app.py

import gradio as gr
import os
import uuid
import threading
import pandas as pd
import torch
from langchain.document_loaders import CSVLoader
from langchain.embeddings import HuggingFaceEmbeddings
from langchain.vectorstores import FAISS
from langchain.llms import HuggingFacePipeline
from langchain.chains import LLMChain
from transformers import AutoTokenizer, AutoModelForCausalLM, T5Tokenizer, T5ForConditionalGeneration, pipeline
from langchain.prompts import PromptTemplate
import time

# Global model cache
MODEL_CACHE = {
    "model": None,
    "tokenizer": None,
    "init_lock": threading.Lock(),
    "model_name": None
}

# Create directories for user data
os.makedirs("user_data", exist_ok=True)

# Model configuration dictionary
MODEL_CONFIG = {
    "Llama 2 Chat": {
        "name": "TheBloke/Llama-2-7B-Chat-GGUF",
        "description": "Llama 2 7B Chat model with good general performance",
        "dtype": torch.float16 if torch.cuda.is_available() else torch.float32
    },
    "TinyLlama Chat": {
        "name": "TheBloke/TinyLlama-1.1B-Chat-v1.0-GGUF",
        "description": "Compact 1.1B parameter model, fast but less powerful",
        "dtype": torch.float16 if torch.cuda.is_available() else torch.float32
    },
    "Mistral Instruct": {
        "name": "TheBloke/Mistral-7B-Instruct-v0.2-GGUF",
        "description": "7B instruction-tuned model with excellent reasoning",
        "dtype": torch.float16 if torch.cuda.is_available() else torch.float32
    },
    "Phi-4 Mini Instruct": {
        "name": "microsoft/Phi-4-mini-instruct",
        "description": "Compact Microsoft model with strong instruction following",
        "dtype": torch.float16 if torch.cuda.is_available() else torch.float32
    },
    "DeepSeek Coder Instruct": {
        "name": "deepseek-ai/deepseek-coder-1.3b-instruct",
        "description": "1.3B model specialized for code understanding",
        "dtype": torch.float16 if torch.cuda.is_available() else torch.float32
    },
    "DeepSeek Lite Chat": {
        "name": "deepseek-ai/DeepSeek-V2-Lite-Chat",
        "description": "Light but powerful chat model from DeepSeek",
        "dtype": torch.float16 if torch.cuda.is_available() else torch.float32
    },
    "Qwen2.5 Coder Instruct": {
        "name": "Qwen/Qwen2.5-Coder-3B-Instruct-GGUF",
        "description": "3B model specialized for code and technical applications",
        "dtype": torch.float16 if torch.cuda.is_available() else torch.float32
    },
    "DeepSeek Distill Qwen": {
        "name": "deepseek-ai/DeepSeek-R1-Distill-Qwen-1.5B",
        "description": "1.5B distilled model with good balance of speed and quality",
        "dtype": torch.float16 if torch.cuda.is_available() else torch.float32
    },
    "Flan T5 Small": {
        "name": "google/flan-t5-small",
        "description": "Lightweight T5 model optimized for instruction following",
        "dtype": torch.float16 if torch.cuda.is_available() else torch.float32,
        "is_t5": True
    }
}

def initialize_model_once(model_key):
    """Initialize the model once and cache it"""
    with MODEL_CACHE["init_lock"]:
        current_model = MODEL_CACHE["model_name"]
        if MODEL_CACHE["model"] is None or current_model != model_key:
            # Clear previous model from memory if any
            if MODEL_CACHE["model"] is not None:
                del MODEL_CACHE["model"]
                del MODEL_CACHE["tokenizer"]
                torch.cuda.empty_cache() if torch.cuda.is_available() else None
                
            model_info = MODEL_CONFIG[model_key]
            model_name = model_info["name"]
            MODEL_CACHE["model_name"] = model_key
            
            # Handle T5 models separately
            if model_info.get("is_t5", False):
                MODEL_CACHE["tokenizer"] = T5Tokenizer.from_pretrained(model_name)
                MODEL_CACHE["model"] = T5ForConditionalGeneration.from_pretrained(
                    model_name,
                    torch_dtype=model_info["dtype"],
                    device_map="auto",
                    low_cpu_mem_usage=True
                )
            else:
                # Load tokenizer and model with appropriate configuration
                MODEL_CACHE["tokenizer"] = AutoTokenizer.from_pretrained(model_name)
                MODEL_CACHE["model"] = AutoModelForCausalLM.from_pretrained(
                    model_name,
                    torch_dtype=model_info["dtype"],
                    device_map="auto",
                    low_cpu_mem_usage=True,
                    trust_remote_code=True
                )

    return MODEL_CACHE["tokenizer"], MODEL_CACHE["model"], model_info.get("is_t5", False)

def create_llm_pipeline(model_key):
    """Create a new pipeline using the specified model"""
    tokenizer, model, is_t5 = initialize_model_once(model_key)

