fix: 降低BangDream歌曲详情渲染峰值

src/modules/qqbot/plugins/bangdream/src/domain/song/song.model.ts

@@ -78,6 +78,7 @@ export class Song {
 
   //meta数据
   hasMeta = false;
+  private readonly songJacketImageCache = new Map<string, Promise<Image>>();
 
   meta: {
     [difficultyId: number]: {
@@ -206,6 +207,18 @@ export class Song {
    */
   async getSongJacketImage(
     displayedServerList: Server[] = [Server.jp, Server.cn],
+  ): Promise<Image> {
+    const cacheKey = displayedServerList.join(',');
+    let jacketImage = this.songJacketImageCache.get(cacheKey);
+    if (!jacketImage) {
+      jacketImage = this.loadSongJacketImage(displayedServerList);
+      this.songJacketImageCache.set(cacheKey, jacketImage);
+    }
+    return await jacketImage;
+  }
+
+  private async loadSongJacketImage(
+    displayedServerList: Server[],
   ): Promise<Image> {
     const jacketImageBuffer = await songResourceRepository.getJacketImageBuffer(
       this,
@@ -357,6 +370,16 @@ export interface SongInRank {
   meta: number;
   rank: number;
 }
+
+export interface SongMetaRankSummary {
+  entries: Array<{
+    difficulty: number;
+    meta: number;
+    rank: number;
+  }>;
+  maxMeta: number;
+}
+
 /**
  * 在BangDream 领域模型层中获取MetaRanking。
  *
@@ -404,3 +427,87 @@ export function getMetaRanking(
   }
   return songRankList;
 }
+
+/**
+ * 在BangDream 领域模型层中获取指定歌曲的Meta排名摘要。
+ *
+ * @param targetSong - 目标歌曲。
+ * @param withFever - withFever参数。
+ * @param mainServer - 主数据服务器参数。
+ * @returns 目标歌曲的排名条目与全局最大Meta。
+ */
+export function getSongMetaRankSummary(
+  targetSong: Song,
+  withFever: boolean,
+  mainServer: Server,
+): SongMetaRankSummary {
+  const songIdList = bangdreamCatalogRepository.getNumericIds('meta');
+  const rowMetas: number[] = [];
+  const targetEntries: Array<{
+    difficulty: number;
+    meta: number;
+    order: number;
+  }> = [];
+  let maxMeta = 0;
+
+  for (let i = 0; i < songIdList.length; i++) {
+    const songId = songIdList[i];
+    const song = songId === targetSong.songId ? targetSong : new Song(songId);
+    if (!isSongMetaRankCandidate(song, mainServer)) {
+      continue;
+    }
+    for (const j in song.difficulty) {
+      const difficulty = parseInt(j);
+      const meta = song.calcMeta(withFever, difficulty);
+      const order = rowMetas.length;
+      rowMetas.push(meta);
+      if (meta > maxMeta) {
+        maxMeta = meta;
+      }
+      if (song.songId === targetSong.songId) {
+        targetEntries.push({
+          difficulty,
+          meta,
+          order,
+        });
+      }
+    }
+  }
+
+  targetEntries.sort((a, b) => {
+    const metaDiff = b.meta - a.meta;
+    return metaDiff === 0 ? a.order - b.order : metaDiff;
+  });
+
+  return {
+    entries: targetEntries.map((entry) => ({
+      difficulty: entry.difficulty,
+      meta: entry.meta,
+      rank: countStableMetaRank(rowMetas, entry.meta, entry.order),
+    })),
+    maxMeta,
+  };
+}
+
+function isSongMetaRankCandidate(song: Song, mainServer: Server): boolean {
+  return (
+    song.publishedAt[mainServer] != null &&
+    Object.keys(song.notes).length > 0 &&
+    song.hasMeta
+  );
+}
+
+function countStableMetaRank(
+  rowMetas: number[],
+  targetMeta: number,
+  targetOrder: number,
+) {
+  let rank = 0;
+  for (let i = 0; i < rowMetas.length; i++) {
+    const meta = rowMetas[i];
+    if (meta > targetMeta || (meta === targetMeta && i < targetOrder)) {
+      rank++;
+    }
+  }
+  return rank;
+}

