"""Shared helpers, serializers and constants for the plex route package."""

import logging

from fastapi import HTTPException
from sqlalchemy import select
from sqlalchemy.orm import Session

from app.models import (
    PlexItem,
    PlexLibrary,
)
from app.plex.lookups import by_rating_key

log = logging.getLogger("siftlode.plex")


def item_or_404(db: Session, rating_key: str) -> PlexItem:
    it = by_rating_key(db, PlexItem, rating_key)
    if it is None:
        raise HTTPException(status_code=404, detail="Unknown Plex item")
    return it


def _norm_lang(lang: str | None) -> str:
    """The overlay has an EN base + an optional HU twin; anything other than `hu` serves EN."""
    return "hu" if lang == "hu" else "en"


def _content_libs(db: Session) -> tuple[list[int], list[int]]:
    """The BROWSABLE content libraries, partitioned into (movie_lib_ids, show_lib_ids) — the single
    source of the browse scope. Excludes HU overlay libraries (`overlay_of` set): those are never
    browsed on their own, they only lend their Hungarian metadata to the EN twin's rows (E5 S5)."""
    libs = (
        db.execute(
            select(PlexLibrary).where(
                PlexLibrary.enabled.is_(True), PlexLibrary.overlay_of.is_(None)
            )
        )
        .scalars()
        .all()
    )
    movie_lib_ids = [lb.id for lb in libs if lb.kind == "movie"]
    show_lib_ids = [lb.id for lb in libs if lb.kind == "show"]
    return movie_lib_ids, show_lib_ids