contract InvsbleFrens is ERC721A, Ownable {
  using Strings for uint256;

  string public baseURI;
  string public baseExtenstion = ".json";
  uint256 public cost = 0.01 ether;
  uint256 public maxSupply = 5000;
  uint256 maxMintAmount = 25;
  bool public paused = true;

  constructor(
    string memory _name,
    string memory _symbol,
    string memory _initBaseURI
  ) ERC721A(_name, _symbol) {
    setBaseURI(_initBaseURI);
  }

  function _baseURI() internal view virtual override returns (string memory) {
    return baseURI;
  }

  function mint(address _to, uint256 _mintAmount) public payable {
    uint256 supply = totalSupply();
    require(!paused);
    require(_mintAmount > 0);
    require(_mintAmount <= maxMintAmount);
    require(supply + _mintAmount <= maxSupply);
    require(_mintAmount <= maxMintAmount);

    if (msg.sender != owner()) {
      require(msg.value >= cost * _mintAmount);
    }

    _safeMint(_to, _mintAmount);

  }


  function tokenURI(uint256 tokenId)
    public
    view
    virtual
    override
    returns (string memory)
  {
    require(
      _exists(tokenId),
      "ERC721Metadata: URI query for nonexistent token"
    );

    string memory currentBaseURI = _baseURI();
    return
      bytes(currentBaseURI).length > 0
        ? string(
          abi.encodePacked(currentBaseURI, tokenId.toString(), baseExtenstion)
        )
        : "";
  }

  //only owner
  function setCost(uint256 _newCost) public onlyOwner {
    cost = _newCost;
  }

  function setmaxMintAmount(uint256 _newmaxMintAmount) public onlyOwner {
    maxMintAmount = _newmaxMintAmount;
  }

  function setBaseURI(string memory _newBaseURI) public onlyOwner {
    baseURI = _newBaseURI;
  }

  function SetBaseExtension(string memory _newBaseExtestion) public onlyOwner {
    baseExtenstion = _newBaseExtestion;
  }

  function pause(bool _state) public onlyOwner {
    paused = _state;
  }

  function withdraw() public payable onlyOwner {
    require(payable(msg.sender).send(address(this).balance));
  }
}
function setCost(uint256 _newCost) public onlyOwner {
  cost = _newCost;
}

//only owner