refactor: streamline telegram voice fallback

src/telegram/bot/delivery.test.ts

@@ -17,6 +17,9 @@ vi.mock("grammy", () => ({
       public fileName?: string,
     ) {}
   },
+  GrammyError: class GrammyError extends Error {
+    description = "";
+  },
 }));
 
 describe("deliverReplies", () => {

src/telegram/bot/delivery.ts

@@ -1,4 +1,4 @@
-import { type Bot, InputFile } from "grammy";
+import { type Bot, GrammyError, InputFile } from "grammy";
 import {
   markdownToTelegramChunks,
   markdownToTelegramHtml,
@@ -22,6 +22,7 @@ import { buildTelegramThreadParams, resolveTelegramReplyId } from "./helpers.js"
 import type { TelegramContext } from "./types.js";
 
 const PARSE_ERR_RE = /can't parse entities|parse entities|find end of the entity/i;
+const VOICE_FORBIDDEN_RE = /VOICE_MESSAGES_FORBIDDEN/;
 
 export async function deliverReplies(params: {
   replies: ReplyPayload[];
@@ -163,31 +164,26 @@ export async function deliverReplies(params: {
             // Fall back to text if voice messages are forbidden in this chat.
             // This happens when the recipient has Telegram Premium privacy settings
             // that block voice messages (Settings > Privacy > Voice Messages).
-            const errMsg = formatErrorMessage(voiceErr);
-            if (errMsg.includes("VOICE_MESSAGES_FORBIDDEN")) {
-              if (!reply.text?.trim()) {
+            if (isVoiceMessagesForbidden(voiceErr)) {
+              const fallbackText = reply.text;
+              if (!fallbackText || !fallbackText.trim()) {
                 throw voiceErr;
               }
               logVerbose(
                 "telegram sendVoice forbidden (recipient has voice messages blocked in privacy settings); falling back to text",
               );
-              // Send the text content instead of the voice message.
-              if (reply.text) {
-                const chunks = chunkText(reply.text);
-                for (const chunk of chunks) {
-                  await sendTelegramText(bot, chatId, chunk.html, runtime, {
-                    replyToMessageId:
-                      replyToId && (replyToMode === "all" || !hasReplied) ? replyToId : undefined,
-                    messageThreadId,
-                    textMode: "html",
-                    plainText: chunk.text,
-                    linkPreview,
-                  });
-                  if (replyToId && !hasReplied) {
-                    hasReplied = true;
-                  }
-                }
-              }
+              hasReplied = await sendTelegramVoiceFallbackText({
+                bot,
+                chatId,
+                runtime,
+                text: fallbackText,
+                chunkText,
+                replyToId,
+                replyToMode,
+                hasReplied,
+                messageThreadId,
+                linkPreview,
+              });
               // Skip this media item; continue with next.
               continue;
             }
@@ -263,6 +259,43 @@ export async function resolveMedia(
   return { path: saved.path, contentType: saved.contentType, placeholder };
 }
 
+function isVoiceMessagesForbidden(err: unknown): boolean {
+  if (err instanceof GrammyError) {
+    return VOICE_FORBIDDEN_RE.test(err.description);
+  }
+  return VOICE_FORBIDDEN_RE.test(formatErrorMessage(err));
+}
+
+async function sendTelegramVoiceFallbackText(opts: {
+  bot: Bot;
+  chatId: string;
+  runtime: RuntimeEnv;
+  text: string;
+  chunkText: (markdown: string) => ReturnType<typeof markdownToTelegramChunks>;
+  replyToId?: number;
+  replyToMode: ReplyToMode;
+  hasReplied: boolean;
+  messageThreadId?: number;
+  linkPreview?: boolean;
+}): Promise<boolean> {
+  const chunks = opts.chunkText(opts.text);
+  let hasReplied = opts.hasReplied;
+  for (const chunk of chunks) {
+    await sendTelegramText(opts.bot, opts.chatId, chunk.html, opts.runtime, {
+      replyToMessageId:
+        opts.replyToId && (opts.replyToMode === "all" || !hasReplied) ? opts.replyToId : undefined,
+      messageThreadId: opts.messageThreadId,
+      textMode: "html",
+      plainText: chunk.text,
+      linkPreview: opts.linkPreview,
+    });
+    if (opts.replyToId && !hasReplied) {
+      hasReplied = true;
+    }
+  }
+  return hasReplied;
+}
+
 function buildTelegramSendParams(opts?: {
   replyToMessageId?: number;
   messageThreadId?: number;