app/routers/chat_session.py

# app/routers/chat_session.py
from datetime import datetime
from bson import ObjectId
from fastapi import APIRouter, Depends, HTTPException
from pydantic import BaseModel

from app.database.database_query import DatabaseQuery
from app.middleware.auth import get_current_user

router = APIRouter()
query = DatabaseQuery()

class ChatSessionTitleUpdate(BaseModel):
    title: str

@router.post('/chat-sessions', status_code=201)
async def create_chat_session(username: str = Depends(get_current_user)):
    try:
        session_id = str(ObjectId())

        chat_session = {
            "user_id": username,
            "session_id": session_id,
            "created_at": datetime.utcnow(),
            "last_accessed": datetime.utcnow(),
            "title": "New Chat"
        }
        query.create_chat_session(chat_session)
        return {"message": "Chat session created", "session_id": session_id}
    except Exception as e:
        raise HTTPException(status_code=500, detail=str(e))

@router.get('/chat-sessions')
async def get_user_chat_sessions(username: str = Depends(get_current_user)):
    try:
        sessions = query.get_user_chat_sessions(username)
        return sessions
    except Exception as e:
        raise HTTPException(status_code=500, detail=str(e))
    
@router.delete('/chat-sessions/{session_id}')
async def delete_chat_session(session_id: str, username: str = Depends(get_current_user)):
    try:
        result = query.delete_chat_session(session_id, username)

        if result["session_deleted"]:
            return {
                "message": "Chat session and associated chats deleted successfully",
                "chats_deleted": result["chats_deleted"]
            }
        raise HTTPException(status_code=404, detail="Chat session not found or unauthorized")
    except Exception as e:
        raise HTTPException(status_code=500, detail=str(e))
    
@router.put('/chat-sessions/{session_id}/title')
async def update_chat_title(
    session_id: str, 
    title_data: ChatSessionTitleUpdate, 
    username: str = Depends(get_current_user)
):
    try:
        new_title = title_data.title

        if not query.verify_session(session_id, username):
            raise HTTPException(status_code=404, detail="Chat session not found or unauthorized")

        if query.update_chat_session_title(session_id, new_title):
            return {
                'message': 'Chat session title updated successfully',
                'session_id': session_id,
                'new_title': new_title
            }

        raise HTTPException(status_code=500, detail="Failed to update chat session title")
    except Exception as e:
        raise HTTPException(status_code=500, detail=str(e))

@router.delete('/chat-sessions/all')
async def delete_all_sessions_and_chats(username: str = Depends(get_current_user)):
    try:
        result = query.delete_all_user_sessions_and_chats(username)

        return {
            "message": "Successfully deleted all chat sessions and chats",
            "deleted_chats": result["deleted_chats"],
            "deleted_sessions": result["deleted_sessions"]
        }
    except Exception as e:
        raise HTTPException(status_code=500, detail=str(e))

@router.get('/chats/session/{session_id}')
async def get_session_chats(session_id: str, username: str = Depends(get_current_user)):
    try:
        chats = query.get_session_chats(session_id, username)
        return chats
    except Exception as e:
        raise HTTPException(status_code=500, detail=str(e))