#nullable disable
using System;
using System.Collections.Specialized;
using System.ComponentModel;
 
namespace Microsoft.Maui.Controls.Shapes
{
	/// <include file="../../../docs/Microsoft.Maui.Controls.Shapes/GeometryGroup.xml" path="Type[@FullName='Microsoft.Maui.Controls.Shapes.GeometryGroup']/Docs/*" />
	[ContentProperty("Children")]
	public class GeometryGroup : Geometry
	{
		/// <summary>Bindable property for <see cref="Children"/>.</summary>
		public static readonly BindableProperty ChildrenProperty =
			BindableProperty.Create(nameof(Children), typeof(GeometryCollection), typeof(GeometryGroup), null,
				propertyChanged: OnChildrenChanged);
 
		static void OnChildrenChanged(BindableObject bindable, object oldValue, object newValue)
		{
			(bindable as GeometryGroup)?.UpdateChildren(oldValue as GeometryCollection, newValue as GeometryCollection);
		}
 
		/// <summary>Bindable property for <see cref="FillRule"/>.</summary>
		public static readonly BindableProperty FillRuleProperty =
			BindableProperty.Create(nameof(FillRule), typeof(FillRule), typeof(GeometryGroup), FillRule.EvenOdd);
 
		/// <include file="../../../docs/Microsoft.Maui.Controls.Shapes/GeometryGroup.xml" path="//Member[@MemberName='.ctor']/Docs/*" />
		public GeometryGroup()
		{
			Children = new GeometryCollection();
		}
 
		/// <include file="../../../docs/Microsoft.Maui.Controls.Shapes/GeometryGroup.xml" path="//Member[@MemberName='Children']/Docs/*" />
		public GeometryCollection Children
		{
			set { SetValue(ChildrenProperty, value); }
			get { return (GeometryCollection)GetValue(ChildrenProperty); }
		}
 
		/// <include file="../../../docs/Microsoft.Maui.Controls.Shapes/GeometryGroup.xml" path="//Member[@MemberName='FillRule']/Docs/*" />
		public FillRule FillRule
		{
			set { SetValue(FillRuleProperty, value); }
			get { return (FillRule)GetValue(FillRuleProperty); }
		}
 
		public event EventHandler InvalidateGeometryRequested;
 
		void UpdateChildren(GeometryCollection oldCollection, GeometryCollection newCollection)
		{
			if (oldCollection != null)
			{
				oldCollection.CollectionChanged -= OnChildrenCollectionChanged;
 
				foreach (var oldChildren in oldCollection)
				{
					oldChildren.PropertyChanged -= OnChildrenPropertyChanged;
				}
			}
 
			if (newCollection == null)
				return;
 
			newCollection.CollectionChanged += OnChildrenCollectionChanged;
 
			foreach (var newChildren in newCollection)
			{
				newChildren.PropertyChanged += OnChildrenPropertyChanged;
			}
		}
 
		void OnChildrenCollectionChanged(object sender, NotifyCollectionChangedEventArgs e)
		{
			if (e.OldItems != null)
			{
				foreach (var oldItem in e.OldItems)
				{
					if (!(oldItem is Geometry oldGeometry))
						continue;
 
					oldGeometry.PropertyChanged -= OnChildrenPropertyChanged;
				}
			}
 
			if (e.NewItems != null)
			{
				foreach (var newItem in e.NewItems)
				{
					if (!(newItem is Geometry newGeometry))
						continue;
 
					newGeometry.PropertyChanged += OnChildrenPropertyChanged;
				}
			}
 
			Invalidate();
		}
 
		void OnChildrenPropertyChanged(object sender, PropertyChangedEventArgs e)
		{
			Invalidate();
		}
 
		void Invalidate()
		{
			InvalidateGeometryRequested?.Invoke(this, EventArgs.Empty);
		}
 
		public override void AppendPath(Graphics.PathF path)
		{
			foreach (var c in Children)
			{
				c.AppendPath(path);
			}
		}
	}
}