Musify/backend/Tests/Musify.Application.Tests/Mixes/GetMixesByUserIdQueryHandlerTests.cs

using Musify.Application.Mixes;
using Musify.Application.Tests.TestSupport;
using Xunit;

namespace Musify.Application.Tests.Mixes
{
    public sealed class GetMixesByUserIdQueryHandlerTests : HandlerTestBase
    {
        private GetMixesByUserIdQueryHandler CreateHandler() => new(Database);

        [Fact]
        public async Task Handle_ReturnsOnlyThatUsersMixesOrderedByPosition()
        {
            var owner = TestEntities.User(1, "owner");
            var other = TestEntities.User(2, "other");
            var second = TestEntities.Mix(owner.Id, "Second", position: 1);
            var first = TestEntities.Mix(owner.Id, "First", position: 0);
            var theirs = TestEntities.Mix(other.Id, "Theirs");
            await SeedAsync(owner, other, second, first, theirs);

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

            Assert.False(result.IsError);
            Assert.Equal(["First", "Second"], result.Value.Select(mix => mix.Title));
        }

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

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

            Assert.False(result.IsError);
            Assert.Empty(result.Value);
        }
    }
}