// using System;
// using System.Collections.Generic;
// using System.IO;
// using System.Linq;
// using System.Threading;
// using System.Threading.Tasks;
// using ErsatzTV.Core;
// using ErsatzTV.Core.Domain;
// using ErsatzTV.Core.Interfaces.Repositories;
// using LanguageExt;
// using MediatR;
// using static ErsatzTV.Application.MediaSources.Mapper;
// using static LanguageExt.Prelude;
//
// namespace ErsatzTV.Application.MediaSources.Commands
// {
//     public class CreateLocalMediaSourceHandler : IRequestHandler<CreateLocalMediaSource,
//         Either<BaseError, MediaSourceViewModel>>
//     {
//         private readonly IMediaSourceRepository _mediaSourceRepository;
//
//         public CreateLocalMediaSourceHandler(IMediaSourceRepository mediaSourceRepository) =>
//             _mediaSourceRepository = mediaSourceRepository;
//
//         public Task<Either<BaseError, MediaSourceViewModel>> Handle(
//             CreateLocalMediaSource request,
//             CancellationToken cancellationToken) =>
//             Validate(request).MapT(PersistLocalMediaSource).Bind(v => v.ToEitherAsync());
//
//         private Task<MediaSourceViewModel> PersistLocalMediaSource(LocalMediaSource c) =>
//             _mediaSourceRepository.Add(c).Map(ProjectToViewModel);
//
//         private async Task<Validation<BaseError, LocalMediaSource>> Validate(CreateLocalMediaSource request) =>
//             (await ValidateName(request), await ValidateFolder(request))
//             .Apply(
//                 (name, folder) =>
//                     new LocalMediaSource
//                     {
//                         Name = name,
//                         MediaType = request.MediaType,
//                         Folder = folder
//                     });
//
//         private async Task<Validation<BaseError, string>> ValidateName(CreateLocalMediaSource request)
//         {
//             List<string> allNames = await _mediaSourceRepository.GetAll()
//                 .Map(list => list.Map(c => c.Name).ToList());
//
//             Validation<BaseError, string> result1 = request.NotEmpty(c => c.Name)
//                 .Bind(_ => request.NotLongerThan(50)(c => c.Name));
//
//             var result2 = Optional(request.Name)
//                 .Filter(name => !allNames.Contains(name))
//                 .ToValidation<BaseError>("Media source name must be unique");
//
//             return (result1, result2).Apply((_, _) => request.Name);
//         }
//
//         private async Task<Validation<BaseError, string>> ValidateFolder(CreateLocalMediaSource request)
//         {
//             List<string> allFolders = await _mediaSourceRepository.GetAll()
//                 .Map(list => list.OfType<LocalMediaSource>().Map(c => c.Folder).ToList());
//
//
//             return Optional(request.Folder)
//                 .Filter(folder => allFolders.ForAll(f => !AreSubPaths(f, folder)))
//                 .ToValidation<BaseError>("Folder must not belong to another media source");
//         }
//
//         private static bool AreSubPaths(string path1, string path2)
//         {
//             string one = path1 + Path.DirectorySeparatorChar;
//             string two = path2 + Path.DirectorySeparatorChar;
//             return one == two || one.StartsWith(two, StringComparison.OrdinalIgnoreCase) ||
//                    two.StartsWith(one, StringComparison.OrdinalIgnoreCase);
//         }
//     }
// }