import os
import gradio as gr
import requests
import pandas as pd

from agent import build_graph
from langchain_core.messages import HumanMessage

import re

def extract_answer(text: str) -> str:
    """
    Clean and extract the final answer from agent output.
    Removes prefixes like 'FINAL ANSWER:', trims punctuation,
    and normalizes separators.
    """
    # 提取 final answer 后内容
    match = re.search(r"(final\s*answer|answer\s*is)[:：]?\s*(.+)", text, re.IGNORECASE)
    answer = match.group(2) if match else text

    # 清理格式
    answer = answer.strip().lstrip(":").strip()     # ✅ 去掉前导冒号和空格
    answer = answer.rstrip('.').strip()

    # 多项格式化
    if ',' in answer:
        answer = ",".join(part.strip() for part in answer.split(','))
    if ';' in answer:
        answer = "; ".join(part.strip() for part in answer.split(';'))

    return answer



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

# --- Basic Agent Definition ---
class BasicAgent:
    def __init__(self, provider: str = "openai"):
        print(f"Initializing LangGraph Agent with provider: {provider}")
        self.graph = build_graph(provider=provider)

    def __call__(self, question: str) -> str:
        print(f"Running LangGraph Agent on question: {question[:50]}...")
        try:
            messages = [HumanMessage(content=question)]
            result = self.graph.invoke({"messages": messages})
            outputs = result["messages"]
            for m in reversed(outputs):
                if m.type == "ai":
                    raw_answer = m.content
                    clean = extract_answer(raw_answer)
                    print(f"Extracted clean answer: {clean}")
                    return clean
            return ""
        except Exception as e:
            print(f"LangGraph Agent error: {e}")
            return f"Error: {str(e)}"


def run_and_submit_all(username: str):
    if not username:
        return "❌ Please enter your Hugging Face username.", None

    space_id = os.getenv("SPACE_ID")
    api_url = DEFAULT_API_URL
    questions_url = f"{api_url}/questions"
    submit_url = f"{api_url}/submit"

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

    agent_code = f"https://huggingface.co/spaces/{space_id}/tree/main" if space_id else "N/A"

    print(f"Fetching questions from: {questions_url}")
    try:
        response = requests.get(questions_url, timeout=15)
        response.raise_for_status()
        questions_data = response.json()
        if not questions_data:
            return "Fetched questions list is empty or invalid format.", None
        print(f"Fetched {len(questions_data)} questions.")
    except requests.exceptions.RequestException as e:
        return f"Error fetching questions: {e}", None

    results_log = []
    answers_payload = []
    print(f"Running agent on {len(questions_data)} questions...")
    for item in questions_data:
        task_id = item.get("task_id")
        question_text = item.get("question")
        if not task_id or question_text is None:
            continue
        try:
            submitted_answer = agent(question_text)
            answers_payload.append({"task_id": task_id, "submitted_answer": submitted_answer})
            results_log.append({"Task ID": task_id, "Question": question_text, "Submitted Answer": submitted_answer})
        except Exception as e:
            results_log.append({"Task ID": task_id, "Question": question_text, "Submitted Answer": f"AGENT ERROR: {e}"})

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

    submission_data = {
        "username": username.strip(),
        "agent_code": agent_code,
        "answers": answers_payload
    }

    print(f"Submitting {len(answers_payload)} answers to: {submit_url}")
    try:
        response = requests.post(submit_url, json=submission_data, timeout=60)
        response.raise_for_status()
        result_data = response.json()
        final_status = (
            f"✅ Submission Successful!\n"
            f"User: {result_data.get('username')}\n"
            f"Overall Score: {result_data.get('score', 'N/A')}% "
            f"({result_data.get('correct_count', '?')}/{result_data.get('total_attempted', '?')} correct)\n"
            f"Message: {result_data.get('message', 'No message received.')}"
        )
        results_df = pd.DataFrame(results_log)
        return final_status, results_df
    except Exception as e:
        return f"❌ Submission Failed: {e}", pd.DataFrame(results_log)

# --- Gradio Interface ---
with gr.Blocks() as demo:
    gr.Markdown("# Basic Agent Evaluation Runner")
    gr.Markdown(
        """
        **Instructions:**
        1. Please enter your Hugging Face username below manually.
        2. Click 'Run Evaluation & Submit All Answers' to fetch questions, run your agent, submit answers, and see your score.
        ---
        """
    )

    username_box = gr.Textbox(label="Your Hugging Face Username (for submission)", placeholder="e.g. johndoe")

    run_button = gr.Button("Run Evaluation & Submit All Answers")
    status_output = gr.Textbox(label="Run Status / Submission Result", lines=5, interactive=False)
    results_table = gr.DataFrame(label="Questions and Agent Answers", wrap=True)

    run_button.click(
        fn=run_and_submit_all,
        inputs=[username_box],
        outputs=[status_output, results_table]
    )

if __name__ == "__main__":
    print("\n" + "-"*30 + " App Starting " + "-"*30)
    space_host_startup = os.getenv("SPACE_HOST")
    space_id_startup = os.getenv("SPACE_ID")

    if space_host_startup:
        print(f"✅ SPACE_HOST found: {space_host_startup}")
        print(f"   Runtime URL should be: https://{space_host_startup}.hf.space")
    else:
        print("ℹ️  SPACE_HOST not found (running locally?).")

    if space_id_startup:
        print(f"✅ SPACE_ID found: {space_id_startup}")
        print(f"   Repo URL: https://huggingface.co/spaces/{space_id_startup}")
    else:
        print("ℹ️  SPACE_ID not found. Repo URL cannot be determined.")

    print("-"*(60 + len(" App Starting ")) + "\n")
    print("Launching Gradio Interface for Basic Agent Evaluation...")
    demo.launch(debug=True, share=False)