Add Telegram and Discord IM channels

src/channels/telegram/telegram-api.mjs

@@ -0,0 +1,120 @@
+const DEFAULT_BASE_URL = 'https://api.telegram.org/';
+
+function cleanString(value) {
+  return typeof value === 'string' && value.trim() ? value.trim() : null;
+}
+
+function requestSignal(signal, timeoutMs) {
+  const timeout = AbortSignal.timeout(timeoutMs);
+  return signal ? AbortSignal.any([signal, timeout]) : timeout;
+}
+
+export function validTelegramToken(value) {
+  return typeof value === 'string' && /^\d{5,20}:[A-Za-z0-9_-]{20,}$/.test(value.trim());
+}
+
+export class TelegramApi {
+  #token;
+  #fetch;
+  #baseUrl;
+
+  constructor({ token, fetchImpl = fetch, baseUrl = DEFAULT_BASE_URL }) {
+    if (!validTelegramToken(token)) throw new TypeError('Telegram Bot Token is invalid');
+    if (typeof fetchImpl !== 'function') throw new TypeError('TelegramApi requires fetch');
+    this.#token = token.trim();
+    this.#fetch = fetchImpl;
+    this.#baseUrl = new URL(baseUrl);
+  }
+
+  async getMe(options = {}) {
+    return this.#call('getMe', {}, options);
+  }
+
+  async getWebhookInfo(options = {}) {
+    return this.#call('getWebhookInfo', {}, options);
+  }
+
+  async getUpdates({ offset, timeout = 25, signal } = {}) {
+    const payload = {
+      timeout,
+      limit: 100,
+      allowed_updates: ['message'],
+      ...(Number.isSafeInteger(offset) ? { offset } : {}),
+    };
+    return this.#call('getUpdates', payload, {
+      signal,
+      timeoutMs: Math.max(10_000, (timeout + 10) * 1_000),
+    });
+  }
+
+  async sendMessage({ chatId, text, replyToMessageId, messageThreadId, signal }) {
+    return this.#call('sendMessage', {
+      chat_id: chatId,
+      text,
+      link_preview_options: { is_disabled: true },
+      ...(replyToMessageId ? {
+        reply_parameters: { message_id: replyToMessageId, allow_sending_without_reply: true },
+      } : {}),
+      ...(messageThreadId ? { message_thread_id: messageThreadId } : {}),
+    }, { signal });
+  }
+
+  async editMessageText({ chatId, messageId, text, signal }) {
+    return this.#call('editMessageText', {
+      chat_id: chatId,
+      message_id: messageId,
+      text,
+      link_preview_options: { is_disabled: true },
+    }, { signal });
+  }
+
+  async sendChatAction({ chatId, messageThreadId, signal }) {
+    return this.#call('sendChatAction', {
+      chat_id: chatId,
+      action: 'typing',
+      ...(messageThreadId ? { message_thread_id: messageThreadId } : {}),
+    }, { signal });
+  }
+
+  async #call(method, payload, { signal, timeoutMs = 15_000 } = {}) {
+    const url = new URL(this.#baseUrl);
+    url.pathname = `${url.pathname.replace(/\/$/, '')}/bot${this.#token}/${method}`;
+    let response;
+    try {
+      response = await this.#fetch(url, {
+        method: 'POST',
+        headers: { 'content-type': 'application/json' },
+        body: JSON.stringify(payload),
+        signal: requestSignal(signal, timeoutMs),
+        redirect: 'error',
+      });
+    } catch (error) {
+      if (error?.name === 'AbortError' || error?.name === 'TimeoutError') throw error;
+      throw new Error(`Telegram ${method} transport failed`);
+    }
+    let body;
+    try {
+      body = await response.json();
+    } catch {
+      throw new Error(`Telegram ${method} returned invalid JSON`);
+    }
+    if (!response.ok || body?.ok !== true) {
+      const description = cleanString(body?.description);
+      const error = new Error(description ?? `Telegram ${method} failed`);
+      error.code = Number.isInteger(body?.error_code) ? `telegram-${body.error_code}` : 'telegram-api-error';
+      throw error;
+    }
+    return body.result;
+  }
+}
+
+export async function inspectTelegramToken(token, options = {}) {
+  const api = new TelegramApi({ token, ...options });
+  const bot = await api.getMe();
+  if (!bot?.id || bot?.is_bot !== true) throw new Error('Telegram token does not belong to a bot');
+  return {
+    platformId: String(bot.id),
+    name: cleanString([bot.first_name, bot.last_name].filter(Boolean).join(' ')) ?? 'Telegram机器人',
+    username: cleanString(bot.username),
+  };
+}