using System;

using System.Collections.Generic;

using System.Text;

using System.Collections.ObjectModel;

using System.ComponentModel;

using System.Windows.Forms;

namespace Aga.Controls.Tree

{

	internal class TreeColumnCollection : Collection<TreeColumn>

	{

		private TreeViewAdv _treeView;

		public TreeColumnCollection(TreeViewAdv treeView)

		{

			_treeView = treeView;

		}

		protected override void InsertItem(int index, TreeColumn item)

		{

			base.InsertItem(index, item);

			BindEvents(item);

			_treeView.UpdateColumns();

		}

		protected override void RemoveItem(int index)

		{

			UnbindEvents(this[index]);

			base.RemoveItem(index);

			_treeView.UpdateColumns();

		}

		protected override void SetItem(int index, TreeColumn item)

		{

			UnbindEvents(this[index]);

			base.SetItem(index, item);

			item.Owner = this;

			BindEvents(item);

			_treeView.UpdateColumns();

		}

		protected override void ClearItems()

		{

			foreach (TreeColumn c in Items)

				UnbindEvents(c);

			Items.Clear();

			_treeView.UpdateColumns();

		}

		private void BindEvents(TreeColumn item)

		{

			item.Owner = this;

			item.HeaderChanged += HeaderChanged;

			item.IsVisibleChanged += IsVisibleChanged;

			item.WidthChanged += WidthChanged;

			item.SortOrderChanged += SortOrderChanged;

		}

		private void UnbindEvents(TreeColumn item)

		{

			item.Owner = null;

			item.HeaderChanged -= HeaderChanged;

			item.IsVisibleChanged -= IsVisibleChanged;

			item.WidthChanged -= WidthChanged;

			item.SortOrderChanged -= SortOrderChanged;

		}

		void SortOrderChanged(object sender, EventArgs e)

		{

			TreeColumn changed = sender as TreeColumn;

			//Only one column at a time can have a sort property set

			if (changed.SortOrder != SortOrder.None)

			{

				foreach (TreeColumn col in this)

				{

					if (col != changed)

						col.SortOrder = SortOrder.None;

				}

			}

			_treeView.UpdateHeaders();

		}

		void WidthChanged(object sender, EventArgs e)

		{

			_treeView.ChangeColumnWidth(sender as TreeColumn);

		}

		void IsVisibleChanged(object sender, EventArgs e)

		{

			_treeView.FullUpdate();

		}

		void HeaderChanged(object sender, EventArgs e)

		{

			_treeView.UpdateView();

		}

	}

}