app.py

import os
import spaces
import gradio as gr
from huggingface_hub import InferenceClient, login
import time
import traceback
from transformers import AutoModelForCausalLM, AutoTokenizer, BitsAndBytesConfig
from peft import PeftModel, PeftConfig
import bitsandbytes
import torch


@spaces.GPU  # Forces GPU allocation before execution
def force_gpu_allocation():
    pass  # Dummy function to trigger GPU setup

# Base model (LLaMA 3.1 8B) from Meta
base_model_name = "meta-llama/Llama-3.1-8B"

# Your fine-tuned LoRA adapter (uploaded to Hugging Face)
lora_model_name = "starnernj/Early-Christian-Church-Fathers-LLaMA-3.1-Fine-Tuned"

# Login because LLaMA 3.1 8B is a gated model
login(token=os.getenv("HuggingFaceFineGrainedReadToken"))

# Enable 4-bit Quantization with BitsAndBytes
quantization_config = BitsAndBytesConfig(
    load_in_4bit=True,  # ✅ Enables 4-bit quantization for memory efficiency
    bnb_4bit_compute_dtype=torch.float16,  # ✅ Uses float16 for performance
    bnb_4bit_use_double_quant=True,  # ✅ Optimizes quantization
    bnb_4bit_quant_type="nf4"  # ✅ Normalized Float-4 for better accuracy
)

base_model = AutoModelForCausalLM.from_pretrained(
    base_model_name,
    quantization_config=quantization_config,
    device_map="auto"
)

# Load tokenizer
tokenizer = AutoTokenizer.from_pretrained(base_model_name)

# Load LoRA Adapter
print("Loading LoRA adapter...")
model = PeftModel.from_pretrained(base_model, lora_model_name)

# Function to generate responses
def chatbot_response(user_input):
    try:
        inputs = tokenizer(user_input, return_tensors="pt").to("cuda")
        outputs = model.generate(**inputs, max_length=200)
        return tokenizer.decode(outputs[0], skip_special_tokens=True)
    except Exception as e:
        error_message = f"AssertionError: {str(e)}\n{traceback.format_exc()}"
        print(error_message)  # ✅ Logs detailed error messages
        return "An error occurred. Check the logs for details."


# Launch the Gradio chatbot
interface = gr.Interface(
    fn=chatbot_response,
    inputs=gr.Textbox(lines=2, placeholder="Ask me about the Christian Church Fathers..."),
    outputs="text",
    title="Early Christian Church Fathers Fine-Tuned LLaMA 3.1 8B with LoRA",
    description="A chatbot using a fine-tuned LoRA adapter on LLaMA 3.1 8B, tuned on thousands of writings of the early Christian Church Fathers.",
)

if __name__ == "__main__":
    interface.launch()