import gradio as gr
from rag_engine import RAGEngine

engine = RAGEngine()

# ── Functions ─────────────────────────

def load_pdf(file):
    if not file:
        return "Upload file", gr.update(interactive=False)
    return engine.load_pdf(file.name), gr.update(interactive=True)

def load_url(url):
    if not url:
        return "Enter URL", gr.update(interactive=False)
    return engine.load_url(url), gr.update(interactive=True)

def load_text(text):
    if not text:
        return "Enter text", gr.update(interactive=False)
    return engine.load_text(text), gr.update(interactive=True)

def chat(msg, history):
    if not msg:
        return history, ""
    ans = engine.answer(msg)
    history = history or []
    history.append((msg, ans))
    return history, ""

def reset():
    engine.reset()
    return [], "", "Reset done"

# ── UI ───────────────────────────────

with gr.Blocks(title="RAG Chatbot") as demo:
    gr.Markdown("# 🤖 RAG Chatbot")

    with gr.Row():
        with gr.Column():
            pdf = gr.File()
            btn_pdf = gr.Button("Load PDF")

            url = gr.Textbox()
            btn_url = gr.Button("Load URL")

            text = gr.Textbox(lines=5)
            btn_text = gr.Button("Load Text")

            status = gr.Textbox(value="Load data", interactive=False)

        with gr.Column():
            chatbot = gr.Chatbot()

            msg = gr.Textbox(
                placeholder="Ask something...",
                interactive=False
            )

            send = gr.Button("Send")
            reset_btn = gr.Button("Reset")

    btn_pdf.click(load_pdf, pdf, [status, msg])
    btn_url.click(load_url, url, [status, msg])
    btn_text.click(load_text, text, [status, msg])

    send.click(chat, [msg, chatbot], [chatbot, msg])
    msg.submit(chat, [msg, chatbot], [chatbot, msg])

    reset_btn.click(reset, outputs=[chatbot, msg, status])

# ✅ IMPORTANT (Gradio 6 style)
demo.launch()