = IUniswapV2Router02(newUniswapV2Router);

        // Event
        emit UniswapV2RouterModified(oldUniswapV2Router, newUniswapV2Router);
    }

    /**
     * @dev Sets the UniswapV2Pair for the contract to define the trading pair with the Uniswap decentralized exchange.
     * @param newUniswapV2Pair The address of the new UniswapV2Pair contract representing the trading pair.
     *
     * @notice This function is external, meaning it can only be called from outside the contract.
     * @notice Only the owner of the contract has the authority to set the UniswapV2Pair.
     * @notice The new UniswapV2Pair address must be a valid address and not equal to address(0).
     * @notice If the new UniswapV2Pair address is invalid, the function reverts and emits an error message.
     * @notice Emits a UniswapV2PairModified event with details about the modification, including the old and new UniswapV2Pair addresses.
     */
    function setUniswapV2Pair(address newUniswapV2Pair) external onlyOwner {
        // Verification
        if (newUniswapV2Pair == address(0)) {
            revert UniswapV2InvalidPool(address(0));
        }

        // Parameter
        address oldUniswapV2Pair = uniswapV2Pair;

        // Configuration
        uniswapV2Pair = newUniswapV2Pair;

        // Event
        emit UniswapV2PairModified(oldUniswapV2Pair, uniswapV2Pair);
    }

    /**
     * @dev Retrieves the reserve amounts of the two tokens in the Uniswap V2 pair, along with the last block timestamp when these reserves were updated.
     * This function interfaces with the Uniswap V2 pair contract to fetch its current state, which is essential for calculating accurate trading prices, understanding liquidity depth, and more.
     * The reserves and timestamp can be used by external contracts or callers to make informed decisions in DeFi operations such as swaps, liquidity provision, or arbitrage.
     *
     * @return _reserve0 The reserve amount of the first token in the Uniswap V2 pair. Token pairs in Uniswap are ordered by their contract addresses.
     * @return _reserve1 The reserve amount of the second token in the Uniswap V2 pair.
     * @return _blockTimestampLast The last block timestamp when the reserves were recorded by the pair contract. This can be used to assess the freshness of the data.
     */
    function getReserves()
        public
        view
        returns (uint _reserve0, uint _reserve1, uint32 _blockTimestampLast)
    {
        // Parameter
        IUniswapV2Pair iPair = IUniswapV2Pair(uniswapV2Pair);

        return iPair.getReserves();
    }

    /**
     * @dev Calculates the equivalent amount of ETH for a given amount of tokens based on the reserves in the liquidity pool.
     * @param amountToken The amount of tokens to convert to an equivalent amount of ETH.
     * @return amountETH The equivalent amount of ETH based on the current reserves.
     */
    function quote(uint amountToken) internal view returns (uint amountETH) {
        // Get the reserves from the liquidity pool
        (uint reserveA, uint reserveB, ) = getReserves();

        if (amountToken <= 0) revert UniswapV2InsufficientAmount();
        if (reserveA <= 0 || reserveB <= 0) {
            revert UniswapV2InsufficientLiquidity();
        }

        // Parameter
        IUniswapV2Pair iPair = IUniswapV2Pair(uniswapV2Pair);

        if (address(this) == iPair.token0()) {
            // Calculate the equivalent amount of ETH based on the reserves and the amount of tokens
            amountETH = (amountToken * reserveB) / reserveA;
        } else {
            // Calculate the equivalent amount of ETH based on the reserves and the amount of tokens
            amountETH = (amountToken * reserveA) / reserveB;
        }
    }

    /**
     * @dev Allows the owner of the contract to withdraw the contract's balance.
     *
     * @notice This function is external, meaning it can only be called from outside the contract.
     * @notice Only the owner of the contract has the authority to withdraw funds.
     * @notice The entire balance of the contract is transferred to the owner's address.
     * @notice If the withdrawal is unsuccessful, the function reverts and emits an error message.
     */
    function withdraw() external onlyOwner {
        // Withdraw
        (bool success, ) = msg.sender.call{value: address(this).balance}("");

