documents preview

server/dist/index.js

@@ -2,13 +2,14 @@ import crypto from 'node:crypto';
 import fs from 'node:fs';
 import path from 'node:path';
 import { fileURLToPath } from 'node:url';
-import { TextEncoder } from 'node:util';
+import { promisify, TextEncoder } from 'node:util';
 import { DatabaseSync } from 'node:sqlite';
 import cors from '@fastify/cors';
 import jwt from '@fastify/jwt';
 import fastifyStatic from '@fastify/static';
 import websocket from '@fastify/websocket';
 import dotenv from 'dotenv';
+import libreOffice from 'libreoffice-convert';
 import { generateAuthenticationOptions, generateRegistrationOptions, verifyAuthenticationResponse, verifyRegistrationResponse, } from '@simplewebauthn/server';
 import Fastify from 'fastify';
 import { Redis } from 'ioredis';
@@ -47,6 +48,11 @@ const adminDeleteUserParamsSchema = z.object({
 const webBundleFileParamsSchema = z.object({
     '*': z.string().min(1),
 });
+const officePreviewSchema = z.object({
+    fileName: z.string().trim().min(1).max(256),
+    mimeType: z.string().trim().min(1).max(256),
+    fileBase64: z.string().min(1).max(96_000_000),
+});
 const wsQuerySchema = z.object({
     token: z.string().min(1),
 });
@@ -111,6 +117,7 @@ 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 convertOfficeDocument = promisify(libreOffice.convertWithOptions);
 const speechTranscriber = new SpeechTranscriber({
     serviceUrl: speechTranscriptionServiceUrl,
     language: speechTranscriptionLanguage,
@@ -462,6 +469,35 @@ app.get('/api/auth/session', async (request, reply) => {
         messageEncryptionKey: authContext.user.messageEncryptionKey,
     };
 });
+app.post('/api/files/office-preview', { bodyLimit: 64 * 1024 * 1024 }, async (request, reply) => {
+    const authContext = await authenticateRequest(request, reply);
+    if (!authContext) {
+        return;
+    }
+    const parsed = officePreviewSchema.safeParse(request.body);
+    if (!parsed.success) {
+        return reply.code(400).send({
+            message: 'Invalid office preview payload.',
+            issues: parsed.error.flatten(),
+        });
+    }
+    if (!isSupportedOfficeDocument(parsed.data.fileName, parsed.data.mimeType)) {
+        return reply.code(400).send({ message: 'Only DOCX, XLSX, and PPTX files can be previewed.' });
+    }
+    try {
+        const pdfBuffer = await convertOfficeDocumentToPdf(parsed.data.fileName, parsed.data.fileBase64);
+        return {
+            mimeType: 'application/pdf',
+            pdfBase64: pdfBuffer.toString('base64'),
+        };
+    }
+    catch (error) {
+        app.log.warn({ err: error, userId: authContext.user.id }, 'Office preview generation failed');
+        return reply.code(422).send({
+            message: describeOfficePreviewFailure(error),
+        });
+    }
+});
 app.get('/api/admin/pending-users', async (request, reply) => {
     const authContext = await authenticateRequest(request, reply);
     if (!authContext) {
@@ -835,6 +871,36 @@ async function authenticateTokenFromSession(userId, sessionId, decoded) {
         },
     };
 }
+async function convertOfficeDocumentToPdf(fileName, fileBase64) {
+    const inputBuffer = Buffer.from(fileBase64, 'base64');
+    if (inputBuffer.byteLength === 0) {
+        throw new Error('The uploaded office document is empty.');
+    }
+    const normalizedFileName = normalizeOfficeDocumentFileName(fileName);
+    return convertOfficeDocument(inputBuffer, '.pdf', undefined, { fileName: normalizedFileName });
+}
+function isSupportedOfficeDocument(fileName, mimeType) {
+    const normalizedFileName = fileName.trim().toLowerCase();
+    const normalizedMimeType = mimeType.trim().toLowerCase();
+    if (normalizedMimeType === 'application/vnd.openxmlformats-officedocument.wordprocessingml.document'
+        || normalizedMimeType === 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet'
+        || normalizedMimeType === 'application/vnd.openxmlformats-officedocument.presentationml.presentation') {
+        return true;
+    }
+    return /\.(docx|xlsx|xslx|pptx)$/i.test(normalizedFileName);
+}
+function normalizeOfficeDocumentFileName(fileName) {
+    return fileName.trim().replace(/\.xslx$/i, '.xlsx');
+}
+function describeOfficePreviewFailure(error) {
+    if (error && typeof error === 'object' && 'code' in error && error.code === 'ENOENT') {
+        return 'Office preview generation failed because LibreOffice is not installed on the server.';
+    }
+    if (error instanceof Error && error.message.trim()) {
+        return `Office preview generation failed: ${error.message}`;
+    }
+    return 'Office preview generation failed.';
+}
 function createUser(input) {
     const createdAt = new Date().toISOString();
     const user = {