Musify/backend/Tests/Musify.Application.Tests/PlayLists/CreatePlayListCommandHandlerTests.cs

using ErrorOr;
using Musify.Application.Contracts;
using Musify.Application.PlayLists;
using Musify.Application.Services;
using Musify.Application.Tests.TestSupport;
using NSubstitute;
using Xunit;

namespace Musify.Application.Tests.PlayLists
{
    public sealed class CreatePlayListCommandHandlerTests : HandlerTestBase
    {
        private readonly IEventBus eventBus = Substitute.For<IEventBus>();
        private readonly IStorageService storageService = Substitute.For<IStorageService>();

        private CreatePlayListCommandHandler CreateHandler() => new(
            eventBus,
            Database,
            new UploadIntentValidator(Database, storageService),
            NoOpLogger<CreatePlayListCommandHandler>(),
            TestConfigurations.Storage(),
            TestConfigurations.PlayList(),
            TestConfigurations.UploadIntent());

        [Fact]
        public async Task Handle_NoPictureIntent_CreatesPlayListWithPresetPictures()
        {
            var user = TestEntities.User();
            await SeedAsync(user);

            var command = new CreatePlayListCommand(user.Id, "My Playlist", "A description", PictureIntentId: null);

            var result = await CreateHandler().Handle(command, TestContext.Current.CancellationToken);

            Assert.False(result.IsError);
            Assert.Equal("My Playlist", result.Value.Name);
            Assert.Equal("PresetSmallPicture.webp", result.Value.SmallImageKeyName);
            await eventBus.DidNotReceive().PublishAsync(Arg.Any<Musify.Application.Events.CreatePlayListResourcesEvent>(), Arg.Any<CancellationToken>());
        }

        [Fact]
        public async Task Handle_WithValidPictureIntent_PublishesResourcesEvent()
        {
            storageService
                .HeadObjectAsync(Arg.Any<string>(), Arg.Any<string>(), Arg.Any<CancellationToken>())
                .Returns(new ObjectMetaData("image/webp", 1024));

            var user = TestEntities.User();
            var intent = TestEntities.UploadIntent(user.Id, Musify.Domain.ValueObjects.UploadIntentPurpose.PlayListPicture, objectName: "cover.webp");
            await SeedAsync(user, intent);

            var command = new CreatePlayListCommand(user.Id, "My Playlist", null, intent.Id);

            var result = await CreateHandler().Handle(command, TestContext.Current.CancellationToken);

            Assert.False(result.IsError);
            var stored = await Database.PlayLists.FindAsync([result.Value.Id], TestContext.Current.CancellationToken);
            Assert.NotNull(stored);
            Assert.Equal("cover.webp", stored.Pictures.OriginalName);
            await eventBus.Received(1).PublishAsync(Arg.Any<Musify.Application.Events.CreatePlayListResourcesEvent>(), Arg.Any<CancellationToken>());
        }

        [Fact]
        public async Task Handle_NoVisibilitySpecified_DefaultsToPrivate()
        {
            var user = TestEntities.User();
            await SeedAsync(user);

            var command = new CreatePlayListCommand(user.Id, "My Playlist", null, PictureIntentId: null);

            var result = await CreateHandler().Handle(command, TestContext.Current.CancellationToken);

            Assert.False(result.IsError);
            Assert.Equal(Musify.Domain.ValueObjects.PlaylistVisibility.Private, result.Value.Visibility);
        }

        [Fact]
        public async Task Handle_PublicVisibility_PersistsIt()
        {
            var user = TestEntities.User();
            await SeedAsync(user);

            var command = new CreatePlayListCommand(user.Id, "My Playlist", null, PictureIntentId: null, Visibility: Musify.Domain.ValueObjects.PlaylistVisibility.Public);

            var result = await CreateHandler().Handle(command, TestContext.Current.CancellationToken);

            Assert.False(result.IsError);
            Assert.Equal(Musify.Domain.ValueObjects.PlaylistVisibility.Public, result.Value.Visibility);
        }

        [Fact]
        public async Task Handle_UserMissing_ReturnsNotFound()
        {
            var command = new CreatePlayListCommand(404, "Orphan Playlist", null, null);

            var result = await CreateHandler().Handle(command, TestContext.Current.CancellationToken);

            Assert.Equal(ErrorType.NotFound, result.FirstError.Type);
        }

        [Fact]
        public async Task Handle_PictureIntentNotFound_ReturnsError()
        {
            var user = TestEntities.User();
            await SeedAsync(user);

            var command = new CreatePlayListCommand(user.Id, "My Playlist", null, Guid.NewGuid());

            var result = await CreateHandler().Handle(command, TestContext.Current.CancellationToken);

            Assert.True(result.IsError);
        }
    }
}