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

namespace NDesk.Options
{
	public class OptionValueCollection : IList, ICollection, IList<string>, ICollection<string>, IEnumerable<string>, IEnumerable
	{
		private List<string> values = new List<string>();

		private OptionContext c;

		bool ICollection.IsSynchronized
		{
			get
			{
				return ((ICollection)values).IsSynchronized;
			}
		}

		object ICollection.SyncRoot
		{
			get
			{
				return ((ICollection)values).SyncRoot;
			}
		}

		public int Count
		{
			get
			{
				return values.Count;
			}
		}

		public bool IsReadOnly
		{
			get
			{
				return false;
			}
		}

		bool IList.IsFixedSize
		{
			get
			{
				return false;
			}
		}

		object IList.this[int index]
		{
			get
			{
				return this[index];
			}
			set
			{
				((IList)values)[index] = value;
			}
		}

		public string this[int index]
		{
			get
			{
				AssertValid(index);
				if (index < values.Count)
				{
					return values[index];
				}
				return null;
			}
			set
			{
				values[index] = value;
			}
		}

		internal OptionValueCollection(OptionContext c)
		{
			this.c = c;
		}

		void ICollection.CopyTo(Array array, int index)
		{
			((ICollection)values).CopyTo(array, index);
		}

		public void Add(string item)
		{
			values.Add(item);
		}

		public void Clear()
		{
			values.Clear();
		}

		public bool Contains(string item)
		{
			return values.Contains(item);
		}

		public void CopyTo(string[] array, int arrayIndex)
		{
			values.CopyTo(array, arrayIndex);
		}

		public bool Remove(string item)
		{
			return values.Remove(item);
		}

		IEnumerator IEnumerable.GetEnumerator()
		{
			return values.GetEnumerator();
		}

		public IEnumerator<string> GetEnumerator()
		{
			return values.GetEnumerator();
		}

		int IList.Add(object value)
		{
			return ((IList)values).Add(value);
		}

		bool IList.Contains(object value)
		{
			return ((IList)values).Contains(value);
		}

		int IList.IndexOf(object value)
		{
			return ((IList)values).IndexOf(value);
		}

		void IList.Insert(int index, object value)
		{
			((IList)values).Insert(index, value);
		}

		void IList.Remove(object value)
		{
			((IList)values).Remove(value);
		}

		void IList.RemoveAt(int index)
		{
			((IList)values).RemoveAt(index);
		}

		public int IndexOf(string item)
		{
			return values.IndexOf(item);
		}

		public void Insert(int index, string item)
		{
			values.Insert(index, item);
		}

		public void RemoveAt(int index)
		{
			values.RemoveAt(index);
		}

		private void AssertValid(int index)
		{
			if (c.Option == null)
			{
				throw new InvalidOperationException("OptionContext.Option is null.");
			}
			if (index >= c.Option.MaxValueCount)
			{
				throw new ArgumentOutOfRangeException("index");
			}
			if (c.Option.OptionValueType == OptionValueType.Required && index >= values.Count)
			{
				throw new OptionException(string.Format(c.OptionSet.MessageLocalizer("Missing required value for option '{0}'."), c.OptionName), c.OptionName);
			}
		}

		public List<string> ToList()
		{
			return new List<string>(values);
		}

		public string[] ToArray()
		{
			return values.ToArray();
		}

		public override string ToString()
		{
			return string.Join(", ", values.ToArray());
		}
	}
}