ErsatzTV/ErsatzTV.Infrastructure/Health/Checks/EpisodeMetadataHealthCheck.cs

using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Threading.Tasks;
using ErsatzTV.Core.Domain;
using ErsatzTV.Core.Health;
using ErsatzTV.Core.Health.Checks;
using ErsatzTV.Infrastructure.Data;
using LanguageExt;
using Microsoft.EntityFrameworkCore;
using static LanguageExt.Prelude;

namespace ErsatzTV.Infrastructure.Health.Checks
{
    public class EpisodeMetadataHealthCheck : BaseHealthCheck, IEpisodeMetadataHealthCheck
    {
        private readonly IDbContextFactory<TvContext> _dbContextFactory;

        public EpisodeMetadataHealthCheck(IDbContextFactory<TvContext> dbContextFactory) =>
            _dbContextFactory = dbContextFactory;

        protected override string Title => "Episode Metadata";
        
        public async Task<HealthCheckResult> Check()
        {
            await using TvContext dbContext = _dbContextFactory.CreateDbContext();
            
            List<Episode> episodes = await dbContext.Episodes
                .Filter(e => e.EpisodeMetadata.Count == 0)
                .Include(e => e.MediaVersions)
                .ThenInclude(mv => mv.MediaFiles)
                .ToListAsync();

            if (episodes.Any())
            {
                var paths = episodes.SelectMany(e => e.MediaVersions.Map(mv => mv.MediaFiles))
                    .Flatten()
                    .Bind(f => Optional<string>(Path.GetDirectoryName(f.Path)))
                    .Distinct()
                    .Take(5)
                    .ToList();

                var folders = string.Join(", ", paths);

                return WarningResult($"There are {episodes.Count} episodes with missing metadata, including in the following folders: {folders}");
            }

            return OkResult();
        }
    }
}