Musify/backend/Tests/Musify.Api.Tests/Endpoints/GenreEndpointsTests.cs

using System.Net;
using System.Net.Http.Json;
using System.Text.Json;
using System.Text.Json.Serialization;
using Microsoft.Extensions.DependencyInjection;
using Musify.Api.Tests.TestSupport;
using Musify.Application.Genres.Responses;
using Musify.Application.Shared;
using Musify.Application.Tracks.Responses;
using Musify.Domain.Entities;
using Musify.Domain.ValueObjects;
using Musify.Infrastructure.Persistence;
using Xunit;

namespace Musify.Api.Tests.Endpoints
{
    [Collection(ApiCollection.Name)]
    public sealed class GenreEndpointsTests(ApiTestFixture fixture)
    {
        private static readonly JsonSerializerOptions JsonOptions = new(JsonSerializerDefaults.Web)
        {
            Converters = { new JsonStringEnumConverter() }
        };

        private async Task<string> SeedTrackAsync(Genre genre)
        {
            using var scope = fixture.Services.CreateScope();
            var database = scope.ServiceProvider.GetRequiredService<Database>();
            var owner = new User { Id = Random.Shared.NextInt64(1, long.MaxValue), Name = "genre-owner", NormalizedName = "GENRE-OWNER" };
            var title = $"Genre track {Guid.NewGuid():N}";
            var track = new Track
            {
                Title = title,
                NormalizedTitle = title.ToUpperInvariant(),
                OwnerUserId = owner.Id,
                Owner = owner,
                IsPublished = true,
                Tags = [new TrackTag { TrackId = Guid.Empty, Tag = genre }]
            };
            foreach (var tag in track.Tags)
                tag.TrackId = track.Id;
            database.Users.Add(owner);
            database.Tracks.Add(track);
            await database.SaveChangesAsync(TestContext.Current.CancellationToken);
            return title;
        }

        [Fact]
        public async Task GetGenres_Anonymous_ListsGenresInUse()
        {
            await SeedTrackAsync(Genre.Funk);

            var response = await fixture.CreateAnonymousClient().GetAsync("/genres", TestContext.Current.CancellationToken);

            Assert.Equal(HttpStatusCode.OK, response.StatusCode);
            var body = await response.Content.ReadFromJsonAsync<List<GenreResponse>>(JsonOptions, TestContext.Current.CancellationToken);
            Assert.Contains(body!, g => g.Genre == Genre.Funk && g.TrackCount >= 1);
        }

        [Fact]
        public async Task GetAvailableGenres_Anonymous_ListsEveryGenreWithIncompatibilities()
        {
            var response = await fixture.CreateAnonymousClient().GetAsync("/genres/available", TestContext.Current.CancellationToken);

            Assert.Equal(HttpStatusCode.OK, response.StatusCode);
            var body = await response.Content.ReadFromJsonAsync<List<AvailableGenreResponse>>(JsonOptions, TestContext.Current.CancellationToken);
            Assert.Equal(Enum.GetValues<Genre>().Count(genre => genre != Genre.None), body!.Count);
            Assert.Contains(Genre.Lofi, body.Single(g => g.Genre == Genre.Metal).IncompatibleWith);
        }

        [Theory]
        [InlineData("Nope")]
        [InlineData("999")]
        public async Task GetTracks_UnknownGenre_ReturnsBadRequest(string genre)
        {
            var response = await fixture.CreateAnonymousClient().GetAsync($"/tracks?genre={genre}", TestContext.Current.CancellationToken);

            Assert.Equal(HttpStatusCode.BadRequest, response.StatusCode);
        }

        [Fact]
        public async Task GetTracks_GenreQuery_IsCaseInsensitive()
        {
            var title = await SeedTrackAsync(Genre.Blues);

            var response = await fixture.CreateAnonymousClient().GetAsync("/tracks?genre=blues&pageSize=100", TestContext.Current.CancellationToken);

            Assert.Equal(HttpStatusCode.OK, response.StatusCode);
            var body = await response.Content.ReadFromJsonAsync<PaginatedResponse<TrackApplicationResponse>>(JsonOptions, TestContext.Current.CancellationToken);
            Assert.Contains(body!.Items, item => item.Title == title);
        }

        [Fact]
        public async Task GetTracks_GenreQuery_FiltersByTag()
        {
            var title = await SeedTrackAsync(Genre.Ambient);
            await SeedTrackAsync(Genre.Techno);

            var response = await fixture.CreateAnonymousClient().GetAsync("/tracks?genre=Ambient&pageSize=100", TestContext.Current.CancellationToken);

            Assert.Equal(HttpStatusCode.OK, response.StatusCode);
            var body = await response.Content.ReadFromJsonAsync<PaginatedResponse<TrackApplicationResponse>>(JsonOptions, TestContext.Current.CancellationToken);
            Assert.Contains(body!.Items, item => item.Title == title);
            Assert.All(body.Items, item => Assert.Contains(Genre.Ambient, item.Tags));
        }
    }
}