app.py

import os
import gradio as gr
from huggingface_hub import InferenceClient

# ========= SETTINGS ==========
MODEL_NAME = "mistralai/Mistral-7B-Instruct-v0.3"
BOT_NAME = "XYZ BUSINESS AI"

SYSTEM_PROMPT = f"""You are {BOT_NAME}, a friendly and professional business assistant.
You explain complex ideas clearly, maintain a confident and concise tone,
and help users understand business and finance concepts easily.
"""

# Use HF_TOKEN from secrets (set in Hugging Face Space -> Settings -> Secrets)
HF_TOKEN = os.getenv("HF_TOKEN")

# Initialize client
client = InferenceClient(model=MODEL_NAME, token=HF_TOKEN)

# ========= CHAT LOGIC ==========
def generate_response(user_message, chat_history, max_new_tokens=256, temperature=0.7, top_p=0.9):
    try:
        # Prepare the full message list
        messages = [{"role": "system", "content": SYSTEM_PROMPT}]
        for user, bot in chat_history:
            messages.append({"role": "user", "content": user})
            messages.append({"role": "assistant", "content": bot})
        messages.append({"role": "user", "content": user_message})

        # Stream the response
        response_text = ""
        for chunk in client.chat_completion(
            messages=messages,
            max_tokens=max_new_tokens,
            temperature=temperature,
            top_p=top_p,
            stream=True,
        ):
            delta = chunk.choices[0].delta.get("content", "")
            response_text += delta
            yield response_text

    except Exception as e:
        yield f"⚠️ Error: {str(e)}"


# ========= GRADIO UI ==========
def respond(message, chat_history):
    response_stream = generate_response(message, chat_history)
    response = ""
    for partial in response_stream:
        response = partial
        yield "", chat_history + [(message, response)]


with gr.Blocks(theme=gr.themes.Soft(primary_hue="blue")) as demo:
    gr.Markdown(
        f"""
        <div style="text-align: center;">
            <img src="https://huggingface.co/front/assets/huggingface_logo-noborder.svg" width="80"/>
            <h1 style="margin-bottom:0;">💬 {BOT_NAME}</h1>
            <p style="color: gray;">Your AI business assistant — powered by Mistral-7B-Instruct</p>
        </div>
        """
    )

    chatbot = gr.Chatbot(height=500, label=f"Chat with {BOT_NAME}")
    msg = gr.Textbox(placeholder="Type your message here...", label="Your Message")
    clear = gr.Button("Clear Chat")
    state = gr.State([])

    msg.submit(respond, [msg, state], [msg, chatbot])
    clear.click(lambda: None, None, chatbot, queue=False)

demo.launch()