app.py

import os
import re
import gradio as gr
import requests
import inspect
import pandas as pd
from transformers import AutoModelForCausalLM, AutoTokenizer, pipeline
import torch
from langchain_community.llms import HuggingFacePipeline
from tools import tools
from langchain_core.messages import HumanMessage, AIMessage
from langgraph.prebuilt import ToolNode, create_react_agent
from langgraph.graph import StateGraph, END
from langchain.agents import tool
from langchain_core.runnables import Runnable
from langchain_core.tools import Tool
from langchain_community.chat_models import ChatHuggingFace


# (Keep Constants as is)
# --- Constants ---
DEFAULT_API_URL = "https://agents-course-unit4-scoring.hf.space"

# --- Basic Agent Definition ---
# ----- THIS IS WERE YOU CAN BUILD WHAT YOU WANT ------
class BasicAgent:
    def __init__(self):
        print("BasicAgent initialized.")
    def __call__(self, question: str) -> str:
        print(f"Agent received question (first 50 chars): {question[:50]}...")
        fixed_answer = "This is a default answer."
        print(f"Agent returning fixed answer: {fixed_answer}")
        return fixed_answer

class ZephyrAPI:
    def __init__(self, tools=None):
        self.api_url = "https://api-inference.huggingface.co/models/HuggingFaceH4/zephyr-7b-beta"
        self.headers = {
            "Authorization": f"Bearer {os.getenv('HF_TOKEN')}"
        }
        self.tool_descriptions = self.format_tools(tools or [])
        print(f"ZephyrAPI initialized using Inference API. with tools {self.tool_descriptions}")

    def format_tools(self, tools):
        return "\n".join([f"- {tool.name}: {tool.description}" for tool in tools])

    def __call__(self, question: str, scratchpad: str = "") -> str:
        prompt = f"""<|system|>
                You are a helpful AI assistant that can answer questions using tools if needed.

                Use the following reasoning format to answer questions:

                Thought: [your reasoning]
                Action: [tool name]
                Action Input: [JSON-encoded input arguments for the tool]
                
                After you see an Observation from a tool, continue reasoning:
                
                Observation: [tool output]
                Thought: [continue reasoning]
                FINAL ANSWER: [your final answer]

                Answer rules:
                - YOUR FINAL ANSWER should be a number OR as few words as possible OR a comma separated list of numbers and/or strings. 
                - If you are asked for a number, don't use comma to write your number neither use units such as $ or percent sign unless specified otherwise. 
                - If you are asked for a string, don't use articles, neither abbreviations (e.g. for cities), and write the digits in plain text unless specified otherwise. 
                - If you are asked for a comma separated list, apply the above rules depending of whether the element to be put in the list is a number or a string.
                
                You have access to the following tools:
                {self.tool_descriptions}
                
                <|user|>
                {question}
                
                <|assistant|>
                {scratchpad}"""
        
        payload = {
            "inputs": prompt,
            "parameters": {
                "max_new_tokens": 512,
                "temperature": 0.7,
                "top_p": 0.9,
            }
        }

        try:
            response = requests.post(self.api_url, headers=self.headers, json=payload, timeout=60)
            response.raise_for_status()
            result = response.json()
            return result[0]["generated_text"].split("<|assistant|>")[-1].strip()
        except Exception as e:
            print(f"Error: {e}")
            return "⚠️ Model could not respond. Check API access or token."


class LangGraphAgent:
    def __init__(self, tools=None):
        self.tools = {tool.name: tool for tool in tools} if tools else {}
        self.model = ZephyrAPI(tools=tools)

        builder = StateGraph(dict)

        def call_model(state):
            messages = state.get("messages", [])
            user_msg = next((m for m in messages if isinstance(m, HumanMessage)), None)
            if not user_msg:
                return {"messages": messages + [AIMessage(content="❌ No user input found.")]}

            content = user_msg.content.strip()
            raw_response = self.model(content)

            # Detect tool usage
            match = re.search(r"Action:\s*(\w+)\s*Action Input:\s*\"(.+?)\"", raw_response, re.DOTALL)
            if match:
                tool_name, tool_input = match.groups()
                tool_fn = self.tools.get(tool_name)
                if tool_fn:
                    try:
                        tool_output = tool_fn.invoke(tool_input)
                        scratchpad = f"{raw_response}\nObservation: {tool_output}"
                        follow_up = self.model(content, scratchpad)
                        return {"messages": messages + [
                            AIMessage(content=raw_response),
                            AIMessage(content=f"Observation: {tool_output}"),
                            AIMessage(content=follow_up),
                        ]}
                    except Exception as e:
                        return {"messages": messages + [AIMessage(content=f"⚠️ Tool error: {e}")]}

                else:
                    return {"messages": messages + [AIMessage(content=f"⚠️ Unknown tool: {tool_name}")]}

            return {"messages": messages + [AIMessage(content=raw_response)]}

        builder.add_node("chat", call_model)
        builder.set_entry_point("chat")
        builder.add_edge("chat", END)

        self.graph = builder.compile()

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

        messages = result.get("messages", [])
        for msg in reversed(messages):
            if isinstance(msg, AIMessage):
                return msg.content

        return "❌ No response generated."

def run_and_submit_all( profile: gr.OAuthProfile | None):
    """
    Fetches all questions, runs the BasicAgent on them, submits all answers,
    and displays the results.
    """
    # --- Determine HF Space Runtime URL and Repo URL ---
    space_id = os.getenv("SPACE_ID") # Get the SPACE_ID for sending link to the code

    if profile:
        username= f"{profile.username}"
        print(f"User logged in: {username}")
    else:
        print("User not logged in.")
        return "Please Login to Hugging Face with the button.", None

    api_url = DEFAULT_API_URL
    questions_url = f"{api_url}/questions"
    submit_url = f"{api_url}/submit"

