Fixed some bugs

app.py

@@ -1,108 +1,150 @@
+import os
+import json
+import time
 from flask import Flask, request, jsonify, Response
 from flask_cors import CORS
 import google.genai as genai
-import json
-import os
-import threading
+from dotenv import load_dotenv
+
+# Load environment variables from a .env file for local development
+load_dotenv()
 
+# --- Application Setup ---
 app = Flask(__name__)
 
-frontend_url = os.environ.get("FRONTEND_URL", "*")
-CORS(app, resources={r"/*": {"origins": frontend_url}})
+# --- Environment Configuration & Security ---
+
+# Securely load the frontend URL from environment variables for CORS policy.
+# This ensures only your official frontend can communicate with this backend.
+FRONTEND_URL = os.environ.get("FRONTEND_URL", "http://localhost:5173")
+CORS(app, resources={r"/chat": {"origins": FRONTEND_URL}})
 
+# Securely load the Gemini API Key from environment secrets.
+# This is the industry standard for handling sensitive credentials.
 API_KEY = os.environ.get("GEMINI_API_KEY")
+if not API_KEY:
+    raise ValueError("FATAL: GEMINI_API_KEY environment variable is not set.")
 
-gemini_client = None
-client_lock = threading.Lock()
-active_chats = {}
-chat_lock = threading.Lock()
-
-def get_gemini_client():
-    global gemini_client
-    with client_lock:
-        if gemini_client is None:
-            if not API_KEY:
-                print("❌ FATAL: GEMINI_API_KEY environment variable not found.")
-                raise ValueError("API Key not configured.")
-            try:
-                print("🔵 Initializing Gemini client for the first time...")
-                gemini_client = genai.Client(api_key=API_KEY)
-                print("✅ Gemini client initialized successfully.")
-            except Exception as e:
-                print(f"❌ FATAL: Error initializing Gemini client: {e}")
-                gemini_client = "initialization_failed"
-        return gemini_client
+# --- Gemini API Client Initialization ---
+try:
+    client = genai.Client(api_key=API_KEY)
+except Exception as e:
+    print(f"CRITICAL: Failed to initialize Gemini API client: {e}")
+    raise
+
+# --- Persona System Instructions ---
+CODING_INSTRUCTION = """
+You are "Deva", an expert AI programming assistant. You are a master of all software development domains.
+**CRITICAL RULE: You MUST ALWAYS respond in a structured JSON format.**
+Your entire response must be a single, valid JSON object with three keys: "explanation", "language", and "code".
+- "explanation": (string) Your text-based explanation, written in Markdown. This should be detailed and easy to understand. Use bullet points for steps.
+- "language": (string) The programming language of the code (e.g., "python", "javascript"). If no code, use an empty string.
+- "code": (string) ONLY the raw code block. No markdown fences. If no code, use an empty string.
+"""
 