    # Create appropriate pipeline based on model type
    if is_t5:
        pipe = pipeline(
            "text2text-generation",
            model=model,
            tokenizer=tokenizer,
            max_new_tokens=256,
            temperature=0.3,
            top_p=0.9,
            return_full_text=False,
        )
    else:
        pipe = pipeline(
            "text-generation",
            model=model,
            tokenizer=tokenizer,
            max_new_tokens=256,
            temperature=0.3,
            top_p=0.9,
            top_k=30,
            repetition_penalty=1.2,
            return_full_text=False,
        )

    # Wrap pipeline in HuggingFacePipeline for LangChain compatibility
    return HuggingFacePipeline(pipeline=pipe)

def create_conversational_chain(db, file_path, model_key):
    llm = create_llm_pipeline(model_key)
    
    # Load the file into pandas to enable code execution for data analysis
    df = pd.read_csv(file_path)
    
    # Create improved prompt template that focuses on direct answers, not code
    template = """
    Berikut ini adalah informasi tentang file CSV:
    
    Kolom-kolom dalam file: {columns}
    
    Beberapa baris pertama:
    {sample_data}
    
    Konteks tambahan dari vector database:
    {context}
    
    Pertanyaan: {question}
    
    INSTRUKSI PENTING:
    1. Jangan tampilkan kode Python, berikan jawaban langsung dalam Bahasa Indonesia.
    2. Jika pertanyaan terkait statistik data (rata-rata, maksimum dll), lakukan perhitungan dan berikan hasilnya.
    3. Jawaban harus singkat, jelas dan akurat berdasarkan data yang ada.
    4. Gunakan format yang sesuai untuk angka (desimal 2 digit untuk nilai non-integer).
    5. Jangan menyebutkan proses perhitungan, fokus pada hasil akhir.
    
    Jawaban:
    """
    
    PROMPT = PromptTemplate(
        template=template,
        input_variables=["columns", "sample_data", "context", "question"]
    )
    
    # Create retriever
    retriever = db.as_retriever(search_kwargs={"k": 3})  # Reduced k for better performance
    
    # Process query with better error handling
    def process_query(query, chat_history):
        try:
            # Get information from dataframe for context
            columns_str = ", ".join(df.columns.tolist())
            sample_data = df.head(2).to_string()  # Reduced to 2 rows for performance
            
            # Get context from vector database
            docs = retriever.get_relevant_documents(query)
            context = "\n\n".join([doc.page_content for doc in docs])
            
            # Dynamically calculate answers for common statistical queries
            def preprocess_query():
                query_lower = query.lower()
                result = None
                
                # Handle statistical queries directly
                if "rata-rata" in query_lower or "mean" in query_lower or "average" in query_lower:
                    for col in df.columns:
                        if col.lower() in query_lower and pd.api.types.is_numeric_dtype(df[col]):
                            try:
                                result = f"Rata-rata {col} adalah {df[col].mean():.2f}"
                            except:
                                pass
                
                elif "maksimum" in query_lower or "max" in query_lower or "tertinggi" in query_lower:
                    for col in df.columns:
                        if col.lower() in query_lower and pd.api.types.is_numeric_dtype(df[col]):
                            try:
                                result = f"Nilai maksimum {col} adalah {df[col].max():.2f}"
                            except:
                                pass
                
                elif "minimum" in query_lower or "min" in query_lower or "terendah" in query_lower:
                    for col in df.columns:
                        if col.lower() in query_lower and pd.api.types.is_numeric_dtype(df[col]):
                            try:
                                result = f"Nilai minimum {col} adalah {df[col].min():.2f}"
                            except:
                                pass
                
                elif "total" in query_lower or "jumlah" in query_lower or "sum" in query_lower:
                    for col in df.columns:
                        if col.lower() in query_lower and pd.api.types.is_numeric_dtype(df[col]):
                            try:
                                result = f"Total {col} adalah {df[col].sum():.2f}"
                            except:
                                pass
                
                elif "baris" in query_lower or "jumlah data" in query_lower or "row" in query_lower:
                    result = f"Jumlah baris data adalah {len(df)}"
                
                elif "kolom" in query_lower or "field" in query_lower:
                    if "nama" in query_lower or "list" in query_lower or "sebutkan" in query_lower:
                        result = f"Kolom dalam data: {', '.join(df.columns.tolist())}"
                
                return result
            
            # Try direct calculation first
            direct_answer = preprocess_query()
            if direct_answer:
                return {"answer": direct_answer}
            
            # If no direct calculation, use the LLM
            chain = LLMChain(llm=llm, prompt=PROMPT)
            raw_result = chain.run(
                columns=columns_str,
                sample_data=sample_data,
                context=context,
                question=query
            )
            
