source: branches/PersistenceSpeedUp/HeuristicLab.ExtLibs/HeuristicLab.WinFormsUI/2.3.1/WinFormsUI-2.3.1/Docking/NestedPaneCollection.cs

using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Drawing;

namespace WeifenLuo.WinFormsUI.Docking {
  public sealed class NestedPaneCollection : ReadOnlyCollection<DockPane> {
    private INestedPanesContainer m_container;
    private VisibleNestedPaneCollection m_visibleNestedPanes;

    internal NestedPaneCollection(INestedPanesContainer container)
      : base(new List<DockPane>()) {
      m_container = container;
      m_visibleNestedPanes = new VisibleNestedPaneCollection(this);
    }

    public INestedPanesContainer Container {
      get { return m_container; }
    }

    public VisibleNestedPaneCollection VisibleNestedPanes {
      get { return m_visibleNestedPanes; }
    }

    public DockState DockState {
      get { return Container.DockState; }
    }

    public bool IsFloat {
      get { return DockState == DockState.Float; }
    }

    internal void Add(DockPane pane) {
      if (pane == null)
        return;

      NestedPaneCollection oldNestedPanes = (pane.NestedPanesContainer == null) ? null : pane.NestedPanesContainer.NestedPanes;
      if (oldNestedPanes != null)
        oldNestedPanes.InternalRemove(pane);
      Items.Add(pane);
      if (oldNestedPanes != null)
        oldNestedPanes.CheckFloatWindowDispose();
    }

    private void CheckFloatWindowDispose() {
      if (Count == 0 && Container.DockState == DockState.Float) {
        FloatWindow floatWindow = (FloatWindow)Container;
        if (!floatWindow.Disposing && !floatWindow.IsDisposed)
          NativeMethods.PostMessage(((FloatWindow)Container).Handle, FloatWindow.WM_CHECKDISPOSE, 0, 0);
      }
    }

    internal void Remove(DockPane pane) {
      InternalRemove(pane);
      CheckFloatWindowDispose();
    }

    private void InternalRemove(DockPane pane) {
      if (!Contains(pane))
        return;

      NestedDockingStatus statusPane = pane.NestedDockingStatus;
      DockPane lastNestedPane = null;
      for (int i = Count - 1; i > IndexOf(pane); i--) {
        if (this[i].NestedDockingStatus.PreviousPane == pane) {
          lastNestedPane = this[i];
          break;
        }
      }

      if (lastNestedPane != null) {
        int indexLastNestedPane = IndexOf(lastNestedPane);
        Items.Remove(lastNestedPane);
        Items[IndexOf(pane)] = lastNestedPane;
        NestedDockingStatus lastNestedDock = lastNestedPane.NestedDockingStatus;
        lastNestedDock.SetStatus(this, statusPane.PreviousPane, statusPane.Alignment, statusPane.Proportion);
        for (int i = indexLastNestedPane - 1; i > IndexOf(lastNestedPane); i--) {
          NestedDockingStatus status = this[i].NestedDockingStatus;
          if (status.PreviousPane == pane)
            status.SetStatus(this, lastNestedPane, status.Alignment, status.Proportion);
        }
      } else
        Items.Remove(pane);

      statusPane.SetStatus(null, null, DockAlignment.Left, 0.5);
      statusPane.SetDisplayingStatus(false, null, DockAlignment.Left, 0.5);
      statusPane.SetDisplayingBounds(Rectangle.Empty, Rectangle.Empty, Rectangle.Empty);
    }

    public DockPane GetDefaultPreviousPane(DockPane pane) {
      for (int i = Count - 1; i >= 0; i--)
        if (this[i] != pane)
          return this[i];

      return null;
    }
  }
}