using System;
using System.Collections.Generic;
using System.Text;

namespace BitStrap
{
	public static class DictionaryExtensions
	{
		public struct GCFreeEnumerator<K, V>
		{
			private Dictionary<K, V>.Enumerator enumerator;

			public KeyValuePair<K, V> Current
			{
				get
				{
					return enumerator.Current;
				}
			}

			public GCFreeEnumerator(Dictionary<K, V> collection)
			{
				enumerator = collection.GetEnumerator();
			}

			public GCFreeEnumerator<K, V> GetEnumerator()
			{
				return this;
			}

			public bool MoveNext()
			{
				return enumerator.MoveNext();
			}
		}

		public static GCFreeEnumerator<K, V> Each<K, V>(this Dictionary<K, V> collection)
		{
			return new GCFreeEnumerator<K, V>(collection);
		}

		public static int Count<K, V>(this Dictionary<K, V> collection, Predicate<KeyValuePair<K, V>> predicate)
		{
			if (predicate == null)
			{
				return 0;
			}
			int num = 0;
			Dictionary<K, V>.Enumerator enumerator = collection.GetEnumerator();
			while (enumerator.MoveNext())
			{
				if (predicate(enumerator.Current))
				{
					num++;
				}
			}
			return num;
		}

		public static bool All<K, V>(this Dictionary<K, V> collection, Predicate<KeyValuePair<K, V>> predicate)
		{
			if (predicate == null)
			{
				return false;
			}
			Dictionary<K, V>.Enumerator enumerator = collection.GetEnumerator();
			while (enumerator.MoveNext())
			{
				if (!predicate(enumerator.Current))
				{
					return false;
				}
			}
			return true;
		}

		public static bool Any<K, V>(this Dictionary<K, V> collection, Predicate<KeyValuePair<K, V>> predicate)
		{
			if (predicate == null)
			{
				return false;
			}
			Dictionary<K, V>.Enumerator enumerator = collection.GetEnumerator();
			while (enumerator.MoveNext())
			{
				if (predicate(enumerator.Current))
				{
					return true;
				}
			}
			return false;
		}

		public static KeyValuePair<K, V> FirstOrDefault<K, V>(this Dictionary<K, V> collection)
		{
			Dictionary<K, V>.Enumerator enumerator = collection.GetEnumerator();
			if (enumerator.MoveNext())
			{
				return enumerator.Current;
			}
			return default(KeyValuePair<K, V>);
		}

		public static KeyValuePair<K, V> FirstOrDefault<K, V>(this Dictionary<K, V> collection, Predicate<KeyValuePair<K, V>> predicate)
		{
			Dictionary<K, V>.Enumerator enumerator = collection.GetEnumerator();
			while (enumerator.MoveNext())
			{
				if (predicate(enumerator.Current))
				{
					return enumerator.Current;
				}
			}
			return default(KeyValuePair<K, V>);
		}

		public static string ToStringFull<K, V>(this Dictionary<K, V> collection)
		{
			if (collection == null)
			{
				return "null";
			}
			if (collection.Count <= 0)
			{
				return "{}";
			}
			StringBuilder stringBuilder = new StringBuilder();
			stringBuilder.Append("{ ");
			Dictionary<K, V>.Enumerator enumerator = collection.GetEnumerator();
			while (enumerator.MoveNext())
			{
				stringBuilder.Append(enumerator.Current.Key.ToString());
				stringBuilder.Append("=");
				stringBuilder.Append(enumerator.Current.Value.ToString());
				stringBuilder.Append(", ");
			}
			stringBuilder.Remove(stringBuilder.Length - 2, 2);
			stringBuilder.Append(" }");
			return stringBuilder.ToString();
		}
	}
}