gemini backup if openai unavailable

.dockerignore

@@ -0,0 +1,7 @@
+__pycache__/
+*.pyc
+.env
+.git
+.gitignore
+.vscode/
+notes.txt

.gitignore

@@ -0,0 +1,2 @@
+.env
+notes.txt

app/main.py

@@ -27,13 +27,15 @@ except ImportError:
 
 # We keep the GEMINI_* env vars for compatibility.
 API_KEY = os.getenv("GEMINI_API_KEY", "")
-MODEL   = os.getenv("GEMINI_MODEL", "gemini-2.0-pro")
-SMALL_MODEL = os.getenv("GEMINI_SMALL_MODEL")
-OPENAI_API_KEY = os.getenv("OPENAI_API_KEY") or API_KEY
+MODEL   = os.getenv("GEMINI_MODEL", "gemini-2.5-pro")
+GEMINI_SMALL_MODEL = os.getenv("GEMINI_SMALL_MODEL")
+OPENAI_SMALL_MODEL = os.getenv("OPENAI_SMALL_MODEL") or "gpt-4o-mini"
+OPENAI_API_KEY = os.getenv("OPENAI_API_KEY")
+USE_OPENAI = os.getenv("USE_OPENAI", "").lower() == "true"
 PORT    = int(os.getenv("PORT", "7860"))
 
 gemini_client = genai.Client(api_key=API_KEY) if API_KEY else None
-gpt_client = OpenAI(api_key=OPENAI_API_KEY) if (OPENAI_API_KEY and OpenAI) else None
+gpt_client = OpenAI(api_key=OPENAI_API_KEY) if (OPENAI_API_KEY and OpenAI and USE_OPENAI) else None
 
 # -------- FastAPI app --------
 app = FastAPI(title="Manim Render API (error + visual refine)")
@@ -225,10 +227,20 @@ def gemini_call(*, system: str, contents):
 
 
 def gemini_small_call(*, system: str, contents: str) -> str:
-    """Lightweight wrapper for the storyboard assistant (smaller model)."""
-    target_model = SMALL_MODEL or "gpt-4o-mini"
+    """Lightweight wrapper for the storyboard assistant using a smaller model with Gemini fallback."""
     storyboard_limiter.acquire()
-    return _invoke_gpt_model(target_model, system, contents)
+    if gpt_client:
+        target_model = OPENAI_SMALL_MODEL
+        return _invoke_gpt_model(target_model, system, contents)
+    if not gemini_client:
+        raise RuntimeError("Gemini client is not configured")
+    fallback_model = GEMINI_SMALL_MODEL or MODEL
+    resp = gemini_client.models.generate_content(
+        model=fallback_model,
+        config=types.GenerateContentConfig(system_instruction=system),
+        contents=contents,
+    )
+    return getattr(resp, "text", str(resp))
 
 # ---------------- prompts ----------------
 SYSTEM_PROMPT = """You are a Manim CE (0.19.x) code generator/refiner.
@@ -1128,7 +1140,7 @@ def _auto_fix_render(
 # ---------------- API ----------------
 @app.post("/storyboard/chat")
 def storyboard_chat(inp: StoryboardChatIn):
-    if not gpt_client:
+    if not (gpt_client or gemini_client):
         raise HTTPException(500, "Storyboard model is not configured")
     if not inp.message.strip() and not inp.plan:
         raise HTTPException(400, "Message or plan updates are required.")
@@ -1167,7 +1179,7 @@ def storyboard_chat(inp: StoryboardChatIn):
 
 @app.post("/storyboard/confirm")
 def storyboard_confirm(inp: StoryboardConfirmIn):
-    if not gpt_client:
+    if not (gpt_client or gemini_client):
         raise HTTPException(500, "Storyboard model is not configured")
 
     session = _get_or_create_session(inp.session_id, inp.settings or {})