        // Verification
        if (!success) {
            revert WidthdrawInvalid();
        }
    }
}

// SPDX-License-Identifier: MIT
// Author: A.P
// Organization: Rare Art
// Development: Kibernacia
// Product: R4RE
// Version: 1.0.0
// Link: https://linktr.ee/rareuniverse
pragma solidity >=0.8.23 <0.9.0;

/**
 * @dev R4RE Errors
 */
interface R4REErrors {
    /**
     * @dev Error indicating that the provided UniswapV2Router address is invalid.
     * @param newUniswapV2Router The address of the invalid UniswapV2Router.
     */
    error UniswapV2InvalidRouter(address newUniswapV2Router);

    /**
     * @dev Error indicating that the provided UniswapV2Pair address is invalid.
     * @param newUniswapV2Pair The address of the invalid UniswapV2Pair.
     */
    error UniswapV2InvalidPool(address newUniswapV2Pair);

    /**
     * @dev Error indicating that an operation failed because the provided amount is insufficient.
     */
    error UniswapV2InsufficientAmount();

    /**
     * @dev Error indicating that an operation failed due to insufficient liquidity in the Uniswap V2 pool.
     */
    error UniswapV2InsufficientLiquidity();

    /**
     * @dev Error indicating that a transfer from the zero address is not allowed.
     */
    error TransferFromZeroAddress();

    /**
     * @dev Error indicating that a transfer to the zero address is not allowed.
     */
    error TransferToZeroAddress();

    /**
     * @dev Error indicating that the maximum wallet size has been exceeded.
     */
    error MaxWalletSizeExceeded();

    /**
     * @dev Error indicating that the maximum transaction size has been exceeded.
     */
    error MaxTransactionSizeExceeded();

    /**
     * @dev Error indicating that a transfer is not allowed due to transfer time restrictions.
     */
    error TransferTimeRestriction();

    /**
     * @dev Error indicating that a withdrawal operation is invalid.
     */
    error WidthdrawInvalid();

    /**
     * @dev Error indicating that an input parameter is invalid.
     * @param index The index or identifier of the invalid input.
     * @param message A message describing the reason for the invalid input.
     */
    error InvalidInput(string index, string message);
}

// SPDX-License-Identifier: MIT
// Author: A.P
// Organization: Rare Art
// Development: Kibernacia
// Product: R4RE
// Version: 1.0.0
// Link: https://linktr.ee/rareuniverse
pragma solidity >=0.8.23 <0.9.0;

/**
 * @dev R4RE Events
 */
interface R4REEvents {
    /**
     * @dev Emitted when an account is excluded or included from tax calculations.
     * @param account The address of the account being excluded or included.
     * @param exclude A boolean flag indicating whether the account is excluded (true) or included (false).
     */
    event Excluded(address indexed account, bool exclude);

    /**
     * @dev Emitted when the tax collector address is modified.
     * @param oldTaxCollector The old tax collector address before modification.
     * @param newTaxCollector The new tax collector address after modification.
     */
    event TaxCollectorModified(
        address indexed oldTaxCollector,
        address indexed newTaxCollector
    );

    /**
     * @dev Emitted when a factor (e.g., tax factor, max transaction factor, max wallet factor) is modified.
     * @param factor The type of factor being modified.
     * @param oldFactor The old value of the factor before modification.
     * @param newFactor The new value of the factor after modification.
     */
    event FactorModified(
        string indexed factor,
        uint32 oldFactor,
        uint32 newFactor
    );

    /**
     * @dev Emitted when a tax rate is modified.
     * @param tax The type of tax being modified.
     * @param oldTax The old tax rate before modification.
     * @param newTax The new tax rate after modification.
     */
    event TaxModified(string indexed tax, uint32 oldTax, uint32 newTax);

    /**
     * @dev Emitted when a swap operation occurs (e.g., in the Uniswap decentralized exchange).
     */
    event Swap();

