deepdrft/DeepDrftTests/SeoModelTests.cs

using System.Text.Json;
using DeepDrftModels.DTOs;
using DeepDrftModels.Enums;
using DeepDrftPublic.Client.Common;

namespace DeepDrftTests;

/// <summary>
/// Unit tests for the Phase 22 SEO typed builders (<see cref="SeoModel"/> factories + <see cref="SeoJsonLd"/>
/// nodes + <see cref="SeoUrls"/>). These are pure functions over the DTOs a page already holds — the
/// medium→schema mapping (AC3), graceful partial data (AC4), JSON-LD validity (AC5), and canonical
/// correctness (AC7) are all testable here without rendering. The JSON-LD is parsed back to a document so
/// each assertion checks real structure, not a substring.
/// </summary>
[TestFixture]
public class SeoModelTests
{
    private static readonly SeoOptions Options = new()
    {
        BaseUrl = "https://deepdrft.com",
        SiteName = "Deep DRFT",
        TitleSuffix = "Deep DRFT",
        DefaultDescription = "default description",
        DefaultImageUrl = "/img/og-default.png",
        Genre = "Electronic",
        SameAs = ["https://instagram.com/deepdrft.music"],
    };

    private static ReleaseDto Release(ReleaseMedium medium, string? image = "cover.jpg", string? description = "desc") => new()
    {
        EntryKey = "abc-key",
        Title = "Test Release",
        Artist = "Deep DRFT",
        Genre = "House",
        Description = description,
        ImagePath = image,
        ReleaseDate = new DateOnly(2026, 3, 14),
        Medium = medium,
    };

    private static JsonElement Parse(string? json)
    {
        Assert.That(json, Is.Not.Null.And.Not.Empty, "expected a JSON-LD body");
        return JsonDocument.Parse(json!).RootElement;
    }

    // --- AC3: per-medium schema -------------------------------------------------

    [Test]
    public void ForRelease_Cut_IsMusicAlbum_StudioAlbum_WithOrderedTrackList()
    {
        var tracks = new List<TrackDto>
        {
            new() { TrackName = "Second", TrackNumber = 2, DurationSeconds = 60 },
            new() { TrackName = "First", TrackNumber = 1, DurationSeconds = 30 },
        };

        var model = SeoModel.ForRelease(Options, Release(ReleaseMedium.Cut), tracks);
        var node = Parse(model.JsonLd);

        Assert.Multiple(() =>
        {
            Assert.That(node.GetProperty("@type").GetString(), Is.EqualTo("MusicAlbum"));
            Assert.That(node.GetProperty("albumProductionType").GetString(), Is.EqualTo("https://schema.org/StudioAlbum"));
            Assert.That(model.OgType, Is.EqualTo(SeoOgType.MusicAlbum));

            var trackArray = node.GetProperty("track");
            Assert.That(trackArray.GetArrayLength(), Is.EqualTo(2));
            // Ordered by TrackNumber, not input order.
            Assert.That(trackArray[0].GetProperty("name").GetString(), Is.EqualTo("First"));
            Assert.That(trackArray[1].GetProperty("name").GetString(), Is.EqualTo("Second"));
            Assert.That(trackArray[0].GetProperty("duration").GetString(), Is.EqualTo("PT30S"));
        });
    }

    [Test]
    public void ForRelease_Session_IsMusicAlbum_LiveAlbum()
    {
        var model = SeoModel.ForRelease(Options, Release(ReleaseMedium.Session));
        var node = Parse(model.JsonLd);

        Assert.Multiple(() =>
        {
            Assert.That(node.GetProperty("@type").GetString(), Is.EqualTo("MusicAlbum"));
            Assert.That(node.GetProperty("albumProductionType").GetString(), Is.EqualTo("https://schema.org/LiveAlbum"));
            Assert.That(model.OgType, Is.EqualTo(SeoOgType.MusicAlbum));
        });
    }

    [Test]
    public void ForRelease_Mix_IsMusicRecording_WithIsoDuration()
    {
        var tracks = new List<TrackDto> { new() { TrackName = "The Mix", DurationSeconds = 3723 } }; // 1h 2m 3s
        var model = SeoModel.ForRelease(Options, Release(ReleaseMedium.Mix), tracks);
        var node = Parse(model.JsonLd);

        Assert.Multiple(() =>
        {
            Assert.That(node.GetProperty("@type").GetString(), Is.EqualTo("MusicRecording"));
            Assert.That(node.GetProperty("duration").GetString(), Is.EqualTo("PT1H2M3S"));
            Assert.That(model.OgType, Is.EqualTo(SeoOgType.MusicSong));
            Assert.That(model.DurationSeconds, Is.EqualTo(3723));
            // A mix is one recording, not an album — it carries no track list.
            Assert.That(node.TryGetProperty("track", out _), Is.False);
        });
    }

    [Test]
    public void ForRelease_AllNodes_DeclareSchemaOrgContext()
    {
        foreach (var medium in Enum.GetValues<ReleaseMedium>())
        {
            var node = Parse(SeoModel.ForRelease(Options, Release(medium)).JsonLd);
            Assert.That(node.GetProperty("@context").GetString(), Is.EqualTo("https://schema.org"),
                $"{medium} node must declare the schema.org context");
        }
    }

