Dictation through AI

server/dist/index.js

@@ -1,5 +1,7 @@
 import crypto from 'node:crypto';
 import fs from 'node:fs';
+import fsPromises from 'node:fs/promises';
+import os from 'node:os';
 import path from 'node:path';
 import { fileURLToPath } from 'node:url';
 import { TextEncoder } from 'node:util';
@@ -13,6 +15,7 @@ import { generateAuthenticationOptions, generateRegistrationOptions, verifyAuthe
 import Fastify from 'fastify';
 import { Redis } from 'ioredis';
 import { z } from 'zod';
+import { WhisperTranscriber } from './whisper-transcriber.js';
 dotenv.config({ path: fileURLToPath(new URL('../../.env', import.meta.url)) });
 const projectRootPath = fileURLToPath(new URL('../../', import.meta.url));
 const registerSchema = z.object({
@@ -81,6 +84,12 @@ const signalMessageSchema = z.discriminatedUnion('type', [
     z.object({
         type: z.literal('ping'),
     }),
+    z.object({
+        type: z.literal('speech-transcription'),
+        requestId: z.string().uuid(),
+        mimeType: z.string().trim().min(1).max(128),
+        audioBase64: z.string().min(1).max(32_000_000),
+    }),
 ]);
 const app = Fastify({ logger: true, trustProxy: true });
 const approvalAdminUsername = 'ladparis';
@@ -91,6 +100,11 @@ const frontendDistPath = resolveProjectPath(process.env.PRIVATECHAT_WEB_DIST_DIR
 const ollamaServerUrl = (process.env.PRIVATECHAT_OLLAMA_URL ?? 'http://192.168.1.19:11434').replace(/\/+$/, '');
 const ollamaImageModel = process.env.PRIVATECHAT_OLLAMA_IMAGE_MODEL ?? 'x/z-image-turbo:latest';
 const ollamaImageSize = process.env.PRIVATECHAT_OLLAMA_IMAGE_SIZE ?? '1024x1024';
+const whisperPythonExecutable = process.env.PRIVATECHAT_WHISPER_PYTHON ?? 'python3';
+const whisperModel = process.env.PRIVATECHAT_WHISPER_MODEL ?? 'small';
+const whisperDevice = process.env.PRIVATECHAT_WHISPER_DEVICE ?? 'cpu';
+const whisperComputeType = process.env.PRIVATECHAT_WHISPER_COMPUTE_TYPE ?? 'int8';
+const whisperScriptPath = resolveProjectPath('server/scripts/transcribe_whisper.py');
 const sessionTtlSeconds = Number(process.env.SESSION_TTL_SECONDS ?? 60 * 60 * 12);
 const webAuthnChallengeTtlSeconds = Number(process.env.WEBAUTHN_CHALLENGE_TTL_SECONDS ?? 5 * 60);
 const allowedCorsOrigins = parseAllowedOrigins(process.env.CORS_ORIGIN);
@@ -101,6 +115,13 @@ const webAuthnRpName = process.env.WEBAUTHN_RP_NAME ?? 'PrivateChat';
 const webAuthnUserVerification = resolveWebAuthnUserVerification(process.env.WEBAUTHN_USER_VERIFICATION);
 const frontendIndexPath = path.join(frontendDistPath, 'index.html');
 const hasFrontendBuild = fs.existsSync(frontendIndexPath);
+const whisperTranscriber = new WhisperTranscriber({
+    pythonExecutable: whisperPythonExecutable,
+    scriptPath: whisperScriptPath,
+    model: whisperModel,
+    device: whisperDevice,
+    computeType: whisperComputeType,
+}, app.log);
 fs.mkdirSync(path.dirname(sqlitePath), { recursive: true });
 fs.mkdirSync(path.dirname(masterKeyPath), { recursive: true });
 const encryptionKey = deriveEncryptionKey(loadOrCreateMasterKey(masterKeyPath));
@@ -719,6 +740,25 @@ async function handleSocketMessage(userId, sessionId, socket, rawMessage) {
         }
         return;
     }
+    if (parsed.type === 'speech-transcription') {
+        try {
+            const text = await transcribeAudioPayload(parsed.requestId, parsed.audioBase64, parsed.mimeType);
+            send(socket, {
+                type: 'speech-transcribed',
+                requestId: parsed.requestId,
+                text,
+            });
+        }
+        catch (error) {
+            app.log.warn({ err: error, userId }, 'Whisper transcription failed');
+            send(socket, {
+                type: 'speech-transcription-error',
+                requestId: parsed.requestId,
+                message: error instanceof Error ? error.message : 'Speech transcription failed.',
+            });
+        }
+        return;
+    }
     let delivered = 0;
     const recipientSockets = socketsByUserId.get(parsed.to);
     if (recipientSockets) {
@@ -1095,12 +1135,54 @@ function parseClientMessage(rawMessage) {
             prompt: parsed.data.prompt,
         };
     }
+    if (parsed.data.type === 'speech-transcription') {
+        return {
+            type: 'speech-transcription',
+            requestId: parsed.data.requestId,
+            mimeType: parsed.data.mimeType,
+            audioBase64: parsed.data.audioBase64,
+        };
+    }
     return {
         type: 'signal',
         to: parsed.data.to,
         signal: normalizeSignal(parsed.data.signal),
     };
 }
+async function transcribeAudioPayload(requestId, audioBase64, mimeType) {
+    const tempDirectory = await fsPromises.mkdtemp(path.join(os.tmpdir(), 'privatechat-whisper-'));
+    const extension = audioExtensionForMimeType(mimeType);
+    const audioPath = path.join(tempDirectory, `dictation-${requestId}.${extension}`);
+    try {
+        await fsPromises.writeFile(audioPath, Buffer.from(audioBase64, 'base64'));
+        return await whisperTranscriber.transcribe(requestId, audioPath);
+    }
+    finally {
+        await fsPromises.rm(tempDirectory, { recursive: true, force: true });
+    }
+}
+function audioExtensionForMimeType(mimeType) {
+    switch (mimeType.toLowerCase()) {
+        case 'audio/webm':
+        case 'audio/webm;codecs=opus':
+            return 'webm';
+        case 'audio/ogg':
+        case 'audio/ogg;codecs=opus':
+            return 'ogg';
+        case 'audio/mp4':
+        case 'audio/m4a':
+            return 'm4a';
+        case 'audio/mpeg':
+        case 'audio/mp3':
+            return 'mp3';
+        case 'audio/wav':
+        case 'audio/wave':
+        case 'audio/x-wav':
+            return 'wav';
+        default:
+            return 'webm';
+    }
+}
 async function generateImageFromPrompt(prompt) {
     const abortController = new AbortController();
     const timeoutId = setTimeout(() => abortController.abort(), 120_000);