    /**
     * @dev Emitted when a recipient address is taxed.
     * @param receiver The address of the recipient being taxed.
     * @param amount The amount of the tax applied.
     */
    event Taxed(address indexed receiver, uint256 amount);

    /**
     * @dev Emitted when the UniswapV2Router address is modified.
     * @param oldUniswapV2Router The old UniswapV2Router address before modification.
     * @param newUniswapV2Router The new UniswapV2Router address after modification.
     */
    event UniswapV2RouterModified(
        address indexed oldUniswapV2Router,
        address indexed newUniswapV2Router
    );

    /**
     * @dev Emitted when the UniswapV2Pair address is modified.
     * @param oldUniswapV2Pair The old UniswapV2Pair address before modification.
     * @param newUniswapV2Pair The new UniswapV2Pair address after modification.
     */
    event UniswapV2PairModified(
        address indexed oldUniswapV2Pair,
        address indexed newUniswapV2Pair
    );

    /**
     * @dev Emitted when the cooldown time for transactions is modified.
     * @param oldCooldownTime The old cooldown time before modification.
     * @param newCooldownTime The new cooldown time after modification.
     */
    event CooldownTimeModified(
        uint256 oldCooldownTime,
        uint256 newCooldownTime
    );

    /**
     * @dev Emitted when the automatic liquidity provision setting is toggled.
     * @param autoLiquidityProviding Indicates whether automatic liquidity providing is enabled (true) or disabled (false).
     */
    event AutoLiquiditySwitch(bool indexed autoLiquidityProviding);

    /**
     * @dev Emitted when liquidity is successfully added to the liquidity pool.
     * @param amountTokenUsed The amount of tokens used to add liquidity.
     * @param amountETHUsed The amount of ETH used to add liquidity.
     * @param liquidity The amount of liquidity tokens received in return for adding liquidity.
     */
    event LiquidityAdded(
        uint256 amountTokenUsed,
        uint256 amountETHUsed,
        uint256 liquidity
    );

    /**
     * @dev Emitted when adding liquidity to the liquidity pool fails due to a reason that can be expressed in a string.
     * @param reason The reason why adding liquidity failed, described as a string.
     */
    event LiquidityAdditionFailed(string reason);

    /**
     * @dev Emitted when adding liquidity to the liquidity pool fails due to a reason that is captured in low-level bytes data.
     * @param lowLevelData The low-level bytes data representing the reason for the liquidity addition failure.
     */
    event LiquidityAdditionFailedBytes(bytes lowLevelData);

    /**
     * @dev Emitted after calculating the equivalent amount of ETH for a given amount of tokens.
     * This event helps in tracking the outcomes of quote operations, providing insights into the value conversions and the state of balances after the operation.
     * @param amountToken The amount of tokens for which the quote was calculated.
     * @param amountETH The equivalent amount of ETH for the given amount of tokens as per the current conversion rate.
     * @param balance The balance after the operation, potentially reflecting changes in reserves or liquidity.
     */
    event Quote(uint amountToken, uint amountETH, uint balance);
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.1) (utils/Context.sol)

pragma solidity ^0.8.20;

/**
 * @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;
    }

    function _contextSuffixLength() internal view virtual returns (uint256) {
        return 0;
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.0) (access/Ownable.sol)

pragma solidity ^0.8.20;

import {Context} from "../utils/Context.sol";

/**
 * @dev Contract module which provides a basic access control mechanism, where
 * there is an account (an owner) that can be granted exclusive access to
 * specific functions.
 *
 * The initial owner is set to the address provided by the deployer. This can
 * later be changed with {transferOwnership}.
 *
 * This module is used through inheritance. It will make available the modifier
 * `onlyOwner`, which can be applied to your functions to restrict their use to
 * the owner.
 */
abstract contract Ownable is Context {
    address private _owner;

    /**
     * @dev The caller account is not authorized to perform an operation.
     */
    error OwnableUnauthorizedAccount(address account);