src/modules/qqbot/plugins/bangdream/src/theme/detail-block.renderer.ts

@@ -12,7 +12,8 @@ import {
 import {
   Song,
   getMetaRanking,
-  SongInRank,
+  getSongMetaRankSummary,
+  type SongMetaRankSummary,
 } from '@/modules/qqbot/plugins/bangdream/src/domain/song/song.model';
 import { drawDottedLine } from '@/modules/qqbot/plugins/bangdream/src/theme/canvas-dotted-line';
 import {
@@ -240,19 +241,9 @@ export async function drawSongMetaListDataBlock(
   topLeftText?: string,
   displayedServerList: Server[] = globalDefaultServer,
 ) {
-  const metaRanking = {};
+  const metaRanking: Partial<Record<Server, SongMetaRankSummary>> = {};
   for (const server of displayedServerList) {
-    metaRanking[server] = {};
-    metaRanking[server].data = getMetaRanking(withFever, server);
-    metaRanking[server].maxMeta = metaRanking[server].data[0].meta;
-  }
-  const songMetaRanking = {};
-  for (const server of displayedServerList) {
-    songMetaRanking[server] = {};
-    const tempMetaRanking = metaRanking[server].data;
-    songMetaRanking[server].data = tempMetaRanking.filter(
-      (value: SongInRank) => value.songId == song.songId,
-    );
+    metaRanking[server] = getSongMetaRankSummary(song, withFever, server);
   }
 
   const list: Array<Image | Canvas> = [];
@@ -260,14 +251,17 @@ export async function drawSongMetaListDataBlock(
     const difficultyId = parseInt(difficulty);
     let text = '';
     for (const server of displayedServerList) {
-      const tempSongMetaRanking = songMetaRanking[server].data;
-      for (let j = 0; j < tempSongMetaRanking.length; j++) {
-        if (tempSongMetaRanking[j].difficulty == difficultyId) {
+      const summary = metaRanking[server];
+      if (!summary) {
+        continue;
+      }
+      for (let j = 0; j < summary.entries.length; j++) {
+        if (summary.entries[j].difficulty == difficultyId) {
           const percent = getRelativeMetaPercent(
-            tempSongMetaRanking[j].meta,
-            metaRanking[server].maxMeta,
+            summary.entries[j].meta,
+            summary.maxMeta,
           );
-          text += `${serverNameFullList[server]}: ${percent}% #${tempSongMetaRanking[j].rank + 1} `;
+          text += `${serverNameFullList[server]}: ${percent}% #${summary.entries[j].rank + 1} `;
         }
       }
     }