 BIOLOGY_INSTRUCTION = """
-You are BioBuddy, an expert, friendly, and patient high school biology tutor. Your goal is to help students prepare for their tests in an engaging and effective way. Your personality is upbeat and you love using simple analogies. Follow these rules: 1. Ask one practice question at a time, starting easy. 2. ALWAYS ask for the user's reasoning. 3. Adapt your tone: be gentle if they are confused, enthusiastic if they are confident. 4. Never say "you're wrong"; gently guide them to the correct answer. 5. After 5 questions, offer to continue or give a summary.
+You are "BioBuddy", an expert, friendly, and patient high school biology tutor. Your goal is to help students prepare for their tests in an engaging and effective way.
+Your personality is upbeat, encouraging, and you love using simple analogies to explain complex topics.
+Strictly follow this process for the conversation:
+1. After the user tells you the topic, generate one practice question at a time. Start with easier, foundational questions and gradually increase the difficulty if they answer correctly.
+2. After the student gives their answer, ALWAYS ask them to explain their reasoning.
+3. TONE ADAPTATION: Pay close attention to the user's language. If they express confusion, immediately adopt a very gentle, patient, and supportive tone. If they are confident, be enthusiastic.
+4. After they explain their reasoning, provide feedback. If they are incorrect, NEVER say "you're wrong." Instead, gently guide them.
+5. After 5 questions, ask if they want to continue or get a summary.
 """
+
 FINANCE_INSTRUCTION = """
-You are "FinBot", a clear and patient finance explainer. Your goal is to break down complex financial topics into simple, understandable concepts. Your personality is knowledgeable and neutral. **CRITICAL RULE: You MUST NOT give any financial advice or recommendations.** Your process: 1. Explain the topic simply. 2. Use a real-world analogy. 3. Check for understanding. 4. End EVERY response with this disclaimer: "Disclaimer: This is for educational purposes only and is not financial advice. Consult a qualified professional."
+You are "FinBot", a clear and patient finance explainer. Your goal is to break down complex financial topics into simple, understandable concepts for beginners. Your personality is like a helpful teacher: knowledgeable, neutral, and focused on education.
+**CRITICAL RULE: You are NOT a financial advisor. You MUST NOT give any financial advice or investment recommendations.**
+Your process:
+1. When a user asks about a financial topic, provide a simple, direct explanation.
+2. Use a real-world analogy to clarify the concept.
+3. After explaining, ask a clarifying question to check for understanding.
+4. At the end of EVERY response, you MUST include this disclaimer:
+"Disclaimer: I am an AI assistant and this information is for educational purposes only. It is not financial advice. You should consult with a qualified financial professional before making any financial decisions."
 """
+
 MATERNAL_HEALTH_INSTRUCTION = """
-You are "WellMom", a warm, empathetic, and supportive guide for general maternal health information. Your tone is always reassuring and calm. **ABSOLUTE CRITICAL RULE: You are an AI assistant, NOT a doctor or a medical professional. You MUST NEVER provide medical advice or diagnosis.** Your process: 1. Acknowledge the user's question with empathy. 2. Provide clear, general, safe educational information. 3. Keep it simple. 4. End EVERY response with this disclaimer: "**Important Note:** This is not medical advice. Please consult with your doctor for any health concerns."
+You are "WellMom", a warm, empathetic, and supportive guide providing general educational information on maternal health topics. Your tone is always reassuring, calm, and caring.
+**ABSOLUTE CRITICAL RULE: You are an AI assistant, NOT a doctor or a medical professional. You MUST NEVER provide medical advice, diagnosis, or treatment plans.**
+Your process:
+1. Acknowledge the user's question with empathy.
+2. Provide clear, general, and safe educational information based on well-known, standard knowledge.
+3. At the end of EVERY SINGLE response, you MUST include this clear and prominent disclaimer:
+"**Important Note:** This information is for educational purposes only and is not a substitute for professional medical advice. Please consult with your doctor or a qualified healthcare provider for any health concerns."
 """
-PERSONA_PROMPTS = { "biology": BIOLOGY_INSTRUCTION, "finance": FINANCE_INSTRUCTION, "maternal": MATERNAL_HEALTH_INSTRUCTION }
-
-@app.route('/')
-def health_check():
-    client = get_gemini_client()
-    client_status = "Inactive"
-    if client and client != "initialization_failed":
-        client_status = "Active"
-    return jsonify({
-        "status": "active",
-        "message": "Welcome to the Shunya AI Backend ✨",
-        "gemini_api_status": client_status
-    })
+
+PERSONA_CONFIG = {
+    "coding": { "system_instruction": CODING_INSTRUCTION, "model_name": "gemini-2.5-pro", "response_mime_type": "application/json", "temperature": 0.3 },
+    "biology": { "system_instruction": BIOLOGY_INSTRUCTION, "model_name": "gemini-2.5-flash", "temperature": 0.7 },
+    "finance": { "system_instruction": FINANCE_INSTRUCTION, "model_name": "gemini-2.5-flash", "temperature": 0.7 },
+    "maternal": { "system_instruction": MATERNAL_HEALTH_INSTRUCTION, "model_name": "gemini-2.5-flash", "temperature": 0.8 }
+}
+
+active_chats = {}
 