    /**
     * @dev The owner is not a valid owner account. (eg. `address(0)`)
     */
    error OwnableInvalidOwner(address owner);

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

    /**
     * @dev Initializes the contract setting the address provided by the deployer as the initial owner.
     */
    constructor(address initialOwner) {
        if (initialOwner == address(0)) {
            revert OwnableInvalidOwner(address(0));
        }
        _transferOwnership(initialOwner);
    }

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

    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view virtual returns (address) {
        return _owner;
    }

    /**
     * @dev Throws if the sender is not the owner.
     */
    function _checkOwner() internal view virtual {
        if (owner() != _msgSender()) {
            revert OwnableUnauthorizedAccount(_msgSender());
        }
    }

    /**
     * @dev Leaves the contract without owner. It will not be possible to call
     * `onlyOwner` functions. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby disabling any functionality that is only available to the owner.
     */
    function renounceOwnership() public virtual onlyOwner {
        _transferOwnership(address(0));
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Can only be called by the current owner.
     */
    function transferOwnership(address newOwner) public virtual onlyOwner {
        if (newOwner == address(0)) {
            revert OwnableInvalidOwner(address(0));
        }
        _transferOwnership(newOwner);
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Internal function without access restriction.
     */
    function _transferOwnership(address newOwner) internal virtual {
        address oldOwner = _owner;
        _owner = newOwner;
        emit OwnershipTransferred(oldOwner, newOwner);
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.0) (token/ERC20/ERC20.sol)

pragma solidity ^0.8.20;

import {IERC20} from "./IERC20.sol";
import {IERC20Metadata} from "./extensions/IERC20Metadata.sol";
import {Context} from "../../utils/Context.sol";
import {IERC20Errors} from "../../interfaces/draft-IERC6093.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}.
 *
 * TIP: For a detailed writeup see our guide
 * https://forum.openzeppelin.com/t/how-to-implement-erc20-supply-mechanisms/226[How
 * to implement supply mechanisms].
 *
 * The default value of {decimals} is 18. To change this, you should override
 * this function so it returns a different value.
 *
 * 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.
 */
abstract contract ERC20 is Context, IERC20, IERC20Metadata, IERC20Errors {
    mapping(address account => uint256) private _balances;

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

    uint256 private _totalSupply;

    string private _name;
    string private _symbol;

    /**
     * @dev Sets the values for {name} and {symbol}.
     *
     * 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 returns (string memory) {
        return _name;
    }

    /**
     * @dev Returns the symbol of the token, usually a shorter version of the
     * name.
     */
    function symbol() public view virtual 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 default value returned by this function, unless
     * it's 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 returns (uint8) {
        return 18;
    }

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

    /**
     * @dev See {IERC20-balanceOf}.
     */
    function balanceOf(address account) public view virtual 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 `value`.
     */
    function transfer(address to, uint256 value) public virtual returns (bool) {
        address owner = _msgSender();
        _transfer(owner, to, value);
        return true;
    }

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

    /**
     * @dev See {IERC20-approve}.
     *
     * NOTE: If `value` 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 value) public virtual returns (bool) {
        address owner = _msgSender();
        _approve(owner, spender, value);
        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 `value`.
     * - the caller must have allowance for ``from``'s tokens of at least
     * `value`.
     */
    function transferFrom(address from, address to, uint256 value) public virtual returns (bool) {
        address spender = _msgSender();
        _spendAllowance(from, spender, value);
        _transfer(from, to, value);
        return true;
    }

    /**
     * @dev Moves a `value` amount of tokens from `from` to `to`.
     *
     * 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.
     *
     * NOTE: This function is not virtual, {_update} should be overridden instead.
     */
    function _transfer(address from, address to, uint256 value) internal {
        if (from == address(0)) {
            revert ERC20InvalidSender(address(0));
        }
        if (to == address(0)) {
            revert ERC20InvalidReceiver(address(0));
        }
        _update(from, to, value);
    }

