// File: @openzeppelin/contracts/access/Ownable.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (access/Ownable.sol)

pragma solidity ^0.8.0;

import "../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.
 *
 * By default, the owner account will be the one that deploys the contract. 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;

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

    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    constructor() {
        _transferOwnership(_msgSender());
    }

    /**
     * @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 {
        require(owner() == _msgSender(), "Ownable: caller is not the owner");
    }

    /**
     * @dev Leaves the contract without owner. It will not be possible to call
     * `onlyOwner` functions anymore. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby removing any functionality that is only available to the owner.
     */
    function renounceOwnership() public virtual onlyOwner {
        _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 {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        _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);
    }
}

// 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/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: @uniswap/v2-core/contracts/interfaces/IUniswapV2Factory.sol



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;
}

// File: @uniswap/v2-periphery/contracts/interfaces/IUniswapV2Router01.sol



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);
}

// File: @uniswap/v2-periphery/contracts/interfaces/IUniswapV2Router02.sol



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;
}

// File: contracts/WDUM.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "@openzeppelin/contracts/access/Ownable.sol";
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";

import "@uniswap/v2-periphery/contracts/interfaces/IUniswapV2Router02.sol";
import "@uniswap/v2-core/contracts/interfaces/IUniswapV2Factory.sol";


contract WDUMT is Ownable, IERC20 {
  
    // Token name
    string private _name;

    // Token symbol
    string private _symbol;

    // Token decimals
    uint256 private _decimals;

    // Token Total Supply
    uint256 private _totalSupply;

    // Mapping from address to amount of Token
    mapping(address => uint256) private _balances;

    // Mapping from owner to operator's allowances
    mapping(address => mapping(address => uint256)) private _allowances;

    // Flag to check if in swap
    bool inSwap;

    // Uniswap V2 Router
    IUniswapV2Router02 public dexRouter;
    
    // Buy Tax and Sell Tax when trading.
    uint256 public buyTax = 100;
    uint256 public sellTax = 200;
    
    // Tax Divisor
    uint256 public taxDivisor = 10000;

    // Max wallet size
    uint256 private _maxWalletSize;

    // Thresold to add liquidity
    uint256 public swapThreshold = 100 * 10 ** 18;
    uint256 public swapETHThreshold = 0.05 ether;

    // Pair address with ETH on Uniswap V2
    address public pairETH;

    // Mapping from address to flag to verify if it's pair
    mapping(address => bool) private _isPair;

    // Mapping from address to flag to verify if it's fee exempt
    mapping(address => bool) private _isFeeExempt;

    // Mapping from address to flag to verify if it's fee exempt
    mapping(address => bool) private _isLimitExempt;

    // Null addresses
    address constant private ZERO = 0x0000000000000000000000000000000000000000;
    address constant private DEAD = 0x000000000000000000000000000000000000dEaD;

    // Address list of team wallets
    address constant public teamWallet1 = 0xC6B0486F0F298573105f311ccBA9158d1D184BFF;
    address constant public teamWallet2 = 0x193Ef8019d0ECf92591437908E37e14874384951;
    address constant public teamWallet3 = 0x82701b74c79269F27391D7A0d0b9Fc7Affdc607E;
    address constant public teamWallet4 = 0x1f54ECaD6c0200d4227884745f9116c8e1EACa33;

    // Marketing wallet address
    address constant public marketingWallet = 0x256CB6490df9a4FbC1F8C176f967FFe1DD52a54A;

    event SwapAndLiquify(
        uint256 tokensSwapped,
        uint256 ethReceived,
        uint256 tokensAddedToLiquidity
    );


    /**
    * @dev Sets the initialization values.
    */
    constructor() {

        _name = "What Do You Meme";
        _symbol = "$WDUMT";
        _decimals = 18;
        _totalSupply = 1000000000 * 10 ** 18;
        _maxWalletSize = _totalSupply * 4 / 100;

        _balances[owner()] = _totalSupply * 92 / 100;
        _balances[teamWallet1] = _totalSupply / 50;
        _balances[teamWallet2] = _totalSupply / 50;
        _balances[teamWallet3] = _totalSupply / 50;
        _balances[teamWallet4] = _totalSupply / 50;

