using System.Collections.Specialized;

namespace NeumUI.Controls;

/// <summary>
/// 面包屑
/// </summary>
[StyleTypedProperty(Property = "ItemContainerStyle", StyleTargetType = typeof(BreadcrumbItem))]
public class Breadcrumb : ItemsControl
{
    #region 事件

    /// <summary>
    /// 导航
    /// </summary>
    public static readonly RoutedEvent NavigateEvent = EventManager.RegisterRoutedEvent(
        "Navigate",
        RoutingStrategy.Direct,
        typeof(RoutedPropertyChangedEventHandler<string>),
        typeof(Breadcrumb));

    /// <summary>
    /// 导航
    /// </summary>
    public event RoutedPropertyChangedEventHandler<string> Navigate
    {
        add => AddHandler(NavigateEvent, value);
        remove => RemoveHandler(NavigateEvent, value);
    }
    #endregion

    #region 属性

    /// <summary>
    /// 链接
    /// </summary>
    public static readonly DependencyProperty HrefProperty =
        DependencyProperty.Register(
        nameof(Href),
        typeof(string),
        typeof(Breadcrumb),
        new FrameworkPropertyMetadata(string.Empty));

    /// <summary>
    /// 链接
    /// </summary>
    public string Href { get => (string)GetValue(HrefProperty);
        set => SetValue(HrefProperty, value);
    }

    /// <summary>
    /// 分隔符
    /// </summary>
    public static readonly DependencyProperty SeparatorProperty =
        DependencyProperty.Register(nameof(Separator), typeof(string), typeof(Breadcrumb), new FrameworkPropertyMetadata("/"));

    /// <summary>
    /// 分隔符
    /// </summary>
    public string Separator
    {
        get => (string)GetValue(SeparatorProperty);
        set => SetValue(SeparatorProperty, value);
    }

    /// <summary>
    /// 分隔符颜色
    /// </summary>
    public static readonly DependencyProperty SeparatorBrushProperty =
        DependencyProperty.Register(
        nameof(SeparatorBrush),
        typeof(Brush),
        typeof(Breadcrumb),
        new FrameworkPropertyMetadata(null));

    /// <summary>
    /// 分隔符颜色
    /// </summary>
    public Brush SeparatorBrush
    {
        get => (Brush)GetValue(SeparatorBrushProperty);
        set => SetValue(SeparatorBrushProperty, value);
    }
    #endregion

    static Breadcrumb()
    { DefaultStyleKeyProperty.OverrideMetadata(typeof(Breadcrumb), new FrameworkPropertyMetadata(typeof(Breadcrumb))); }

    /// <inheritdoc/>
    protected override bool IsItemItsOwnContainerOverride(object item) { return item is BreadcrumbItem; }

    /// <inheritdoc/>
    protected override DependencyObject GetContainerForItemOverride() { return new BreadcrumbItem(); }

    /// <inheritdoc/>
    public override void OnApplyTemplate()
    {
        base.OnApplyTemplate();

        Loaded += Breadcrumb_Loaded;
    }

    private void Breadcrumb_Loaded(object sender, RoutedEventArgs e)
    {
        Loaded -= Breadcrumb_Loaded;

        for(var i = 0; i < Items.Count; i++)
        {
            if(ItemContainerGenerator.ContainerFromIndex(i) is BreadcrumbItem breadcrumbItem)
            {
                breadcrumbItem.Navigate += BreadcrumbItem_Navigate;
            }
        }
    }

    /// <inheritdoc/>
    protected override void OnItemsChanged(NotifyCollectionChangedEventArgs e)
    {
        base.OnItemsChanged(e);

        if(e.OldItems is { })
        {
            foreach(var item in e.NewItems.OfType<BreadcrumbItem>())
            {
                item.Navigate += BreadcrumbItem_Navigate;
            }

            foreach(var item in e.OldItems.OfType<BreadcrumbItem>())
            {
                item.Navigate -= BreadcrumbItem_Navigate;
            }
        }
    }

    private void BreadcrumbItem_Navigate(object sender, RoutedPropertyChangedEventArgs<string> e)
    {
        RaiseEvent(new RoutedPropertyChangedEventArgs<string>(Href, e.NewValue) { RoutedEvent = NavigateEvent });

        Href = e.NewValue;
    }
}

/// <summary>
/// 面包屑子项
/// </summary>
public class BreadcrumbItem : Button
{
    static BreadcrumbItem()
    {
        DefaultStyleKeyProperty.OverrideMetadata(
            typeof(BreadcrumbItem),
            new FrameworkPropertyMetadata(typeof(BreadcrumbItem)));
    }

    #region 事件

    /// <summary>
    /// 导航
    /// </summary>
    public static readonly RoutedEvent NavigateEvent = EventManager.RegisterRoutedEvent(
        "Navigate",
        RoutingStrategy.Direct,
        typeof(RoutedPropertyChangedEventHandler<string>),
        typeof(BreadcrumbItem));

    /// <summary>
    /// 导航
    /// </summary>
    public event RoutedPropertyChangedEventHandler<string> Navigate
    {
        add => AddHandler(NavigateEvent, value);
        remove => RemoveHandler(NavigateEvent, value);
    }
    #endregion

    #region 属性

    /// <summary>
    /// 链接
    /// </summary>
    public static readonly DependencyProperty HrefProperty =
        DependencyProperty.Register(
        nameof(Href),
        typeof(string),
        typeof(BreadcrumbItem),
        new FrameworkPropertyMetadata(string.Empty));

    /// <summary>
    /// 链接
    /// </summary>
    public string Href
    {
        get => (string)GetValue(HrefProperty);
        set => SetValue(HrefProperty, value);
    }

    /// <summary>
    /// 分隔符
    /// </summary>
    public static readonly DependencyProperty SeparatorProperty =
        DependencyProperty.Register(
        nameof(Separator),
        typeof(string),
        typeof(BreadcrumbItem),
        new FrameworkPropertyMetadata("/"));

    /// <summary>
    /// 分隔符
    /// </summary>
    public string Separator
    {
        get => (string)GetValue(SeparatorProperty);
        set => SetValue(SeparatorProperty, value);
    }

    /// <summary>
    /// 分隔符颜色
    /// </summary>
    public static readonly DependencyProperty SeparatorBrushProperty =
        DependencyProperty.Register(
        nameof(SeparatorBrush),
        typeof(Brush),
        typeof(BreadcrumbItem),
        new FrameworkPropertyMetadata(null));

    /// <summary>
    /// 分隔符颜色
    /// </summary>
    public Brush SeparatorBrush
    {
        get => (Brush)GetValue(SeparatorBrushProperty);
        set => SetValue(SeparatorBrushProperty, value);
    }
    #endregion

    /// <inheritdoc/>
    protected override void OnClick()
    {
        base.OnClick();

        RaiseEvent(new RoutedPropertyChangedEventArgs<string>(null, Href) { RoutedEvent = NavigateEvent });
    }
}