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

using System.Drawing;
using System.Data;
using System.Text;
using System.Windows.Forms;
using System.Runtime.InteropServices;
using System.Text.RegularExpressions;
using VEPROMS.CSLA.Library;

namespace Volian.Controls.Library
{
	public delegate void StepRTBEvent(object sender, EventArgs args);
	public partial class StepRTB : RichTextBox , IStepRTB
	{
		#region Events
		public event StepRTBEvent RTBSelectionChanged;
		private void OnRTBSelectionChanged(object sender, EventArgs args)
		{
			if (RTBSelectionChanged != null) RTBSelectionChanged(sender, args);
		}
		public event StepRTBEvent LinkLocationsChanged;
		private void OnLinkLocationChanged(object sender, EventArgs args)
		{
			if (LinkLocationsChanged != null) LinkLocationsChanged(sender, args);
		}
		public event StepRTBEvent RTBRangeStatusChanged;
		private void OnRTBRangeStatusChanged(object sender, EventArgs args)
		{
			if (RTBRangeStatusChanged != null) RTBRangeStatusChanged(sender, args);
		}
		/// <summary>
		/// This event  is not raised during all the in-between changes for link deletions
		/// </summary>
		public event StepRTBEvent RTBTextChanged;
		private void OnRTBTextChanged(object sender, EventArgs args)
		{
			if (RTBTextChanged != null) RTBTextChanged(sender, args);
		}
		#endregion
		#region Properties and Variables
		// use newer rich text box....
		//[DllImport("kernel32.dll", CharSet = CharSet.Auto)]
		//static extern IntPtr LoadLibrary(string lpFileName);
		//protected override CreateParams CreateParams
		//{
		//    get
		//    {
		//        CreateParams prams = base.CreateParams;
		//        if (LoadLibrary("msftedit.dll") != IntPtr.Zero)
		//        {
		//            //prams.ExStyle |= 0x020; // transparent

		//            prams.ClassName = "RICHEDIT50W";
		//        }
		//        return prams;
		//    }
		//}
		private StepItem _MyStepItem;
		public StepItem MyStepItem
		{
			get { return _MyStepItem; }
			set { _MyStepItem = value; }
		}
		private bool _IsDirty = false;
		private bool _InitializingRTB;
		private IContainer _Container = null;
		private string _MyClassName=string.Empty;
		public string MyClassName
		{
			get { if (_MyClassName == string.Empty)_MyClassName = CreateParams.ClassName; return _MyClassName; }
			set { _MyClassName = value; }
		}
		private E_EditPrintMode _epMode = E_EditPrintMode.Edit;
		public E_EditPrintMode EpMode
		{
			get { return _epMode; }
			set { _epMode = value; }
		}
		private E_ViewMode _vwMode = E_ViewMode.Edit;
		public E_ViewMode VwMode
		{
			get { return _vwMode; }
			set { _vwMode = value; }
		}
		private VE_Font _MyStyleFont;
		public VE_Font MyStyleFont
		{
			get { return _origDisplayText.TextFont; }
		}
		private ItemInfo _MyItemInfo;
		public ItemInfo MyItemInfo
		{
			get { return _MyItemInfo; }
			set
			{
				_MyItemInfo = value;
				if (value != null)
				{
					_InitializingRTB = true;
					DisplayText vlntxt = new DisplayText(_MyItemInfo, EpMode, VwMode);
					_origDisplayText = vlntxt;
#if(DEBUG)
					// Use Times New Roman for Debugging
					Font = new Font("Times New Roman", 14, FontStyle.Regular);
					//Font = _origDisplayText.TextFont.WindowsFont;
#elif(RELEASE)
					Font = _origDisplayText.TextFont.WindowsFont; // font defined in plant's format
#else //DEMO
					// Comment this out for DEMO to customer
					// UN-Comment this for testing
					//Font = _origDisplayText.TextFont.WindowsFont; // font defined in plant's format
#endif
					
					Text = ""; // Initialize text before add text
					// IMPORTANT: SetLineSpacing must be set before Links, otherwise it
					// was confusing the 'handle' of the rtf box.
					RTBAPI.SetLineSpacing(this, RTBAPI.ParaSpacing.PFS_EXACT);
					AddRtfText(vlntxt);
					AddRtfStyles();
					ReadOnly = !(EpMode == E_EditPrintMode.Edit && VwMode == E_ViewMode.Edit);
					_InitializingRTB = false;
					_IsDirty = false;
					ClearUndo();
					_MyItemInfo.MyConfig.PropertyChanged += new PropertyChangedEventHandler(MyConfig_PropertyChanged);
				}
			}
		}
		private bool _ProcessKeystrokes = true;
		public bool ProcessKeystrokes
		{
			get { return _ProcessKeystrokes; }
			set { _ProcessKeystrokes = value; }
		}
		
