av-parser/tests/AvParser.UI.Tests/ShellViewModelTests.cs

using Avalonia.Controls;
using AvParser.Core.Settings;
using AvParser.UI.Localization;
using AvParser.UI.Navigation;
using AvParser.UI.Responsive;
using AvParser.UI.Tests.Fakes;
using AvParser.UI.ViewModels;
using ReactiveUI.Primitives;
using ReactiveUI.Primitives.Concurrency;

namespace AvParser.UI.Tests;

public class ShellViewModelTests
{
    private static (ShellViewModel Shell, NavigationService Navigation, FakeThemeService Theme) Build(
        AppTheme theme = AppTheme.System
    )
    {
        var navigation = new NavigationService([
            new FakePage("Page.Dashboard"),
            new FakePage("Page.Parse"),
            new OtherFakePage(),
        ]);
        var themeService = new FakeThemeService(theme);

        // ImmediateSequencer makes every derived property settle before the next line runs,
        // which is what lets these read as plain synchronous assertions.
        return (new ShellViewModel(navigation, themeService, ImmediateSequencer.Instance), navigation, themeService);
    }

    [Theory]
    [InlineData(Breakpoint.Expanded, SplitViewDisplayMode.Inline)]
    [InlineData(Breakpoint.Medium, SplitViewDisplayMode.CompactInline)]
    [InlineData(Breakpoint.Compact, SplitViewDisplayMode.Overlay)]
    public void Breakpoint_selects_the_pane_display_mode(Breakpoint breakpoint, SplitViewDisplayMode expected)
    {
        var (shell, _, _) = Build();

        shell.Breakpoint = breakpoint;

        shell.PaneDisplayMode.ShouldBe(expected);
    }

    [Theory]
    [InlineData(Breakpoint.Expanded, true)]
    [InlineData(Breakpoint.Medium, false)]
    [InlineData(Breakpoint.Compact, false)]
    public void Crossing_a_breakpoint_resets_the_pane(Breakpoint breakpoint, bool expectedOpen)
    {
        var (shell, _, _) = Build();

        shell.Breakpoint = breakpoint;

        shell.IsPaneOpen.ShouldBe(expectedOpen);
    }

    [Fact]
    public void A_manual_toggle_survives_until_the_next_breakpoint_change()
    {
        var (shell, _, _) = Build();
        shell.Breakpoint = Breakpoint.Compact;

        shell.TogglePaneCommand.Execute().Subscribe(_ => { });
        shell.IsPaneOpen.ShouldBeTrue();

        shell.Breakpoint = Breakpoint.Expanded;
        shell.IsPaneOpen.ShouldBeTrue();

        shell.Breakpoint = Breakpoint.Compact;
        shell.IsPaneOpen.ShouldBeFalse();
    }

    [Fact]
    public void Choosing_a_destination_dismisses_the_compact_drawer()
    {
        var (shell, _, _) = Build();
        shell.Breakpoint = Breakpoint.Compact;
        shell.TogglePaneCommand.Execute().Subscribe(_ => { });
        shell.IsPaneOpen.ShouldBeTrue();

        shell.SelectedPage = shell.Pages[1];

        shell.IsPaneOpen.ShouldBeFalse();
    }

    [Fact]
    public void Choosing_a_destination_leaves_the_expanded_sidebar_open()
    {
        var (shell, _, _) = Build();
        shell.Breakpoint = Breakpoint.Expanded;

        shell.SelectedPage = shell.Pages[1];

        shell.IsPaneOpen.ShouldBeTrue();
    }

    [Fact]
    public void Selecting_a_page_navigates_to_it()
    {
        var (shell, navigation, _) = Build();

        shell.SelectedPage = shell.Pages[2];

        navigation.Current.ShouldBeSameAs(shell.Pages[2]);
        shell.CurrentPage.ShouldBeSameAs(shell.Pages[2]);
        shell.Title.ShouldBe(Localizer.Instance["Page.About"]);
    }

    [Fact]
    public void Navigating_from_elsewhere_updates_the_rail_selection()
    {
        var (shell, navigation, _) = Build();

        navigation.NavigateTo<OtherFakePage>();

        shell.SelectedPage.ShouldBeSameAs(navigation.Current);
    }

    [Fact]
    public void Back_is_disabled_until_something_is_on_the_stack()
    {
        var (shell, _, _) = Build();

        shell.CanGoBack.ShouldBeFalse();

        shell.SelectedPage = shell.Pages[1];

        shell.CanGoBack.ShouldBeTrue();
    }

    [Fact]
    public void Back_returns_to_the_previous_page()
    {
        var (shell, _, _) = Build();
        var first = shell.Pages[0];
        shell.SelectedPage = shell.Pages[1];

        shell.GoBackCommand.Execute().Subscribe(_ => { });

        shell.CurrentPage.ShouldBeSameAs(first);
        shell.SelectedPage.ShouldBeSameAs(first);
    }

    [Theory]
    [InlineData(AppTheme.Dark, AppTheme.Light)]
    [InlineData(AppTheme.Light, AppTheme.Dark)]
    [InlineData(AppTheme.System, AppTheme.Dark)]
    public void Toggling_the_theme_flips_between_light_and_dark(AppTheme start, AppTheme expected)
    {
        var (shell, _, theme) = Build(start);

        shell.ToggleThemeCommand.Execute().Subscribe(_ => { });

        theme.Current.ShouldBe(expected);
    }

    [Fact]
    public void The_theme_button_shows_the_theme_it_would_switch_to()
    {
        var (shell, _, theme) = Build(AppTheme.Light);

        shell.ThemeIconKey.ShouldBe("IconMoon");

        theme.Apply(AppTheme.Dark);

        shell.ThemeIconKey.ShouldBe("IconSun");
    }
}