app.py

import gradio as gr
from langchain.chains import RetrievalQAWithSourcesChain  # Import RetrievalQAWithSourcesChain instead of RetrievalQA
from langchain.llms import HuggingFaceHub  # Import HuggingFaceHub for Jais
from langchain.embeddings import HuggingFaceEmbeddings
import os
import preprocess  # Import the preprocess module
import create_database  # Import the create_database module
from langchain_chroma import Chroma  # Import Chroma from langchain_chroma


# --- Preprocessing and Database Creation ---

# Preprocess data if not already done
if not os.path.exists("db"):  # Check if database exists
    preprocess.preprocess_and_save("./documents", "preprocessed_data.json")  # Update path
    create_database.create_vector_database("preprocessed_data.json", "db")

# --- RAG Pipeline ---

# Load the vector database
embedding_model = HuggingFaceEmbeddings(model_name="sentence-transformers/all-MiniLM-L6-v2")
vector_db = Chroma(persist_directory="db", embedding_function=embedding_model)
retriever = vector_db.as_retriever(search_kwargs={"k": 3})

# Load Jais-13B from Hugging Face
def initialize_llm():
    """Initializes the Hugging Face LLM using the HUGGINGFACEHUB_API_TOKEN environment variable."""
    huggingfacehub_api_token = os.environ.get("HUGGINGFACEHUB_API_TOKEN")
    if not huggingfacehub_api_token:
        raise ValueError("HUGGINGFACEHUB_API_TOKEN environment variable not set.")

    llm = HuggingFaceHub(
        repo_id="jais-foundation/jais-13b-chat",
        huggingfacehub_api_token=huggingfacehub_api_token,
        task="text-generation",
        model_kwargs={'temperature': 0.3, 'max_new_tokens': 512}
    )
    return llm

    
# Create the RetrievalQA chain
# chain_type="stuff" is required in LangChain 0.0.200 or later
qa_chain = RetrievalQAWithSourcesChain.from_chain_type(llm=initialize_llm, chain_type="stuff", retriever=retriever) 

# --- Gradio Interface ---

def chatbot_interface(question):
    result = qa_chain({"question": question})
    # Only return the answer, not the sources
    return result['answer'] 

iface = gr.Interface(
    fn=chatbot_interface,
    inputs="text",
    outputs="text",
    title="Dubai Legislation AI Chatbot"
)

iface.launch()