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

# Load model and tokenizer
model_id = "PowerInfer/SmallThinker-21BA3B-Instruct"

tokenizer = AutoTokenizer.from_pretrained(model_id)
model = AutoModelForCausalLM.from_pretrained(
    model_id,
    device_map="cpu",  # Force CPU
    torch_dtype=torch.float32
)

# Create generation pipeline
generator = pipeline(
    "text-generation",
    model=model,
    tokenizer=tokenizer,
    device=-1  # CPU
)

# Inference function
def chat(prompt, max_new_tokens=256, temperature=0.7):
    output = generator(
        prompt,
        max_new_tokens=max_new_tokens,
        temperature=temperature,
        do_sample=True,
        pad_token_id=tokenizer.eos_token_id
    )
    return output[0]["generated_text"]

# Launch Gradio app
gr.Interface(
    fn=chat,
    inputs=[
        gr.Textbox(label="Prompt", lines=4, placeholder="Ask anything..."),
        gr.Slider(32, 512, value=256, step=16, label="Max New Tokens"),
        gr.Slider(0.1, 1.5, value=0.7, step=0.1, label="Temperature")
    ],
    outputs=gr.Textbox(label="Response"),
    title="💬 SmallThinker-21BA3B-Instruct",
    description="Run PowerInfer/SmallThinker-21BA3B-Instruct locally on CPU using Hugging Face + Gradio"
).launch()