app_chat.py

import gradio as gr
import requests
import numpy as np
import time
import json
import os

# Import the utilities with proper error handling
try:
    from utils.encoding_input import encode_text
    from utils.retrieve_n_rerank import retrieve_and_rerank
    from utils.sentiment_analysis import get_sentiment
    from utils.coherence_bbscore import coherence_report
    from utils.loading_embeddings import get_vectorstore
    from utils.model_generation import build_messages
except ImportError as e:
    print(f"Import error: {e}")
    print("Make sure you're running from the correct directory and all dependencies are installed.")

API_KEY = os.getenv("API_KEY", "sk-do-8Hjf0liuGQCoPwglilL49xiqrthMECwjGP_kAjPM53OTOFQczPyfPK8xJc")
MODEL = "llama3.3-70b-instruct"

# Global settings for sentiment and coherence analysis
ENABLE_SENTIMENT = True
ENABLE_COHERENCE = True

def chat_response(message, history):
    """
    Generate response for chat interface.
    
    Args:
        message: Current user message
        history: List of [user_message, bot_response] pairs
    """
    
    try:
        # Initialize vectorstore when needed
        vectorstore = get_vectorstore()
        
        # Retrieve and rerank documents
        reranked_results = retrieve_and_rerank(
            query_text=message,
            vectorstore=vectorstore,
            k=50,  # number of initial documents to retrieve
            rerank_model="cross-encoder/ms-marco-MiniLM-L-6-v2",
            top_m=20,  # number of documents to return after reranking
            min_score=0.5,  # minimum score for reranked documents
            only_docs=False  # return both documents and scores
        )
        
        if not reranked_results:
            return "I'm sorry, I couldn't find any relevant information in the policy documents to answer your question. Could you try rephrasing your question or asking about a different topic?"
        
        top_docs = [doc for doc, score in reranked_results]

        # Perform sentiment and coherence analysis if enabled
        sentiment_rollup = get_sentiment(top_docs) if ENABLE_SENTIMENT else {}
        coherence_report_ = coherence_report(reranked_results=top_docs, input_text=message) if ENABLE_COHERENCE else ""

        # Build messages for the LLM, including conversation history
        messages = build_messages_with_history(
            query=message,
            history=history,
            top_docs=top_docs,
            task_mode="verbatim_sentiment",
            sentiment_rollup=sentiment_rollup,
            coherence_report=coherence_report_,
        )

        # Stream response from the API
        response = ""
        for chunk in stream_llm_response(messages):
            response += chunk
            yield response

    except Exception as e:
        error_msg = f"I encountered an error while processing your request: {str(e)}"
        yield error_msg

def build_messages_with_history(query, history, top_docs, task_mode, sentiment_rollup, coherence_report):
    """Build messages including conversation history for better context."""
    
    # System message
    system_msg = (
        "You are a compliance-grade policy analyst assistant specializing in Kenya policy documents. "
        "Your job is to return precise, fact-grounded responses based on the provided policy documents. "
        "Avoid hallucinations. Base everything strictly on the content provided. "
        "Maintain conversation context from previous exchanges when relevant. "
        "If sentiment or coherence analysis is not available, do not mention it in the response."
    )
    
    messages = [{"role": "system", "content": system_msg}]
    
    # Add conversation history (keep last 4 exchanges to maintain context without exceeding limits)
    recent_history = history[-4:] if len(history) > 4 else history
    for user_msg, bot_msg in recent_history:
        messages.append({"role": "user", "content": user_msg})
        messages.append({"role": "assistant", "content": bot_msg})
    
    # Build context from retrieved documents
    context_block = "\n\n".join([
        f"**Source: {getattr(doc, 'metadata', {}).get('source', 'Unknown')} "
        f"(Page {getattr(doc, 'metadata', {}).get('page', 'Unknown')})**\n"
        f"{doc.page_content}\n"
        for doc in top_docs[:10]  # Limit to top 10 docs to avoid token limits
    ])
    
    # Current user query with context
    current_query = f"""
Query: {query}

Based on the following policy documents, please provide:
1) **Quoted Policy Excerpts**: Quote key policy content directly. Cite the source using filename and page.
2) **Analysis**: Explain the policy implications in clear terms.
"""
    
    if sentiment_rollup:
        current_query += f"\n3) **Sentiment Summary**: {sentiment_rollup}"
    
    if coherence_report:
        current_query += f"\n4) **Coherence Assessment**: {coherence_report}"
        
    current_query += f"\n\nContext Sources:\n{context_block}"
    
    messages.append({"role": "user", "content": current_query})
    
    return messages

def stream_llm_response(messages):
    """Stream response from the LLM API."""
    headers = {
        "Authorization": f"Bearer {API_KEY}",
        "Content-Type": "application/json"
    }

    data = {
        "model": MODEL,
        "messages": messages,
        "temperature": 0.2,
        "stream": True,
        "max_tokens": 2000
    }

