feat(bot): add proxy limit

backend/src/bot/handlers/proxy/handler.py

@@ -1,4 +1,5 @@
-from dataclasses import dataclass
+import contextlib
+from dataclasses import dataclass, field
 
 from aiogram import Bot, Router, types
 from aiogram.client.default import DefaultBotProperties
@@ -13,6 +14,8 @@ class ProxyConfig:
     bot_token: str
     target_chat_id: int
     proxy_bot: Bot
+    limit: int = 0
+    message_count: int = field(default=0, init=False)
 
 
 proxy_states: dict[int, ProxyConfig] = {}
@@ -28,25 +31,43 @@ async def cleanup_proxy(chat_id: int) -> None:
         await config.proxy_bot.session.close()
 
 
+async def increment_proxy_count(chat_id: int) -> bool:
+    config = proxy_states.get(chat_id)
+    if not config:
+        return False
+
+    config.message_count += 1
+
+    if config.limit > 0 and config.message_count >= config.limit:
+        await config.proxy_bot.send_message(
+            config.target_chat_id, f"🔗 Proxy finished ({config.limit} messages)"
+        )
+        await cleanup_proxy(chat_id)
+        return False
+
+    return True
+
+
 @router.message(Command("proxy"))
-async def on_proxy(message: types.Message) -> None:  # noqa: C901
+async def on_proxy(message: types.Message) -> None:  # noqa: C901, PLR0912
     if not message.from_user or not message.text:
         return
 
     chat_id = message.chat.id
-    args = message.text.split(maxsplit=2)
+    args = message.text.split(maxsplit=3)
 
     if len(args) == 1:
         config = get_proxy_config(chat_id)
         if config:
+            cnt = f" ({config.message_count}/{config.limit})" if config.limit else ""
             await message.answer(
-                f"Proxy active → chat {config.target_chat_id}\n\n"
+                f"Proxy active → chat {config.target_chat_id}{cnt}\n\n"
                 "Use /proxy deactivate to stop."
             )
         else:
             await message.answer(
                 "Usage:\n"
-                "/proxy BOT_TOKEN CHAT_ID - activate proxy\n"
+                "/proxy BOT_TOKEN CHAT_ID [LIMIT] - activate proxy\n"
                 "/proxy deactivate - stop proxy"
             )
         return
@@ -60,7 +81,7 @@ async def on_proxy(message: types.Message) -> None:  # noqa: C901
         return
 
     if len(args) < 3:  # noqa: PLR2004
-        await message.answer("Usage: /proxy BOT_TOKEN CHAT_ID")
+        await message.answer("Usage: /proxy BOT_TOKEN CHAT_ID [LIMIT]")
         return
 
     bot_token = args[1]
@@ -70,6 +91,11 @@ async def on_proxy(message: types.Message) -> None:  # noqa: C901
         await message.answer("Invalid chat ID. Must be a number.")
         return
 
+    limit = 0
+    if len(args) >= 4:  # noqa: PLR2004
+        with contextlib.suppress(ValueError):
+            limit = max(int(args[3]), 0)
+
     if chat_id in proxy_states:
         await cleanup_proxy(chat_id)
 
@@ -87,12 +113,16 @@ async def on_proxy(message: types.Message) -> None:  # noqa: C901
             return
 
         proxy_states[chat_id] = ProxyConfig(
-            bot_token=bot_token, target_chat_id=target_chat_id, proxy_bot=proxy_bot
+            bot_token=bot_token,
+            target_chat_id=target_chat_id,
+            proxy_bot=proxy_bot,
+            limit=limit,
         )
 
+        limit_text = f"\nLimit: {limit} messages" if limit > 0 else ""
         await message.answer(
             f"✓ Proxy activated via @{bot_info.username}\n"
-            f"Target: {target_chat_id}\n\n"
+            f"Target: {target_chat_id}{limit_text}\n\n"
             "All messages will be forwarded."
         )
         await message.delete()