Function decodeReaction

packages/bot-telegram/src/interaction.ts:107–149

(update: unknown)

 * Only `type === "emoji"` entries are considered; custom_emoji are ignored.
 */
export function decodeReaction(update: unknown): IncomingReaction[] {
  const mr = (update as { message_reaction?: TgMessageReaction })
    .message_reaction;
  if (!mr?.chat?.id || mr.message_id === undefined) return [];
  const oldSet = emojiSet(mr.old_reaction);
  const newSet = emojiSet(mr.new_reaction);
  const chatId = mr.chat.id;
  const message = {
    chat: mr.chat as { id: number | string; type: string; is_forum?: boolean },
    message_id: mr.message_id,
    message_thread_id: mr.message_thread_id,
  };
  const ck = deriveConversationKey(message, mr.user?.id);
  const conversationKey = conversationKeyOf(ck);
  const replyTarget: ReplyTarget = {
    chatId,
    messageThreadId: mr.chat.is_forum ? mr.message_thread_id : undefined,
    conversationKey,
  };
  const user = mr.user
    ? {
        id: String(mr.user.id),
        name: mr.user.first_name,
        handle: mr.user.username,
      }
    : undefined;
  const base = {
    user,
    conversationKey,
    replyTarget,
    messageId: String(mr.message_id),
    // Update-capable ref (chatId + numeric messageId) so an onReaction handler
    // can edit the reacted message in place via thread.update.
    messageRef: { id: String(mr.message_id), chatId, messageId: mr.message_id },
    raw: update,
  };
  const out: IncomingReaction[] = [];
  for (const e of newSet)
    if (!oldSet.has(e)) out.push({ ...base, rawEmoji: e, added: true });
  for (const e of oldSet)
    if (!newSet.has(e)) out.push({ ...base, rawEmoji: e, added: false });
  return out;
}

/**
 * Decode a Telegram callback_query update (grammY or raw Bot API) into a