    try:
        with requests.post("https://inference.do-ai.run/v1/chat/completions", 
                          headers=headers, json=data, stream=True, timeout=30) as r:
            if r.status_code != 200:
                yield f"[ERROR] API returned status {r.status_code}: {r.text}"
                return

            for line in r.iter_lines(decode_unicode=True):
                if not line or line.strip() == "data: [DONE]":
                    continue
                if line.startswith("data: "):
                    line = line[len("data: "):]

                try:
                    chunk = json.loads(line)
                    delta = chunk.get("choices", [{}])[0].get("delta", {}).get("content", "")
                    if delta:
                        yield delta
                        time.sleep(0.01)  # Small delay for smooth streaming
                except json.JSONDecodeError:
                    continue
                except Exception as e:
                    print(f"Streaming error: {e}")
                    continue
                    
    except requests.exceptions.RequestException as e:
        yield f"[ERROR] Network error: {str(e)}"
    except Exception as e:
        yield f"[ERROR] Unexpected error: {str(e)}"

def update_sentiment_setting(enable):
    """Update global sentiment analysis setting."""
    global ENABLE_SENTIMENT
    ENABLE_SENTIMENT = enable
    return f"✅ Sentiment analysis {'enabled' if enable else 'disabled'}"

def update_coherence_setting(enable):
    """Update global coherence analysis setting."""
    global ENABLE_COHERENCE
    ENABLE_COHERENCE = enable
    return f"✅ Coherence analysis {'enabled' if enable else 'disabled'}"

# Create the chat interface
with gr.Blocks(title="Kenya Policy Assistant - Chat", theme=gr.themes.Soft()) as demo:
    gr.Markdown("""
    # 🏛️ Kenya Policy Assistant - Interactive Chat
    Ask questions about Kenya's policies and have a conversation! I can help you understand policy documents with sentiment and coherence analysis.
    """)
    
    with gr.Row():
        with gr.Column(scale=3):
            # Settings row at the top
            with gr.Row():
                sentiment_toggle = gr.Checkbox(
                    label="📊 Sentiment Analysis", 
                    value=True,
                    info="Analyze tone and sentiment of policy documents"
                )
                coherence_toggle = gr.Checkbox(
                    label="🔍 Coherence Analysis", 
                    value=True,
                    info="Check coherence and consistency of retrieved documents"
                )
            
            # Main chat interface
            chatbot = gr.Chatbot(
                height=500,
                bubble_full_width=False,
                show_copy_button=True,
                show_share_button=True,
                avatar_images=("👤", "🤖")
            )
            
            msg = gr.Textbox(
                placeholder="Ask me about Kenya's policies... (e.g., 'What are the renewable energy regulations?')",
                label="Your Question",
                lines=2
            )
            
            with gr.Row():
                submit_btn = gr.Button("📤 Send", variant="primary")
                clear_btn = gr.Button("🗑️ Clear Chat")
        
        with gr.Column(scale=1):
            gr.Markdown("""
            ### 💡 Chat Tips
            - Ask specific questions about Kenya policies
            - Ask follow-up questions based on responses
            - Reference previous answers: *"What does this mean?"*
            - Request elaboration: *"Can you explain more?"*
            
            ### 📝 Example Questions
            - *"What are Kenya's renewable energy policies?"*
            - *"Tell me about water management regulations"*
            - *"What penalties exist for environmental violations?"*
            - *"How does this relate to what you mentioned earlier?"*
            
            ### ⚙️ Analysis Features
            **Sentiment Analysis**: Understands the tone and intent of policy text
            
            **Coherence Analysis**: Checks if retrieved documents are relevant and consistent
            """)
            
            with gr.Accordion("📊 Analysis Status", open=False):
                sentiment_status = gr.Textbox(
                    value="✅ Sentiment analysis enabled",
                    label="Sentiment Status",
                    interactive=False
                )
                coherence_status = gr.Textbox(
                    value="✅ Coherence analysis enabled", 
                    label="Coherence Status",
                    interactive=False
                )

    # Chat functionality
    def respond(message, history):
        if message.strip():
            bot_message = chat_response(message, history)
            history.append([message, ""])
            
            for partial_response in bot_message:
                history[-1][1] = partial_response
                yield history, ""
        else:
            yield history, ""

    submit_btn.click(respond, [msg, chatbot], [chatbot, msg])
    msg.submit(respond, [msg, chatbot], [chatbot, msg])
    clear_btn.click(lambda: ([], ""), outputs=[chatbot, msg])
    
    # Update settings when toggles change
    sentiment_toggle.change(
        fn=update_sentiment_setting,
        inputs=[sentiment_toggle],
        outputs=[sentiment_status]
    )
    
    coherence_toggle.change(
        fn=update_coherence_setting,
        inputs=[coherence_toggle],
        outputs=[coherence_status]
    )

if __name__ == "__main__":
    print("🚀 Starting Kenya Policy Assistant Chat...")
    demo.queue(max_size=20).launch(
        share=True, 
        debug=True,
        server_name="0.0.0.0",
        server_port=7860
    )