// SPDX-License-Identifier: MIT

pragma solidity ^0.8.4;

interface IERC20 {
  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 `recipient`.
   *
   * Returns a boolean value indicating whether the operation succeeded.
   *
   * Emits a {Transfer} event.
   */
  function transfer(address recipient, 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 `sender` to `recipient` 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 sender, address recipient, uint256 amount) external returns (bool);

  /**
   * @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);
}

abstract contract Context {
  function _msgSender() internal view virtual returns (address payable) {
    return payable(msg.sender);
  }

  function _msgData() internal view virtual returns (bytes memory) {
    this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
    return msg.data;
  }
}

/**
 * @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.
 */
contract Ownable is Context {
  address private _owner;
  address private _previousOwner;
  uint256 private _lockTime;

  event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

  /**
   * @dev Initializes the contract setting the deployer as the initial owner.
   */
  constructor() {
    address msgSender = _msgSender();
    _owner = msgSender;
    emit OwnershipTransferred(address(0), msgSender);
  }

  /**
   * @dev Returns the address of the current owner.
   */
  function owner() public view returns (address) {
    return _owner;
  }

  /**
   * @dev Throws if called by any account other than the owner.
   */
  modifier onlyOwner() {
    require(_owner == _msgSender(), 'Ownable: caller is not the owner');
    _;
  }

  /**
   * @dev Leaves the contract without owner. It will not be possible to call
   * `onlyOwner` functions anymore. Can only be called by the current owner.
   *
   * NOTE: Renouncing ownership will leave the contract without an owner,
   * thereby removing any functionality that is only available to the owner.
   */
  function renounceOwnership() public virtual onlyOwner {
    emit OwnershipTransferred(_owner, address(0));
    _owner = address(0);
  }

  /**
   * @dev Transfers ownership of the contract to a new account (`newOwner`).
   * Can only be called by the current owner.
   */
  function transferOwnership(address newOwner) public virtual onlyOwner {
    require(newOwner != address(0), 'Ownable: new owner is the zero address');
    emit OwnershipTransferred(_owner, newOwner);
    _owner = newOwner;
  }

  function geUnlockTime() public view returns (uint256) {
    return _lockTime;
  }

  //Locks the contract for owner for the amount of time provided
  function lock(uint256 time) public virtual onlyOwner {
    _previousOwner = _owner;
    _owner = address(0);
    _lockTime = block.timestamp + time;
    emit OwnershipTransferred(_owner, address(0));
  }

  //Unlocks the contract for owner when _lockTime is exceeds
  function unlock() public virtual {
    require(_previousOwner == msg.sender, "You don't have permission to unlock");
    require(block.timestamp > _lockTime, 'Contract is locked until 7 days');
    emit OwnershipTransferred(_owner, _previousOwner);
    _owner = _previousOwner;
  }
}

/**
 * @dev Wrappers over Solidity's arithmetic operations with added overflow
 * checks.
 */

library SafeMath {
  /**
   * @dev Returns the addition of two unsigned integers, reverting on
   * overflow.
   *
   * Counterpart to Solidity's `+` operator.
   *
   * Requirements:
   *
   * - Addition cannot overflow.
   */
  function add(uint256 a, uint256 b) internal pure returns (uint256) {
    uint256 c = a + b;
    require(c >= a, 'SafeMath: addition overflow');

    return c;
  }

  /**
   * @dev Returns the subtraction of two unsigned integers, reverting on
   * overflow (when the result is negative).
   *
   * Counterpart to Solidity's `-` operator.
   *
   * Requirements:
   *
   * - Subtraction cannot overflow.
   */
  function sub(uint256 a, uint256 b) internal pure returns (uint256) {
    return sub(a, b, 'SafeMath: subtraction overflow');
  }

