Musify/backend/Tests/Musify.Application.Tests/Tracks/DeleteTrackCommandHandlerTests.cs

using ErrorOr;
using Musify.Application.Contracts;
using Musify.Application.Tests.TestSupport;
using Musify.Application.Tracks;
using Musify.Domain.ValueObjects;
using NSubstitute;
using Xunit;

namespace Musify.Application.Tests.Tracks
{
    public sealed class DeleteTrackCommandHandlerTests : HandlerTestBase
    {
        private readonly IEventBus eventBus = Substitute.For<IEventBus>();

        private DeleteTrackCommandHandler CreateHandler() => new(Database, eventBus, NoOpLogger<DeleteTrackCommandHandler>());

        [Fact]
        public async Task Handle_Owner_MarksTrackAsRemovingAndPublishesEvent()
        {
            var owner = TestEntities.User();
            var track = TestEntities.LocalTrack(owner);
            await SeedAsync(owner, track);

            var result = await CreateHandler().Handle(new DeleteTrackCommand(owner.Id, track.Id), TestContext.Current.CancellationToken);

            Assert.False(result.IsError);
            var stored = await Database.Tracks.FindAsync([track.Id], TestContext.Current.CancellationToken);
            Assert.NotNull(stored);
            Assert.Equal(LifeCycleStatus.Removing, stored.LifeCycleStatus);
            await eventBus.Received(1).PublishAsync(Arg.Any<Musify.Application.Events.DeleteTrackEvent>(), Arg.Any<CancellationToken>());
        }

        [Fact]
        public async Task Handle_TrackMissing_ReturnsNotFound()
        {
            var result = await CreateHandler().Handle(new DeleteTrackCommand(1, Guid.NewGuid()), TestContext.Current.CancellationToken);

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

        [Fact]
        public async Task Handle_NotOwner_ReturnsUnauthorized()
        {
            var owner = TestEntities.User(1, "owner");
            var stranger = TestEntities.User(2, "stranger");
            var track = TestEntities.LocalTrack(owner);
            await SeedAsync(owner, stranger, track);

            var result = await CreateHandler().Handle(new DeleteTrackCommand(stranger.Id, track.Id), TestContext.Current.CancellationToken);

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

        [Fact]
        public async Task Handle_ExternalTrack_ReturnsUnauthorized()
        {
            var externalTrack = TestEntities.ExternalTrack();
            await SeedAsync(externalTrack);

            var result = await CreateHandler().Handle(new DeleteTrackCommand(1, externalTrack.Id), TestContext.Current.CancellationToken);

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

        [Fact]
        public async Task Handle_AudioStillProcessing_ReturnsConflict()
        {
            var owner = TestEntities.User();
            var track = TestEntities.LocalTrack(owner, audio: TestEntities.PendingAudio());
            await SeedAsync(owner, track);

            var result = await CreateHandler().Handle(new DeleteTrackCommand(owner.Id, track.Id), TestContext.Current.CancellationToken);

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