    # 1. Instantiate Agent ( modify this part to create your agent)
    try:
        agent = BasicAgent()
    except Exception as e:
        print(f"Error instantiating agent: {e}")
        return f"Error initializing agent: {e}", None
    # In the case of an app running as a hugging Face space, this link points toward your codebase ( usefull for others so please keep it public)
    agent_code = f"https://huggingface.co/spaces/{space_id}/tree/main"
    print(agent_code)

    # 2. Fetch Questions
    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:
             print("Fetched questions list is empty.")
             return "Fetched questions list is empty or invalid format.", None
        print(f"Fetched {len(questions_data)} questions.")
    except requests.exceptions.RequestException as e:
        print(f"Error fetching questions: {e}")
        return f"Error fetching questions: {e}", None
    except requests.exceptions.JSONDecodeError as e:
         print(f"Error decoding JSON response from questions endpoint: {e}")
         print(f"Response text: {response.text[:500]}")
         return f"Error decoding server response for questions: {e}", None
    except Exception as e:
        print(f"An unexpected error occurred fetching questions: {e}")
        return f"An unexpected error occurred fetching questions: {e}", None

    # 3. Run your Agent
    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:
            print(f"Skipping item with missing task_id or question: {item}")
            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:
             print(f"Error running agent on task {task_id}: {e}")
             results_log.append({"Task ID": task_id, "Question": question_text, "Submitted Answer": f"AGENT ERROR: {e}"})

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

    # 4. Prepare Submission 
    submission_data = {"username": username.strip(), "agent_code": agent_code, "answers": answers_payload}
    status_update = f"Agent finished. Submitting {len(answers_payload)} answers for user '{username}'..."
    print(status_update)

    # 5. Submit
    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.')}"
        )
        print("Submission successful.")
        results_df = pd.DataFrame(results_log)
        return final_status, results_df
    except requests.exceptions.HTTPError as e:
        error_detail = f"Server responded with status {e.response.status_code}."
        try:
            error_json = e.response.json()
            error_detail += f" Detail: {error_json.get('detail', e.response.text)}"
        except requests.exceptions.JSONDecodeError:
            error_detail += f" Response: {e.response.text[:500]}"
        status_message = f"Submission Failed: {error_detail}"
        print(status_message)
        results_df = pd.DataFrame(results_log)
        return status_message, results_df
    except requests.exceptions.Timeout:
        status_message = "Submission Failed: The request timed out."
        print(status_message)
        results_df = pd.DataFrame(results_log)
        return status_message, results_df
    except requests.exceptions.RequestException as e:
        status_message = f"Submission Failed: Network error - {e}"
        print(status_message)
        results_df = pd.DataFrame(results_log)
        return status_message, results_df
    except Exception as e:
        status_message = f"An unexpected error occurred during submission: {e}"
        print(status_message)
        results_df = pd.DataFrame(results_log)
        return status_message, results_df


# --- Build Gradio Interface using Blocks ---
with gr.Blocks() as demo:
    gr.Markdown("# Basic Agent Evaluation Runner")
    gr.Markdown(
        """
        **Instructions:**

        1.  Please clone this space, then modify the code to define your agent's logic, the tools, the necessary packages, etc ...
        2.  Log in to your Hugging Face account using the button below. This uses your HF username for submission.
        3.  Click 'Run Evaluation & Submit All Answers' to fetch questions, run your agent, submit answers, and see the score.

        ---
        **Disclaimers:**
        Once clicking on the "submit button, it can take quite some time ( this is the time for the agent to go through all the questions).
        This space provides a basic setup and is intentionally sub-optimal to encourage you to develop your own, more robust solution. For instance for the delay process of the submit button, a solution could be to cache the answers and submit in a seperate action or even to answer the questions in async.
        """
    )

    gr.LoginButton()

    # run_button = gr.Button("Run Evaluation & Submit All Answers")

    # status_output = gr.Textbox(label="Run Status / Submission Result", lines=5, interactive=False)
    # # Removed max_rows=10 from DataFrame constructor
    # results_table = gr.DataFrame(label="Questions and Agent Answers", wrap=True)

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

    # ✅ New test section
    gr.Markdown("## 🧪 Quick Agent Test")
    question_input = gr.Textbox(label="Enter a question to test your agent")
    answer_output = gr.Textbox(label="Agent's answer")

    test_button = gr.Button("Test Agent")

    def test_agent_response(question: str) -> str:
        # agent = BasicAgent()
        agent = LangGraphAgent(tools=tools)
        print(agent("What's the capital of France?"))
        return agent(question)

    test_button.click(fn=test_agent_response, inputs=question_input, outputs=answer_output)

    # ✅ Keep submission button
    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,
        outputs=[status_output, results_table]
    )

    

if __name__ == "__main__":
    print("\n" + "-"*30 + " App Starting " + "-"*30)
    # Check for SPACE_HOST and SPACE_ID at startup for information
    space_host_startup = os.getenv("SPACE_HOST")
    space_id_startup = os.getenv("SPACE_ID") # Get SPACE_ID at startup

    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 environment variable not found (running locally?).")

    if space_id_startup: # Print repo URLs if SPACE_ID is found
        print(f"✅ SPACE_ID found: {space_id_startup}")
        print(f"   Repo URL: https://huggingface.co/spaces/{space_id_startup}")
        print(f"   Repo Tree URL: https://huggingface.co/spaces/{space_id_startup}/tree/main")
    else:
        print("ℹ️  SPACE_ID environment variable not found (running locally?). 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)