refactor: split downloader into modules

2026-07-22 17:46:35 +08:00
parent 1dfaed4dba
commit 536685e327
15 changed files with 935 additions and 881 deletions
@@ -0,0 +1,139 @@
+const fs = require('fs');
+const path = require('path');
+const { API, DEFAULT_RETRIES, DOWNLOAD_DIR } = require('./config');
+const { addHistory } = require('./history');
+const { fetchLyric, mergeLrc, parseCredits } = require('./lyrics');
+const { fetchNeteaseAlbumDetail, fetchNeteaseSongDetail } = require('./metadata');
+const { downloadFile, fetchJSON } = require('./network');
+const { embedCover } = require('./tagging');
+const { sanitize, sleep } = require('./utils');
+
+async function downloadSong(songId, level, {
+  downloadLyric = true,
+  embedCoverArt = true,
+  maxRetries = DEFAULT_RETRIES,
+  outputDir = DOWNLOAD_DIR,
+  outputBaseName = null,
+} = {}) {
+  let lastError = null;
+  for (let attempt = 1; attempt <= maxRetries; attempt++) {
+    try {
+      return await downloadSongOnce(songId, level, { downloadLyric, embedCoverArt, outputDir, outputBaseName });
+    } catch (e) {
+      lastError = e;
+      if (attempt < maxRetries) {
+        const waitSec = attempt * 3;
+        console.log(`  ⚠️  第 ${attempt} 次失败: ${e.message}，${waitSec}秒后重试...`);
+        await sleep(waitSec * 1000);
+      }
+    }
+  }
+  console.error(`❌ 歌曲 ${songId} 下载失败 (已重试 ${maxRetries} 次): ${lastError?.message}`);
+  return false;
+}
+
+async function downloadSongOnce(songId, level, {
+  downloadLyric = true,
+  embedCoverArt = true,
+  outputDir = DOWNLOAD_DIR,
+  outputBaseName = null,
+} = {}) {
+  console.log(`\n🎵 解析歌曲 ID: ${songId} ...`);
+  const result = await fetchJSON(`${API.music}?id=${songId}&level=${level}`);
+  if (result.code !== 200 || !result.data?.url) throw new Error(result.msg || 'API 返回错误');
+
+  const { name, artist, album, url: audioUrl, br, size, level: actualLevel, picUrl } = result.data;
+  const ext = audioUrl.match(/\.(mp3|flac|m4a|wav|aac)(\?|$)/i)?.[1] || 'mp3';
+  const baseName = sanitize(outputBaseName || `${artist} - ${name}`);
+  const fileName = `${baseName}.${ext}`;
+  fs.mkdirSync(outputDir, { recursive: true });
+  const dest = path.join(outputDir, fileName);
+
+  console.log(`  🎶 ${name} - ${artist}`);
+  console.log(`  💿 ${album} | ${actualLevel} (${br}kbps) | ${(size / 1048576).toFixed(2)} MB`);
+
+  if (fs.existsSync(dest)) {
+    const existStat = fs.statSync(dest);
+    const sizeDiff = Math.abs(existStat.size - size) / size;
+    if (sizeDiff < 0.01) {
+      console.log(`  ⏭️  已存在，跳过: ${fileName}`);
+      const lrcPath = path.join(outputDir, baseName + '.lrc');
+      if (downloadLyric && !fs.existsSync(lrcPath)) {
+        console.log('  🔧 检测到缺少歌词，自动补全...');
+        const lyricData = await fetchLyric(songId);
+        if (lyricData?.lrc) {
+          fs.writeFileSync(lrcPath, lyricData.lrc, 'utf-8');
+          console.log('  📄 歌词已补全');
+          if (lyricData.tlyric?.trim()) {
+            fs.writeFileSync(path.join(outputDir, baseName + '.合并翻译.lrc'), mergeLrc(lyricData.lrc, lyricData.tlyric), 'utf-8');
+          }
+        }
+      }
+    } else {
+      console.log(`  ⚠️  已存在同名文件但大小不同 (现有 ${(existStat.size / 1048576).toFixed(2)} MB, 预期 ${(size / 1048576).toFixed(2)} MB)`);
+      console.log('  ⬇️  覆盖下载...');
+      await downloadFile(audioUrl, dest);
+      console.log(`  ✅ 下载完成: ${fileName}`);
+    }
+  } else {
+    console.log('  ⬇️  下载中...');
+    await downloadFile(audioUrl, dest);
+    console.log(`  ✅ 下载完成: ${fileName}`);
+  }
+
+  let lyricData = null;
+  if (downloadLyric) {
+    lyricData = await fetchLyric(songId);
+    if (lyricData?.lrc) {
+      fs.writeFileSync(path.join(outputDir, baseName + '.lrc'), lyricData.lrc, 'utf-8');
+      console.log(`  📄 歌词已保存: ${baseName}.lrc`);
+      if (lyricData.tlyric?.trim()) {
+        const mergedPath = path.join(outputDir, baseName + '.合并翻译.lrc');
+        fs.writeFileSync(mergedPath, mergeLrc(lyricData.lrc, lyricData.tlyric), 'utf-8');
+        console.log(`  📄 翻译歌词已保存: ${path.basename(mergedPath)}`);
+      }
+    } else {
+      console.log('  ⚠️  未获取到歌词');
+    }
+  }
+
+  if (embedCoverArt && picUrl) {
+    const lrcText = lyricData?.lrc || null;
+    const tagMeta = { name, artist, album, lyrics: lrcText, ...parseCredits(lrcText) };
+    try {
+      const detail = await fetchNeteaseSongDetail(songId);
+      if (detail) {
+        if (detail.trackNo) tagMeta.trackNo = detail.trackNo;
+        if (detail.disc) tagMeta.disc = detail.disc;
+        const albumArtist = detail.artists?.map(item => item.name).join(' / ');
+        if (albumArtist) tagMeta.albumArtist = albumArtist;
+        if (detail.album?.id) {
+          const albumDetail = await fetchNeteaseAlbumDetail(detail.album.id);
+          if (albumDetail?.publishTime) {
+            const date = new Date(albumDetail.publishTime);
+            tagMeta.year = date.getFullYear();
+            tagMeta.date = date.toISOString().slice(0, 10);
+          }
+          if (albumDetail?.tags?.length) tagMeta.genre = albumDetail.tags.join(', ');
+          if (albumDetail?.company) tagMeta.publisher = albumDetail.company;
+          if (tagMeta.trackNo && albumDetail?.size) tagMeta.trackNo = `${tagMeta.trackNo}/${albumDetail.size}`;
+        }
+      }
+    } catch {}
+    await embedCover(dest, picUrl, tagMeta);
+  }
+
+  addHistory({
+    id: songId,
+    name,
+    artist,
+    album,
+    level: actualLevel,
+    bitrate: br,
+    size,
+    file: path.relative(DOWNLOAD_DIR, dest),
+  });
+  return true;
+}
+
+module.exports = { downloadSong };