import os
import torch
import platform
from colorama import Fore, Style
from transformers import AutoModelForCausalLM, AutoTokenizer
from transformers.generation.utils import GenerationConfig


def init_model():
    print("Initializing model...")
    model_path = "ShengbinYue/DISC-LawLLM"
    model = AutoModelForCausalLM.from_pretrained(
        model_path, torch_dtype=torch.float16, device_map="auto", trust_remote_code=True
    )
    model.generation_config = GenerationConfig.from_pretrained(model_path)
    tokenizer = AutoTokenizer.from_pretrained(
        model_path, use_fast=False, trust_remote_code=True
    )
    return model, tokenizer


def clear_screen():
    if platform.system() == "Windows":
        os.system("cls")
    else:
        os.system("clear")
    print(
        Fore.YELLOW
        + Style.BRIGHT
        + "欢迎使用复旦 DISC-LawLLM，输入进行对话，clear 清空历史，Ctrl+C 中断生成，"
        + "stream 开关流式生成，exit 结束。"
    )
    return []


def main(stream=True):
    model, tokenizer = init_model()

    messages = clear_screen()
    while True:
        prompt = input(Fore.GREEN + Style.BRIGHT + "\n用户：" + Style.NORMAL)
        if prompt.strip() == "exit":
            break
        if prompt.strip() == "clear":
            messages = clear_screen()
            continue
        print(Fore.CYAN + Style.BRIGHT + "\nDISC-LawLLM：" + Style.NORMAL, end="")

        if prompt.strip() == "stream":
            stream = not stream
            print(
                Fore.YELLOW + "({}流式生成)\n".format("开启" if stream else "关闭"),
                end="",
            )
            continue
        messages.append({"role": "user", "content": prompt})

        if stream:
            position = 0
            try:
                for response in model.chat(tokenizer, messages, stream=True):
                    print(response[position:], end="", flush=True)
                    position = len(response)
                    if torch.backends.mps.is_available():
                        torch.mps.empty_cache()
            except KeyboardInterrupt:
                pass
            print()
        else:
            response = model.chat(tokenizer, messages)
            print(response)
            if torch.backends.mps.is_available():
                torch.mps.empty_cache()
        messages.append({"role": "assistant", "content": response})

    print(Style.RESET_ALL)


if __name__ == "__main__":
    main()