"""Assembles Genre API responses from repository data.

Genres have no detail page of their own -- they only ever appear embedded
in movie/series responses (see app/services/common.py) and as entries in
this directory listing, which exists so a client can resolve the Aurora
genre ids that GET /movies and GET /series accept as a filter without
having to have already seen a title in that genre first."""

from __future__ import annotations

from sqlalchemy.ext.asyncio import AsyncSession

from app.core.ids import aurora_id
from app.repositories import genre_repository
from app.schemas.common import GenreListOut, GenreOut


async def list_genres(session: AsyncSession, *, page: int, page_size: int) -> GenreListOut:
    genres, total = await genre_repository.list_genres(
        session, limit=page_size, offset=(page - 1) * page_size
    )
    results = [GenreOut(id=aurora_id("genre", str(g.id)), name=g.name) for g in genres]
    total_pages = (total + page_size - 1) // page_size if total else 0

    return GenreListOut(
        page=page, page_size=page_size, total_results=total, total_pages=total_pages, results=results
    )