    /**
     * @dev Transfers a `value` amount of tokens from `from` to `to`, or alternatively mints (or burns) if `from`
     * (or `to`) is the zero address. All customizations to transfers, mints, and burns should be done by overriding
     * this function.
     *
     * Emits a {Transfer} event.
     */
    function _update(address from, address to, uint256 value) internal virtual {
        if (from == address(0)) {
            // Overflow check required: The rest of the code assumes that totalSupply never overflows
            _totalSupply += value;
        } else {
            uint256 fromBalance = _balances[from];
            if (fromBalance < value) {
                revert ERC20InsufficientBalance(from, fromBalance, value);
            }
            unchecked {
                // Overflow not possible: value <= fromBalance <= totalSupply.
                _balances[from] = fromBalance - value;
            }
        }

        if (to == address(0)) {
            unchecked {
                // Overflow not possible: value <= totalSupply or value <= fromBalance <= totalSupply.
                _totalSupply -= value;
            }
        } else {
            unchecked {
                // Overflow not possible: balance + value is at most totalSupply, which we know fits into a uint256.
                _balances[to] += value;
            }
        }

        emit Transfer(from, to, value);
    }

    /**
     * @dev Creates a `value` amount of tokens and assigns them to `account`, by transferring it from address(0).
     * Relies on the `_update` mechanism
     *
     * Emits a {Transfer} event with `from` set to the zero address.
     *
     * NOTE: This function is not virtual, {_update} should be overridden instead.
     */
    function _mint(address account, uint256 value) internal {
        if (account == address(0)) {
            revert ERC20InvalidReceiver(address(0));
        }
        _update(address(0), account, value);
    }

    /**
     * @dev Destroys a `value` amount of tokens from `account`, lowering the total supply.
     * Relies on the `_update` mechanism.
     *
     * Emits a {Transfer} event with `to` set to the zero address.
     *
     * NOTE: This function is not virtual, {_update} should be overridden instead
     */
    function _burn(address account, uint256 value) internal {
        if (account == address(0)) {
            revert ERC20InvalidSender(address(0));
        }
        _update(account, address(0), value);
    }

    /**
     * @dev Sets `value` 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.
     *
     * Overrides to this logic should be done to the variant with an additional `bool emitEvent` argument.
     */
    function _approve(address owner, address spender, uint256 value) internal {
        _approve(owner, spender, value, true);
    }

    /**
     * @dev Variant of {_approve} with an optional flag to enable or disable the {Approval} event.
     *
     * By default (when calling {_approve}) the flag is set to true. On the other hand, approval changes made by
     * `_spendAllowance` during the `transferFrom` operation set the flag to false. This saves gas by not emitting any
     * `Approval` event during `transferFrom` operations.
     *
     * Anyone who wishes to continue emitting `Approval` events on the`transferFrom` operation can force the flag to
     * true using the following override:
     * ```
     * function _approve(address owner, address spender, uint256 value, bool) internal virtual override {
     *     super._approve(owner, spender, value, true);
     * }
     * ```
     *
     * Requirements are the same as {_approve}.
     */
    function _approve(address owner, address spender, uint256 value, bool emitEvent) internal virtual {
        if (owner == address(0)) {
            revert ERC20InvalidApprover(address(0));
        }
        if (spender == address(0)) {
            revert ERC20InvalidSpender(address(0));
        }
        _allowances[owner][spender] = value;
        if (emitEvent) {
            emit Approval(owner, spender, value);
        }
    }

    /**
     * @dev Updates `owner` s allowance for `spender` based on spent `value`.
     *
     * Does not update the allowance value in case of infinite allowance.
     * Revert if not enough allowance is available.
     *
     * Does not emit an {Approval} event.
     */
    function _spendAllowance(address owner, address spender, uint256 value) internal virtual {
        uint256 currentAllowance = allowance(owner, spender);
        if (currentAllowance != type(uint256).max) {
            if (currentAllowance < value) {
                revert ERC20InsufficientAllowance(spender, currentAllowance, value);
            }
            unchecked {
                _approve(owner, spender, currentAllowance - value, false);
            }
        }
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.0) (token/ERC20/IERC20.sol)

pragma solidity ^0.8.20;

