feat(client): createChannel, deleteChannel, deleteSupergroup methods

intentionally no bound method for Chat because it would be way too easy to accidentally delete some chat.

packages/client/src/client.ts

@@ -15,6 +15,8 @@ import { signUp } from './methods/auth/sign-up'
 import { start } from './methods/auth/start'
 import { addChatMembers } from './methods/chats/add-chat-members'
 import { archiveChats } from './methods/chats/archive-chats'
+import { createChannel } from './methods/chats/create-channel'
+import { deleteChannel } from './methods/chats/delete-channel'
 import { getChatPreview } from './methods/chats/get-chat-preview'
 import { getChat } from './methods/chats/get-chat'
 import { getFullChat } from './methods/chats/get-full-chat'
@@ -333,7 +335,8 @@ export class TelegramClient extends BaseTelegramClient {
      *
      * @param chatId  ID of the chat or its username
      * @param users ID(s) of the users, their username(s) or phone(s).
-     * @param forwardCount(default: `100`)
+     * @param forwardCount
+     *  (default: `100`)
      *   Number of old messages to be forwarded (0-100).
      *   Only applicable to legacy groups, ignored for supergroups and channels
      */
@@ -352,6 +355,34 @@ export class TelegramClient extends BaseTelegramClient {
     archiveChats(chats: MaybeArray<InputPeerLike>): Promise<void> {
         return archiveChats.apply(this, arguments)
     }
+    /**
+     * Create a new broadcast channel
+     *
+     * @param title  Channel title
+     * @param description  (default: `''`) Channel description
+     * @returns  Newly created channel
+     */
+    createChannel(title: string, description?: string): Promise<Chat> {
+        return createChannel.apply(this, arguments)
+    }
+
+    /**
+     * Delete a channel or a supergroup
+     *
+     * @param chatId  Chat ID or username
+     */
+    deleteChannel(chatId: InputPeerLike): Promise<void> {
+        return deleteChannel.apply(this, arguments)
+    }
+
+    /**
+     * Delete a channel or a supergroup
+     *
+     * @param chatId  Chat ID or username
+     */
+    deleteSupergroup(chatId: InputPeerLike): Promise<void> {
+        return deleteChannel.apply(this, arguments)
+    }
     /**
      * Get preview information about a private chat.
      *

packages/client/src/methods/chats/create-channel.ts

@@ -0,0 +1,33 @@
+import { TelegramClient } from '../../client'
+import { Chat, MtCuteTypeAssertionError } from '../../types'
+
+/**
+ * Create a new broadcast channel
+ *
+ * @param title  Channel title
+ * @param description  Channel description
+ * @returns  Newly created channel
+ * @internal
+ */
+export async function createChannel(
+    this: TelegramClient,
+    title: string,
+    description = ''
+): Promise<Chat> {
+    const res = await this.call({
+        _: 'channels.createChannel',
+        title,
+        about: description,
+        broadcast: true,
+    })
+
+    if (!(res._ === 'updates' || res._ === 'updatesCombined')) {
+        throw new MtCuteTypeAssertionError(
+            'createChannel (@ channels.createChannel)',
+            'updates | updatesCombined',
+            res._
+        )
+    }
+
+    return new Chat(this, res.chats[0])
+}

packages/client/src/methods/chats/delete-channel.ts

@@ -0,0 +1,20 @@
+import { InputPeerLike, MtCuteInvalidPeerTypeError } from '../../types'
+import { TelegramClient } from '../../client'
+import { normalizeToInputChannel } from '../../utils/peer-utils'
+
+// @alias=deleteSupergroup
+/**
+ * Delete a channel or a supergroup
+ *
+ * @param chatId  Chat ID or username
+ * @internal
+ */
+export async function deleteChannel(this: TelegramClient, chatId: InputPeerLike): Promise<void> {
+    const peer = normalizeToInputChannel(await this.resolvePeer(chatId))
+    if (!peer) throw new MtCuteInvalidPeerTypeError(chatId, 'channel')
+
+    await this.call({
+        _: 'channels.deleteChannel',
+        channel: peer
+    })
+}