feat(editor): add language server connection via WebSocket

src/lib/language-server.ts

@@ -0,0 +1,70 @@
+import normalizeUrl from "normalize-url";
+import type { MessageTransports } from "vscode-languageclient";
+import { EditorLanguageMetadata } from "@/types/editor-language";
+import type { MonacoLanguageClient } from "monaco-languageclient";
+import { toSocket, WebSocketMessageReader, WebSocketMessageWriter } from "vscode-ws-jsonrpc";
+
+// Create the WebSocket URL based on the protocol and port
+function createUrl(protocol: string, hostname: string, port: number | null, path: string | null): string {
+  const formattedPort = port !== null ? `:${port}` : "";
+  const formattedPath = path ? (path.startsWith("/") ? path : `/${path}`) : "";
+  return normalizeUrl(`${protocol}://${hostname}${formattedPort}${formattedPath}`);
+}
+
+// Create the language client with the given transports
+async function createLanguageClient(transports: MessageTransports, lang: EditorLanguageMetadata): Promise<MonacoLanguageClient> {
+  const { MonacoLanguageClient } = await import("monaco-languageclient");
+  const { CloseAction, ErrorAction } = await import("vscode-languageclient");
+
+  return new MonacoLanguageClient({
+    name: `${lang.label} Language Client`,
+    clientOptions: {
+      // use a language id as a document selector
+      documentSelector: [lang.id],
+      // disable the default error handler
+      errorHandler: {
+        error: () => ({ action: ErrorAction.Continue }),
+        closed: () => ({ action: CloseAction.DoNotRestart }),
+      },
+    },
+    // create a language client connection from the JSON RPC connection on demand
+    connectionProvider: {
+      get: () => {
+        return Promise.resolve(transports);
+      }
+    }
+  });
+}
+
+// Connect to the WebSocket and create the language client
+export function connectToLanguageServer(protocol: string, hostname: string, port: number | null, path: string | null, lang: EditorLanguageMetadata): Promise<MonacoLanguageClient> {
+  const url = createUrl(protocol, hostname, port, path);
+  const webSocket = new WebSocket(url);
+
+  return new Promise((resolve, reject) => {
+    // Handle the WebSocket opening event
+    webSocket.onopen = async () => {
+      const socket = toSocket(webSocket);
+      const reader = new WebSocketMessageReader(socket);
+      const writer = new WebSocketMessageWriter(socket);
+
+      try {
+        const languageClient = await createLanguageClient({ reader, writer }, lang);
+        // Start the language client
+        languageClient.start();
+
+        // Stop the language client when the reader closes
+        reader.onClose(() => languageClient.stop());
+
+        resolve(languageClient);
+      } catch (error) {
+        reject(error);
+      }
+    };
+
+    // Handle WebSocket errors
+    webSocket.onerror = (error) => {
+      reject(error);
+    };
+  });
+}