# =======================================================
# Conversational Chatbot with ChatGPT API + Gradio
# Author: Shruti Mandaokar
# =======================================================

import os
import openai
import gradio as gr

# -----------------------------
# 1. Load OpenAI API key from Hugging Face Secrets
# -----------------------------
openai.api_key = os.getenv("OPENAI_API_KEY")
if openai.api_key is None:
    raise ValueError("❌ OPENAI_API_KEY not found. Please add it in Hugging Face Secrets.")

# -----------------------------
# 2. System prompt for chatbot
# -----------------------------
system_prompt = (
    "You are a helpful assistant that corrects grammar and answers questions. "
    "Maintain context of the conversation."
)

# -----------------------------
# 3. Reset conversation history
# -----------------------------
def reset():
    # History format compatible with Gradio Chatbot type='messages'
    return []

# -----------------------------
# 4. Chatbot function
# -----------------------------
def interact_chatbot(user_input: str, history: list, temp: float):
    """
    Maintains context: sends conversation history + new user input to ChatGPT API.
    Returns history in Gradio messages format.
    """
    # Build messages for OpenAI API
    messages = [{"role": "system", "content": system_prompt}]
    for msg in history:
        messages.append({"role": msg["role"], "content": msg["content"]})
    messages.append({"role": "user", "content": user_input})

    # Call OpenAI API
    try:
        response = openai.chat.completions.create(
            model="gpt-3.5-turbo",
            messages=messages,
            temperature=temp,
            max_tokens=200,
        )
        assistant_reply = response.choices[0].message.content
    except Exception as e:
        assistant_reply = f"⚠️ Error: {str(e)}"

    # Update history in Gradio messages format
    history.append({"role": "user", "content": user_input})
    history.append({"role": "assistant", "content": assistant_reply})

    return history

# -----------------------------
# 5. Gradio UI
# -----------------------------
with gr.Blocks(css="""
    .gradio-container {background-color: #f0f4f8;}
    h1 {color: #2b547e; text-align: center;}
    h3 {color: #5a2d82;}
    .footer {text-align: center; color: #666; font-size: 14px; margin-top: 20px;}
""") as demo:

    gr.Markdown("# ✨ Conversational Chatbot with ChatGPT API ✨")
    gr.Markdown("### Made with ❤️ by **Shruti Mandaokar**")

    chatbot = gr.Chatbot(label="💬 Chatbot", type="messages")
    user_input = gr.Textbox(label="Your message", placeholder="Type a sentence...")

    with gr.Column():
        gr.Markdown("### 🎨 Creativity Control")
        temperature_slider = gr.Slider(0.0, 2.0, value=1.0, step=0.1, label="Temperature")

    with gr.Row():
        send_button = gr.Button("🚀 Send")
        reset_button = gr.Button("🔄 Reset Chat")

    send_button.click(
        interact_chatbot,
        inputs=[user_input, chatbot, temperature_slider],
        outputs=[chatbot]
    )

    reset_button.click(reset, outputs=[chatbot])

    gr.Markdown('<div class="footer">🌸 Conversational Chatbot | Shruti Mandaokar 🌸</div>')

# -----------------------------
# 6. Launch the app
# -----------------------------
if __name__ == "__main__":
    on_spaces = os.getenv("SYSTEM") == "spaces"
    demo.launch(share=not on_spaces)