1 files changed, 100 insertions, 0 deletions
diff --git a/packages/core/src/ide/ide-client.ts b/packages/core/src/ide/ide-client.ts
new file mode 100644
index 00000000..eeed60b2
--- /dev/null
+++ b/packages/core/src/ide/ide-client.ts
@@ -0,0 +1,100 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import { ideContext, OpenFilesNotificationSchema } from '../ide/ideContext.js';
+import { Client } from '@modelcontextprotocol/sdk/client/index.js';
+import { StreamableHTTPClientTransport } from '@modelcontextprotocol/sdk/client/streamableHttp.js';
+
+const logger = {
+  // eslint-disable-next-line @typescript-eslint/no-explicit-any
+  debug: (...args: any[]) =>
+    console.debug('[DEBUG] [ImportProcessor]', ...args),
+};
+
+export type IDEConnectionState = {
+  status: IDEConnectionStatus;
+  details?: string;
+};
+
+export enum IDEConnectionStatus {
+  Connected = 'connected',
+  Disconnected = 'disconnected',
+  Connecting = 'connecting',
+}
+
+/**
+ * Manages the connection to and interaction with the IDE server.
+ */
+export class IdeClient {
+  client: Client | undefined = undefined;
+  connectionStatus: IDEConnectionStatus = IDEConnectionStatus.Disconnected;
+
+  constructor() {
+    this.connectToMcpServer().catch((err) => {
+      logger.debug('Failed to initialize IdeClient:', err);
+    });
+  }
+  getConnectionStatus(): {
+    status: IDEConnectionStatus;
+    details?: string;
+  } {
+    let details: string | undefined;
+    if (this.connectionStatus === IDEConnectionStatus.Disconnected) {
+      if (!process.env['GEMINI_CLI_IDE_SERVER_PORT']) {
+        details = 'GEMINI_CLI_IDE_SERVER_PORT environment variable is not set.';
+      }
+    }
+    return {
+      status: this.connectionStatus,
+      details,
+    };
+  }
+
+  async connectToMcpServer(): Promise<void> {
+    this.connectionStatus = IDEConnectionStatus.Connecting;
+    const idePort = process.env['GEMINI_CLI_IDE_SERVER_PORT'];
+    if (!idePort) {
+      logger.debug(
+        'Unable to connect to IDE mode MCP server. GEMINI_CLI_IDE_SERVER_PORT environment variable is not set.',
+      );
+      this.connectionStatus = IDEConnectionStatus.Disconnected;
+      return;
+    }
+
+    try {
+      this.client = new Client({
+        name: 'streamable-http-client',
+        // TODO(#3487): use the CLI version here.
+        version: '1.0.0',
+      });
+      const transport = new StreamableHTTPClientTransport(
+        new URL(`http://localhost:${idePort}/mcp`),
+      );
+      await this.client.connect(transport);
+      this.client.setNotificationHandler(
+        OpenFilesNotificationSchema,
+        (notification) => {
+          ideContext.setOpenFilesContext(notification.params);
+        },
+      );
+      this.client.onerror = (error) => {
+        logger.debug('IDE MCP client error:', error);
+        this.connectionStatus = IDEConnectionStatus.Disconnected;
+        ideContext.clearOpenFilesContext();
+      };
+      this.client.onclose = () => {
+        logger.debug('IDE MCP client connection closed.');
+        this.connectionStatus = IDEConnectionStatus.Disconnected;
+        ideContext.clearOpenFilesContext();
+      };
+
+      this.connectionStatus = IDEConnectionStatus.Connected;
+    } catch (error) {
+      this.connectionStatus = IDEConnectionStatus.Disconnected;
+      logger.debug('Failed to connect to MCP server:', error);
+    }
+  }
+}