using Avalonia;
using Avalonia.Controls;

namespace DodoSSH.Client.App.Views;

/// <summary>
/// The screen behind a nav-rail entry whose feature does not exist yet.
/// </summary>
/// <remarks>
/// <para>
/// Styled properties set from XAML rather than a view model, because there is no state here — a screen
/// saying what is absent has nothing to observe, and a view model per absent feature would be two classes
/// whose only job is to hold four strings.
/// </para>
/// <para>
/// <see cref="Missing"/> takes the list rather than the markup listing it inline, so the two instances of
/// this control differ only in their content and the layout is written once.
/// </para>
/// </remarks>
internal sealed partial class NotBuiltScreen : UserControl
{
    /// <summary>What the feature is called, in the design's own words.</summary>
    public static readonly StyledProperty<string> TitleProperty =
        AvaloniaProperty.Register<NotBuiltScreen, string>(nameof(Title), string.Empty);

    /// <summary>Which milestone it belongs to, so the chip is a fact and not an apology.</summary>
    public static readonly StyledProperty<string> MilestoneProperty =
        AvaloniaProperty.Register<NotBuiltScreen, string>(nameof(Milestone), string.Empty);

    /// <summary>One paragraph on what the design shows and why none of it is here.</summary>
    public static readonly StyledProperty<string> SummaryProperty =
        AvaloniaProperty.Register<NotBuiltScreen, string>(nameof(Summary), string.Empty);

    /// <summary>The specific pieces, each naming the layer it would land in.</summary>
    public static readonly StyledProperty<IEnumerable<string>?> MissingProperty =
        AvaloniaProperty.Register<NotBuiltScreen, IEnumerable<string>?>(nameof(Missing));

    /// <summary>What somebody wanting this today should do instead.</summary>
    public static readonly StyledProperty<string> InsteadProperty =
        AvaloniaProperty.Register<NotBuiltScreen, string>(nameof(Instead), string.Empty);

    public NotBuiltScreen()
    {
        InitializeComponent();

        // Bound in code rather than in the markup, because the markup's own DataContext is the shell and
        // these five are properties of this control. Self-bindings in XAML would need a relative source on
        // every one of them, which is five chances to point one at the wrong object.
        TitleText.Bind(TextBlock.TextProperty, this.GetObservable(TitleProperty));
        MilestoneText.Bind(TextBlock.TextProperty, this.GetObservable(MilestoneProperty));
        SummaryText.Bind(TextBlock.TextProperty, this.GetObservable(SummaryProperty));
        InsteadText.Bind(TextBlock.TextProperty, this.GetObservable(InsteadProperty));
        MissingList.Bind(ItemsControl.ItemsSourceProperty, this.GetObservable(MissingProperty));
    }

    /// <inheritdoc cref="TitleProperty" />
    public string Title
    {
        get => GetValue(TitleProperty);
        set => SetValue(TitleProperty, value);
    }

    /// <inheritdoc cref="MilestoneProperty" />
    public string Milestone
    {
        get => GetValue(MilestoneProperty);
        set => SetValue(MilestoneProperty, value);
    }

    /// <inheritdoc cref="SummaryProperty" />
    public string Summary
    {
        get => GetValue(SummaryProperty);
        set => SetValue(SummaryProperty, value);
    }

    /// <inheritdoc cref="MissingProperty" />
    public IEnumerable<string>? Missing
    {
        get => GetValue(MissingProperty);
        set => SetValue(MissingProperty, value);
    }

    /// <inheritdoc cref="InsteadProperty" />
    public string Instead
    {
        get => GetValue(InsteadProperty);
        set => SetValue(InsteadProperty, value);
    }
}