# modules/nlp/api.py
from fastapi import APIRouter, Depends, HTTPException
from sqlalchemy.orm import Session

from core.database import get_db

from modules.auth.dependencies import get_current_user
from modules.auth.models import User
from modules.nlp.service import process_request, ask_ai
from modules.nlp.schemas import ProcessCommandRequest
from modules.calendar.service import create_calendar_event, get_calendar_events, update_calendar_event, delete_calendar_event
from modules.calendar.schemas import CalendarEventCreate, CalendarEventUpdate

router = APIRouter(prefix="/nlp", tags=["nlp"])

@router.post("/process-command")
def process_command(request_data: ProcessCommandRequest, current_user: User = Depends(get_current_user), db: Session = Depends(get_db)):
    """
    Process the user command, execute the action, and return a user-friendly response.
    """
    user_input = request_data.user_input 
    command_data = process_request(user_input)
    intent = command_data["intent"]
    params = command_data["params"]
    response_text = command_data["response_text"]

    if intent == "error":
        raise HTTPException(status_code=400, detail=response_text)
    
    if intent == "clarification_needed":
        return {"response": response_text}
    
    if intent == "unknown":
        return {"response": response_text}

    try:
        match intent:
            case "ask_ai":
                ai_answer = ask_ai(**params)
                return {"response": ai_answer}
            
            case "get_calendar_events":
                result = get_calendar_events(db, current_user.id, **params)
                return {"response": response_text, "details": result}
            
            case "add_calendar_event":
                event = CalendarEventCreate(**params)
                result = create_calendar_event(db, current_user.id, event)
                return {"response": response_text, "details": result}

            case "update_calendar_event":
                event_id = params.pop('event_id', None)
                if event_id is None:
                    raise HTTPException(status_code=400, detail="Event ID is required for update.")
                event_data = CalendarEventUpdate(**params)
                result = update_calendar_event(db, current_user.id, event_id, event_data=event_data)
                return {"response": response_text, "details": result}
            
            case "delete_calendar_event":
                event_id = params.get('event_id')
                if event_id is None:
                    raise HTTPException(status_code=400, detail="Event ID is required for delete.")
                result = delete_calendar_event(db, current_user.id, event_id)
                return {"response": response_text, "details": {"deleted": True, "event_id": event_id}}
                
            case _: 
                print(f"Warning: Unhandled intent '{intent}' reached api.py match statement.")
                raise HTTPException(status_code=500, detail="An unexpected error occurred processing the command.")

    except HTTPException as http_exc:
        raise http_exc
    except Exception as e:
        print(f"Error executing intent '{intent}': {e}")
        raise HTTPException(status_code=500, detail="Sorry, I encountered an error while trying to perform that action.")