LehrerApp/LehrerApp.Desktop.Tests/AppearanceSettingsServiceTests.cs

using LehrerApp.Desktop.Services;
using Xunit;

namespace LehrerApp.Desktop.Tests;

public sealed class AppearanceSettingsServiceTests
{
    private static string BuildTempPath()
    {
        var path = Path.Combine(Path.GetTempPath(), $"lehrerapp-appearance-tests-{Guid.NewGuid():N}");
        Directory.CreateDirectory(path);
        return path;
    }

    [Fact]
    public void Load_OhneVorhandeneDatei_LiefertSystemvorgabe() =>
        Assert.Equal(AppTheme.System, new AppearanceSettingsService(BuildTempPath()).Load());

    [Theory]
    [InlineData(AppTheme.Light)]
    [InlineData(AppTheme.Dark)]
    [InlineData(AppTheme.System)]
    public void SaveUndLoad_PersistiertUeberNeueInstanz(AppTheme theme)
    {
        var path = BuildTempPath();
        new AppearanceSettingsService(path).Save(theme);

        var reloaded = new AppearanceSettingsService(path).Load();

        Assert.Equal(theme, reloaded);
    }

    [Fact]
    public void Load_BeschaedigteDatei_FaelltAufSystemvorgabeZurueck()
    {
        var path = BuildTempPath();
        File.WriteAllText(Path.Combine(path, "appearancesettings.json"), "{ kein json");

        Assert.Equal(AppTheme.System, new AppearanceSettingsService(path).Load());
    }
}

public sealed class AppThemeDisplayTests
{
    [Theory]
    [InlineData(AppTheme.System, "Systemvorgabe")]
    [InlineData(AppTheme.Light, "Hell")]
    [InlineData(AppTheme.Dark, "Dunkel")]
    public void Label_LiefertDeutscheBeschriftung(AppTheme theme, string expected) =>
        Assert.Equal(expected, AppThemeDisplay.Label(theme));

    [Fact]
    public void FromLabel_UndLabel_SindZueinanderInvers()
    {
        foreach (var theme in Enum.GetValues<AppTheme>())
            Assert.Equal(theme, AppThemeDisplay.FromLabel(AppThemeDisplay.Label(theme)));
    }

    [Fact]
    public void FromLabel_UnbekanntesLabel_LiefertSystemvorgabe() =>
        Assert.Equal(AppTheme.System, AppThemeDisplay.FromLabel("Nonsens"));
}