manifolds.sol

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.2;

import "@openzeppelin/contracts/token/ERC721/ERC721.sol";
import "@openzeppelin/contracts/token/ERC721/extensions/ERC721Enumerable.sol";
import "@openzeppelin/contracts/token/ERC721/extensions/ERC721Burnable.sol";
import "@openzeppelin/contracts/access/Ownable.sol";
import "@openzeppelin/contracts/utils/Counters.sol";

/// @custom:security-contact info@mcpcpc.com
contract Manifolds is ERC721, ERC721Enumerable, ERC721Burnable, Ownable {
    using Counters for Counters.Counter;

    Counters.Counter private _tokenIdCounter;
    uint256 public mintPrice = 0.05 ether;
    uint256 public maxSupply = 256;

    constructor() ERC721("Manifolds", "MANI") {}

    function _baseURI() internal pure override returns (string memory) {
        return "https://gateway.pinata.cloud/ipfs/QmeEKPwzQ3mCY8QWajcZnPKT4a6xJAEhLMppZKtaHhoQpY/";
    }

    function safeMint(address to) public payable {
        require(totalSupply() < maxSupply, "Mintable limit reached.");
        require(msg.value >= mintPrice, "Not enough ether sent.");
        _tokenIdCounter.increment();
        uint256 tokenId = _tokenIdCounter.current();
        _safeMint(to, tokenId);
    }
    
    function withdraw() public onlyOwner
    {
        require(address(this).balance > 0, "Balance is 0.");
        payable(owner()).transfer(address(this).balance);
    }
    
    function _beforeTokenTransfer(address from, address to, uint256 tokenId)
        internal
        override(ERC721, ERC721Enumerable)
    {
        super._beforeTokenTransfer(from, to, tokenId);
    }

    function supportsInterface(bytes4 interfaceId)
        public
        view
        override(ERC721, ERC721Enumerable)
        returns (bool)
    {
        return super.supportsInterface(interfaceId);
    }
}