feat(dispatcher): added getCompleteChat and withCompleteChat, similar to getCompleteSender withCompleteSender

packages/dispatcher/src/context/message.ts

@@ -1,4 +1,4 @@
-import type { OmitInputMessageId, ParametersSkip1, Peer, Sticker } from '@mtcute/core'
+import type { Chat, OmitInputMessageId, ParametersSkip1, Peer, Sticker } from '@mtcute/core'
 import { Message, MtPeerNotFoundError } from '@mtcute/core'
 import type { TelegramClient } from '@mtcute/core/client.js'
 import type {
@@ -67,6 +67,23 @@ export class MessageContext extends Message implements UpdateContext<Message> {
         return res
     }
 
+    /**
+     * Get complete information about {@link chat}
+     *
+     * Learn more: [Incomplete peers](https://mtcute.dev/guide/topics/peers.html#incomplete-peers)
+     */
+    async getCompleteChat(): Promise<Chat> {
+        if (!this.chat.isMin) return this.chat
+
+        const res = await this.client.getChat(this.chat)
+
+        if (!res) throw new MtPeerNotFoundError('Failed to fetch chat')
+
+        Object.defineProperty(this, 'chat', { value: res })
+
+        return res
+    }
+
     /** Get a message that this message is a reply to */
     getReplyTo(): Promise<Message | null> {
         return this.client.getReplyTo(this)

packages/dispatcher/src/filters/message.ts

@@ -296,3 +296,23 @@ export function withCompleteSender<Mod, State extends object>(
         return filter(msg, state)
     }
 }
+
+/**
+ * Middleware-like filter that will fetch the chat of the message
+ * and make it available to further filters, as well as the handler itself.
+ */
+export function withCompleteChat<Mod, State extends object>(
+    filter?: UpdateFilter<MessageContext, Mod, State>,
+): UpdateFilter<MessageContext, Mod, State> {
+    return async (msg, state) => {
+        try {
+            await msg.getCompleteChat()
+        } catch {
+            return false
+        }
+
+        if (!filter) return true
+
+        return filter(msg, state)
+    }
+}