using ErsatzTV.Core.Domain;
using Microsoft.EntityFrameworkCore;

namespace ErsatzTV.Application.MediaCollections;

internal static class RerunCollectionQueryExtensions
{
    /// <summary>
    ///     The single source of truth for the navigation graph a <see cref="RerunCollection" /> needs before it
    ///     can be projected via <see cref="Mapper.ProjectToViewModel(RerunCollection)" />. Both the paged-list
    ///     and by-id handlers reload through this chain so the two cannot drift apart again (see #671 — the list
    ///     handler had no includes at all, so every row projected a null selection, while the by-id handler
    ///     covered only Movie/Season/Show/Artist and so returned a null selection for Song/OtherVideo/Image and
    ///     a 500 for Episode/MusicVideo).
    ///     Because the id and the display name are both read off these navigations, an un-included type does not
    ///     merely lose its label — it loses the selected id too, which is what silently cleared a stored
    ///     selection in the editor.
    ///     Deliberately narrower than the analogous playlist-item chain in <c>GetPlaylistItemsHandler</c>: the
    ///     rerun projection reads only each selection's id and title, never its artwork, so the
    ///     <c>.ThenInclude(… =&gt; …Artwork)</c> legs are omitted rather than paid for on every page.
    /// </summary>
    public static IQueryable<RerunCollection> IncludeSelectionDetails(this IQueryable<RerunCollection> query) =>
        query
            .Include(c => c.Collection)
            .Include(c => c.MultiCollection)
            .Include(c => c.SmartCollection)
            .Include(c => c.MediaItem)
            .ThenInclude(i => (i as Movie).MovieMetadata)
            .Include(c => c.MediaItem)
            .ThenInclude(i => (i as Show).ShowMetadata)
            // No (i as Season).SeasonMetadata leg on purpose: ProjectToViewModel(Season) builds its name
            // from Show.ShowMetadata and the scalar SeasonNumber, and never reads SeasonMetadata.
            .Include(c => c.MediaItem)
            .ThenInclude(i => (i as Season).Show)
            .ThenInclude(s => s.ShowMetadata)
            .Include(c => c.MediaItem)
            .ThenInclude(i => (i as Artist).ArtistMetadata)
            .Include(c => c.MediaItem)
            .ThenInclude(i => (i as Episode).EpisodeMetadata)
            .Include(c => c.MediaItem)
            .ThenInclude(i => (i as Episode).Season)
            .ThenInclude(s => s.Show)
            .ThenInclude(s => s.ShowMetadata)
            .Include(c => c.MediaItem)
            .ThenInclude(i => (i as MusicVideo).MusicVideoMetadata)
            .Include(c => c.MediaItem)
            .ThenInclude(i => (i as MusicVideo).Artist)
            .ThenInclude(a => a.ArtistMetadata)
            .Include(c => c.MediaItem)
            .ThenInclude(i => (i as OtherVideo).OtherVideoMetadata)
            .Include(c => c.MediaItem)
            .ThenInclude(i => (i as Song).SongMetadata)
            .Include(c => c.MediaItem)
            .ThenInclude(i => (i as Image).ImageMetadata)
            .Include(c => c.MediaItem)
            .ThenInclude(i => (i as RemoteStream).RemoteStreamMetadata);
}