/* Based on VirtualizingWrapPanel created by S. Bäumlisberger licensed under MIT license.
   https://github.com/sbaeumlisberger/VirtualizingWrapPanel

   Copyright (C) S. Bäumlisberger
   All Rights Reserved. */

using System.Windows.Controls;
using System.Windows.Data;

// ReSharper disable once CheckNamespace
namespace WPFluent.Controls;

/// <summary>
/// Simple control that displays a gird of items. Depending on the orientation, the items are either stacked
/// horizontally or vertically until the items are wrapped to the next row or column. The control is using
/// virtualization to support large amount of items. <para>In order to work properly all items must have the same
/// size.</para> <para>Based on <see href="https://github.com/sbaeumlisberger/VirtualizingWrapPanel"/>.</para>
/// </summary>
public class VirtualizingGridView : System.Windows.Controls.ListView
{
    /// <summary>
    /// Identifies the <see cref="Orientation"/> dependency property.
    /// </summary>
    public static readonly DependencyProperty OrientationProperty = DependencyProperty.Register(
        nameof(Orientation),
        typeof(Orientation),
        typeof(VirtualizingGridView),
        new PropertyMetadata(Orientation.Vertical));

    /// <summary>
    /// Identifies the <see cref="SpacingMode"/> dependency property.
    /// </summary>
    public static readonly DependencyProperty SpacingModeProperty = DependencyProperty.Register(
        nameof(SpacingMode),
        typeof(SpacingMode),
        typeof(VirtualizingGridView),
        new PropertyMetadata(SpacingMode.Uniform));

    /// <summary>
    /// Identifies the <see cref="StretchItems"/> dependency property.
    /// </summary>
    public static readonly DependencyProperty StretchItemsProperty = DependencyProperty.Register(
        nameof(StretchItems),
        typeof(bool),
        typeof(VirtualizingGridView),
        new PropertyMetadata(false));

    public VirtualizingGridView()
    {
        VirtualizingPanel.SetCacheLengthUnit(this, VirtualizationCacheLengthUnit.Page);
        VirtualizingPanel.SetCacheLength(this, new VirtualizationCacheLength(1));
        VirtualizingPanel.SetIsVirtualizingWhenGrouping(this, true);
    }

    /// <summary>
    /// Initializes the <see cref="ItemsControl.ItemsPanel"/> with <see cref="VirtualizingWrapPanel"/>.
    /// </summary>
    protected virtual void InitializeItemsPanel()
    {
        var factory = new FrameworkElementFactory(typeof(VirtualizingWrapPanel));

        factory.SetBinding(
            VirtualizingWrapPanel.OrientationProperty,
            new Binding { Source = this, Path = new PropertyPath(nameof(Orientation)), Mode = BindingMode.OneWay, });
        factory.SetBinding(
            VirtualizingWrapPanel.SpacingModeProperty,
            new Binding { Source = this, Path = new PropertyPath(nameof(SpacingMode)), Mode = BindingMode.OneWay, });
        factory.SetBinding(
            VirtualizingWrapPanel.StretchItemsProperty,
            new Binding { Source = this, Path = new PropertyPath(nameof(StretchItems)), Mode = BindingMode.OneWay, });

        SetCurrentValue(ItemsPanelProperty, new ItemsPanelTemplate(factory));
    }

    protected override void OnInitialized(EventArgs e)
    {
        base.OnInitialized(e);

        InitializeItemsPanel();
    }

    /// <summary>
    /// Gets or sets a value that specifies the orientation in which items are arranged. The default value is <see
    /// cref="Orientation.Vertical"/>.
    /// </summary>
    public Orientation Orientation
    {
        get => (Orientation)GetValue(OrientationProperty);
        set => SetValue(OrientationProperty, value);
    }

    /// <summary>
    /// Gets or sets the spacing mode used when arranging the items. The default value is <see
    /// cref="SpacingMode.Uniform"/>.
    /// </summary>
    public SpacingMode SpacingMode
    {
        get => (SpacingMode)GetValue(SpacingModeProperty);
        set => SetValue(SpacingModeProperty, value);
    }

    /// <summary>
    /// Gets or sets a value indicating whether the items get stretched to fill up remaining space. The default value is
    /// false.
    /// </summary>
    /// <remarks>
    /// The MaxWidth and MaxHeight properties of the ItemContainerStyle can be used to limit the stretching. In this
    /// case the use of the remaining space will be determined by the SpacingMode property.
    /// </remarks>
    public bool StretchItems
    {
        get => (bool)GetValue(StretchItemsProperty);
        set => SetValue(StretchItemsProperty, value);
    }
}