fix(stats): fetch cover art eagerly at session start instead of on series page visit (#148)

src/core/services/stats-server.ts

@@ -17,6 +17,7 @@ import {
 } from '../../anki-field-config.js';
 import { resolveAnimatedImageLeadInSeconds } from '../../anki-integration/animated-image-sync.js';
 import type { AnilistRateLimiter } from './anilist/rate-limiter.js';
+import { registerStatsCoverRoutes } from './stats-cover-routes.js';
 import {
   resolveRetimedSecondarySubtitleTextFromSidecar,
   resolveSecondarySubtitleTextFromSidecar,
@@ -51,16 +52,6 @@ type StatsExcludedWordPayload = {
   reading: string;
 };
 
-type StatsCoverImagePayload = {
-  contentType: string;
-  dataUrl: string;
-} | null;
-
-type StatsCoverBatchBody = {
-  animeIds?: unknown;
-  videoIds?: unknown;
-};
-
 function parseIntQuery(raw: string | undefined, fallback: number, maxLimit?: number): number {
   if (raw === undefined) return fallback;
   const n = Number(raw);
@@ -113,62 +104,6 @@ function parseExcludedWordsBody(body: unknown): StatsExcludedWordPayload[] | nul
   return words;
 }
 
-function parsePositiveIdList(raw: unknown, maxItems = 100): number[] {
-  if (!Array.isArray(raw)) return [];
-
-  const ids = new Set<number>();
-  for (const rawId of raw) {
-    const id = typeof rawId === 'number' ? rawId : typeof rawId === 'string' ? Number(rawId) : NaN;
-    if (Number.isFinite(id) && id > 0) {
-      ids.add(Math.floor(id));
-      if (ids.size >= maxItems) break;
-    }
-  }
-
-  return Array.from(ids).sort((a, b) => a - b);
-}
-
-function coverImagePayload(
-  art: { coverBlob?: Uint8Array | null } | null | undefined,
-): StatsCoverImagePayload {
-  if (!art?.coverBlob) return null;
-  const bytes = new Uint8Array(art.coverBlob);
-  const contentType = detectImageContentType(bytes);
-  return {
-    contentType,
-    dataUrl: `data:${contentType};base64,${Buffer.from(bytes).toString('base64')}`,
-  };
-}
-
-function detectImageContentType(bytes: Uint8Array): string {
-  if (
-    bytes.length >= 8 &&
-    bytes[0] === 0x89 &&
-    bytes[1] === 0x50 &&
-    bytes[2] === 0x4e &&
-    bytes[3] === 0x47
-  ) {
-    return 'image/png';
-  }
-  if (bytes.length >= 3 && bytes[0] === 0xff && bytes[1] === 0xd8 && bytes[2] === 0xff) {
-    return 'image/jpeg';
-  }
-  if (
-    bytes.length >= 12 &&
-    bytes[0] === 0x52 &&
-    bytes[1] === 0x49 &&
-    bytes[2] === 0x46 &&
-    bytes[3] === 0x46 &&
-    bytes[8] === 0x57 &&
-    bytes[9] === 0x45 &&
-    bytes[10] === 0x42 &&
-    bytes[11] === 0x50
-  ) {
-    return 'image/webp';
-  }
-  return 'application/octet-stream';
-}
-
 function resolveStatsNoteFieldName(
   noteInfo: StatsServerNoteInfo,
   ...preferredNames: (string | undefined)[]
@@ -1017,58 +952,7 @@ export function createStatsApp(
     return c.json({ ok: true });
   });
 
-  app.post('/api/stats/covers', async (c) => {
-    const body = (await c.req.json().catch(() => null)) as StatsCoverBatchBody | null;
-    const animeIds = parsePositiveIdList(body?.animeIds);
-    const videoIds = parsePositiveIdList(body?.videoIds);
-    const anime: Record<number, StatsCoverImagePayload> = {};
-    const media: Record<number, StatsCoverImagePayload> = {};
-
-    await Promise.all(
-      animeIds.map(async (animeId) => {
-        anime[animeId] = coverImagePayload(await tracker.getAnimeCoverArt(animeId));
-      }),
-    );
-    await Promise.all(
-      videoIds.map(async (videoId) => {
-        media[videoId] = coverImagePayload(await tracker.getCoverArt(videoId));
-      }),
-    );
-
-    return c.json({ anime, media });
-  });
-
-  app.get('/api/stats/anime/:animeId/cover', async (c) => {
-    const animeId = parseIntQuery(c.req.param('animeId'), 0);
-    if (animeId <= 0) return c.body(null, 404);
-    const art = await tracker.getAnimeCoverArt(animeId);
-    if (!art?.coverBlob) return c.body(null, 404);
-    const bytes = new Uint8Array(art.coverBlob);
-    return new Response(bytes, {
-      headers: {
-        'Content-Type': detectImageContentType(bytes),
-        'Cache-Control': 'public, max-age=86400',
-      },
-    });
-  });
-
-  app.get('/api/stats/media/:videoId/cover', async (c) => {
-    const videoId = parseIntQuery(c.req.param('videoId'), 0);
-    if (videoId <= 0) return c.body(null, 404);
-    let art = await tracker.getCoverArt(videoId);
-    if (!art?.coverBlob) {
-      await tracker.ensureCoverArt(videoId);
-      art = await tracker.getCoverArt(videoId);
-    }
-    if (!art?.coverBlob) return c.body(null, 404);
-    const bytes = new Uint8Array(art.coverBlob);
-    return new Response(bytes, {
-      headers: {
-        'Content-Type': detectImageContentType(bytes),
-        'Cache-Control': 'public, max-age=604800',
-      },
-    });
-  });
+  registerStatsCoverRoutes(app, tracker);
 
   app.get('/api/stats/episode/:videoId/detail', async (c) => {
     const videoId = parseIntQuery(c.req.param('videoId'), 0);