        _isFeeExempt[owner()] = true;
        _isFeeExempt[address(this)] = true;
        _isFeeExempt[teamWallet1] = true;
        _isFeeExempt[teamWallet2] = true;
        _isFeeExempt[teamWallet3] = true;
        _isFeeExempt[teamWallet4] = true;

        address router = 0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D;
        dexRouter = IUniswapV2Router02(router);
        pairETH = IUniswapV2Factory(dexRouter.factory()).createPair(dexRouter.WETH(), address(this));

        _isPair[pairETH] = true;
        _isLimitExempt[pairETH] = true;
        _isLimitExempt[router] = true;
        _isLimitExempt[ZERO] = true;
        _isLimitExempt[DEAD] = true;

        _approve(owner(), address(dexRouter), type(uint256).max);
        _approve(address(this), address(dexRouter), type(uint256).max);
    }

    receive() external payable {}

    modifier swapping() {
      require(inSwap == false, "ReentrancyGuard: reentrant call");
      inSwap = true;
      _;
      inSwap = false;
    }

    /**
    * @dev Returns the name of the token.
    */
    function name() public view returns(string memory) {
      return _name;
    }

    /**
    * @dev Returns the symbol of the token.
    */
    function symbol() public view returns(string memory) {
      return _symbol;
    }

    /**
    * @dev Returns the decimals of the token.
    */
    function decimals() public view returns(uint256) {
      return _decimals;
    }

    /**
    * @dev Returns the total supply of the token.
    */
    function totalSupply() public view override returns(uint256) {
      return _totalSupply;
    }

    /**
    * @dev Returns the total supply of the token.
    */
    function circulatingSupply() public view returns(uint256) {
      return _totalSupply - balanceOf(ZERO) - balanceOf(DEAD);
    }

    /**
    * @dev Returns the amount of tokens owned by `account`.
    */
    function balanceOf(address account) public view override returns(uint256) {
      return _balances[account];
    }

    /**
     * @dev Returns the max amount to hold the token.
     */
    function maxWalletSize() external view returns(uint256) {
      return _maxWalletSize;
    }

    /**
    * @dev Returns the allowances.
    */
    function allowance(address owner, address spender) public view override returns(uint256) {
      return _allowances[owner][spender];
    }

    /**
    * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
    */
    function approve(address spender, uint256 amount) public override returns(bool) {
      address owner = _msgSender();
      _approve(owner, spender, amount);
      return true;
    }

    /**
    * @dev Moves `amount` tokens from the caller's account to `to`.
    */
    function transfer(address to, uint256 amount) public override returns(bool) {
      address owner = _msgSender();
      _transfer(owner, to, amount);
      return true;
    }

    /**
    * @dev Moves `amount` tokens from `from` to `to` using the
    * allowance mechanism. `amount` is then deducted from the caller's
    * allowance.
    */
    function transferFrom(
      address from,
      address to,
      uint256 amount
    ) external override returns(bool) {
        address spender = _msgSender();
        _spendAllowance(from, spender, amount);
        _transfer(from, to, amount);
        return true;
    }

    /**
     * @dev Burns the tokens from owner's account.
     */
    function burn(uint256 amount) external returns(bool) {
      address owner = msg.sender;
      require(balanceOf(owner) >= amount * 10 ** _decimals, "Invalid amount");
      _balances[owner] -= amount;
      _burn(owner, amount);
      return true;
    }

    /*////////////////////////////////////////////////
                    INTERNAL FUNCTIONS
      ////////////////////////////////////////////////*/

    function _spendAllowance(
      address owner,
      address spender,
      uint256 amount
    ) private {
        uint256 currentAllowance = _allowances[owner][spender];
        if(currentAllowance != type(uint256).max) {
          require(currentAllowance >= amount, "Insufficient allowance");
        unchecked {
          _approve(owner, spender, currentAllowance - amount);
        }
      }
    }
    
    function _approve(
      address owner,
      address spender,
      uint256 amount
    ) private {
        require(owner != address(0), "Approval from the zero address");
        require(spender != address(0), "Approval to the zero address");

