task3: Georgiafab

members/Georgiafab/task3/ERC20Token.sol

@@ -0,0 +1,9 @@
+// SPDX-License-Identifier: MIT
+pragma solidity >=0.8.2 <0.9.0;
+
+import "@openzeppelin/contracts/token/ERC20/ERC20.sol";
+contract MTK is ERC20 {
+    constructor(address owner) ERC20("MILKToken", "MTK") {
+        _mint(owner, 21000000 * 10 ** 18);
+    }
+}

members/Georgiafab/task3/ERC721Token.sol

@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: MIT
+pragma solidity >=0.8.2 <0.9.0;
+
+import "@openzeppelin/contracts/token/ERC721/ERC721.sol";
+
+contract MILKNT is ERC721 {
+    uint256 private _nextId;
+
+    constructor() ERC721("MILKNFT", "MILKNT") {}
+
+    function saftMint(address to) public {
+        uint256 tokenId = _nextId++;
+        _safeMint(to, tokenId);
+    }
+}

members/Georgiafab/task3/NFTMarket.sol

@@ -0,0 +1,167 @@
+// SPDX-License-Identifier: GPL-3.0
+
+pragma solidity >=0.8.2 <0.9.0;
+import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
+import "@openzeppelin/contracts/token/ERC721/IERC721.sol";
+import "@openzeppelin/contracts/utils/ReentrancyGuard.sol";
+import "@openzeppelin/contracts/utils/math/Math.sol";
+
+contract NFTMarket is ReentrancyGuard {
+    IERC20 public tokenContract;
+    using Math for uint256;
+
+    struct Listing {
+        uint256 tokenId; // NFT的Token ID
+        address seller; // 上架者地址
+        address nftContract; // NFT 合约地址
+        uint256 price; // 上架价格（使用ERC20代币）
+        bool active; // 上架状态
+    }
+
+    // 存储所有上架的NFT信息
+    mapping(address => mapping(uint256 => Listing)) public listings;
+
+    // 记录所有有上架NFT的合约地址
+    address[] private nftContracts;
+    // 记录每个合约地址对应的tokenId数组
+    mapping(address => uint256[]) private nftTokenIds;
+
+    // 上架NFT事件
+    event NFTListed(
+        uint256 indexed tokenId,
+        address indexed seller,
+        address indexed nftContract,
+        uint256 price
+    );
+
+    // 下架NFT事件
+    event NFTUnListed(uint256 indexed tokenId, address indexed seller);
+
+    // 购买NFT事件
+    event NFTSold(
+        uint256 tokenId,
+        address indexed buyer,
+        address indexed seller,
+        address nftContract,
+        uint256 price
+    );
+
+    // 合约构造函数，初始化ERC20代币合约地址
+    constructor(address _tokenContractAddress) {
+        tokenContract = IERC20(_tokenContractAddress);
+    }
+
+    function getTokenContract() external view returns (IERC20) {
+        return tokenContract;
+    }
+
+    // 上架NFT
+    function listNFT(
+        address _nftContract,
+        uint256 _tokenId,
+        uint256 _price
+    ) external {
+        // 确保上架者是NFT的所有者
+        IERC721 nftContract = IERC721(_nftContract);
+        require(nftContract.ownerOf(_tokenId) == msg.sender, "Not token owner");
+        // 确保上架价格大于零
+        require(_price > 0, "Price must be greater than zero");
+
+        // 将NFT信息添加到上架列表中
+        listings[_nftContract][_tokenId] = Listing(
+            _tokenId,
+            msg.sender,
+            _nftContract,
+            _price,
+            true
+        );
+
+        // 如果该合约地址第一次上架NFT，则添加到nftContracts数组中
+        if (nftTokenIds[_nftContract].length == 0) {
+            nftContracts.push(_nftContract);
+        }
+
+        // 将tokenId添加到该合约地址对应的tokenId数组中
+        nftTokenIds[_nftContract].push(_tokenId);
+
+        // 触发上架NFT事件
+        emit NFTListed(_tokenId, msg.sender, _nftContract, _price);
+    }
+
+    // 下架NFT
+    function unListNFT(address _nftContract, uint256 _tokenId) external {
+        // 获取上架信息
+        Listing storage listing = listings[_nftContract][_tokenId];
+        // 确保上架状态为激活
+        require(listing.active, "Listing not active");
+        // 确保下架人是拥有者
+        require(listing.seller == msg.sender, "Not token owner");
+
+        // 修改上架状态为非激活
+        listing.active = false;
+
+        emit NFTUnListed(_tokenId, msg.sender);
+    }
+
+    // 购买NFT
+    function buyNFT(
+        address _nftContract,
+        uint256 _tokenId
+    ) external nonReentrant {
+        Listing storage listing = listings[_nftContract][_tokenId];
+        require(listing.active, "Listing not active");
+
+        IERC721 nft = IERC721(_nftContract);
+        // 确保买家拥有足够的ERC20代币用于购买
+        require(
+            tokenContract.balanceOf(msg.sender) >= listing.price,
+            "Insufficient balance"
+        );
+        // 从买家转移ERC20代币给卖家
+        tokenContract.transferFrom(msg.sender, listing.seller, listing.price);
+        // 从卖家转移NFT给买家
+        nft.transferFrom(listing.seller, msg.sender, _tokenId);
+
+        // 修改上架状态为非激活
+        listing.active = false;
+
+        emit NFTSold(
+            _tokenId,
+            msg.sender,
+            listing.seller,
+            _nftContract,
+            listing.price
+        );
+    }
+
+    // 获取所有上架的NFT信息
+    function getAllListings() external view returns (Listing[] memory) {
+        uint256 totalListings = 0;
+
+        // 计算所有上架的NFT总数
+        for (uint i = 0; i < nftContracts.length; i++) {
+            address nftContract = nftContracts[i];
+            totalListings += nftTokenIds[nftContract].length;
+        }
+
+        // 创建一个数组来存储所有的上架信息
+        Listing[] memory allListings = new Listing[](totalListings);
+        uint256 currentIndex = 0;
+
+        // 填充数组
+        for (uint i = 0; i < nftContracts.length; i++) {
+            address nftContract = nftContracts[i];
+            uint256[] storage tokenIds = nftTokenIds[nftContract];
+            for (uint j = 0; j < tokenIds.length; j++) {
+                uint256 tokenId = tokenIds[j];
+                Listing storage listing = listings[nftContract][tokenId];
+                if (listing.active) {
+                    allListings[currentIndex] = listing;
+                    currentIndex++;
+                }
+            }
+        }
+
+        return allListings;
+    }
+}

members/Georgiafab/task3/README.md

@@ -0,0 +1,8 @@
+## task3 介绍
+
+1. 部署在 Sepolia 测试网上
+   ![bind-wallet](./readme/deploy.png "deploy")
+2. 提交全部合约文件（ERC20、ERC721、NFTMarket）
+3. 提交上架 NFT、购买 NFT 的交易哈希  
+   提交上架 NFT： 0xc940613d9297bcef090bb2252ef9e734dffb769d570b1eafc55931ca46d7f7cd  
+   购买 NFT： 0xf937159ae007f8de3cd163752d66b33a8ad8897926f8e619c9b436c689d864e0