using System;


using System.Collections.Generic;
using System.Linq;
using System.Text;
//using OpenTK.Graphics.OpenGL;

using Cairo;

using winColors = System.Drawing.Color;
using System.Diagnostics;
using System.Xml.Serialization;
using OpenTK.Input;
using System.ComponentModel;
using System.Xml;
using System.IO;
using System.Collections;
using System.Threading;

namespace Crow
{
	[DefaultTemplate("#Crow.Templates.ComboBox.goml")]
	[DefaultOverlayTemplate("#Crow.Templates.ComboBoxOverlay.goml")]
	public class ComboBox : TemplatedContainer
    {		
		#region CTOR
		public ComboBox() : base(){	}	
		#endregion

		bool _isPopped;
		string caption;
		GraphicObject _overlay;
		Group _list;
		IList data;
		int _selectedIndex;
		object _selectedItem;
		string _itemTemplate;
		string _overlayTemplate;

		public event EventHandler Pop;
		public event EventHandler Unpop;
		public event EventHandler<SelectionChangeEventArgs> SelectedItemChanged;

		#region implemented abstract members of TemplatedControl
		protected override void loadTemplate (GraphicObject template)
		{
			base.loadTemplate (template);
			loadOverlayTemplate (null);
		}
		public override GraphicObject Content {
			get {
				throw new NotImplementedException ();
			}
			set {
				throw new NotImplementedException ();
			}
		}
		#endregion

		protected virtual void loadOverlayTemplate(GraphicObject overlayTemplate)
		{
			if (overlayTemplate == null) {
				DefaultOverlayTemplate dt = (DefaultOverlayTemplate)this.GetType ().GetCustomAttributes (typeof(DefaultOverlayTemplate), true).FirstOrDefault ();
				Overlay = Interface.Load (dt.Path);
				Overlay.ResolveBindings ();
			} else
				Overlay = overlayTemplate;
			_list = Overlay.FindByName ("List") as Group;
		}

		[XmlAttributeAttribute][DefaultValue("#Crow.Templates.ItemTemplate.goml")]
		public string ItemTemplate {
			get { return _itemTemplate; }
			set { 
				//TODO:reload list with new template?
				_itemTemplate = value; 
			}
		}
		[XmlAttributeAttribute][DefaultValue("#Crow.Templates.ComboBoxOverlay.goml")]
		public string OverlayTemplate {
			get { return _overlayTemplate; }
			set { 
				//TODO:reload list with new template?
				_overlayTemplate = value; 

				Overlay = Interface.Load (_overlayTemplate);
				Overlay.ResolveBindings ();
				_list = Overlay.FindByName ("List") as Group;
			}
		}
		[XmlAttributeAttribute][DefaultValue(-1)]
		public int SelectedIndex{
			get { return _selectedIndex; }
			set { 
				//store value event if data is null, because in xml parsing selindex is always
				//before data, so it's impossible without that trick to set a default index in goml
				_selectedIndex = value;	
	
				if (data == null)					
					return;
	
				if (_selectedIndex > data.Count - 1 || _selectedIndex < 0)
					throw new Exception ("Combobox SelectedIndex out of range");


				_selectedItem = data [_selectedIndex];
				NotifyValueChanged ("SelectedIndex", SelectedIndex);
				SelectedItemChanged.Raise (this, new SelectionChangeEventArgs(_selectedItem));

				if (SelectedItem == null)
					Caption = "";
				else
					Caption = _selectedItem.ToString ();
				}
		}
		public object SelectedItem{
			set {
				if (_selectedItem == value)
					return;

				_selectedItem = value;
				_selectedIndex = data.IndexOf (_selectedItem);
				NotifyValueChanged ("SelectedIndex", _selectedIndex);
				SelectedItemChanged.Raise (this, new SelectionChangeEventArgs(_selectedItem));

				if (SelectedItem == null)
					Caption = "";
				else
					Caption = _selectedItem.ToString ();
			}

			get { return _selectedItem; }
		}
		[XmlAttributeAttribute][DefaultValue(null)]
		public IList Data {
			get {
				return data;
			}
			set {				
				data = value;
				if (_list == null)
					return;

				foreach (GraphicObject c in _list.Children) {
					c.ClearBinding ();
				}
				_list.Children.Clear ();
				_list.registerForGraphicUpdate ();
				if (data == null)
					return;
				if (SelectedIndex < 0)
					return;

				//force raise of changes
				SelectedIndex = SelectedIndex;

				pendingChildrenAddition = new Queue<GraphicObject> ();
				threadedLoadingFinished = false;

				Thread t = new Thread (loadingThread);
				t.Start ();
				t.Join ();

			}
		}
		public override void UpdateLayout (LayoutingType layoutType)
		{
			CheckPendingChildrenAddition ();
			base.UpdateLayout (layoutType);
		}
		internal void CheckPendingChildrenAddition()
		{
			if (pendingChildrenAddition == null)
				return;
			lock (pendingChildrenAddition) {
				if (!threadedLoadingFinished && pendingChildrenAddition.Count < 50)
					return;
				while (pendingChildrenAddition.Count > 0) {
					_list.addChild (pendingChildrenAddition.Dequeue ());
				}
			}
		}

		volatile Queue<GraphicObject> pendingChildrenAddition;
		volatile bool threadedLoadingFinished = false;

		void loadingThread()
		{
			#if DEBUG_LOAD_TIME
			Stopwatch loadingTime = new Stopwatch ();
			loadingTime.Start ();
			#endif