/**
 * @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 value of tokens in existence.
     */
    function totalSupply() external view returns (uint256);

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

    /**
     * @dev Moves a `value` amount of 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 value) 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 a `value` amount of tokens 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 value) external returns (bool);

    /**
     * @dev Moves a `value` amount of tokens from `from` to `to` using the
     * allowance mechanism. `value` 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 value) external returns (bool);
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.0) (interfaces/draft-IERC6093.sol)
pragma solidity ^0.8.20;

/**
 * @dev Standard ERC20 Errors
 * Interface of the https://eips.ethereum.org/EIPS/eip-6093[ERC-6093] custom errors for ERC20 tokens.
 */
interface IERC20Errors {
    /**
     * @dev Indicates an error related to the current `balance` of a `sender`. Used in transfers.
     * @param sender Address whose tokens are being transferred.
     * @param balance Current balance for the interacting account.
     * @param needed Minimum amount required to perform a transfer.
     */
    error ERC20InsufficientBalance(address sender, uint256 balance, uint256 needed);

    /**
     * @dev Indicates a failure with the token `sender`. Used in transfers.
     * @param sender Address whose tokens are being transferred.
     */
    error ERC20InvalidSender(address sender);

    /**
     * @dev Indicates a failure with the token `receiver`. Used in transfers.
     * @param receiver Address to which tokens are being transferred.
     */
    error ERC20InvalidReceiver(address receiver);

    /**
     * @dev Indicates a failure with the `spender`’s `allowance`. Used in transfers.
     * @param spender Address that may be allowed to operate on tokens without being their owner.
     * @param allowance Amount of tokens a `spender` is allowed to operate with.
     * @param needed Minimum amount required to perform a transfer.
     */
    error ERC20InsufficientAllowance(address spender, uint256 allowance, uint256 needed);

    /**
     * @dev Indicates a failure with the `approver` of a token to be approved. Used in approvals.
     * @param approver Address initiating an approval operation.
     */
    error ERC20InvalidApprover(address approver);

    /**
     * @dev Indicates a failure with the `spender` to be approved. Used in approvals.
     * @param spender Address that may be allowed to operate on tokens without being their owner.
     */
    error ERC20InvalidSpender(address spender);
}

/**
 * @dev Standard ERC721 Errors
 * Interface of the https://eips.ethereum.org/EIPS/eip-6093[ERC-6093] custom errors for ERC721 tokens.
 */
interface IERC721Errors {
    /**
     * @dev Indicates that an address can't be an owner. For example, `address(0)` is a forbidden owner in EIP-20.
     * Used in balance queries.
     * @param owner Address of the current owner of a token.
     */
    error ERC721InvalidOwner(address owner);

    /**
     * @dev Indicates a `tokenId` whose `owner` is the zero address.
     * @param tokenId Identifier number of a token.
     */
    error ERC721NonexistentToken(uint256 tokenId);

    /**
     * @dev Indicates an error related to the ownership over a particular token. Used in transfers.
     * @param sender Address whose tokens are being transferred.
     * @param tokenId Identifier number of a token.
     * @param owner Address of the current owner of a token.
     */
    error ERC721IncorrectOwner(address sender, uint256 tokenId, address owner);

    /**
     * @dev Indicates a failure with the token `sender`. Used in transfers.
     * @param sender Address whose tokens are being transferred.
     */
    error ERC721InvalidSender(address sender);

    /**
     * @dev Indicates a failure with the token `receiver`. Used in transfers.
     * @param receiver Address to which tokens are being transferred.
     */
    error ERC721InvalidReceiver(address receiver);

