fix(speech): convert base64 TTS data URI before playback per platform

后端 TTS 以 data: URI 返回 base64 mp3(生产实证为合法 LAME mp3),但 App-Plus 的 InnerAudioContext 不支持 data: URI,iOS Safari/微信 webview 也常静默失败,统一报"语音播放失败"。播放前按平台转换:H5 转 Blob URL, App 端经 plus.io 落 _doc/ 临时文件后播放 file:// 路径,播完清理;Blob 不可用时退回原始 data: URI。竞态守卫与缓存语义保持不变,158 单测全绿。
2026-07-25 20:37:30 +08:00
parent c2358686ce
commit ab3af277c1
3 changed files with 173 additions and 17 deletions
@@ -0,0 +1,112 @@
+/**
+ * 语音播放的音源适配。
+ *
+ * 后端 TTS 以 data: URI(base64 mp3)返回;uni.createInnerAudioContext 在
+ * App-Plus 不支持 data: URI,iOS Safari/微信 webview 对 data: URI 音频也
+ * 经常静默失败。因此播放前统一转换:H5 转 Blob URL,App 端落临时文件。
+ */
+
+export interface DecodedAudioDataUri {
+  mime: string;
+  bytes: Uint8Array;
+}
+
+const DATA_AUDIO_URI_PATTERN = /^data:(audio\/[\w.+-]+);base64,([A-Za-z0-9+/=\r\n]+)$/i;
+
+export const isDataAudioUri = (source: string) => DATA_AUDIO_URI_PATTERN.test(source);
+
+/** 纯解析,不依赖浏览器 API,便于单测。base64 非法或不是音频 data URI 时返回 null。 */
+export const decodeDataAudioUri = (dataUri: string): DecodedAudioDataUri | null => {
+  const match = DATA_AUDIO_URI_PATTERN.exec(dataUri);
+  if (!match) return null;
+  try {
+    const binary = atob(match[2].replace(/[\r\n]/g, ''));
+    const bytes = new Uint8Array(binary.length);
+    for (let i = 0; i < binary.length; i += 1) bytes[i] = binary.charCodeAt(i);
+    if (bytes.length === 0) return null;
+    return { mime: match[1], bytes };
+  } catch {
+    return null;
+  }
+};
+
+/** H5:base64 转 Blob URL,规避 iOS Safari/微信对 data: URI 音频的兼容问题。 */
+export const dataUriToBlobUrl = (dataUri: string): string | null => {
+  const decoded = decodeDataAudioUri(dataUri);
+  if (!decoded || typeof Blob === 'undefined' || typeof URL === 'undefined'
+    || typeof URL.createObjectURL !== 'function') return null;
+  const blobBytes = new Uint8Array(decoded.bytes);
+  return URL.createObjectURL(new Blob([blobBytes], { type: decoded.mime }));
+};
+
+interface PlusIoFileEntry {
+  fullPath: string;
+  createWriter: (ok: (writer: PlusIoWriter) => void, fail?: (err: unknown) => void) => void;
+  remove: (ok?: () => void, fail?: (err: unknown) => void) => void;
+}
+
+interface PlusIoWriter {
+  onwriteend: (() => void) | null;
+  onerror: ((err: unknown) => void) | null;
+  write: (data: Blob) => void;
+}
+
+interface PlusIoDirectoryEntry {
+  getFile: (
+    path: string,
+    flags: { create: boolean },
+    ok: (entry: PlusIoFileEntry) => void,
+    fail?: (err: unknown) => void
+  ) => void;
+}
+
+interface PlusIo {
+  resolveLocalFileSystemURL: (
+    path: string,
+    ok: (entry: PlusIoDirectoryEntry & PlusIoFileEntry) => void,
+    fail?: (err: unknown) => void
+  ) => void;
+  convertLocalFileSystemURL: (path: string) => string;
+}
+
+const resolvePlusIo = (): PlusIo | null => {
+  const plus = (globalThis as typeof globalThis & { plus?: { io?: PlusIo } }).plus;
+  return plus && plus.io ? plus.io : null;
+};
+
+/** 是否处于需要落盘播放的 App-Plus 原生环境(避免与 speech-capture 循环引用,本地判定)。 */
+export const hasNativeAudioFileSupport = () => resolvePlusIo() !== null;
+
+/** App-Plus:base64 落 `_doc/` 临时文件,返回可播放的 file:// 路径;失败返回 null。 */
+export const writeNativeTempAudio = (dataUri: string): Promise<string | null> => {
+  const decoded = decodeDataAudioUri(dataUri);
+  const io = resolvePlusIo();
+  if (!decoded || !io) return Promise.resolve(null);
+  return new Promise((resolve) => {
+    try {
+      io.resolveLocalFileSystemURL('_doc/', (dir) => {
+        dir.getFile(`aihr-tts-${Date.now()}.mp3`, { create: true }, (fileEntry) => {
+          fileEntry.createWriter((writer) => {
+            writer.onwriteend = () => resolve(io.convertLocalFileSystemURL(fileEntry.fullPath));
+            writer.onerror = () => resolve(null);
+            const blobBytes = new Uint8Array(decoded.bytes);
+            writer.write(new Blob([blobBytes], { type: decoded.mime }));
+          }, () => resolve(null));
+        }, () => resolve(null));
+      }, () => resolve(null));
+    } catch {
+      resolve(null);
+    }
+  });
+};
+
+/** 播放结束后清理 App 端临时文件,尽力而为。 */
+export const removeNativeTempAudio = (fileUrl: string) => {
+  const io = resolvePlusIo();
+  if (!io) return;
+  try {
+    io.resolveLocalFileSystemURL(fileUrl, (entry) => entry.remove());
+  } catch {
+    // 清理失败不影响播放主流程
+  }
+};