from datetime import datetime, timedelta
from uuid import uuid4
from fastapi import HTTPException
from app.db.database import db

voice_rooms_collection = db.voice_rooms


def _serialize(doc):
    if not doc:
        return None
    doc["_id"] = str(doc["_id"])
    if "created_at" in doc:
        doc["created_at"] = doc["created_at"].isoformat()
    if "expires_at" in doc and doc["expires_at"]:
        doc["expires_at"] = doc["expires_at"].isoformat()
    return doc


class VoiceRoomService:

    async def list_public_rooms(self):
        rooms = await voice_rooms_collection.find(
            {"public": True}
        ).sort("created_at", -1).to_list(100)

        return [_serialize(r) for r in rooms]

    async def create_room(
        self,
        name: str,
        owner: str,
        public: bool,
        max_users: int = 5,
        ttl_minutes: int | None = None,
    ):
        room_id = str(uuid4())
        invite_code = None if public else uuid4().hex[:6]

        room = {
            "id": room_id,
            "name": name,
            "public": public,
            "invite_code": invite_code,
            "owner": owner,
            "max_users": max_users,
            "created_at": datetime.utcnow(),
            "expires_at": (
                datetime.utcnow() + timedelta(minutes=ttl_minutes)
                if ttl_minutes else None
            ),
        }

        await voice_rooms_collection.insert_one(room)
        return _serialize(room)

    async def get_room(self, room_id: str):
        room = await voice_rooms_collection.find_one({"id": room_id})
        if not room:
            raise HTTPException(404, "Room not found")
        return room

    async def join_by_code(self, code: str):
        room = await voice_rooms_collection.find_one({"invite_code": code})
        if not room:
            raise HTTPException(404, "Invalid invite code")
        return _serialize(room)