from transformers import MllamaForConditionalGeneration, AutoProcessor, TextIteratorStreamer
from PIL import Image
import requests
import torch
from threading import Thread
import gradio as gr
from gradio import FileData
import time
import spaces
import re
ckpt = "Xkev/Llama-3.2V-11B-cot"
model = MllamaForConditionalGeneration.from_pretrained(ckpt,
    torch_dtype=torch.bfloat16).to("cuda")
processor = AutoProcessor.from_pretrained(ckpt)


@spaces.GPU
def bot_streaming(message, history, max_new_tokens=250):
    
    txt = message["text"]
    ext_buffer = f"{txt}"
    
    messages= [] 
    images = []
    

    for i, msg in enumerate(history): 
        if isinstance(msg[0], tuple):
            messages.append({"role": "user", "content": [{"type": "text", "text": history[i+1][0]}, {"type": "image"}]})
            messages.append({"role": "assistant", "content": [{"type": "text", "text": history[i+1][1]}]})
            images.append(Image.open(msg[0][0]).convert("RGB"))
        elif isinstance(history[i-1], tuple) and isinstance(msg[0], str):
            # messages are already handled
            pass
        elif isinstance(history[i-1][0], str) and isinstance(msg[0], str): # text only turn
            messages.append({"role": "user", "content": [{"type": "text", "text": msg[0]}]})
            messages.append({"role": "assistant", "content": [{"type": "text", "text": msg[1]}]})

    # add current message
    if len(message["files"]) == 1:
        
        if isinstance(message["files"][0], str): # examples
            image = Image.open(message["files"][0]).convert("RGB")
        else: # regular input
            image = Image.open(message["files"][0]["path"]).convert("RGB")
        images.append(image)
        messages.append({"role": "user", "content": [{"type": "text", "text": txt}, {"type": "image"}]})
    else:
        messages.append({"role": "user", "content": [{"type": "text", "text": txt}]})


    texts = processor.apply_chat_template(messages, add_generation_prompt=True)

    if images == []:
        inputs = processor(text=texts, return_tensors="pt").to("cuda")
    else:
        inputs = processor(text=texts, images=images, return_tensors="pt").to("cuda")
        
    streamer = TextIteratorStreamer(processor, skip_special_tokens=True, skip_prompt=True)

    generation_kwargs = dict(inputs, streamer=streamer, max_new_tokens=max_new_tokens)
    generated_text = ""
    
    thread = Thread(target=model.generate, kwargs=generation_kwargs)
    thread.start()
    buffer = ""
    
    for new_text in streamer:
        buffer += new_text
        generated_text_without_prompt = buffer
        time.sleep(0.01)
    
        buffer = re.sub(r"<(\w+)>", r"(Here begins the \1 stage)", buffer)  
        buffer = re.sub(r"</(\w+)>", r"(Here ends the \1 stage)", buffer)  
    
        yield buffer


demo = gr.ChatInterface(fn=bot_streaming, title="LLaVA-CoT",
      textbox=gr.MultimodalTextbox(), 
      additional_inputs = [gr.Slider(
              minimum=512,
              maximum=1024,
              value=512,
              step=1,
              label="Maximum number of new tokens to generate",
          )
        ],
      examples=[[{"text": "What is on the flower?", "files": ["./Example1.webp"]},512],
                [{"text": "How to make this pastry?", "files": ["./Example2.png"]},512]],
      cache_examples=False,
      description="Upload an image, and start chatting about it. To learn more about LLaVA-CoT, visit [our GitHub page](https://github.com/PKU-YuanGroup/LLaVA-CoT). Note: Since Gradio currently does not support displaying the special markings in the output, we have replaced it with the expression (Here begins the X phase).",
      stop_btn="Stop Generation", 
      fill_height=True,
    multimodal=True)
    
demo.launch(debug=True)