contract Cosmos is ERC721, Ownable {
  using Strings for uint256;

  string public baseURI = "https://cosmickitchen.org/metas/";
  string public baseExtension = ".json";
  uint256 public cost = 0.075 ether;
  uint256 public maxSupply = 3018;
  uint256 public maxMintAmount = 10;
  uint256 public totalSupply =0 ; 
  bool public paused = false;

  constructor(
    string memory _name,
    string memory _symbol,
    string memory _initBaseURI
  ) ERC721(_name, _symbol) {
  setBaseURI(_initBaseURI);

  }

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

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

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

    for (uint256 i = 1; i <= _mintAmount; i++) {
      _safeMint(_to, supply + i);
      totalSupply=totalSupply+1;
    }
  }

  function tokensOfaddress(address _address)
    public
    view
    returns (uint256[] memory)
    
  {
    uint256 ownerTokenCount = balanceOf(_address);
    uint256[] memory tokenIds = new uint256[](ownerTokenCount);
    uint256 count=0;
    for (uint256 i=1;  i <= totalSupply && ownerTokenCount > count ; i++) {
        if(_exists(i)) {
            if(ownerOf(i)==_address){
            tokenIds[count]=i;
            count=count+1;
            }
        }
    }
    return tokenIds;
  }

  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(), baseExtension))
        : "";
  }

  //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 _newBaseExtension) public onlyOwner {
    baseExtension = _newBaseExtension;
  }

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

  function withdraw() public payable onlyOwner {
    require(payable(msg.sender).send(address(this).balance));
  }
}
function _baseURI() internal view virtual override returns (string memory) {
  return baseURI;
}

// internal