func readDownloadMetadata()

in Sources/Hub/HubApi.swift [244:286]
36 lines of code
6 McCabe index (conditional complexity)

    func readDownloadMetadata(metadataPath: URL) throws -> LocalDownloadFileMetadata? {
        if FileManager.default.fileExists(atPath: metadataPath.path) {
            do {
                let contents = try String(contentsOf: metadataPath, encoding: .utf8)
                let lines = contents.components(separatedBy: .newlines)

                guard lines.count >= 3 else {
                    throw EnvironmentError.invalidMetadataError(String(localized: "Metadata file is missing required fields"))
                }

                let commitHash = lines[0].trimmingCharacters(in: .whitespacesAndNewlines)
                let etag = lines[1].trimmingCharacters(in: .whitespacesAndNewlines)

                guard let timestamp = Double(lines[2].trimmingCharacters(in: .whitespacesAndNewlines)) else {
                    throw EnvironmentError.invalidMetadataError(String(localized: "Invalid timestamp format"))
                }

                let timestampDate = Date(timeIntervalSince1970: timestamp)
                let filename = metadataPath.lastPathComponent.replacingOccurrences(of: ".metadata", with: "")

                return LocalDownloadFileMetadata(commitHash: commitHash, etag: etag, filename: filename, timestamp: timestampDate)
            } catch let error as EnvironmentError {
                do {
                    HubApi.logger.warning("Invalid metadata file \(metadataPath): \(error.localizedDescription). Removing it from disk and continuing.")
                    try FileManager.default.removeItem(at: metadataPath)
                } catch {
                    throw EnvironmentError.invalidMetadataError(String(localized: "Could not remove corrupted metadata file: \(error.localizedDescription)"))
                }
                return nil
            } catch {
                do {
                    HubApi.logger.warning("Error reading metadata file \(metadataPath): \(error.localizedDescription). Removing it from disk and continuing.")
                    try FileManager.default.removeItem(at: metadataPath)
                } catch {
                    throw EnvironmentError.invalidMetadataError(String(localized: "Could not remove corrupted metadata file: \(error.localizedDescription)"))
                }
                return nil
            }
        }

        // metadata file does not exist
        return nil
    }