"""
Gradio + OpenAI MCP Connector — Clean, Fast, Streaming, With File Upload
"""

import os
import shutil
import gradio as gr
from openai import OpenAI

# ---------------------
# CONFIGURATION
# ---------------------
OPENAI_API_KEY = os.getenv("OPENAI_API_KEY")
MCP_SERVER_URL = "https://mcp-1st-birthday-auto-deployer.hf.space/gradio_api/mcp/"
MODEL_FAST = "gpt-5-mini"  # for tool resolution
MODEL_STREAM = "gpt-5.1"  # for final streaming reply

client = OpenAI(api_key=OPENAI_API_KEY)

SYSTEM_PROMPT = """
You are a fast MLOps assistant with access to remote MCP tools.
Use tools only when necessary.
Keep reasoning effort LOW for speed.
After tools run, summarize clearly and concisely.
"""

# ---------------------
# NATIVE MCP CONNECTOR
# ---------------------
TOOLS = [
    {
        "type": "mcp",
        "server_label": "deploy_tools",
        "server_url": MCP_SERVER_URL,
        # transport auto-detected; HF space supports HTTP
    }
]


# ---------------------
# FILE UPLOAD HANDLER
# ---------------------
def handle_upload(file_obj, request: gr.Request):
    if file_obj is None:
        return None

    # Ensure file is in a stable path
    local_path = file_obj.name
    stable_path = os.path.join("/tmp", os.path.basename(local_path))
    try:
        shutil.copy(local_path, stable_path)
        local_path = stable_path
    except Exception:
        pass

    # Build public Gradio URL
    base = str(request.base_url).rstrip("/")
    return f"{base}/gradio_api/file={local_path}"


# ---------------------
# MAIN CHAT HANDLER
# ---------------------
def chat_send_stream(user_msg, history, file_url):
    """
    2-phase pipeline:
        PHASE 1 ➜ Non-streaming tool resolution using gpt-5-mini
        PHASE 2 ➜ Streaming final output using gpt-5
    """

    if history is None:
        history = []

    # Build message history for OpenAI
    messages = [{"role": "system", "content": SYSTEM_PROMPT}]
    for u, a in history:
        messages.append({"role": "user", "content": u})
        if a:
            messages.append({"role": "assistant", "content": a})

    # Inject file context
    if file_url:
        user_msg_full = f"[Uploaded CSV file: {file_url}]\n\n{user_msg}"
    else:
        user_msg_full = user_msg

    messages.append({"role": "user", "content": user_msg_full})

    # -----------------------------
    # PHASE 1 — TOOL RESOLUTION
    # -----------------------------
    tool_phase = client.responses.create(
        model=MODEL_FAST,
        reasoning={"effort": "low"},
        tools=TOOLS,
        instructions=SYSTEM_PROMPT,
        input=messages,
    )

    tool_feedback = []

    # Detect tool calls (if any)
    if tool_phase.output:
        for item in tool_phase.output:
            if item.type == "tool_call":
                tool_feedback.append(f"🛠️ Used tool `{item.name}`.")
            elif item.type == "tool_result":
                tool_feedback.append(f"{item.content}")

        if not tool_feedback:
            tool_feedback.append("No MCP tools needed.")

    else:
        tool_feedback.append("No MCP tools needed.")

    # Append tool results to messages before final generation
    messages.append({"role": "assistant", "content": "\n".join(tool_feedback)})

    # Yield intermediate tool feedback to the UI
    history.append((user_msg, "\n".join(tool_feedback)))
    yield history

    # -----------------------------
    # PHASE 2 — STREAMING FINAL ANSWER
    # -----------------------------
    stream = client.responses.create(
        model=MODEL_STREAM,
        reasoning={"effort": "low"},
        instructions=SYSTEM_PROMPT,
        input=messages,
        stream=True,
    )

    final_text = ""
    for ev in stream:
        if ev.type == "response.output_text.delta":
            final_text += ev.delta
            history[-1] = (user_msg, "\n".join(tool_feedback) + "\n\n" + final_text)
            yield history

        elif ev.type == "response.completed":
            break

    stream.close()


# ---------------------
# GRADIO UI
# ---------------------
with gr.Blocks(title="MCP + GPT-5 — Fast Streaming MLOps Agent") as demo:
    gr.Markdown("""
    # 🚀 AI-Driven MLOps Agent (MCP-Powered)
    - Upload a CSV file  
    - Tools resolve instantly  
    - Final answer streams smoothly  
    """)

    file_state = gr.State()

    uploader = gr.File(label="Upload CSV file", type="filepath", file_count="single")

    uploader.change(handle_upload, inputs=[uploader], outputs=[file_state])

    chatbot = gr.Chatbot(label="Chat")
    msg = gr.Textbox(label="Message")
    send = gr.Button("Send")

    send.click(
        chat_send_stream,
        inputs=[msg, chatbot, file_state],
        outputs=[chatbot],
    ).then(lambda: "", outputs=[msg])

    msg.submit(
        chat_send_stream,
        inputs=[msg, chatbot, file_state],
        outputs=[chatbot],
    ).then(lambda: "", outputs=[msg])


if __name__ == "__main__":
    demo.queue().launch(
        allowed_paths=["/tmp"],
        show_error=True,
        quiet=True,
    )