build video support

backend/src/services/image.ts

@@ -1,7 +1,11 @@
 import sharp from 'sharp';
 import fs from 'fs';
+import { execFile } from 'child_process';
+import { promisify } from 'util';
 import { absolutePath, ensureDir } from './storage.js';
 
+const execFileAsync = promisify(execFile);
+
 export interface ImageMeta {
   width: number;
   height: number;
@@ -29,6 +33,30 @@ export async function extractMeta(filePath: string): Promise<ImageMeta> {
   };
 }
 
+export async function extractVideoMeta(filePath: string, mimeType: string): Promise<ImageMeta> {
+  const abs = absolutePath(filePath);
+  const stat = fs.statSync(abs);
+  try {
+    const { stdout } = await execFileAsync('ffprobe', [
+      '-v', 'quiet',
+      '-print_format', 'json',
+      '-show_streams',
+      abs,
+    ]);
+    const data = JSON.parse(stdout);
+    const video = (data.streams as any[])?.find((s) => s.codec_type === 'video');
+    return {
+      width: video?.width ?? 1280,
+      height: video?.height ?? 720,
+      mimeType,
+      size: stat.size,
+    };
+  } catch {
+    // ffprobe unavailable or failed — use safe defaults
+    return { width: 1280, height: 720, mimeType, size: stat.size };
+  }
+}
+
 export async function saveBuffer(buffer: Buffer, destRelPath: string): Promise<void> {
   ensureDir(destRelPath);
   const abs = absolutePath(destRelPath);