Musify/backend/Tests/Musify.Application.Tests/Likes/ToggleTrackLikeCommandHandlerTests.cs

using ErrorOr;
using Microsoft.EntityFrameworkCore;
using Musify.Application.Likes;
using Musify.Application.Tests.TestSupport;
using Xunit;

namespace Musify.Application.Tests.Likes
{
    public sealed class ToggleTrackLikeCommandHandlerTests : HandlerTestBase
    {
        private ToggleTrackLikeCommandHandler CreateHandler() =>
            new(Database, NoOpLogger<ToggleTrackLikeCommandHandler>());

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

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

            Assert.False(result.IsError);
            Assert.True(result.Value);
            Assert.Single(await Database.TrackLikes.ToListAsync(TestContext.Current.CancellationToken));
        }

        [Fact]
        public async Task Handle_TrackAlreadyLiked_UnlikesIt()
        {
            var owner = TestEntities.User();
            var track = TestEntities.Track(owner);
            await SeedAsync(owner, track, new Musify.Domain.Entities.TrackLike { UserId = owner.Id, TrackId = track.Id });

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

            Assert.False(result.IsError);
            Assert.False(result.Value);
            Assert.Empty(await Database.TrackLikes.ToListAsync(TestContext.Current.CancellationToken));
        }

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

            var result = await CreateHandler().Handle(
                new ToggleTrackLikeCommand(owner.Id, Guid.NewGuid()), TestContext.Current.CancellationToken);

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