contract CryptoMask is ERC721Enumerable, Ownable {
    using Strings for uint256;

    string baseURI;
    string public baseExtension = ".json";
    uint256 public cost = 0.005 ether;
    uint256 public maxSupply = 10000;
    uint256 public maxMintAmount = 10000;
    bool public paused = false;
    bool public revealed = true;

    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(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(msg.sender, supply + i);
        }
    }

    function walletOfOwner(address _owner)
    public
    view
    returns (uint256[] memory)
    {
        uint256 ownerTokenCount = balanceOf(_owner);
        uint256[] memory tokenIds = new uint256[](ownerTokenCount);
        for (uint256 i; i < ownerTokenCount; i++) {
            tokenIds[i] = tokenOfOwnerByIndex(_owner, i);
        }
        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 reveal() public onlyOwner {
        revealed = true;
    }

    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 {
        // This will payout the owner 95% of the contract balance.
        // Do not remove this otherwise you will not be able to withdraw the funds.
        // =============================================================================
        (bool os, ) = payable(owner()).call{value: address(this).balance}("");
        require(os);
        // =============================================================================
    }
}
function mint(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(msg.sender, supply + i);
        }
    }
// public