test/qqbot/plugins/bangdream/song/song-meta-summary.spec.ts

@@ -0,0 +1,150 @@
+describe('BangDream song meta rank summary', () => {
+  it('matches full meta ranking entries for a single song', async () => {
+    jest.resetModules();
+    jest.doMock(
+      '@/modules/qqbot/plugins/bangdream/src/application/catalog/bangdream-catalog-cache',
+      () => ({
+        __esModule: true,
+        default: createCatalogFixture(),
+      }),
+    );
+
+    const { Server } = await import(
+      '@/modules/qqbot/plugins/bangdream/src/domain/catalog/server.model'
+    );
+    const songModule = await import(
+      '@/modules/qqbot/plugins/bangdream/src/domain/song/song.model'
+    );
+    const { Song, getMetaRanking } = songModule;
+    const getSongMetaRankSummary = (
+      songModule as typeof songModule & {
+        getSongMetaRankSummary?: (
+          song: InstanceType<typeof Song>,
+          withFever: boolean,
+          server: typeof Server.cn,
+        ) => {
+          entries: Array<{ difficulty: number; meta: number; rank: number }>;
+          maxMeta: number;
+        };
+      }
+    ).getSongMetaRankSummary;
+
+    const song = new Song(243);
+    const fullRanking = getMetaRanking(true, Server.cn);
+    expect(typeof getSongMetaRankSummary).toBe('function');
+    const summary = getSongMetaRankSummary(song, true, Server.cn);
+
+    expect(summary.maxMeta).toBe(fullRanking[0].meta);
+    expect(summary.entries).toEqual(
+      fullRanking
+        .filter((entry) => entry.songId === 243)
+        .map(({ difficulty, meta, rank }) => ({ difficulty, meta, rank })),
+    );
+  });
+
+  it('caches jacket image decoding within a song instance', async () => {
+    const getJacketImageBuffer = jest
+      .fn<Promise<Buffer>, [unknown]>()
+      .mockResolvedValue(Buffer.from('fake-png'));
+    const loadImage = jest.fn(async () => ({
+      height: 1,
+      width: 1,
+    }));
+
+    jest.resetModules();
+    jest.doMock(
+      '@/modules/qqbot/plugins/bangdream/src/application/catalog/bangdream-catalog-cache',
+      () => ({
+        __esModule: true,
+        default: createCatalogFixture(),
+      }),
+    );
+    jest.doMock(
+      '@/modules/qqbot/plugins/bangdream/src/domain/song/song-resource.repository',
+      () => ({
+        songResourceRepository: {
+          getChart: jest.fn(),
+          getDetail: jest.fn(),
+          getJacketImageBuffer,
+          getJacketImagePath: jest.fn(),
+          getSongRip: jest.fn(),
+          resolveJacketImageUrl: jest.fn(),
+        },
+      }),
+    );
+    jest.doMock('skia-canvas', () => ({
+      loadImage,
+    }));
+
+    const { Song } = await import(
+      '@/modules/qqbot/plugins/bangdream/src/domain/song/song.model'
+    );
+
+    const song = new Song(243);
+    const first = await song.getSongJacketImage();
+    const second = await song.getSongJacketImage();
+
+    expect(first).toBe(second);
+    expect(getJacketImageBuffer).toHaveBeenCalledTimes(1);
+    expect(loadImage).toHaveBeenCalledTimes(1);
+  });
+});
+
+function createCatalogFixture() {
+  return {
+    meta: {
+      100: createMeta({ 1: 90, 2: 60 }),
+      243: createMeta({ 1: 50, 2: 70 }),
+      300: createMeta({ 1: 100, 2: 100 }),
+      400: createMeta({ 1: 70, 2: 70 }),
+    },
+    songs: {
+      100: createSong({ id: 100, publishedCn: true }),
+      243: createSong({ id: 243, publishedCn: true }),
+      300: createSong({ id: 300, publishedCn: false }),
+      400: createSong({ id: 400, publishedCn: true }),
+    },
+  };
+}
+
+function createSong({
+  id,
+  publishedCn,
+}: {
+  id: number;
+  publishedCn: boolean;
+}) {
+  return {
+    bandId: 1,
+    bpm: {
+      1: [{ bpm: 120, end: 1, start: 0 }],
+      2: [{ bpm: 140, end: 1, start: 0 }],
+    },
+    closedAt: [],
+    difficulty: {
+      1: { playLevel: 20 },
+      2: { playLevel: 25 },
+    },
+    jacketImage: [`song-${id}`],
+    length: 120,
+    musicTitle: [`Song ${id}`, null, null, `歌曲 ${id}`, null],
+    nickname: null,
+    notes: {
+      1: 500,
+      2: 700,
+    },
+    publishedAt: [null, null, null, publishedCn ? 1 : null, null],
+    tag: 'normal',
+  };
+}
+
+function createMeta(values: Record<number, number>) {
+  return Object.fromEntries(
+    Object.entries(values).map(([difficulty, value]) => [
+      difficulty,
+      {
+        7: [0, value, 0, value],
+      },
+    ]),
+  );
+}