from __future__ import annotations

import uuid

from sqlalchemy import select
from sqlalchemy.orm import selectinload

from rehearsalhub.db.models import AudioVersion, Song
from rehearsalhub.repositories.base import BaseRepository


class SongRepository(BaseRepository[Song]):
    model = Song

    async def list_for_band(self, band_id: uuid.UUID) -> list[Song]:
        stmt = (
            select(Song)
            .where(Song.band_id == band_id)
            .options(selectinload(Song.versions))
            .order_by(Song.updated_at.desc())
        )
        result = await self.session.execute(stmt)
        return list(result.scalars().all())

    async def get_with_versions(self, song_id: uuid.UUID) -> Song | None:
        stmt = (
            select(Song)
            .options(selectinload(Song.versions))
            .where(Song.id == song_id)
        )
        result = await self.session.execute(stmt)
        return result.scalar_one_or_none()

    async def get_by_nc_folder_path(self, nc_folder_path: str) -> "Song | None":
        stmt = select(Song).where(Song.nc_folder_path == nc_folder_path)
        result = await self.session.execute(stmt)
        return result.scalar_one_or_none()

    async def get_by_title_and_band(self, band_id: uuid.UUID, title: str) -> "Song | None":
        stmt = select(Song).where(Song.band_id == band_id, Song.title == title)
        result = await self.session.execute(stmt)
        return result.scalar_one_or_none()

    async def next_version_number(self, song_id: uuid.UUID) -> int:
        from sqlalchemy import func

        stmt = select(func.coalesce(func.max(AudioVersion.version_number), 0) + 1).where(
            AudioVersion.song_id == song_id
        )
        result = await self.session.execute(stmt)
        return result.scalar_one()