feat: add Telegram API utilities

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

src/utils/telegram.js

@@ -0,0 +1,60 @@
+import { Telegraf } from 'telegraf';
+import logger from './logger.js';
+import { config } from '../env.js';
+
+const bot = new Telegraf(config.botToken);
+const TELEGRAM_API_URL = `https://api.telegram.org/bot${config.botToken}/`;
+
+export const forwardToStorage = async (fileChunk, fileName, forceDocument = false) => {
+  try {
+    const caption = forceDocument ? `📁 ${fileName}` : fileName;
+    const input = forceDocument ? { document: fileChunk, caption } : { photo: [fileChunk], caption };
+
+    const result = await bot.api.sendPhoto(config.storageChatId, input);
+
+    logger.info('File forwarded to storage', { fileName, message: result.message_id });
+
+    return {
+      telegramFileId: result.photo?.slice(-1)[0]?.file_id,
+      telegramFileUniqueId: result.photo?.slice(-1)[0]?.file_unique_id,
+      storageMessageId: result.message_id
+    };
+  } catch (error) {
+    logger.error('Failed to forward file to storage', { fileName, error: error.message });
+    throw error;
+  }
+};
+
+export const getFileInfo = async (telegramFileId, telegramFileUniqueId) => {
+  try {
+    const result = await fetch(`${TELEGRAM_API_URL}getFile`);
+    const data = await result.json();
+
+    if (!data.ok) {
+      throw new Error(data.description || 'Telegram API error');
+    }
+
+    const fileId = data.result.file_id === telegramFileId ? telegramFileId : telegramFileUniqueId;
+    const fileResult = await fetch(`${TELEGRAM_API_URL}getInfo`, {
+      method: 'POST',
+      headers: { 'Content-Type': 'application/json' },
+      body: JSON.stringify({ file_id: fileId })
+    });
+    const fileInfo = await fileResult.json();
+
+    if (!fileInfo.ok) {
+      throw new Error(fileInfo.description || 'Telegram info error');
+    }
+
+    return {
+      file_size: fileInfo.result.file_size,
+      mime_type: fileInfo.result.mime_type,
+      file_path: fileInfo.result.file_path
+    };
+  } catch (error) {
+    logger.error('Failed to get file info', { error: error.message });
+    throw error;
+  }
+};
+
+export const getBot = () => bot;