fixed a bug

sentence_api/ai_tutor.py

@@ -2,6 +2,7 @@
 
 from dataclasses import dataclass
 import logging
+from urllib.parse import urlsplit
 
 import requests
 
@@ -24,6 +25,19 @@ class AITutor:
     def available(self) -> bool:
         return bool(self.endpoint and self.model)
 
+    @property
+    def request_url(self) -> str:
+        """Resolve either a full chat URL or an OpenAI-compatible base URL."""
+        parsed = urlsplit(self.endpoint)
+        path = parsed.path.rstrip("/")
+        if parsed.query or path.endswith("/chat/completions"):
+            return self.endpoint
+        if path.endswith("/v1") or path.endswith("/v1/openai"):
+            return self.endpoint + "/chat/completions"
+        if not path:
+            return self.endpoint + "/v1/chat/completions"
+        return self.endpoint
+
     def explain(
         self,
         sentence_text: str,
@@ -51,7 +65,7 @@ class AITutor:
             headers["Authorization"] = f"Bearer {self.api_key}"
         try:
             response = requests.post(
-                self.endpoint,
+                self.request_url,
                 headers=headers,
                 json={
                     "model": self.model,
@@ -67,7 +81,7 @@ class AITutor:
         except requests.RequestException as exc:
             logger.exception(
                 "AI explanation request failed: endpoint=%s model=%s",
-                self.endpoint,
+                self.request_url,
                 self.model,
             )
             raise AITutorError("AI service request failed.") from exc
@@ -76,7 +90,7 @@ class AITutor:
             logger.warning(
                 "AI explanation returned HTTP %s: endpoint=%s model=%s body=%s",
                 response.status_code,
-                self.endpoint,
+                self.request_url,
                 self.model,
                 response.text[:1000],
             )
@@ -87,14 +101,14 @@ class AITutor:
         except (KeyError, IndexError, TypeError, ValueError) as exc:
             logger.warning(
                 "AI explanation returned an unexpected body: endpoint=%s body=%s",
-                self.endpoint,
+                self.request_url,
                 response.text[:1000],
             )
             raise AITutorError("AI service returned an unexpected response.") from exc
         if not isinstance(explanation, str) or not explanation.strip():
             logger.warning(
                 "AI explanation returned empty content: endpoint=%s body=%s",
-                self.endpoint,
+                self.request_url,
                 response.text[:1000],
             )
             raise AITutorError("AI service returned an empty explanation.")