import os
from typing import Tuple

import streamlit as st

import torch

import transformers
import tokenizers

from sampling import CAIFSampler, TopKWithTemperatureSampler
from generator import Generator

device = "cuda" if torch.cuda.is_available() else "cpu"


def main():
    st.subheader(
        'Эта демонстрация позволяет поэксперементировать с моделями, которые оценивают, насколько предлагаемый ответ подходит к контексту диалога.')
    cls_model_name = st.selectbox(
        'Выберите модель классификации',
        ('tinkoff-ai/response-quality-classifier-tiny', 'tinkoff-ai/response-quality-classifier-base',
         'tinkoff-ai/response-quality-classifier-large')
    )
    lm_model_name = st.selectbox(
        'Выберите языковую модель',
        ('sberbank-ai/rugpt3small_based_on_gpt2',)
    )
    prompt = st.text_input("Начало текста:", "Привет")
    auth_token = os.environ.get('TOKEN') or True
    with st.spinner('Running inference...'):
        text = inference(lm_model_name=lm_model_name, cls_model_name=cls_model_name, prompt=prompt)
    st.text_area(text)




@st.cache(hash_funcs={str: lambda lm_model_name: hash(lm_model_name)}, allow_output_mutation=True)
def load_generator(lm_model_name: str) -> Generator:
    with st.spinner('Loading language model...'):
        generator = Generator(lm_model_name=lm_model_name, device=device)
        return generator


def load_sampler(cls_model_name, lm_tokenizer):
    with st.spinner('Loading classifier model...'):
        sampler = CAIFSampler(classifier_name=cls_model_name, lm_tokenizer=lm_tokenizer, device=device)
        return sampler


@st.cache
def inference(lm_model_name: str, cls_model_name: str, prompt: str, fp16: bool = True) -> str:
    generator = load_generator(lm_model_name=lm_model_name)
    lm_tokenizer = transformers.AutoTokenizer.from_pretrained(lm_model_name)
    caif_sampler = load_sampler(cls_model_name=cls_model_name, lm_tokenizer=lm_tokenizer)
    generator.set_caif_sampler(caif_sampler)
    ordinary_sampler = TopKWithTemperatureSampler()
    kwargs = {
        "top_k": 20,
        "temperature": 1.0,
        "top_k_classifier": 100,
        "classifier_weight": 5,
    }
    generator.set_ordinary_sampler(ordinary_sampler)
    if device == "cpu":
        autocast = torch.cpu.amp.autocast
    else:
        autocast = torch.cuda.amp.autocast
    with autocast(fp16):
        sequences, tokens = generator.sample_sequences(
            num_samples=1,
            input_prompt=prompt,
            max_length=20,
            caif_period=1,
            caif_tokens_num=100,
            entropy=3.2,
            **kwargs
        )
    return sequences[0]


if __name__ == "__main__":
    main()