Add demo mode support - enable API without Groq client

main.py

@@ -65,6 +65,10 @@ class QueryResponse(BaseModel):
 def generate_sql_with_groq(question: str) -> tuple:
     """Generate SQL using Groq AI"""
     try:
+        # Return demo SQL if Groq client is not available
+        if not groq_client:
+            demo_sql = "SELECT c.name, SUM(o.total) as order_total FROM customers c JOIN orders o ON c.id = o.customer_id GROUP BY c.name ORDER BY order_total DESC"
+            return demo_sql, None
         # Sample database schema
         schema = """
         Database Schema:
@@ -104,6 +108,9 @@ SQL Query:"""
 def explain_sql_with_groq(sql: str, question: str) -> str:
     """Generate explanation for SQL query"""
     try:
+        # Return demo explanation if Groq client is not available
+        if not groq_client:
+            return "This query retrieves data from the database. Full AI explanation unavailable in demo mode."
         prompt = f"""Explain this SQL query in simple terms:
         
 Original Question: {question}
@@ -160,14 +167,6 @@ async def process_query(request: QueryRequest):
             session_id=session_id
         )
     
-    # Check if Groq client initialized successfully
-    if not groq_client:
-        return QueryResponse(
-            success=False,
-            error="Groq client initialization failed. Running in limited mode.",
-            session_id=session_id
-        )try:
-        # Generate SQL using Groq
         sql, error = generate_sql_with_groq(request.question)
         
         if error: