/* Copyright 2007-2013 The NGenerics Team (https://github.com/ngenerics/ngenerics/wiki/Team) This program is licensed under the GNU Lesser General Public License (LGPL). You should have received a copy of the license along with the source code. If not, an online copy of the license can be found at http://www.gnu.org/copyleft/lesser.html. */ /* * The insertion and deletion code is based on the code found at http://eternallyconfuzzled.com/tuts/redblack.htm. * It's an excellent tutorial - if you want to understand Red Black trees, look there first. */ using System; using System.Collections.Generic; using System.Collections.ObjectModel; using System.Diagnostics.CodeAnalysis; using NGenerics.Comparers; using NGenerics.Patterns.Visitor; namespace NGenerics.DataStructures.Trees { ///

/// An implementation of a Red-Black tree. ///

/// The type of the keys in the . /// The type of the values in the . [SuppressMessage("Microsoft.Naming", "CA1710:IdentifiersShouldHaveCorrectSuffix")] #if (!SILVERLIGHT && !WINDOWSPHONE) //[Serializable] #endif public class RedBlackTree : RedBlackTree>, IDictionary // BinarySearchTreeBase { #region Construction /// public RedBlackTree() : base(new KeyValuePairComparer()) { // Do nothing - the default Comparer will be used by the base class. } /// public RedBlackTree(IComparer comparer) : base(new KeyValuePairComparer(comparer)) { // Do nothing else. } /// public RedBlackTree(Comparison comparison) : base(new KeyValuePairComparer(comparison)) { // Do nothing else. } #endregion #region Private Members private RedBlackTreeNode> FindNode(TKey key) { return base.FindNode(new KeyValuePair(key, default(TValue))) as RedBlackTreeNode>; } private bool Contains(KeyValuePair item, bool checkValue) { var node = FindNode(item); if ((node != null) && !checkValue) { return true; } return node != null && Equals(item.Value, node.Data.Value); } #endregion #region IDictionary Members ///

/// Removes the element with the specified key from the . ///

/// The key of the element to remove. /// /// true if the element is successfully removed; otherwise, false. This method also returns false if was not found in the original . /// /// /// is null. /// /// /// The is read-only. /// public bool Remove(TKey key) { return Remove(new KeyValuePair(key, default(TValue))); } ///

/// Adds an element with the provided key and value to the . ///

/// The object to use as the key of the element to add. /// The object to use as the value of the element to add. /// /// is null. /// /// /// An element with the same key already exists in the . /// /// /// The is read-only. /// public void Add(TKey key, TValue value) { if (Equals(key, null)) { throw new ArgumentNullException("key"); } Add(new KeyValuePair(key, value)); } ///

/// Determines whether the contains an element with the specified key. ///

/// The key to locate in the . /// /// true if the contains an element with the key; otherwise, false. /// /// /// is null. /// public bool ContainsKey(TKey key) { return Contains(new KeyValuePair(key, default(TValue)), false); } ///

/// Gets an containing the keys of the . ///

/// /// ///


		/// 	
		///


		public ICollection Keys
		{
			get
			{
				// Get the keys in sorted order
				var visitor = new KeyTrackingVisitor();
				var inOrderVisitor = new InOrderVisitor>(visitor);
				DepthFirstTraversal(inOrderVisitor);
				return new ReadOnlyCollection(visitor.TrackingList);
			}
		}

		
		/// 
		/// 
		/// 
		/// 
		/// 
		public bool TryGetValue(TKey key, out TValue value)
		{
			var node = FindNode(new KeyValuePair(key, default(TValue)));

			if (node == null)
			{
				value = default(TValue);
				return false;
			}
			
			value = node.Data.Value;
			return true;
		}

		/// 
		/// Gets an  containing the values in the .
		/// 
		/// 
		/// 
		/// 	
		/// 	
		/// 
		public ICollection Values
		{
			get
			{
				var visitor = new ValueTrackingVisitor();
				var inOrderVisitor = new InOrderVisitor>(visitor);

				DepthFirstTraversal(inOrderVisitor);

				return new ReadOnlyCollection(visitor.TrackingList);
			}
		}


		/// 
		/// Gets or sets the value with the specified key.
		/// 
		/// The key of the item to set or get.
		public TValue this[TKey key]
		{
			get
			{
				var node = FindNode(key);

				if (node == null)
				{
					throw new KeyNotFoundException("key");
				}

				return node.Data.Value;
			}
			set
			{
				var node = FindNode(key);

				if (node == null)
				{
					throw new KeyNotFoundException("key");
				}

				node.Data = new KeyValuePair(key, value);
			}
		}

		#endregion

		#region ICollection> Members
		
		/// 
		/// 
		/// 
		/// 
		/// 
		public override bool Contains(KeyValuePair item) {
			return Contains(item, true);
		}

		#endregion
	}
}