			MemoryStream ms = new MemoryStream ();
			lock (ItemTemplate) {
				using (Stream stream = Interface.GetStreamFromPath (ItemTemplate))
					stream.CopyTo (ms);
			}

			Type t = Interface.GetTopContainerOfGOMLStream (ms);

			foreach (var item in data) {
				ms.Seek(0,SeekOrigin.Begin);
				GraphicObject g = Interface.Load (ms, t);
				g.DataSource = item;
				g.MouseClick += itemClick;

				lock (pendingChildrenAddition) {
					pendingChildrenAddition.Enqueue (g);
				}
			}

			ms.Dispose ();			

			threadedLoadingFinished = true;

			#if DEBUG_LOAD_TIME
			loadingTime.Stop ();
			Debug.WriteLine("Listbox {2} Loading: {0} ticks \t, {1} ms",
			loadingTime.ElapsedTicks,
			loadingTime.ElapsedMilliseconds, this.ToString());
			#endif
		}
		public GraphicObject Overlay {
			get { return _overlay; }
			set { 
				if (_overlay != null) {
					_overlay.LayoutChanged -= _overlay_LayoutChanged;
					_overlay.MouseLeave -= _overlay_MouseLeave;
					_overlay.LogicalParent = null;
				}

				_overlay = value; 

				if (_overlay == null)
					return;

				_overlay.LogicalParent = this;
				_overlay.Focusable = true;
				_overlay.LayoutChanged += _overlay_LayoutChanged;
				_overlay.MouseLeave += _overlay_MouseLeave;
			}
		}
		[XmlAttributeAttribute()][DefaultValue("Combobox")]
		public string Caption {
			get { return caption; } 
			set {
				if (caption == value)
					return;
				caption = value; 
				NotifyValueChanged ("Caption", caption);
			}
		}        
		[XmlAttributeAttribute()][DefaultValue(false)]
		public bool IsPopped
		{
			get { return _isPopped; }
			set
			{
				_isPopped = value;

				if (_isPopped) {
					onPop (this, null);
					NotifyValueChanged ("SvgSub", "expanded");
					return;
				}

				onUnpop (this, null);
				NotifyValueChanged ("SvgSub", "collapsed");
			}
		}

		void itemClick(object sender, OpenTK.Input.MouseButtonEventArgs e){
			object datasource = (sender as GraphicObject).DataSource;
			SelectedItem = datasource;
			IsPopped = false;
			//Debug.WriteLine ((sender as GraphicObject).DataSource);
		}
		void _overlay_MouseLeave (object sender, MouseMoveEventArgs e)
		{
			IsPopped = false;
		}
		void _overlay_LayoutChanged (object sender, LayoutChangeEventArgs e)
		{
			ILayoutable tc = Overlay.Parent as ILayoutable;
			if (tc == null)
				return;
			Rectangle r = this.ScreenCoordinates (this.Slot);
			if (e.LayoutType == LayoutingType.Width) {
				if (Overlay.Slot.Width < tc.ClientRectangle.Width) {
					if (r.Left + Overlay.Slot.Width > tc.ClientRectangle.Right)
						Overlay.Left = tc.ClientRectangle.Right - Overlay.Slot.Width;
					else
						Overlay.Left = r.Left;
				}else
					Overlay.Left = 0;
			}else if (e.LayoutType == LayoutingType.Height) {
				if (Overlay.Slot.Height < tc.ClientRectangle.Height) {
					if (r.Bottom + Overlay.Slot.Height > tc.ClientRectangle.Bottom)
						Overlay.Top = r.Top - Overlay.Slot.Height;
					else
						Overlay.Top = r.Bottom;
				}else
					Overlay.Top = 0;
			}
		}

		[XmlAttributeAttribute()][DefaultValue(true)]//overiden to get default to true
		public override bool Focusable
		{
			get { return base.Focusable; }
			set { base.Focusable = value; }
		}

			
		public virtual void onPop(object sender, EventArgs e)
		{
			IGOLibHost tc = HostContainer;
			if (tc == null)
				return;
			if (Overlay != null) {
				Overlay.Visible = true;
				if (Overlay.Parent == null)
					tc.AddWidget (Overlay);
				(tc as OpenTKGameWindow).PutOnTop (Overlay);
			}
			Pop.Raise (this, e);
		}
		public virtual void onUnpop(object sender, EventArgs e)
		{
			IGOLibHost tc = HostContainer;
			if (tc == null)
				return;
			Overlay.Visible = false;
			Unpop.Raise (this, e);
		}
			
		public override void onMouseClick (object sender, MouseButtonEventArgs e)
		{
			IsPopped = !IsPopped;
			base.onMouseClick (sender, e);
		}

		public override void ClearBinding ()
		{
			//ensure popped window is cleared
			if (Overlay != null) {
				if (Overlay.Parent != null) {
					IGOLibHost tc = Overlay.Parent as IGOLibHost;
					if (tc != null)
						tc.DeleteWidget (Overlay);
				}
			}
			base.ClearBinding ();

		}
		public override void ResolveBindings ()
		{
			base.ResolveBindings ();
			if (Overlay != null)
				Overlay.ResolveBindings ();
		}
	}
}