import gradio as gr
from huggingface_hub import InferenceClient

def respond(message, history, system_message, max_tokens, temperature, top_p, hf_token):
    """
    Streaming responses from Hugging Face Inference API
    """
    if not hf_token:
        yield "Error: Please provide your Hugging Face token."
        return

    client = InferenceClient(token=hf_token, model="openai/gpt-oss-20b")

    messages = [{"role": "system", "content": system_message}]
    messages.extend(history)
    messages.append({"role": "user", "content": message})

    response = ""
    for message_chunk in client.chat_completion(
        messages,
        max_tokens=max_tokens,
        stream=True,
        temperature=temperature,
        top_p=top_p,
    ):
        choices = message_chunk.choices
        token = ""
        if len(choices) and choices[0].delta.content:
            token = choices[0].delta.content
        response += token
        yield response

# --- Gradio UI ---
with gr.Blocks() as demo:
    with gr.Sidebar():
        gr.Markdown("## Chatbot Settings")
        hf_token = gr.Textbox(
            placeholder="Paste your Hugging Face token here",
            label="Hugging Face Token",
            type="password"
        )
        system_message = gr.Textbox(
            value="You are a friendly Chatbot.",
            label="System message"
        )
        max_tokens = gr.Slider(
            minimum=1, maximum=2048, value=512, step=1, label="Max new tokens"
        )
        temperature = gr.Slider(
            minimum=0.1, maximum=4.0, value=0.7, step=0.1, label="Temperature"
        )
        top_p = gr.Slider(
            minimum=0.1, maximum=1.0, value=0.95, step=0.05,
            label="Top-p (nucleus sampling)"
        )

    chatbot = gr.Chatbot()
    state = gr.State([])  # conversation history
    msg = gr.Textbox(label="Your message")

    msg.submit(
        respond,
        inputs=[msg, state, system_message, max_tokens, temperature, top_p, hf_token],
        outputs=[chatbot],
        show_progress=True
    )

if __name__ == "__main__":
    demo.launch()