		//public EnterKeyHandler EnterKeyPressed;
		//protected override bool ProcessCmdKey(ref Message msg, Keys keyData)
		//{
		//    const int WM_KEYDOWN = 0x100;
		//    const int WM_SYSKEYDOWN = 0x104;
		//    if ((msg.Msg == WM_KEYDOWN) || (msg.Msg == WM_SYSKEYDOWN))
		//    {
		//        switch (keyData)
		//        {
		//            case Keys.Control | Keys.V:
		//                // check for valid data to be inserted:
		//                return base.ProcessCmdKey(ref msg, keyData);
		//            default:
		//                return base.ProcessCmdKey(ref msg, keyData);
		//        }
		//    }
		//    return base.ProcessCmdKey(ref msg, keyData);
		//} 
		private Point ScrollPos
		{
			get { return RTBAPI.GetScrollLocation(this); }
			set { RTBAPI.SetScrollLocation(this, value); }
		}
		private Rectangle _ContentsRectangle;
		public Rectangle ContentsRectangle
		{
			get { return _ContentsRectangle; }
			set
			{
				_ContentsRectangle = value;
				AdjustSizeForContents();
			}
		}
		public Size ContentsSize
		{
			get { return _ContentsRectangle.Size; }
		}
		private Size _AdjustSize;  // if 0,0 puts text right next to bottom of box.
		public Size AdjustSize
		{
			get { return _AdjustSize; }
			set
			{
				_AdjustSize = value;
				AdjustSizeForContents();
			}
		}
		public System.Windows.Forms.AutoScaleMode AutoScaleMode;
		private DisplayText _origDisplayText;
		private RichTextBox _rtbTemp = new RichTextBox();
		private string _MyLinkText;
		public string MyLinkText
		{
			get { return _MyLinkText; }
			set 
			{
				if (value != _MyLinkText)
				{
					_MyLinkText = value;
					OnLinkChanged(this, new StepPanelLinkEventArgs(_MyStepItem, _MyLinkText));
				}
			}
		}
		#endregion
		#region Constructors
		/// <summary>
		///     vlnRichTextBox constructor:
		///			Creates a MyDisplayRTB with extra support for veproms editing/printing.
		///			Arguments are:
		///				string txtbxname - name to give box (is this needed)
		///				ItemInfo itm - Item for which box is created
		///				int x,y - starting position for box
		///				int iwid - width of box
		///				int tbindx - tab index
		///				E_EditPrintMode ep_mode - edit or print.
		///				E_ViewMode vw_mode - view or edit.
		/// </summary>	
		public StepRTB()
		{
			InitializeComponent();
			SetUp();
		}
		public StepRTB(IContainer container)
		{
			container.Add(this);
			InitializeComponent();
			_Container = container;
			SetUp();
		}
		protected override void OnMouseWheel(MouseEventArgs e)
		{
			_MyStepItem.MyStepPanel.MouseWheel(e);
			//base.OnMouseWheel(e);
		}
		private void SetUp()
		{
			BorderStyle = System.Windows.Forms.BorderStyle.None;
			this.DetectUrls = true;
			ContentsResized += new ContentsResizedEventHandler(StepRTB_ContentsResized);
			this.LinkClicked += new LinkClickedEventHandler(StepRTB_LinkClicked);
			this.Click +=new EventHandler(StepRTB_Click);
			this.KeyPress += new KeyPressEventHandler(StepRTB_KeyPress);
			this.KeyDown += new KeyEventHandler(StepRTB_KeyDown);
			this.KeyUp += new KeyEventHandler(StepRTB_KeyUp);
			this.TextChanged += new EventHandler(StepRTB_TextChanged);
			this.MouseUp += new MouseEventHandler(StepRTB_MouseUp);
			this.MouseDown += new MouseEventHandler(StepRTB_MouseDown);
			this.SelectionChanged +=new EventHandler(StepRTB_SelectionChanged);
		}

