import os
import requests
import pandas as pd
import gradio as gr
from langchain_core.messages import HumanMessage
from agent import build_graph

DEFAULT_API_URL = "https://agents-course-unit4-scoring.hf.space"

class BasicAgent:
    def __init__(self):
        self.graph = build_graph()

    def __call__(self, question: str) -> str:
        result = self.graph.invoke({"messages": [HumanMessage(content=question)]})
        return result['messages'][-1].content

def run_and_submit_all(profile: gr.OAuthProfile | None):
    if not profile:
        return "Please Login to Hugging Face with the button.", None
    
    username = profile.username
    agent_code = f"https://huggingface.co/spaces/{os.getenv('SPACE_ID')}/tree/main"
    session = requests.Session()

    try:
        agent = BasicAgent()
    except Exception as e:
        return f"Error initializing agent: {e}", None

    try:
        response = session.get(f"{DEFAULT_API_URL}/questions", timeout=15)
        response.raise_for_status()
        questions = response.json()
        if not questions:
            return "No questions received from server.", None
    except Exception as e:
        return f"Error fetching questions: {e}", None

    results_log = []
    answers_payload = []

    for item in questions:
        task_id = item.get("task_id")
        q = item.get("question")
        if not (task_id and q):
            continue
        try:
            answer = agent(q)
            answers_payload.append({"task_id": task_id, "submitted_answer": answer})
        except Exception as e:
            answer = f"AGENT ERROR: {e}"
        results_log.append({"Task ID": task_id, "Question": q, "Submitted Answer": answer})

    if not answers_payload:
        return "Agent did not produce valid answers.", pd.DataFrame(results_log)

    try:
        res = session.post(
            f"{DEFAULT_API_URL}/submit",
            json={
                "username": username.strip(),
                "agent_code": agent_code,
                "answers": answers_payload
            },
            timeout=60
        )
        res.raise_for_status()
        r = res.json()
        status = (
            f"Submission Successful!\nUser: {r.get('username')}\n"
            f"Score: {r.get('score', 'N/A')}% "
            f"({r.get('correct_count', '?')}/{r.get('total_attempted', '?')})\n"
            f"Message: {r.get('message', 'No message received.')}"
        )
        return status, pd.DataFrame(results_log)

    except requests.exceptions.RequestException as e:
        return f"Submission Failed: {e}", pd.DataFrame(results_log)