From df84137391d8dabec4b957684ab9685815c1ce30 Mon Sep 17 00:00:00 2001
From: teidesu <me@tei.su>
Date: Sun, 9 May 2021 18:29:33 +0300
Subject: [PATCH] feat(client): get messages inside message groups

---
 packages/client/src/client.ts                 |  9 ++++++
 .../src/methods/messages/get-message-group.ts | 31 +++++++++++++++++++
 packages/client/src/types/messages/message.ts | 14 +++++++++
 3 files changed, 54 insertions(+)
 create mode 100644 packages/client/src/methods/messages/get-message-group.ts

diff --git a/packages/client/src/client.ts b/packages/client/src/client.ts
index f856ad11..937a226c 100644
--- a/packages/client/src/client.ts
+++ b/packages/client/src/client.ts
@@ -67,6 +67,7 @@ import { editMessage } from './methods/messages/edit-message'
 import { _findMessageInUpdate } from './methods/messages/find-in-update'
 import { forwardMessages } from './methods/messages/forward-messages'
 import { getHistory } from './methods/messages/get-history'
+import { getMessageGroup } from './methods/messages/get-message-group'
 import { getMessages } from './methods/messages/get-messages'
 import { iterHistory } from './methods/messages/iter-history'
 import { _parseEntities } from './methods/messages/parse-entities'
@@ -1496,6 +1497,13 @@ export interface TelegramClient extends BaseTelegramClient {
             reverse?: boolean
         }
     ): Promise<Message[]>
+    /**
+     * Get all messages inside of a message group
+     *
+     * @param chatId  Chat ID
+     * @param message  ID of one of the messages in the group
+     */
+    getMessageGroup(chatId: InputPeerLike, message: number): Promise<Message[]>
     /**
      * Get a single message in chat by its ID
      *
@@ -2555,6 +2563,7 @@ export class TelegramClient extends BaseTelegramClient {
     protected _findMessageInUpdate = _findMessageInUpdate
     forwardMessages = forwardMessages
     getHistory = getHistory
+    getMessageGroup = getMessageGroup
     getMessages = getMessages
     iterHistory = iterHistory
     protected _parseEntities = _parseEntities
diff --git a/packages/client/src/methods/messages/get-message-group.ts b/packages/client/src/methods/messages/get-message-group.ts
new file mode 100644
index 00000000..a044f4b5
--- /dev/null
+++ b/packages/client/src/methods/messages/get-message-group.ts
@@ -0,0 +1,31 @@
+import { TelegramClient } from '../../client'
+import { InputPeerLike, MtCuteArgumentError, Message } from '../../types'
+
+/**
+ * Get all messages inside of a message group
+ *
+ * @param chatId  Chat ID
+ * @param message  ID of one of the messages in the group
+ * @internal
+ */
+export async function getMessageGroup(
+    this: TelegramClient,
+    chatId: InputPeerLike,
+    message: number
+): Promise<Message[]> {
+    // awesome hack stolen from pyrogram
+    // groups have no more than 10 items
+
+    const ids: number[] = []
+    for (let i = Math.max(message - 9, 0); i <= message + 9; i++) {
+        ids.push(i)
+    }
+
+    const messages = await this.getMessages(chatId, ids)
+    const groupedId = messages.find((it) => it.id === message)!.groupedId
+
+    if (!groupedId)
+        throw new MtCuteArgumentError('This message is not grouped')
+
+    return messages.filter((it) => it.groupedId?.eq(groupedId))
+}
diff --git a/packages/client/src/types/messages/message.ts b/packages/client/src/types/messages/message.ts
index 635411f7..56dc7ef7 100644
--- a/packages/client/src/types/messages/message.ts
+++ b/packages/client/src/types/messages/message.ts
@@ -924,6 +924,20 @@ export class Message {
 
         return this.client.sendText(toChatId, this.raw.message, params)
     }
+
+    /**
+     * Get all messages inside a group that this
+     * message belongs to (see {@link groupedId}),
+     * including this message.
+     *
+     * In case this message is not inside of a group,
+     * will just return itself.
+     */
+    async getGroup(): Promise<Message[]> {
+        if (!this.groupedId) return [this]
+
+        return this.client.getMessageGroup(this.chat.inputPeer, this.raw.id)
+    }
 }