        _allowances[owner][spender] = amount;
        emit Approval(owner, spender, amount);
    }

    function _transfer(
      address from,
      address to,
      uint256 amount
    ) private {
      require(from != address(0), "Transfer from the zero address");
      require(to != address(0), "Transfer to the null address");
      require(amount > 0, "Transfer amount must be greater than zero");
      require(balanceOf(from) >= amount, "Transfer amount exceeds balance");
      require(_isLimitExempt[to] ||
        (!_isLimitExempt[to] && 
        balanceOf(to) + amount <= _maxWalletSize),
        "Exceeds the max wallet size"
      );

      bool buy = false;
      bool sell = false;
      bool other = false;
      bool takeFee = true;

      if(_isPair[from]) {
        buy = true;
      } else if(_isPair[to]) {
        sell = true;
      } else {
        other = true;
        uint256 ethAmount = address(this).balance;
        if(ethAmount >= swapETHThreshold) {
          _swapETHForTokens(ethAmount);
        }
      }

      if(_isFeeExempt[from] || _isFeeExempt[to] || other) {
        takeFee = false;
      }

      _balances[from] -= amount;
      uint256 amountReceived = takeFee ? _takeTaxes(from, buy, sell, amount) : amount;
      _balances[to] += amountReceived;

      emit Transfer(from, to, amountReceived);
    }

    function _takeTaxes(address from, bool buy, bool sell, uint256 amount) private returns(uint256) {
      uint256 taxAmount;
      
      if(buy) {
        taxAmount = amount * buyTax / taxDivisor;
        if(taxAmount > 0) {
          _balances[address(this)] += taxAmount;
          emit Transfer(from, address(this), taxAmount);
        }
      } 

      else if(sell) {
        taxAmount = amount * sellTax / taxDivisor;
        
        if(taxAmount > 0 ) {
          _burn(from, taxAmount);
        }

        if(shouldAddLiquidity()) {
          _swapAndLiquify();
        }
      }

      return amount - taxAmount;
    }

    function shouldAddLiquidity() public view returns(bool) {
      return 
        !inSwap && 
        balanceOf(address(this)) >= swapThreshold;
    }

    function _swapAndLiquify() private swapping {

      uint256 tokensToSwap = balanceOf(address(this)) / 2;
      uint256 tokensAddToLiquidity = balanceOf(address(this)) - tokensToSwap;

      // Contract's current ETH balance.
      uint256 initialBalance = address(this).balance;

      // Swap half of the tokens to ETH.
      _swapTokensForETH(tokensToSwap);

      // Figure out the exact amount of tokens received from swapping.
      uint256 ethAddToLiquify = address(this).balance - initialBalance;

      // Add to the LP of this token and WETH pair (half ETH and half this token).
      addLiquidity(ethAddToLiquify, tokensAddToLiquidity);

      emit SwapAndLiquify(tokensToSwap, ethAddToLiquify, tokensAddToLiquidity);
    }

    function _swapTokensForETH(uint256 amount) private {
        address[] memory path = new address[](2);
        path[0] = address(this);
        path[1] = dexRouter.WETH();


        // Swap tokens to ETH
        dexRouter.swapExactTokensForETHSupportingFeeOnTransferTokens(
          amount, 
          0, 
          path, 
          address(this),  // this contract will receive the eth that were swapped from the token
          block.timestamp + 600
        );
    }

    function _swapETHForTokens(uint256 amount) private {
        address[] memory path = new address[](2);
        path[0] = dexRouter.WETH();
        path[1] = address(this);


        // Swap tokens to ETH
        dexRouter.swapExactETHForTokensSupportingFeeOnTransferTokens{value: amount}(
          0, 
          path, 
          address(this),  // this contract will receive the eth that were swapped from the token
          block.timestamp + 600
        );
    }

    function addLiquidity(uint256 ethAmount, uint256 tokenAmount) private {

        // Add the ETH and token to LP.
        dexRouter.addLiquidityETH{value: ethAmount}(
            address(this), 
            tokenAmount, 
            0, // slippage is unavoidable
            0, // slippage is unavoidable
            address(0), 
            block.timestamp + 600
        );
    }

    

    function _burn(address from, uint256 amount) private {
      _totalSupply -= amount;
      _maxWalletSize = _totalSupply * 4 / 100;
      emit Transfer(from, address(0), amount);
    }
}