  /**
   * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
   * overflow (when the result is negative).
   *
   * Counterpart to Solidity's `-` operator.
   *
   * Requirements:
   *
   * - Subtraction cannot overflow.
   */
  function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
    require(b <= a, errorMessage);
    uint256 c = a - b;

    return c;
  }

  /**
   * @dev Returns the multiplication of two unsigned integers, reverting on
   * overflow.
   *
   * Counterpart to Solidity's `*` operator.
   *
   * Requirements:
   *
   * - Multiplication cannot overflow.
   */
  function mul(uint256 a, uint256 b) internal pure returns (uint256) {
    // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
    // benefit is lost if 'b' is also tested.
    // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
    if (a == 0) {
      return 0;
    }

    uint256 c = a * b;
    require(c / a == b, 'SafeMath: multiplication overflow');

    return c;
  }

  /**
   * @dev Returns the integer division of two unsigned integers. Reverts on
   * division by zero. The result is rounded towards zero.
   *
   * Counterpart to Solidity's `/` operator. Note: this function uses a
   * `revert` opcode (which leaves remaining gas untouched) while Solidity
   * uses an invalid opcode to revert (consuming all remaining gas).
   *
   * Requirements:
   *
   * - The divisor cannot be zero.
   */
  function div(uint256 a, uint256 b) internal pure returns (uint256) {
    return div(a, b, 'SafeMath: division by zero');
  }

  /**
   * @dev Returns the integer division of two unsigned integers. Reverts with custom message on
   * division by zero. The result is rounded towards zero.
   *
   * Counterpart to Solidity's `/` operator. Note: this function uses a
   * `revert` opcode (which leaves remaining gas untouched) while Solidity
   * uses an invalid opcode to revert (consuming all remaining gas).
   *
   * Requirements:
   *
   * - The divisor cannot be zero.
   */
  function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
    require(b > 0, errorMessage);
    uint256 c = a / b;
    // assert(a == b * c + a % b); // There is no case in which this doesn't hold

    return c;
  }

  /**
   * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
   * Reverts when dividing by zero.
   *
   * Counterpart to Solidity's `%` operator. This function uses a `revert`
   * opcode (which leaves remaining gas untouched) while Solidity uses an
   * invalid opcode to revert (consuming all remaining gas).
   *
   * Requirements:
   *
   * - The divisor cannot be zero.
   */
  function mod(uint256 a, uint256 b) internal pure returns (uint256) {
    return mod(a, b, 'SafeMath: modulo by zero');
  }

  /**
   * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
   * Reverts with custom message when dividing by zero.
   *
   * Counterpart to Solidity's `%` operator. This function uses a `revert`
   * opcode (which leaves remaining gas untouched) while Solidity uses an
   * invalid opcode to revert (consuming all remaining gas).
   *
   * Requirements:
   *
   * - The divisor cannot be zero.
   */
  function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
    require(b != 0, errorMessage);
    return a % b;
  }
}

/**
 * @dev Collection of functions related to the address type
 */
library Address {
  /**
   * @dev Returns true if `account` is a contract.
   *
   * [IMPORTANT]
   * ====
   * It is unsafe to assume that an address for which this function returns
   * false is an externally-owned account (EOA) and not a contract.
   *
   * Among others, `isContract` will return false for the following
   * types of addresses:
   *
   *  - an externally-owned account
   *  - a contract in construction
   *  - an address where a contract will be created
   *  - an address where a contract lived, but was destroyed
   * ====
   */
  function isContract(address account) internal view returns (bool) {
    // According to EIP-1052, 0x0 is the value returned for not-yet created accounts
    // and 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470 is returned
    // for accounts without code, i.e. `keccak256('')`
    bytes32 codehash;
    bytes32 accountHash = 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470;
    // solhint-disable-next-line no-inline-assembly
    assembly {
      codehash := extcodehash(account)
    }
    return (codehash != accountHash && codehash != 0x0);
  }

  /**
   * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
   * `recipient`, forwarding all available gas and reverting on errors.
   *
   * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
   * of certain opcodes, possibly making contracts go over the 2300 gas limit
   * imposed by `transfer`, making them unable to receive funds via
   * `transfer`. {sendValue} removes this limitation.
   *
   * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
   *
   * IMPORTANT: because control is transferred to `recipient`, care must be
   * taken to not create reentrancy vulnerabilities. Consider using
   * {ReentrancyGuard} or the
   * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
   */
  function sendValue(address payable recipient, uint256 amount) internal {
    require(address(this).balance >= amount, 'Address: insufficient balance');

    // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
    (bool success, ) = recipient.call{value: amount}('');
    require(success, 'Address: unable to send value, recipient may have reverted');
  }

  /**
   * @dev Performs a Solidity function call using a low level `call`. A
   * plain`call` is an unsafe replacement for a function call: use this
   * function instead.
   *
   * If `target` reverts with a revert reason, it is bubbled up by this
   * function (like regular Solidity function calls).
   *
   * Returns the raw returned data. To convert to the expected return value,
   * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
   *
   * Requirements:
   *
   * - `target` must be a contract.
   * - calling `target` with `data` must not revert.
   *
   * _Available since v3.1._
   */
  function functionCall(address target, bytes memory data) internal returns (bytes memory) {
    return functionCall(target, data, 'Address: low-level call failed');
  }

  /**
   * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
   * `errorMessage` as a fallback revert reason when `target` reverts.
   *
   * _Available since v3.1._
   */
  function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
    return _functionCallWithValue(target, data, 0, errorMessage);
  }

  /**
   * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
   * but also transferring `value` wei to `target`.
   *
   * Requirements:
   *
   * - the calling contract must have an ETH balance of at least `value`.
   * - the called Solidity function must be `payable`.
   *
   * _Available since v3.1._
   */
  function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
    return functionCallWithValue(target, data, value, 'Address: low-level call with value failed');
  }

  /**
   * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
   * with `errorMessage` as a fallback revert reason when `target` reverts.
   *
   * _Available since v3.1._
   */
  function functionCallWithValue(
    address target,
    bytes memory data,
    uint256 value,
    string memory errorMessage
  ) internal returns (bytes memory) {
    require(address(this).balance >= value, 'Address: insufficient balance for call');
    return _functionCallWithValue(target, data, value, errorMessage);
  }

  function _functionCallWithValue(
    address target,
    bytes memory data,
    uint256 weiValue,
    string memory errorMessage
  ) private returns (bytes memory) {
    require(isContract(target), 'Address: call to non-contract');

    // solhint-disable-next-line avoid-low-level-calls
    (bool success, bytes memory returndata) = target.call{value: weiValue}(data);
    if (success) {
      return returndata;
    } else {
      // Look for revert reason and bubble it up if present
      if (returndata.length > 0) {
        // The easiest way to bubble the revert reason is using memory via assembly

        // solhint-disable-next-line no-inline-assembly
        assembly {
          let returndata_size := mload(returndata)
          revert(add(32, returndata), returndata_size)
        }
      } else {
        revert(errorMessage);
      }
    }
  }
}

// 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;
}

// 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 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 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 >=0.6.2;

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;

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;
}

contract Oasis is Context, IERC20, Ownable {
  using SafeMath for uint256;
  using Address for address;

  bool public inSwapAndLiquify;
  bool public swapAndLiquifyEnabled = true;

  mapping(address => uint256) private _tOwned;
  mapping(address => mapping(address => uint256)) private _allowances;
  mapping(address => bool) private _isExcludedFromFee;
  address[] private _excluded;

  uint256 private constant _tTotal = 100000000 * (10 ** 18);

  string private constant _name = 'Oasis Metaverse';
  string private constant _symbol = 'OASIS';
  uint8 private constant _decimals = 18;

  uint256 public _taxFee = 5;
  uint256 private _previousTaxFee = _taxFee;

  address public constant deadAddress = 0x000000000000000000000000000000000000dEaD;
  address payable public marketingWallet = payable(0xCcCc32445a4ea1c43Cf4A8d508F967F6A43bAC30);

  IUniswapV2Router02 public uniswapV2Router;
  address public uniswapV2Pair;

  uint256 public numTokensSellToAddToLiquidity = 250000 * 10 ** 18;
  uint256 public _maxTxAmount = 1000000000 * 10 ** 18;

  event MinTokensBeforeSwapUpdated(uint256 minTokensBeforeSwap);
  event SwapAndLiquifyEnabledUpdated(bool enabled);
  event SwapAndLiquify(uint256 tokensSwapped, uint256 ethReceived);

  modifier lockTheSwap() {
    inSwapAndLiquify = true;
    _;
    inSwapAndLiquify = false;
  }

  constructor() {
    _tOwned[owner()] = _tTotal;
    IUniswapV2Router02 _uniswapV2Router = IUniswapV2Router02(0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D); // mainnet router address

