agent.py

from typing import TypedDict, Annotated
import os
from langgraph.graph.message import add_messages
from langchain_core.messages import AnyMessage, HumanMessage, AIMessage, SystemMessage
from langgraph.prebuilt import ToolNode
from langgraph.graph import START, StateGraph
from langgraph.checkpoint.memory import MemorySaver
from langgraph.prebuilt import tools_condition
from langchain_huggingface import HuggingFaceEndpoint, ChatHuggingFace
from tools import agent_tools
from utils import format_gaia_answer, analyze_question_type, create_execution_plan, log_agent_step

# Initialize LLM (same as unit3)
llm = HuggingFaceEndpoint(
    repo_id="Qwen/Qwen2.5-Coder-32B-Instruct",
    huggingfacehub_api_token=os.environ.get("HUGGINGFACE_API_TOKEN"),
    temperature=0.1,
    max_new_tokens=1024,
)

chat = ChatHuggingFace(llm=llm, verbose=True)
chat_with_tools = chat.bind_tools(agent_tools)

# System prompt for intelligent question answering
SYSTEM_PROMPT = """You are a highly capable AI assistant designed to answer questions accurately and helpfully.

Your approach should include:
- Multi-step reasoning and planning for complex questions
- Intelligent tool usage when needed for web search, file processing, calculations, and analysis
- Precise, factual answers based on reliable information
- Breaking down complex questions into manageable steps

IMPORTANT GUIDELINES:
1. Think step-by-step and use available tools when they can help provide better answers
2. For current information: Search the web for up-to-date facts
3. For files: Process associated files when task_id is provided
4. For visual content: Analyze images carefully when present
5. For calculations: Use computational tools for accuracy
6. Provide concise, direct answers without unnecessary prefixes
7. Focus on accuracy and helpfulness
8. Be factual and avoid speculation

Your goal is to be as helpful and accurate as possible while using the right tools for each task."""

# Generate the AgentState
class AgentState(TypedDict):
    messages: Annotated[list[AnyMessage], add_messages]
    task_id: str
    question_analysis: dict

def assistant(state: AgentState):
    """Main assistant function that processes messages and calls tools."""
    messages = state["messages"]
    
    # Add system prompt if not already present
    if not any(isinstance(msg, SystemMessage) for msg in messages):
        messages = [SystemMessage(content=SYSTEM_PROMPT)] + messages
    
    # Get the response from the LLM
    response = chat_with_tools.invoke(messages)
    
    return {
        "messages": [response],
    }

def create_smart_agent():
    """Create and return the smart agent graph."""
    # Build the graph
    builder = StateGraph(AgentState)
    
    # Define nodes
    builder.add_node("assistant", assistant)
    builder.add_node("tools", ToolNode(agent_tools))
    
    # Define edges
    builder.add_edge(START, "assistant")
    builder.add_conditional_edges(
        "assistant",
        tools_condition,
    )
    builder.add_edge("tools", "assistant")
    
    # Add memory
    memory = MemorySaver()
    agent = builder.compile(checkpointer=memory)
    
    return agent

class SmartAgent:
    """High-level intelligent agent class that wraps the LangGraph agent."""
    
    def __init__(self):
        self.agent = create_smart_agent()
        print("🤖 Smart Agent initialized with LangGraph and tools")
    
    def __call__(self, question: str, task_id: str = None) -> str:
        """Process a question and return the formatted answer."""
        try:
            print(f"\n🎯 Processing question: {question[:100]}...")
            
            # Analyze the question
            analysis = analyze_question_type(question)
            print(f"📊 Question analysis: {analysis}")
            
            # Create execution plan
            plan = create_execution_plan(question, task_id)
            print(f"📋 Execution plan: {plan}")
            
            # Prepare the question with task_id context if available
            enhanced_question = question
            if task_id:
                enhanced_question = f"Task ID: {task_id}\n\nQuestion: {question}\n\nNote: If this question involves files, use the file_download tool with task_id '{task_id}' to access associated files."
            
            # Invoke the agent
            thread_id = f"task-{task_id}" if task_id else "general"
            config = {"configurable": {"thread_id": thread_id}}
            
            initial_state = {
                "messages": [HumanMessage(content=enhanced_question)],
                "task_id": task_id or "",
                "question_analysis": analysis
            }
            
            result = self.agent.invoke(initial_state, config=config)
            
            # Extract the final answer
            if result and 'messages' in result and result['messages']:
                final_message = result['messages'][-1]
                raw_answer = final_message.content
            else:
                raw_answer = "No response generated"
            
            # Format the answer for submission
            formatted_answer = format_gaia_answer(raw_answer)
            
            print(f"✅ Raw answer: {raw_answer}")
            print(f"🎯 Formatted answer: {formatted_answer}")
            
            return formatted_answer
            
        except Exception as e:
            error_msg = f"Error processing question: {str(e)}"
            print(f"❌ {error_msg}")
            return error_msg

smart_agent = SmartAgent()