From 60f8e832e0d17825dc3bc6710a12bc88046bc2f1 Mon Sep 17 00:00:00 2001
From: SidQin-cyber <sidqin0410@gmail.com>
Date: Mon, 2 Mar 2026 09:19:52 +0800
Subject: [PATCH] fix(telegram): handle sendVoice caption-too-long by resending
 without caption

When TTS text exceeds Telegram's 1024-char caption limit, sendVoice
throws "message caption is too long" and the entire reply (voice +
text) is lost. Now catch this specific error, resend the voice note
without caption, then deliver the full text as a separate message.

Closes #30980

Made-with: Cursor
---
 src/telegram/bot/delivery.ts | 43 +++++++++++++++++++++++++++++++++---
 1 file changed, 40 insertions(+), 3 deletions(-)

diff --git a/src/telegram/bot/delivery.ts b/src/telegram/bot/delivery.ts
index 748fca00a..abf79c2cc 100644
--- a/src/telegram/bot/delivery.ts
+++ b/src/telegram/bot/delivery.ts
@@ -35,6 +35,7 @@ import type { StickerMetadata, TelegramContext } from "./types.js";
 const PARSE_ERR_RE = /can't parse entities|parse entities|find end of the entity/i;
 const EMPTY_TEXT_ERR_RE = /message text is empty/i;
 const VOICE_FORBIDDEN_RE = /VOICE_MESSAGES_FORBIDDEN/;
+const CAPTION_TOO_LONG_RE = /caption is too long/i;
 const FILE_TOO_BIG_RE = /file is too big/i;
 const TELEGRAM_MEDIA_SSRF_POLICY = {
   // Telegram file downloads should trust api.telegram.org even when DNS/proxy
@@ -230,8 +231,6 @@ export async function deliverReplies(params: {
             markDelivered();
           } catch (voiceErr) {
             // 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).
             if (isVoiceMessagesForbidden(voiceErr)) {
               const fallbackText = reply.text;
               if (!fallbackText || !fallbackText.trim()) {
@@ -256,7 +255,38 @@ export async function deliverReplies(params: {
                 hasReplied = true;
               }
               markDelivered();
-              // Skip this media item; continue with next.
+              continue;
+            }
+            if (isCaptionTooLong(voiceErr)) {
+              logVerbose(
+                "telegram sendVoice caption too long; resending voice without caption + text separately",
+              );
+              const noCaptionParams = { ...mediaParams };
+              delete noCaptionParams.caption;
+              delete noCaptionParams.parse_mode;
+              await withTelegramApiErrorLogging({
+                operation: "sendVoice",
+                runtime,
+                fn: () => bot.api.sendVoice(chatId, file, { ...noCaptionParams }),
+              });
+              markDelivered();
+              const fallbackText = reply.text;
+              if (fallbackText?.trim()) {
+                await sendTelegramVoiceFallbackText({
+                  bot,
+                  chatId,
+                  runtime,
+                  text: fallbackText,
+                  chunkText,
+                  replyToId: undefined,
+                  thread,
+                  linkPreview,
+                  replyMarkup,
+                });
+              }
+              if (replyToMessageIdForPayload && !hasReplied) {
+                hasReplied = true;
+              }
               continue;
             }
             throw voiceErr;
@@ -463,6 +493,13 @@ function isVoiceMessagesForbidden(err: unknown): boolean {
   return VOICE_FORBIDDEN_RE.test(formatErrorMessage(err));
 }
 
+function isCaptionTooLong(err: unknown): boolean {
+  if (err instanceof GrammyError) {
+    return CAPTION_TOO_LONG_RE.test(err.description);
+  }
+  return CAPTION_TOO_LONG_RE.test(formatErrorMessage(err));
+}
+
 /**
  * Returns true if the error is Telegram's "file is too big" error.
  * This happens when trying to download files >20MB via the Bot API.