            # Clean the result
            cleaned_result = raw_result.strip()
            
            # If result is empty after cleaning, use a fallback
            if not cleaned_result:
                return {"answer": "Tidak dapat memproses jawaban. Silakan coba pertanyaan lain."}
                
            return {"answer": cleaned_result}
        except Exception as e:
            import traceback
            print(f"Error in process_query: {str(e)}")
            print(traceback.format_exc())
            return {"answer": f"Terjadi kesalahan saat memproses pertanyaan: {str(e)}"}
    
    return process_query

class ChatBot:
    def __init__(self, session_id, model_key="DeepSeek Coder Instruct"):
        self.session_id = session_id
        self.chat_history = []
        self.chain = None
        self.user_dir = f"user_data/{session_id}"
        self.csv_file_path = None
        self.model_key = model_key
        os.makedirs(self.user_dir, exist_ok=True)

    def process_file(self, file, model_key=None):
        if model_key:
            self.model_key = model_key
            
        if file is None:
            return "Mohon upload file CSV terlebih dahulu."

        try:
            # Handle file from Gradio
            file_path = file.name if hasattr(file, 'name') else str(file)
            self.csv_file_path = file_path

            # Copy to user directory
            user_file_path = f"{self.user_dir}/uploaded.csv"

            # Verify the CSV can be loaded
            try:
                df = pd.read_csv(file_path)
                print(f"CSV verified: {df.shape[0]} rows, {len(df.columns)} columns")

                # Save a copy in user directory
                df.to_csv(user_file_path, index=False)
                self.csv_file_path = user_file_path
            except Exception as e:
                return f"Error membaca CSV: {str(e)}"

            # Load document with reduced chunk size for better memory usage
            try:
                loader = CSVLoader(file_path=file_path, encoding="utf-8", csv_args={
                    'delimiter': ','})
                data = loader.load()
                print(f"Documents loaded: {len(data)}")
            except Exception as e:
                return f"Error loading documents: {str(e)}"

            # Create vector database with optimized settings
            try:
                db_path = f"{self.user_dir}/db_faiss"
                
                # Use CPU-friendly embeddings with smaller dimensions
                embeddings = HuggingFaceEmbeddings(
                    model_name='sentence-transformers/all-MiniLM-L6-v2',
                    model_kwargs={'device': 'cpu'}
                )

                db = FAISS.from_documents(data, embeddings)
                db.save_local(db_path)
                print(f"Vector database created at {db_path}")
            except Exception as e:
                return f"Error creating vector database: {str(e)}"

            # Create custom chain
            try:
                self.chain = create_conversational_chain(db, self.csv_file_path, self.model_key)
                print(f"Chain created successfully using model: {self.model_key}")
            except Exception as e:
                return f"Error creating chain: {str(e)}"

            # Add basic file info to chat history for context
            file_info = f"CSV berhasil dimuat dengan {df.shape[0]} baris dan {len(df.columns)} kolom menggunakan model {self.model_key}. Kolom: {', '.join(df.columns.tolist())}"
            self.chat_history.append(("System", file_info))

            return f"File CSV berhasil diproses dengan model {self.model_key}! Anda dapat mulai chat dengan model untuk analisis data."
        except Exception as e:
            import traceback
            print(traceback.format_exc())
            return f"Error pemrosesan file: {str(e)}"

    def change_model(self, model_key):
        """Change the model being used and recreate the chain if necessary"""
        if model_key == self.model_key:
            return f"Model {model_key} sudah digunakan."
            
        self.model_key = model_key
        
        # If we have an active session with a file already loaded, recreate the chain
        if self.csv_file_path:
            try:
                # Load existing database
                db_path = f"{self.user_dir}/db_faiss"
                embeddings = HuggingFaceEmbeddings(
                    model_name='sentence-transformers/all-MiniLM-L6-v2',
                    model_kwargs={'device': 'cpu'}
                )
                db = FAISS.load_local(db_path, embeddings)
                
                # Create new chain with the selected model
                self.chain = create_conversational_chain(db, self.csv_file_path, self.model_key)
                
                return f"Model berhasil diubah ke {model_key}."
            except Exception as e:
                return f"Error mengubah model: {str(e)}"
        else:
            return f"Model diubah ke {model_key}. Silakan upload file CSV untuk memulai."

    def chat(self, message, history):
        if self.chain is None:
            return "Mohon upload file CSV terlebih dahulu."

        try:
            # Process the question with the chain
            result = self.chain(message, self.chat_history)

            # Get the answer with fallback
            answer = result.get("answer", "Maaf, tidak dapat menghasilkan jawaban. Silakan coba pertanyaan lain.")

            # Ensure we never return empty
            if not answer or answer.strip() == "":
                answer = "Maaf, tidak dapat menghasilkan jawaban yang sesuai. Silakan coba pertanyaan lain."
            
