1 files changed, 39 insertions, 27 deletions

diff --git a/g4f/Provider/FreeGpt.py b/g4f/Provider/FreeGpt.py
index f79f0a66..7fa3b5ab 100644
--- a/g4f/Provider/FreeGpt.py
+++ b/g4f/Provider/FreeGpt.py
@@ -1,55 +1,67 @@
 from __future__ import annotations
 
-import time, hashlib, random
-
-from ..typing import AsyncResult, Messages
+import time
+import hashlib
+import random
+from typing import AsyncGenerator, Optional, Dict, Any
+from ..typing import Messages
 from ..requests import StreamSession, raise_for_status
 from .base_provider import AsyncGeneratorProvider
 from ..errors import RateLimitError
 
-domains = [
+# Constants
+DOMAINS = [
     "https://s.aifree.site",
     "https://v.aifree.site/"
 ]
+RATE_LIMIT_ERROR_MESSAGE = "当前地区当日额度已消耗完"
+
 
 class FreeGpt(AsyncGeneratorProvider):
-    url = "https://freegptsnav.aifree.site"
-    working = True
-    supports_message_history = True
-    supports_system_message = True
-    supports_gpt_35_turbo = True
+    url: str = "https://freegptsnav.aifree.site"
+    working: bool = True
+    supports_message_history: bool = True
+    supports_system_message: bool = True
+    supports_gpt_35_turbo: bool = True
 
     @classmethod
     async def create_async_generator(
         cls,
         model: str,
         messages: Messages,
-        proxy: str = None,
+        proxy: Optional[str] = None,
         timeout: int = 120,
-        **kwargs
-    ) -> AsyncResult:
+        **kwargs: Any
+    ) -> AsyncGenerator[str, None]:
+        prompt = messages[-1]["content"]
+        timestamp = int(time.time())
+        data = cls._build_request_data(messages, prompt, timestamp)
+
+        domain = random.choice(DOMAINS)
+
         async with StreamSession(
             impersonate="chrome",
             timeout=timeout,
-            proxies={"all": proxy}
+            proxies={"all": proxy} if proxy else None
         ) as session:
-            prompt = messages[-1]["content"]
-            timestamp = int(time.time())
-            data = {
-                "messages": messages,
-                "time": timestamp,
-                "pass": None,
-                "sign": generate_signature(timestamp, prompt)
-            }
-            domain = random.choice(domains)
             async with session.post(f"{domain}/api/generate", json=data) as response:
                 await raise_for_status(response)
                 async for chunk in response.iter_content():
-                    chunk = chunk.decode(errors="ignore")
-                    if chunk == "当前地区当日额度已消耗完":
+                    chunk_decoded = chunk.decode(errors="ignore")
+                    if chunk_decoded == RATE_LIMIT_ERROR_MESSAGE:
                         raise RateLimitError("Rate limit reached")
-                    yield chunk
-    
-def generate_signature(timestamp: int, message: str, secret: str = ""):
+                    yield chunk_decoded
+
+    @staticmethod
+    def _build_request_data(messages: Messages, prompt: str, timestamp: int, secret: str = "") -> Dict[str, Any]:
+        return {
+            "messages": messages,
+            "time": timestamp,
+            "pass": None,
+            "sign": generate_signature(timestamp, prompt, secret)
+        }
+
+
+def generate_signature(timestamp: int, message: str, secret: str = "") -> str:
     data = f"{timestamp}:{message}:{secret}"
     return hashlib.sha256(data.encode()).hexdigest()