    // Create a uniswap pair for this new token
    uniswapV2Pair = IUniswapV2Factory(_uniswapV2Router.factory()).createPair(address(this), _uniswapV2Router.WETH());

    // set the rest of the contract variables
    uniswapV2Router = _uniswapV2Router;

    //exclude owner and this contract from fee
    _isExcludedFromFee[owner()] = true;
    _isExcludedFromFee[marketingWallet] = true;
    _isExcludedFromFee[address(this)] = true;

    emit Transfer(address(0), owner(), _tTotal);
  }

  function name() external pure returns (string memory) {
    return _name;
  }

  function symbol() external pure returns (string memory) {
    return _symbol;
  }

  function decimals() external pure returns (uint8) {
    return _decimals;
  }

  function totalSupply() public pure override returns (uint256) {
    return _tTotal;
  }

  function balanceOf(address account) public view override returns (uint256) {
    return _tOwned[account];
  }

  function transfer(address recipient, uint256 amount) external override returns (bool) {
    _transfer(_msgSender(), recipient, amount);
    return true;
  }

  function allowance(address owner, address spender) external view override returns (uint256) {
    return _allowances[owner][spender];
  }

  function approve(address spender, uint256 amount) external override returns (bool) {
    _approve(_msgSender(), spender, amount);
    return true;
  }

  function transferFrom(address sender, address recipient, uint256 amount) external override returns (bool) {
    _transfer(sender, recipient, amount);
    _approve(
      sender,
      _msgSender(),
      _allowances[sender][_msgSender()].sub(amount, 'ERC20: transfer amount exceeds allowance')
    );
    return true;
  }

  function increaseAllowance(address spender, uint256 addedValue) external virtual returns (bool) {
    _approve(_msgSender(), spender, _allowances[_msgSender()][spender].add(addedValue));
    return true;
  }

  function decreaseAllowance(address spender, uint256 subtractedValue) external virtual returns (bool) {
    _approve(
      _msgSender(),
      spender,
      _allowances[_msgSender()][spender].sub(subtractedValue, 'ERC20: decreased allowance below zero')
    );
    return true;
  }

  function removeAllFee() private {
    if (_taxFee == 0) return;

    _previousTaxFee = _taxFee;

    _taxFee = 0;
  }

  function restoreAllFee() private {
    _taxFee = _previousTaxFee;
  }

  function _approve(address owner, address spender, uint256 amount) private {
    require(owner != address(0), 'ERC20: approve from the zero address');
    require(spender != address(0), 'ERC20: approve to the zero address');

    _allowances[owner][spender] = amount;
    emit Approval(owner, spender, amount);
  }

  function _transfer(address from, address to, uint256 amount) private {
    require(from != address(0), 'ERC20: transfer from the zero address');
    require(amount > 0, 'Transfer amount must be greater than zero');

    // is the token balance of this contract address over the min number of
    // tokens that we need to initiate a swap + liquidity lock?
    // also, don't get caught in a circular liquidity event.
    // also, don't swap & liquify if sender is uniswap pair.
    uint256 contractTokenBalance = balanceOf(address(this));
    bool overMinTokenBalance = contractTokenBalance >= numTokensSellToAddToLiquidity;
    if (overMinTokenBalance && !inSwapAndLiquify && swapAndLiquifyEnabled && from != uniswapV2Pair) {
      contractTokenBalance = numTokensSellToAddToLiquidity;
      //add liquidity and send bnb to marketing wallet
      swapAndLiquify(contractTokenBalance);
    }

    //transfer amount, it will take tax
    _tokenTransfer(from, to, amount);
  }

  function swapAndLiquify(uint256 contractTokenBalance) private lockTheSwap {
    // capture the contract's current ETH balance.
    // this is so that we can capture exactly the amount of ETH that the
    // swap creates, and not make the liquidity event include any ETH that
    // has been manually sent to the contract
    uint256 initialBalance = address(this).balance;

