feat: add PackageRegistry contract #4

Author: zacksfF

src/core/PackageRegistry.sol

@@ -0,0 +1,120 @@
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.0;
+
+import "../interfaces/IPackageRegistry.sol";
+import "../structs/PackageStructs.sol";
+
+/// @title PackageRegistry
+/// @notice On-chain registry for EthPM v3 packages (EIP-2678)
+/// @dev Stores package references with content-addressable URIs (IPFS)
+contract PackageRegistry is IPackageRegistry {
+    
+    // Package name => version => manifest URI (IPFS/Swarm)
+    mapping(string => mapping(string => string)) private packages;
+    
+    // Package name => owner address
+    mapping(string => address) private packageOwners;
+    
+    // Package name => all versions
+    mapping(string => string[]) private packageVersions;
+    
+    // Events
+    event PackagePublished(string indexed name, string version, string manifestURI, address publisher);
+    event PackageOwnershipTransferred(string indexed name, address previousOwner, address newOwner);
+    
+    /// @notice Publish a package to the registry
+    /// @param name Package name (must be lowercase, numbers, hyphens only)
+    /// @param version Package version (semver format)
+    /// @param manifestURI Content-addressable URI (ipfs:// or bzz://)
+    function publish(string calldata name, string calldata version, string calldata manifestURI) external override {
+        require(bytes(name).length > 0, "Package name cannot be empty");
+        require(bytes(version).length > 0, "Version cannot be empty");
+        require(bytes(manifestURI).length > 0, "Manifest URI cannot be empty");
+        require(_isValidPackageName(name), "Invalid package name format");
+        
+        // Check ownership
+        if (packageOwners[name] == address(0)) {
+            // First time publishing this package
+            packageOwners[name] = msg.sender;
+        } else {
+            // Only owner can publish new versions
+            require(packageOwners[name] == msg.sender, "Only package owner can publish");
+        }
+        
+        // Check if version already exists
+        require(bytes(packages[name][version]).length == 0, "Version already exists");
+        
+        // Store package
+        packages[name][version] = manifestURI;
+        packageVersions[name].push(version);
+        
+        emit PackagePublished(name, version, manifestURI, msg.sender);
+    }
+    
+    /// @notice Get package manifest URI
+    /// @param name Package name
+    /// @param version Package version
+    /// @return manifestURI The content-addressable URI of the package manifest
+    function getPackageURI(string calldata name, string calldata version) external view override returns (string memory) {
+        string memory uri = packages[name][version];
+        require(bytes(uri).length > 0, "Package version does not exist");
+        return uri;
+    }
+    
+    /// @notice Check if package version exists
+    /// @param name Package name
+    /// @param version Package version
+    /// @return exists True if package exists
+    function packageExists(string calldata name, string calldata version) external view override returns (bool) {
+        return bytes(packages[name][version]).length > 0;
+    }
+    
+    /// @notice Get all versions of a package
+    /// @param name Package name
+    /// @return versions Array of all versions
+    function getVersions(string calldata name) external view returns (string[] memory) {
+        return packageVersions[name];
+    }
+    
+    /// @notice Get package owner
+    /// @param name Package name
+    /// @return owner Address of package owner
+    function getOwner(string calldata name) external view returns (address) {
+        return packageOwners[name];
+    }
+    
+    /// @notice Transfer package ownership
+    /// @param name Package name
+    /// @param newOwner New owner address
+    function transferOwnership(string calldata name, address newOwner) external {
+        require(packageOwners[name] == msg.sender, "Only owner can transfer ownership");
+        require(newOwner != address(0), "New owner cannot be zero address");
+        
+        address previousOwner = packageOwners[name];
+        packageOwners[name] = newOwner;
+        
+        emit PackageOwnershipTransferred(name, previousOwner, newOwner);
+    }
+    
+    /// @notice Validate package name format (lowercase, numbers, hyphens)
+    /// @param name Package name to validate
+    /// @return valid True if name is valid
+    function _isValidPackageName(string calldata name) private pure returns (bool) {
+        bytes memory nameBytes = bytes(name);
+        
+        for (uint256 i = 0; i < nameBytes.length; i++) {
+            bytes1 char = nameBytes[i];
+            
+            // Allow: a-z, 0-9, hyphen
+            bool isLowercase = (char >= 0x61 && char <= 0x7A); // a-z
+            bool isNumber = (char >= 0x30 && char <= 0x39);    // 0-9
+            bool isHyphen = (char == 0x2D);                     // -
+            
+            if (!isLowercase && !isNumber && !isHyphen) {
+                return false;
+            }
+        }
+        
+        return true;
+    }
+}