import os
import math
import transformers
from transformers import AutoModelForCausalLM, AutoTokenizer
import torch
import gradio as gr
import sentencepiece
from tokenization_xgen import XgenTokenizer

title = "Welcome to 🙋🏻‍♂️Tonic's😈Xgen-8K Chat!"
description = "Interestingly there simply wasnt a public demo for Xgen, So I made one. You can use [Salesforce/xgen-7b-8k-inst](https://huggingface.co/Salesforce/xgen-7b-8k-inst) via API using Gradio by scrolling down and clicking Use 'Via API' or privately by [cloning this space on huggingface](https://huggingface.co/spaces/Tonic1/Xgen?duplicate=true) . [Join my active builders' server on discord](https://discord.gg/VqTxc76K3u). Let's build together!."

os.environ['PYTORCH_CUDA_ALLOC_CONF'] = 'max_split_size_mb:50'
device = torch.device("cuda:0" if torch.cuda.is_available() else "cpu")
model_name = "Salesforce/xgen-7b-8k-base"
tokenizer = XgenTokenizer.from_pretrained("./")
model = AutoModelForCausalLM.from_pretrained(model_name,  torch_dtype=torch.bfloat16, device_map="auto")

class XgenChatBot:
    def __init__(self, model, tokenizer, system_message="You are Xgen, an AI language model created by Tonic-AI. You are a cautious assistant. You carefully follow instructions. You are helpful and harmless and you follow ethical guidelines and promote positive behavior."):
        self.model = model
        self.tokenizer = tokenizer
        self.system_message = system_message

    def set_system_message(self, new_system_message):
        self.system_message = new_system_message

    def format_prompt(self, user_message):
        prompt = f"<|im_start|>assistant\n{self.system_message}<|im_end|>\n<|im_start|>\nuser\n{user_message}<|im_end|>\nassistant\n"
        return prompt

    def predict(self, user_message, temperature=0.4, max_new_tokens=70, top_p=0.99, repetition_penalty=1.9):
        prompt = self.format_prompt(user_message)
        inputs = self.tokenizer(prompt, return_tensors='pt', add_special_tokens=False)
        input_ids = inputs["input_ids"].to(self.model.device)

        output_ids = self.model.generate(
            input_ids,
            max_length=input_ids.shape[1] + max_new_tokens,
            temperature=temperature,
            top_p=top_p,
            repetition_penalty=repetition_penalty,
            do_sample=True
        )

        response = self.tokenizer.decode(output_ids[0], skip_special_tokens=True)
        return response

def gradio_predict(user_message, system_message, max_new_tokens, temperature, top_p, repetition_penalty):
    Xgen_bot.set_system_message(system_message)
    response = Xgen_bot.predict(user_message, temperature, max_new_tokens, top_p, repetition_penalty)
    return response
    
Xgen_bot = XgenChatBot(model, tokenizer)

iface = gr.Interface(
    fn=gradio_predict,
    title=title,
    description=description,
    inputs=[
        gr.Textbox(label="Your Message", type="text", lines=3),
        gr.Textbox(label="Introduce a Character Here or Set a Scene (system prompt)", type="text", lines=2),
        gr.Slider(label="Max new tokens", value=550, minimum=360, maximum=600, step=1),
        gr.Slider(label="Temperature", value=0.1, minimum=0.05, maximum=1.0, step=0.05),
        gr.Slider(label="Top-p (nucleus sampling)", value=0.90, minimum=0.01, maximum=0.99, step=0.05),
        gr.Slider(label="Repetition penalty", value=1.9, minimum=1.0, maximum=2.0, step=0.05)
    ],
    outputs="text",
    theme="ParityError/Anime"
)

iface.queue(max_size=5).launch()