import gradio as gr           
import torch
from transformers import AutoTokenizer, AutoModelForCausalLM, BitsAndBytesConfig

base_model_id = "mistralai/Mistral-7B-v0.1"
bnb_config = BitsAndBytesConfig(
    load_in_4bit=True,
    bnb_4bit_use_double_quant=True,
    bnb_4bit_quant_type="nf4",
    bnb_4bit_compute_dtype=torch.bfloat16
)

model = AutoModelForCausalLM.from_pretrained(base_model_id, quantization_config=bnb_config)
base_model = AutoModelForCausalLM.from_pretrained(
    base_model_id,  # Mistral, same as before
    quantization_config=bnb_config,  # Same quantization config as before
    device_map="auto",
    trust_remote_code=True,
    use_auth_token=api_token
)

tokenizer = AutoTokenizer.from_pretrained(base_model_id, trust_remote_code=True)
tokenizer.pad_token = tokenizer.eos_tokentokenizer = AutoTokenizer.from_pretrained("mistralai/Mistral-7B-v0.1")    
tokenizer.padding_side = 'left'      
model = PeftModel.from_pretrained(base_model, "Tonic/mistralmed")
    
class ChatBot:      
    def __init__(self):      
        self.history = []      
    
    def predict(self, input):            
        new_user_input_ids = tokenizer.encode(input + tokenizer.eos_token, return_tensors="pt")            
        flat_history = [item for sublist in self.history for item in sublist]       
        flat_history_tensor = torch.tensor(flat_history).unsqueeze(dim=0)  # convert list to 2-D tensor    
        bot_input_ids = torch.cat([flat_history_tensor, new_user_input_ids], dim=-1) if self.history else new_user_input_ids            
        chat_history_ids = model.generate(bot_input_ids, max_length=2000, pad_token_id=tokenizer.eos_token_id)            
        self.history.append(chat_history_ids[:, bot_input_ids.shape[-1]:].tolist()[0])            
        response = tokenizer.decode(chat_history_ids[:, bot_input_ids.shape[-1]:][0], skip_special_tokens=True)     
        return response      
  
bot = ChatBot() 
  
title = "👋🏻Welcome to Tonic's EZ Chat🚀"    
description = "You can use this Space to test out the current model (MistralMed) or duplicate this Space and use it for any other model on 🤗HuggingFace. Join me on [Discord](https://discord.gg/fpEPNZGsbt) to build together."    
examples = [["What is the boiling point of nitrogen?"]]    
  
iface = gr.Interface(    
    fn=bot.predict,    
    title=title,    
    description=description,    
    examples=examples,    
    inputs="text",    
    outputs="text", 
    theme="ParityError/Anime"
)    
  
iface.launch()