feat: add support for .proto files

4 files changed, 33 insertions, 1 deletions

diff --git a/packages/cli/src/zed-integration/fileSystemService.ts b/packages/cli/src/zed-integration/fileSystemService.ts
index deb9857f..8e9bd9a4 100644
--- a/packages/cli/src/zed-integration/fileSystemService.ts
+++ b/packages/cli/src/zed-integration/fileSystemService.ts
@@ -33,6 +33,10 @@ export class AcpFileSystemService implements FileSystemService {
     return response.content;
   }
 
+  async readProtoFile(filePath: string): Promise<string> {
+    return this.fallback.readProtoFile(filePath);
+  }
+
   async writeTextFile(filePath: string, content: string): Promise<void> {
     if (!this.capabilities.writeTextFile) {
       return this.fallback.writeTextFile(filePath, content);
diff --git a/packages/core/package.json b/packages/core/package.json
index a694924c..a5ca0fb8 100644
--- a/packages/core/package.json
+++ b/packages/core/package.json
@@ -54,6 +54,7 @@
     "strip-ansi": "^7.1.0",
     "undici": "^7.10.0",
     "ws": "^8.18.0",
+    "protobufjs": "^7.3.2",
     "@xterm/headless": "5.5.0"
   },
   "optionalDependencies": {
diff --git a/packages/core/src/services/fileSystemService.ts b/packages/core/src/services/fileSystemService.ts
index e2f30cf4..3e4cd30f 100644
--- a/packages/core/src/services/fileSystemService.ts
+++ b/packages/core/src/services/fileSystemService.ts
@@ -5,6 +5,7 @@
  */
 
 import fs from 'fs/promises';
+import protobuf from 'protobufjs';
 
 /**
  * Interface for file system operations that may be delegated to different implementations
@@ -19,6 +20,14 @@ export interface FileSystemService {
   readTextFile(filePath: string): Promise<string>;
 
   /**
+   * Read and parse a proto file
+   *
+   * @param filePath - The path to the file to read
+   * @returns The file content as a JSON string
+   */
+  readProtoFile(filePath: string): Promise<string>;
+
+  /**
    * Write text content to a file
    *
    * @param filePath - The path to the file to write
@@ -35,6 +44,11 @@ export class StandardFileSystemService implements FileSystemService {
     return fs.readFile(filePath, 'utf-8');
   }
 
+  async readProtoFile(filePath: string): Promise<string> {
+    const root = await protobuf.load(filePath);
+    return JSON.stringify(root.toJSON(), null, 2);
+  }
+
   async writeTextFile(filePath: string, content: string): Promise<void> {
     await fs.writeFile(filePath, content, 'utf-8');
   }
diff --git a/packages/core/src/utils/fileUtils.ts b/packages/core/src/utils/fileUtils.ts
index f0b491ed..009a4d72 100644
--- a/packages/core/src/utils/fileUtils.ts
+++ b/packages/core/src/utils/fileUtils.ts
@@ -121,7 +121,9 @@ export async function isBinaryFile(filePath: string): Promise<boolean> {
  */
 export async function detectFileType(
   filePath: string,
-): Promise<'text' | 'image' | 'pdf' | 'audio' | 'video' | 'binary' | 'svg'> {
+): Promise<
+  'text' | 'image' | 'pdf' | 'audio' | 'video' | 'binary' | 'svg' | 'proto'
+> {
   const ext = path.extname(filePath).toLowerCase();
 
   // The mimetype for various TypeScript extensions (ts, mts, cts, tsx) can be
@@ -135,6 +137,10 @@ export async function detectFileType(
     return 'svg';
   }
 
+  if (ext === '.proto') {
+    return 'proto';
+  }
+
   const lookedUpMimeType = mime.lookup(filePath); // Returns false if not found, or the mime type string
   if (lookedUpMimeType) {
     if (lookedUpMimeType.startsWith('image/')) {
@@ -280,6 +286,13 @@ export async function processSingleFileContent(
           returnDisplay: `Read SVG as text: ${relativePathForDisplay}`,
         };
       }
+      case 'proto': {
+        const content = await fileSystemService.readProtoFile(filePath);
+        return {
+          llmContent: content,
+          returnDisplay: `Read proto file: ${relativePathForDisplay}`,
+        };
+      }
       case 'text': {
         const content = await fileSystemService.readTextFile(filePath);
         const lines = content.split('\n');