    /**
     * @dev Indicates a failure with the `operator`’s approval. Used in transfers.
     * @param operator Address that may be allowed to operate on tokens without being their owner.
     * @param tokenId Identifier number of a token.
     */
    error ERC721InsufficientApproval(address operator, uint256 tokenId);

    /**
     * @dev Indicates a failure with the `approver` of a token to be approved. Used in approvals.
     * @param approver Address initiating an approval operation.
     */
    error ERC721InvalidApprover(address approver);

    /**
     * @dev Indicates a failure with the `operator` to be approved. Used in approvals.
     * @param operator Address that may be allowed to operate on tokens without being their owner.
     */
    error ERC721InvalidOperator(address operator);
}

/**
 * @dev Standard ERC1155 Errors
 * Interface of the https://eips.ethereum.org/EIPS/eip-6093[ERC-6093] custom errors for ERC1155 tokens.
 */
interface IERC1155Errors {
    /**
     * @dev Indicates an error related to the current `balance` of a `sender`. Used in transfers.
     * @param sender Address whose tokens are being transferred.
     * @param balance Current balance for the interacting account.
     * @param needed Minimum amount required to perform a transfer.
     * @param tokenId Identifier number of a token.
     */
    error ERC1155InsufficientBalance(address sender, uint256 balance, uint256 needed, uint256 tokenId);

    /**
     * @dev Indicates a failure with the token `sender`. Used in transfers.
     * @param sender Address whose tokens are being transferred.
     */
    error ERC1155InvalidSender(address sender);

    /**
     * @dev Indicates a failure with the token `receiver`. Used in transfers.
     * @param receiver Address to which tokens are being transferred.
     */
    error ERC1155InvalidReceiver(address receiver);

    /**
     * @dev Indicates a failure with the `operator`’s approval. Used in transfers.
     * @param operator Address that may be allowed to operate on tokens without being their owner.
     * @param owner Address of the current owner of a token.
     */
    error ERC1155MissingApprovalForAll(address operator, address owner);

    /**
     * @dev Indicates a failure with the `approver` of a token to be approved. Used in approvals.
     * @param approver Address initiating an approval operation.
     */
    error ERC1155InvalidApprover(address approver);

    /**
     * @dev Indicates a failure with the `operator` to be approved. Used in approvals.
     * @param operator Address that may be allowed to operate on tokens without being their owner.
     */
    error ERC1155InvalidOperator(address operator);

    /**
     * @dev Indicates an array length mismatch between ids and values in a safeBatchTransferFrom operation.
     * Used in batch transfers.
     * @param idsLength Length of the array of token identifiers
     * @param valuesLength Length of the array of token amounts
     */
    error ERC1155InvalidArrayLength(uint256 idsLength, uint256 valuesLength);
}

pragma solidity >=0.5.0;

interface IUniswapV2Pair {
    event Approval(address indexed owner, address indexed spender, uint value);
    event Transfer(address indexed from, address indexed to, uint value);

    function name() external pure returns (string memory);
    function symbol() external pure returns (string memory);
    function decimals() external pure returns (uint8);
    function totalSupply() external view returns (uint);
    function balanceOf(address owner) external view returns (uint);
    function allowance(address owner, address spender) external view returns (uint);

    function approve(address spender, uint value) external returns (bool);
    function transfer(address to, uint value) external returns (bool);
    function transferFrom(address from, address to, uint value) external returns (bool);

    function DOMAIN_SEPARATOR() external view returns (bytes32);
    function PERMIT_TYPEHASH() external pure returns (bytes32);
    function nonces(address owner) external view returns (uint);

    function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external;

    event Mint(address indexed sender, uint amount0, uint amount1);
    event Burn(address indexed sender, uint amount0, uint amount1, address indexed to);
    event Swap(
        address indexed sender,
        uint amount0In,
        uint amount1In,
        uint amount0Out,
        uint amount1Out,
        address indexed to
    );
    event Sync(uint112 reserve0, uint112 reserve1);

