XiuXianGame/Assets/AmplifyShaderEditor/Plugins/Editor/Utils/WindowHelper.cs

#if UNITY_EDITOR
using System;
using System.Reflection;
using UnityEditor;
using UnityEngine;

namespace AmplifyShaderEditor
{
	public static class WindowHelper
	{
		private class R_EditorWindow
		{
			private EditorWindow m_instance;
			private System.Type m_type;

			public R_EditorWindow( EditorWindow instance )
			{
				m_instance = instance;
				m_type = instance.GetType();
			}

			public object Parent
			{
				get
				{
					var field = m_type.GetField( "m_Parent", BindingFlags.Instance | BindingFlags.NonPublic );
					return field.GetValue( m_instance );
				}
			}

			public object Docked
			{
				get
				{
					var property = m_type.GetProperty( "docked", BindingFlags.Instance | BindingFlags.NonPublic );
					return property.GetValue( m_instance, null );
				}
			}
		}

		private class R_DockArea
		{
			private object m_instance;
			private System.Type m_type;

			public R_DockArea( object instance )
			{
				m_instance = instance;
				m_type = instance.GetType();
			}

			public object Window
			{
				get
				{
					var property = m_type.GetProperty( "window", BindingFlags.Instance | BindingFlags.Public );
					return property.GetValue( m_instance, null );
				}
			}

			public object ActualView
			{
				get
				{
					var field = m_type.GetField( "m_ActualView", BindingFlags.Instance | BindingFlags.NonPublic );
					return field.GetValue( m_instance );
				}
			}

			public object OriginalDragSource
			{
				set
				{
					var field = m_type.GetField( "s_OriginalDragSource", BindingFlags.Static | BindingFlags.NonPublic );
					field.SetValue( null, value );
				}
			}


			public void AddTab( EditorWindow pane )
			{
				var method = m_type.GetMethod( "AddTab", BindingFlags.Instance | BindingFlags.Public, null, new System.Type[] { typeof( EditorWindow ), typeof( bool ) }, null );
				if( method != null )
					method.Invoke( m_instance, new object[] { pane, true } );
			}

			public void RemoveTab( EditorWindow pane )
			{
				if( !pane.maximized )
				{
					var method = m_type.GetMethod( "RemoveTab", BindingFlags.Instance | BindingFlags.Public, null, new System.Type[] { typeof( EditorWindow ) }, null );
					if( method != null )
						method.Invoke( m_instance, new object[] { pane } );
				}
			}
		}

		private class R_ContainerWindow
		{
			private object m_instance;
			private System.Type m_type;

			public R_ContainerWindow( object instance )
			{
				m_instance = instance;
				m_type = instance.GetType();
			}

			public object RootSplitView
			{
				get
				{
					var property = m_type.GetProperty( "rootSplitView", BindingFlags.Instance | BindingFlags.Public );
					return property.GetValue( m_instance, null );
				}
			}

			public object RootView
			{
				get
				{
					var property = m_type.GetProperty( "rootView", BindingFlags.Instance | BindingFlags.Public );
					return property.GetValue( m_instance, null );
				}
			}

			public object WindowPtr
			{
				get
				{
					var all = m_type.GetNestedTypes();
					foreach( var item in all )
					{
						Debug.Log( item.Name );
					}
					var property = m_type.GetField( "m_WindowPtr", BindingFlags.Instance | BindingFlags.NonPublic );
					return property.GetValue( m_instance );
				}
			}
		}

		private class R_SplitView
		{
			private object m_instance;
			private System.Type m_type;

			public R_SplitView( object instance )
			{
				m_instance = instance;
				m_type = instance.GetType();
			}

			public object DragOver( EditorWindow child, Vector2 screenPoint )
			{
				var method = m_type.GetMethod( "DragOver", BindingFlags.Instance | BindingFlags.Public );
				return method.Invoke( m_instance, new object[] { child, screenPoint } );
			}

			public void PerformDrop( EditorWindow child, object dropInfo, Vector2 screenPoint )
			{
				var method = m_type.GetMethod( "PerformDrop", BindingFlags.Instance | BindingFlags.Public );
				method.Invoke( m_instance, new object[] { child, dropInfo, screenPoint } );
			}
		}

		public enum DockPosition
		{
			Left,
			Top,
			Right,
			Bottom
		}

		public static bool IsDocked( this EditorWindow wnd )
		{
	#if UNITY_2020_2_OR_NEWER
			return wnd.docked;
	#else
			var parent = new R_EditorWindow( wnd );
			return (bool)parent.Docked;
	#endif
		}

		public static void Undock( this EditorWindow wnd )
		{
			var parent = new R_EditorWindow( wnd );
			var dockArea = new R_DockArea( parent.Parent );
			dockArea.RemoveTab( wnd );
			wnd.Show( true );
		}

		public static void RemoveTab( this EditorWindow wnd )
		{
			var parent = new R_EditorWindow( wnd );
			var dockArea = new R_DockArea( parent.Parent );
			dockArea.RemoveTab( wnd );
		}

		/// <summary>
		/// Docks the second window to the first window at the given position
		/// </summary>
		public static void Dock( this EditorWindow wnd, EditorWindow other, DockPosition position )
		{
			var mousePosition = GetFakeMousePosition( wnd, position );

			var parent = new R_EditorWindow( wnd );
			var child = new R_EditorWindow( other );
			var dockArea = new R_DockArea( parent.Parent );
			var containerWindow = new R_ContainerWindow( dockArea.Window );
			var splitView = new R_SplitView( containerWindow.RootSplitView );
			var dropInfo = splitView.DragOver( other, mousePosition );
			dockArea.OriginalDragSource = child.Parent;
			splitView.PerformDrop( other, dropInfo, mousePosition );
		}


		/// <summary>
		/// Adds the the second window as a tab at the end of the first window tab list
		/// </summary>
		/// <param name="existingWindow"></param>
		/// <param name="newWindow"></param>
		public static void AddTab( this EditorWindow existingWindow, EditorWindow newWindow )
		{
			var parent = new R_EditorWindow( existingWindow );
			var child = new R_EditorWindow( newWindow );
			var dockArea = new R_DockArea( parent.Parent );
			dockArea.OriginalDragSource = child.Parent;
			dockArea.AddTab( newWindow );
		}

		private static Vector2 GetFakeMousePosition( EditorWindow wnd, DockPosition position )
		{
			Vector2 mousePosition = Vector2.zero;

			// The 20 is required to make the docking work.
			// Smaller values might not work when faking the mouse position.
			switch ( position )
			{
				case DockPosition.Left:
				mousePosition = new Vector2( 20, wnd.position.size.y / 2 );
				break;
				case DockPosition.Top:
				mousePosition = new Vector2( wnd.position.size.x / 2, 20 );
				break;
				case DockPosition.Right:
				mousePosition = new Vector2( wnd.position.size.x - 20, wnd.position.size.y / 2 );
				break;
				case DockPosition.Bottom:
				mousePosition = new Vector2( wnd.position.size.x / 2, wnd.position.size.y - 20 );
				break;
			}

			return GUIUtility.GUIToScreenPoint( mousePosition );
		}
	}
}
#endif