修改api路径

app/api/fetcher/media.ts

@@ -0,0 +1,57 @@
+import { promises as fs } from 'fs';
+import os from 'os';
+import path from 'path';
+import { execFile } from 'child_process';
+import { promisify } from 'util';
+
+const execFileAsync = promisify(execFile);
+
+export function pickBestPlayAddr(variants: PlayVariant[] | undefined | null) {
+    if (!variants?.length) return null;
+
+    const best = variants.reduce((best, cur) => {
+        const b1 = best?.bit_rate ?? -1;
+        const b2 = cur?.bit_rate ?? -1;
+        return b2 > b1 ? cur : best;
+    });
+
+    return best?.play_addr ?? null;
+}
+
+/**
+ * 使用 ffmpeg 从视频二进制中提取第一帧，返回 JPEG buffer
+ */
+export async function extractFirstFrame(videoBuffer: Buffer): Promise<{ buffer: Buffer; contentType: string; ext: string } | null> {
+    const ffmpegCmd = process.env.FFMPEG_PATH || 'ffmpeg';
+    const tmpDir = os.tmpdir();
+    const base = `dy_${Date.now()}_${Math.random().toString(36).slice(2, 8)}`;
+    const inPath = path.join(tmpDir, `${base}.mp4`);
+    const outPath = path.join(tmpDir, `${base}.jpg`);
+
+    try {
+        await fs.writeFile(inPath, videoBuffer);
+        const args = [
+            '-hide_banner',
+            '-loglevel', 'error',
+            '-ss', '0',
+            '-i', inPath,
+            '-frames:v', '1',
+            '-q:v', '2',
+            '-f', 'image2',
+            '-y',
+            outPath,
+        ];
+        await execFileAsync(ffmpegCmd, args, { windowsHide: true });
+        const img = await fs.readFile(outPath);
+        return { buffer: img, contentType: 'image/jpeg', ext: 'jpg' };
+    } catch (e: any) {
+        if (e && (e.code === 'ENOENT' || /not found|is not recognized/i.test(String(e.message)))) {
+            console.warn('系统未检测到 ffmpeg，可安装并配置 PATH 或设置 FFMPEG_PATH 后启用封面提取。');
+            return null;
+        }
+        throw e;
+    } finally {
+        try { await fs.unlink(inPath); } catch { }
+        try { await fs.unlink(outPath); } catch { }
+    }
+}