    function MINIMUM_LIQUIDITY() external pure returns (uint);
    function factory() external view returns (address);
    function token0() external view returns (address);
    function token1() external view returns (address);
    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 mint(address to) external returns (uint liquidity);
    function burn(address to) external returns (uint amount0, uint amount1);
    function swap(uint amount0Out, uint amount1Out, address to, bytes calldata data) external;
    function skim(address to) external;
    function sync() external;

    function initialize(address, address) external;
}

pragma solidity >=0.5.0;

interface IUniswapV2Factory {
    event PairCreated(address indexed token0, address indexed token1, address pair, uint);

    function feeTo() external view returns (address);
    function feeToSetter() external view returns (address);

    function getPair(address tokenA, address tokenB) external view returns (address pair);
    function allPairs(uint) external view returns (address pair);
    function allPairsLength() external view returns (uint);

    function createPair(address tokenA, address tokenB) external returns (address pair);

    function setFeeTo(address) external;
    function setFeeToSetter(address) external;
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.0) (token/ERC20/extensions/IERC20Metadata.sol)

pragma solidity ^0.8.20;

import {IERC20} from "../IERC20.sol";

/**
 * @dev Interface for the optional metadata functions from the ERC20 standard.
 */
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);
}

pragma solidity >=0.6.2;

interface IUniswapV2Router01 {
    function factory() external pure returns (address);
    function WETH() external pure returns (address);

    function addLiquidity(
        address tokenA,
        address tokenB,
        uint amountADesired,
        uint amountBDesired,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline
    ) external returns (uint amountA, uint amountB, uint liquidity);
    function addLiquidityETH(
        address token,
        uint amountTokenDesired,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external payable returns (uint amountToken, uint amountETH, uint liquidity);
    function removeLiquidity(
        address tokenA,
        address tokenB,
        uint liquidity,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline
    ) external returns (uint amountA, uint amountB);
    function removeLiquidityETH(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external returns (uint amountToken, uint amountETH);
    function removeLiquidityWithPermit(
        address tokenA,
        address tokenB,
        uint liquidity,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountA, uint amountB);
    function removeLiquidityETHWithPermit(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountToken, uint amountETH);
    function swapExactTokensForTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external returns (uint[] memory amounts);
    function swapTokensForExactTokens(
        uint amountOut,
        uint amountInMax,
        address[] calldata path,
        address to,
        uint deadline
    ) external returns (uint[] memory amounts);
    function swapExactETHForTokens(uint amountOutMin, address[] calldata path, address to, uint deadline)
        external
        payable
        returns (uint[] memory amounts);
    function swapTokensForExactETH(uint amountOut, uint amountInMax, address[] calldata path, address to, uint deadline)
        external
        returns (uint[] memory amounts);
    function swapExactTokensForETH(uint amountIn, uint amountOutMin, address[] calldata path, address to, uint deadline)
        external
        returns (uint[] memory amounts);
    function swapETHForExactTokens(uint amountOut, address[] calldata path, address to, uint deadline)
        external
        payable
        returns (uint[] memory amounts);

    function quote(uint amountA, uint reserveA, uint reserveB) external pure returns (uint amountB);
    function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut) external pure returns (uint amountOut);
    function getAmountIn(uint amountOut, uint reserveIn, uint reserveOut) external pure returns (uint amountIn);
    function getAmountsOut(uint amountIn, address[] calldata path) external view returns (uint[] memory amounts);
    function getAmountsIn(uint amountOut, address[] calldata path) external view returns (uint[] memory amounts);
}

pragma solidity >=0.6.2;

import './IUniswapV2Router01.sol';

interface IUniswapV2Router02 is IUniswapV2Router01 {
    function removeLiquidityETHSupportingFeeOnTransferTokens(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external returns (uint amountETH);
    function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountETH);

    function swapExactTokensForTokensSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;
    function swapExactETHForTokensSupportingFeeOnTransferTokens(
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external payable;
    function swapExactTokensForETHSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;
}