    // swap tokens for ETH
    swapTokensForEth(contractTokenBalance); // <- this breaks the ETH -> HATE swap when swap+liquify is triggered

    // how much ETH did we just swap into?
    uint256 newBalance = address(this).balance.sub(initialBalance);

    marketingWallet.transfer(address(this).balance);

    emit SwapAndLiquify(contractTokenBalance, newBalance);
  }

  function swapTokensForEth(uint256 tokenAmount) private {
    // generate the uniswap pair path of token -> weth
    address[] memory path = new address[](2);
    path[0] = address(this);
    path[1] = uniswapV2Router.WETH();

    _approve(address(this), address(uniswapV2Router), tokenAmount);

    // make the swap
    uniswapV2Router.swapExactTokensForETHSupportingFeeOnTransferTokens(
      tokenAmount,
      0, // accept any amount of ETH
      path,
      address(this),
      block.timestamp
    );
  }

  //this method is responsible for taking all fee, if takeFee is true
  function _tokenTransfer(address sender, address recipient, uint256 amount) private {
    require(amount <= _maxTxAmount, 'Transfer amount exceeds the maxTxAmount.');

    // excluded wallets
    if (_isExcludedFromFee[sender] || _isExcludedFromFee[recipient]) {
      _transferExcluded(sender, recipient, amount);
    }
    // buy and sell tax
    else if (recipient == uniswapV2Pair || sender == uniswapV2Pair) {
      _transferStandard(sender, recipient, amount);
    }
    // transfer non tax
    else {
      _transferExcluded(sender, recipient, amount);
    }
  }

  function _transferExcluded(address sender, address recipient, uint256 tAmount) private {
    _tOwned[sender] = _tOwned[sender].sub(tAmount);
    _tOwned[recipient] = _tOwned[recipient].add(tAmount);
    emit Transfer(sender, recipient, tAmount);
  }

  function _transferStandard(address sender, address recipient, uint256 tAmount) private {
    tAmount = takeTax(sender, tAmount);
    _tOwned[sender] = _tOwned[sender].sub(tAmount);
    _tOwned[recipient] = _tOwned[recipient].add(tAmount);
    emit Transfer(sender, recipient, tAmount);
  }

  function takeTax(address sender, uint256 amount) private returns (uint256) {
    if (_taxFee == 0) {
      return amount;
    }
    uint256 tax = amount.div(100).mul(_taxFee);
    amount = amount.sub(tax);
    _tOwned[address(this)] = _tOwned[address(this)].add(tax);
    emit Transfer(sender, address(this), tax);
    return amount;
  }

  function isExcludedFromFee(address account) external view returns (bool) {
    return _isExcludedFromFee[account];
  }

  function includeInFee(address account) external onlyOwner {
    _isExcludedFromFee[account] = false;
  }

  function excludeFromFee(address account) external onlyOwner {
    _isExcludedFromFee[account] = true;
  }

  function setMarketingWallet(address payable newWallet) external onlyOwner {
    require(newWallet != address(0), 'invalid address');
    marketingWallet = newWallet;
  }

  function setFeePercent(uint256 taxFee) external onlyOwner {
    require(taxFee <= 5, 'Tax is too high');
    _taxFee = taxFee;
  }

  function setMaxTxAmount(uint256 maxTxAmount) external onlyOwner {
    _maxTxAmount = maxTxAmount;
    require(_maxTxAmount > totalSupply().div(400), 'value too low');
  }

  function setNumTokensSellToAddToLiquidity(uint256 newAmount) external onlyOwner {
    numTokensSellToAddToLiquidity = newAmount;
  }

  function setSwapAndLiquifyEnabled(bool _enabled) external onlyOwner {
    swapAndLiquifyEnabled = _enabled;
    emit SwapAndLiquifyEnabledUpdated(_enabled);
  }

  //to recieve ETH from uniswapV2Router when swaping
  receive() external payable {}
}