    // --- AC4: graceful partial data ---------------------------------------------

    [Test]
    public void ForRelease_NoDescription_FallsBackToDefault()
    {
        var model = SeoModel.ForRelease(Options, Release(ReleaseMedium.Cut, description: null));
        Assert.That(model.Description, Is.EqualTo(Options.DefaultDescription));
    }

    [Test]
    public void ForRelease_NoCover_OmitsImagePath_SoHeadFallsBackToDefault()
    {
        var model = SeoModel.ForRelease(Options, Release(ReleaseMedium.Cut, image: null));
        // The model carries no relative ImagePath; the JSON-LD image is absolutised to the default.
        var node = Parse(model.JsonLd);

        Assert.Multiple(() =>
        {
            Assert.That(model.ImagePath, Is.Null);
            Assert.That(node.GetProperty("image").GetString(), Is.EqualTo("https://deepdrft.com/img/og-default.png"));
        });
    }

    [Test]
    public void ForRelease_NoGenre_OmitsGenreProperty_NoEmptyValue()
    {
        var release = Release(ReleaseMedium.Cut);
        release.Genre = null;

        var node = Parse(SeoModel.ForRelease(Options, release).JsonLd);
        Assert.That(node.TryGetProperty("genre", out _), Is.False, "a null genre must be omitted, not emitted empty");
    }

    [Test]
    public void ForRelease_Mix_NoTrack_OmitsDuration()
    {
        var node = Parse(SeoModel.ForRelease(Options, Release(ReleaseMedium.Mix), tracks: null).JsonLd);
        Assert.That(node.TryGetProperty("duration", out _), Is.False, "a mix with no track must omit duration");
    }

    // --- AC7: canonical correctness ---------------------------------------------

    [TestCase(ReleaseMedium.Cut, "https://deepdrft.com/cuts/abc-key")]
    [TestCase(ReleaseMedium.Session, "https://deepdrft.com/sessions/abc-key")]
    [TestCase(ReleaseMedium.Mix, "https://deepdrft.com/mixes/abc-key")]
    public void ForRelease_CanonicalPath_IsDedicatedRoute_AndJsonLdUrlAgrees(ReleaseMedium medium, string expectedAbsolute)
    {
        var model = SeoModel.ForRelease(Options, Release(medium));
        var node = Parse(model.JsonLd);

        Assert.Multiple(() =>
        {
            Assert.That(SeoUrls.Absolute(Options, model.CanonicalPath!), Is.EqualTo(expectedAbsolute));
            // The JSON-LD url must be the same absolute canonical (AC7: canonical == og:url == node url).
            Assert.That(node.GetProperty("url").GetString(), Is.EqualTo(expectedAbsolute));
        });
    }

    // --- Home / About / Browse / NotFound ---------------------------------------

    [Test]
    public void ForHome_IsMusicGroup_WithSameAs()
    {
        var model = SeoModel.ForHome(Options);
        var node = Parse(model.JsonLd);

        Assert.Multiple(() =>
        {
            Assert.That(node.GetProperty("@type").GetString(), Is.EqualTo("MusicGroup"));
            Assert.That(node.GetProperty("name").GetString(), Is.EqualTo("Deep DRFT"));
            Assert.That(node.GetProperty("sameAs")[0].GetString(), Is.EqualTo("https://instagram.com/deepdrft.music"));
            Assert.That(model.CanonicalPath, Is.EqualTo("/"));
        });
    }

    [Test]
    public void ForAbout_IsMusicGroup()
    {
        var node = Parse(SeoModel.ForAbout(Options).JsonLd);
        Assert.That(node.GetProperty("@type").GetString(), Is.EqualTo("MusicGroup"));
    }

    [TestCase(ReleaseMedium.Cut, "/cuts")]
    [TestCase(ReleaseMedium.Session, "/sessions")]
    [TestCase(ReleaseMedium.Mix, "/mixes")]
    public void ForBrowse_IsCollectionPage_WithAbsoluteUrl(ReleaseMedium medium, string path)
    {
        var model = SeoModel.ForBrowse(Options, medium, path);
        var node = Parse(model.JsonLd);

        Assert.Multiple(() =>
        {
            Assert.That(node.GetProperty("@type").GetString(), Is.EqualTo("CollectionPage"));
            Assert.That(node.GetProperty("url").GetString(), Is.EqualTo($"https://deepdrft.com{path}"));
            Assert.That(model.CanonicalPath, Is.EqualTo(path));
        });
    }

    [Test]
    public void ForBrowse_NullMedium_IsArchive()
    {
        var model = SeoModel.ForBrowse(Options, null, "/archive");
        Assert.That(model.Title, Is.EqualTo("Archive"));
    }

    [Test]
    public void ForNotFound_IsNoindex_NoCanonical_NoJsonLd()
    {
        var model = SeoModel.ForNotFound(Options);

        Assert.Multiple(() =>
        {
            Assert.That(model.Robots, Is.EqualTo("noindex,follow"));
            Assert.That(model.CanonicalPath, Is.Null);
            Assert.That(model.JsonLd, Is.Null);
        });
    }
}