            # Update internal chat history
            self.chat_history.append((message, answer))

            # Return just the answer for Gradio
            return answer
        except Exception as e:
            import traceback
            print(traceback.format_exc())
            return f"Error: {str(e)}"

# UI Code
def create_gradio_interface():
    with gr.Blocks(title="Chat with CSV using AI Models") as interface:
        session_id = gr.State(lambda: str(uuid.uuid4()))
        chatbot_state = gr.State(lambda: None)
        
        # Get model choices
        model_choices = list(MODEL_CONFIG.keys())
        default_model = "DeepSeek Coder Instruct"  # Default model

        gr.HTML("<h1 style='text-align: center;'>Chat with CSV using AI Models</h1>")
        gr.HTML("<h3 style='text-align: center;'>Asisten analisis CSV untuk berbagai kebutuhan</h3>")

        with gr.Row():
            with gr.Column(scale=1):
                file_input = gr.File(
                    label="Upload CSV Anda",
                    file_types=[".csv"]
                )
                
                # Model selection accordion BEFORE process button
                with gr.Accordion("Pilih Model AI", open=True):
                    model_dropdown = gr.Dropdown(
                        label="Model",
                        choices=model_choices,
                        value=default_model
                    )
                    model_info = gr.Markdown(
                        value=f"**{default_model}**: {MODEL_CONFIG[default_model]['description']}"
                    )
                
                # Process button AFTER the accordion
                process_button = gr.Button("Proses CSV")

            with gr.Column(scale=2):
                chatbot_interface = gr.Chatbot(
                    label="Riwayat Chat",
                    height=400
                )
                message_input = gr.Textbox(
                    label="Ketik pesan Anda",
                    placeholder="Tanyakan tentang data CSV Anda...",
                    lines=2
                )
                submit_button = gr.Button("Kirim")
                clear_button = gr.Button("Bersihkan Chat")

        # Update model info when selection changes
        def update_model_info(model_key):
            return f"**{model_key}**: {MODEL_CONFIG[model_key]['description']}"
            
        model_dropdown.change(
            fn=update_model_info,
            inputs=[model_dropdown],
            outputs=[model_info]
        )
        
        # Process file handler
        def handle_process_file(file, model_key, sess_id):
            chatbot = ChatBot(sess_id, model_key)
            result = chatbot.process_file(file)
            return chatbot, [(None, result)]

        process_button.click(
            fn=handle_process_file,
            inputs=[file_input, model_dropdown, session_id],
            outputs=[chatbot_state, chatbot_interface]
        )

        # Change model handler
        def handle_model_change(model_key, chatbot, sess_id):
            if chatbot is None:
                chatbot = ChatBot(sess_id, model_key)
                return chatbot, [(None, f"Model diatur ke {model_key}. Silakan upload file CSV.")]
            
            result = chatbot.change_model(model_key)
            return chatbot, chatbot.chat_history + [(None, result)]
            
        model_dropdown.change(
            fn=handle_model_change,
            inputs=[model_dropdown, chatbot_state, session_id],
            outputs=[chatbot_state, chatbot_interface]
        )

        # Chat handlers
        def user_message_submitted(message, history, chatbot, sess_id):
            history = history + [(message, None)]
            return history, "", chatbot, sess_id

        def bot_response(history, chatbot, sess_id):
            if chatbot is None:
                chatbot = ChatBot(sess_id)
                history[-1] = (history[-1][0], "Mohon upload file CSV terlebih dahulu.")
                return chatbot, history

            user_message = history[-1][0]
            response = chatbot.chat(user_message, history[:-1])
            history[-1] = (user_message, response)
            return chatbot, history

        submit_button.click(
            fn=user_message_submitted,
            inputs=[message_input, chatbot_interface, chatbot_state, session_id],
            outputs=[chatbot_interface, message_input, chatbot_state, session_id]
        ).then(
            fn=bot_response,
            inputs=[chatbot_interface, chatbot_state, session_id],
            outputs=[chatbot_state, chatbot_interface]
        )

        message_input.submit(
            fn=user_message_submitted,
            inputs=[message_input, chatbot_interface, chatbot_state, session_id],
            outputs=[chatbot_interface, message_input, chatbot_state, session_id]
        ).then(
            fn=bot_response,
            inputs=[chatbot_interface, chatbot_state, session_id],
            outputs=[chatbot_state, chatbot_interface]
        )

        # Clear chat handler
        def handle_clear_chat(chatbot):
            if chatbot is not None:
                chatbot.chat_history = []
            return chatbot, []

        clear_button.click(
            fn=handle_clear_chat,
            inputs=[chatbot_state],
            outputs=[chatbot_state, chatbot_interface]
        )

    return interface

# Launch the interface
demo = create_gradio_interface()
demo.launch(share=True)