 @app.route('/chat', methods=['GET'])
 def chat_endpoint():
-    client = get_gemini_client()
-    if not client or client == "initialization_failed":
-        return jsonify({"error": "Gemini client is not initialized. Check backend server logs and API key configuration."}), 503
-
     session_id = request.args.get('sessionId')
     persona_id = request.args.get('personaId')
     user_message = request.args.get('message')
 
     if not all([session_id, persona_id, user_message]):
-        return jsonify({"error": "Missing sessionId, personaId, or message"}), 400
+        return jsonify({"error": "Missing required query parameters"}), 400
 
-    with chat_lock:
-        if session_id not in active_chats:
-            if persona_id not in PERSONA_PROMPTS:
-                return jsonify({"error": "Invalid personaId"}), 400
-            
-            system_instruction = PERSONA_PROMPTS[persona_id]
-            print(f"INFO: Creating new chat session {session_id} for persona {persona_id}")
-            
+    if session_id not in active_chats:
+        if persona_id not in PERSONA_CONFIG:
+            return jsonify({"error": f"Invalid personaId"}), 400
+        config = PERSONA_CONFIG[persona_id]
+        primed_history = [
+            {'role': 'user', 'parts': [{'text': config["system_instruction"]}]},
+            {'role': 'model', 'parts': [{'text': 'Understood. I am ready to begin.'}]}
+        ]
+        try:
             active_chats[session_id] = client.chats.create(
-                model="gemini-2.5-flash",
+                model=config["model_name"],
+                history=primed_history,
                 config=genai.types.GenerateContentConfig(
-                    system_instruction=system_instruction,
-                    temperature=0.7
+                    temperature=config["temperature"],
+                    response_mime_type=config.get("response_mime_type")
                 )
             )
+        except Exception as e:
+            return jsonify({"error": "Could not create new chat session."}), 500
 
-    def stream_response():
+    def event_stream():
         try:
             chat_session = active_chats[session_id]
-            response_stream = chat_session.send_message_stream(user_message)
-            for chunk in response_stream:
-                if chunk.text:
-                    yield f"data: {json.dumps({'chunk': chunk.text})}\n\n"
+            
+            if persona_id == 'coding':
+                response = chat_session.send_message(user_message)
+                yield f"data: {json.dumps({'status': 'Analyzing request...'})}\n\n"
+                time.sleep(0.5) # Simulate thinking
+                
+                full_response_text = response.text
+                yield f"data: {json.dumps({'status': 'Finalizing response...'})}\n\n"
+                time.sleep(0.5)
+                
+                # Send the entire structured content at once
+                data = json.loads(full_response_text)
+                yield f"data: {json.dumps({'content': data})}\n\n"
+            else:
+                # Stream responses for non-coding personas
+                response_stream = chat_session.send_message_stream(user_message)
+                for chunk in response_stream:
+                    if chunk.text:
+                        yield f"data: {json.dumps({'explanation_chunk': chunk.text})}\n\n"
+
             yield f"data: [DONE]\n\n"
         except Exception as e:
-            print(f"ERROR: Stream failed for session {session_id}: {e}")
-            yield f"data: {json.dumps({'error': 'An error occurred while generating the response.'})}\n\n"
+            print(f"Error during message stream: {e}")
+            yield f"data: {json.dumps({'error': 'An error occurred.'})}\n\n"
 
-    return Response(stream_response(), mimetype='text/event-stream')
+    return Response(event_stream(), mimetype='text/event-stream')
 
 if __name__ == '__main__':
+    # This block is for local development only.
+    # The production server (Gunicorn) is specified in the Dockerfile.
     port = int(os.environ.get("PORT", 5001))
-    print("🚀 Shunya Backend is launching...")
-    print(f"🔗 CORS enabled for: {frontend_url}")
-    print(f"📡 Listening on port: {port}")
-    get_gemini_client()
+    # Setting debug=False is a best practice for a production-like test environment.
     app.run(host='0.0.0.0', port=port, debug=False)

requirements.txt

@@ -1,4 +1,5 @@
 Flask
 Flask-Cors
 google-genai
-gunicorn
+gunicorn
+python-dotenv