/**
 * Namespace: System.Web.UI.WebControls
 * Class:     ListItemCollection
 *
 * Author:  Gaurav Vaish
 * Maintainer: gvaish@iitk.ac.in
 * Contact: <my_scripts2001@yahoo.com>, <gvaish@iitk.ac.in>
 * Implementation: yes
 * Status:  100%
 *
 * (C) Gaurav Vaish (2001)
 */

using System;
using System.Collections;
using System.Web;
using System.Web.UI;

namespace System.Web.UI.WebControls
{
	public class ListItemCollection : IList, ICollection, IEnumerable, IStateManager
	{
		private ArrayList items;
		private bool      saveAll;
		private bool      marked;
		
		public ListItemCollection()
		{
			items   = new ArrayList();
			saveAll = false;
			marked  = false;
		}
		
		public int Capacity
		{
			get
			{
				return items.Capacity;
			}
			set
			{
				items.Capacity = value;
			}
		}
		
		public int Count
		{
			get
			{
				return items.Count;
			}
		}
		
		public bool IsReadOnly
		{
			get
			{
				return items.IsReadOnly;
			}
		}
		
		public bool IsSynchronized
		{
			get
			{
				return items.IsSynchronized;
			}
		}
		
		public ListItem this[int index]
		{
			get
			{
				if(index < 0 || index >= Count)
					return null;
				return (ListItem)(items[index]);
			}
			set
			{
				if(index >= 0 && index < Count)
					items[index] = value;
			}
		}
		
		public object SyncRoot
		{
			get
			{
				return this;
			}
		}
		
		public void Add(ListItem item)
		{
			items.Add(item);
			if(marked)
				item.Dirty = true;
		}

		public void Add(string item)
		{
			Add(new ListItem(item));
		}

		public void AddRange(ListItem[] items)
		{
			foreach(ListItem item in items)
			{
				if(item!=null)
					Add(item);
			}
		}
		
		public void Clear()
		{
			items.Clear();
			if(marked)
				saveAll = true;
		}
		
		public bool Contains(ListItem item)
		{
			return items.Contains(item);
		}
		
		public void CopyTo(Array array, int index)
		{
			items.CopyTo(array, index);
		}
		
		public ListItem FindByText(string text)
		{
			int i=-1;
			foreach(object current in items)
			{
				i++;
				if(((ListItem)current).Text == text)
					break;
			}
			return (i==-1 ? null : (ListItem)items[i]);
		}
		
		public ListItem FindByValue(string value)
		{
			foreach(ListItem current in items)
			{
				if(current.Value == value)
				{
					return current;
				}
			}
			return null;
		}
		
		internal int FindByValueInternal(string value)
		{
			int i = -1;
			foreach(ListItem current in items)
			{
				i++;
				if(current.Value == value)
				{
					return i;
				}
			}
			return -1;
		}
		
		public IEnumerator GetEnumerator()
		{
			return items.GetEnumerator();
		}
		
		public int IndexOf(ListItem item)
		{
			return items.IndexOf(item);
		}
		
		public void Insert(int index, ListItem item)
		{
			items.Insert(index, item);
			if(marked)
				saveAll = true;
		}
		
		public void Insert(int index, string item)
		{
			Insert(index, new ListItem(item));
		}
		
		public void RemoveAt(int index)
		{
			if(index < 0 || index >= items.Count)
				return;
			items.RemoveAt(index);
			if(marked)
				saveAll = true;
		}
		
		public void Remove(ListItem item)
		{
			RemoveAt(IndexOf(item));
		}
		
		public void Remove(string item)
		{
			RemoveAt(IndexOf(ListItem.FromString(item)));
		}
		
		internal object SaveViewState()
		{
			if(saveAll)
			{
				string[] keys = new string[Count];
				string[] vals = new string[Count];
				for(int i=0; i < Count; i++)
				{
					keys[i] = this[i].Text;
					vals[i] = this[i].Value;
				}
				return new Triplet(Count, keys, vals);
			}
			ArrayList indices = new ArrayList();
			ArrayList states = new ArrayList();
			object o;
			for(int i=0; i < Count; i++)
			{
				o = this[i].SaveViewState();
				if(o!=null)
				{
					indices.Add(i);
					states.Add(o);
				}
			}
			if(indices.Count > 0)
				return new Pair(indices, states);
			return null;
		}
		
		internal void LoadViewState(object savedState)
		{
			if(savedState!=null)
			{
				if(savedState is Pair)
				{
					ArrayList indices = (ArrayList)(((Pair)savedState).First);
					ArrayList states  = (ArrayList)(((Pair)savedState).Second);
					for(int i=0; i < indices.Count; i++)
					{
						if( (int)indices[i] < Count )
							this[i].LoadViewState(states[i]);
						else
						{
							ListItem temp = new ListItem();
							temp.LoadViewState(states[i]);
							Add(temp);
						}
					}
				}
				if(savedState is Triplet)
				{
					Triplet t = (Triplet)savedState;
					items = new ArrayList((int)t.First);
					saveAll = true;
					string[] text = (string[])t.Second;
					string[] vals = (string[])t.Third;
					for(int i=0; i < text.Length; i++)
						items.Add(new ListItem(text[i], vals[i]));
				}
			}
		}
		
		internal void TrackViewState()
		{
			marked = true;
			foreach(ListItem current in this)
				current.TrackViewState();
		}
		
		bool IList.IsFixedSize
		{
			get
			{
				return false;
			}
		}

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

		int IList.Add(object item)
		{
			int index = (item is ListItem ? items.Add((ListItem)item) : -1);
			if(index!=-1 && marked)
				((ListItem)item).Dirty = true;
			return index;
		}
		
		bool IList.Contains(object item)
		{
			if(item is ListItem)
				return Contains((ListItem)item);
			return false;
		}
		
		int IList.IndexOf(object item)
		{
			if(item is ListItem)
				return IndexOf((ListItem)item);
			return -1;
		}
		
		void IList.Insert(int index, object item)
		{
			if(item is ListItem)
				Insert(index, (ListItem)item);
		}
		
		void IList.Remove(object item)
		{
			if(item is string)
				Remove((string)item);
			if(item is ListItem)
				Remove((ListItem)item);
		}
		
		bool IStateManager.IsTrackingViewState
		{
			get
			{
				return marked;
			}
		}
		
		void IStateManager.LoadViewState(object state)
		{
			LoadViewState(state);
		}
		
		object IStateManager.SaveViewState()
		{
			return SaveViewState();
		}
		
		void IStateManager.TrackViewState()
		{
			TrackViewState();
		}
	}
}