import logging
from fastapi import FastAPI, HTTPException
from fastapi.responses import JSONResponse

from langgraph.errors import GraphRecursionError
from langchain_groq import ChatGroq
from apps.models import QueryInput
from apps.agent.graph import Agent
from apps.agent.constant import GROQ_API_KEY, MODEL_GROQ, CONFIG

logging.basicConfig(level=logging.INFO)
logger = logging.getLogger(__name__)

llm = ChatGroq(model=MODEL_GROQ, api_key=GROQ_API_KEY, temperature=0.1)
agent = Agent(llm=llm)

app = FastAPI(
    title="Agent API",
    description="API to interact with the RAG agent.",
    version="0.1.0",
    docs_url="/docs",
    redoc_url="/redoc",
    openapi_url="/openapi.json",
)

@app.get("/", summary="API Health Check", tags=["Health"])
async def health_check():
    """Endpoint for checking the API status."""
    return {"status": "API is running"}


@app.post("/query-agent", summary="Query the RAG Agent", tags=["Agent"])
async def query_rag_agent(query: QueryInput):
    """ """
    try:
        output = agent.graph.invoke({"messages": ("user", query.query)}, CONFIG)
    
        response = output["messages"][-1].content
        
        logger.info(f"Processed query successfully: {query.query}")

        return JSONResponse(
            content={"response": response},
            media_type="application/json",
            status_code=200
        )

    except GraphRecursionError:
        logger.error("Graph recursion limit reached; query processing failed.")
        raise HTTPException(
            status_code=500,
            detail="Recursion limit reached. Could not generate response despite 25 attempts."
        )