		void MyConfig_PropertyChanged(object sender, PropertyChangedEventArgs e)
		{
			SaveConfig();
		}
		private void StepRTB_Click(object sender, EventArgs e)
		{
			if (ReadOnly) return;
		}
		public bool inRoAdd = false;
		void StepRTB_SelectionChanged(object sender, EventArgs e)
		{
			if (_InitializingRTB) return;
			//DebugSelection("SelectionChanged Event ");
			if (SelectionStart == 40 && SelectionLength == 1) vlnStackTrace.ShowStack("SELECTIONCHANGED EVENT");
			HandleSelectionChange();
		}
		private bool _MouseDown = false;
		private void StepRTB_MouseDown(object sender, MouseEventArgs e)
		{
			_MouseDown = true;
		}
		void StepRTB_MouseUp(object sender, MouseEventArgs e)
		{
			_MouseDown = false;
			HandleSelectionChange();
		}
		#endregion
		#region ApplicationSupport
		public void ToggleViewEdit()
		{
			ItemInfo tmp = MyItemInfo;
			MyItemInfo = null;
			ReadOnly = !ReadOnly;
			EpMode = ReadOnly ? E_EditPrintMode.Print : E_EditPrintMode.Edit;
			VwMode = ReadOnly ? E_ViewMode.View : E_ViewMode.Edit;
			Clear();
			MyItemInfo = tmp;
		}
		public void InsertRO(string value, string link)
		{
			Console.WriteLine("Before Insert Called: {0}", Rtf);
			AddRtfLink(value, link);
		}
		public void InsertTran(string value, string link)
		{
			AddRtfLink(value, link);
		}
		public void InsertSymbol(string symbol)
		{
			AddSymbol(symbol);
		}
		public void SetSelectedCase(char type)
		{
			switch (type)
			{
				case 'l':
					SelectedText = SelectedText.ToLower();
					break;
				case 'U':
					SelectedText = SelectedText.ToUpper();
					break;
				case 'T':
					SelectedText = SelectedText.Substring(0, 1).ToUpper() + SelectedText.Substring(1, SelectedText.Length - 1).ToLower();
					break;
			}
		}
		#endregion
		#region SaveData
		public void SaveText()
		{
			if (ReadOnly) return;
			if (!_IsDirty) return;
			if (_IsDirty)
			{
				bool success = _origDisplayText.Save((RichTextBox)this);
				if (success)
				{
					FindAllLinks();
					_IsDirty = false;
					ClearUndo();
				}
			}
		}
		public void SaveConfig()
		{
			if (!_MyItemInfo.MyConfig.IsDirty) return;
			Item itm = _MyItemInfo.Get();
			itm.MyContent.Config = _MyItemInfo.MyConfig.ToString();
			itm.Save();
			_MyItemInfo.MyConfig.IsDirty = false;
		}
		#endregion
		#region AddRtfTextAndStyles
		private void AddRtfText(DisplayText myDisplayText)
		{
			AddFontTable();
			foreach (displayTextElement vte in myDisplayText.DisplayTextElementList)
			{
				if (vte.Type == E_TextElementType.Text)
					AddRtf(vte);
				else if (vte.Type == E_TextElementType.Symbol)
					AddSymbol(vte);
				else
					AddRtfLink((displayLinkElement)vte);
			}
			SelectedRtf = _SelectedRtfSB.ToString() + "}";
			FindAllLinks();
		}
		private StringBuilder _SelectedRtfSB = new StringBuilder();
		private void AddFontTable()
		{
			StringBuilder sbbeg = new StringBuilder();
			StringBuilder sbend = new StringBuilder();
			if (Font.Bold)
			{
				sbbeg.Append(@"\b");
				sbend.Append(@"\b0");
			}
			if (Font.Underline)
			{
				sbbeg.Append(@"\ul");
				sbend.Insert(0, @"\ulnone");
			}
			if (Font.Italic)
			{
				sbbeg.Append(@"\i");
				sbend.Insert(0, @"\i0");
			}
			_SelectedRtfSB.Append(@"{\rtf1\ansi\ansicpg1252\deff0\deflang1033{\fonttbl{\f0\fnil\fcharset2 " + this.Font.FontFamily.Name + @";}"); //}\f0\fs" + this.Font.SizeInPoints * 2 + @" " + myDisplayTextElement.Text + @"}}";
			_SelectedRtfSB.Append(@"{\f1\fnil\fcharset0 Arial Unicode MS;}}");
			_SelectedRtfSB.Append("\r\n");
			// use styles to construct rtf commands to insert into next line (where \b, etc is)
			_SelectedRtfSB.Append(@"\viewkind4\uc1\pard\sl-240\slmult0" + sbbeg.ToString() + @"\fs" + this.Font.SizeInPoints * 2 + @" "); // \f0\fs" + this.Font.SizeInPoints * 2 + @" " + myDisplayTextElement.Text + @"}";
		}
		private void AddRtf(displayTextElement myDisplayTextElement)
		{
			_SelectedRtfSB.Append(@"\f0 " + myDisplayTextElement.Text);
		}
		private void AddRtf(string str)
		{
			// Because we're inserting rtf with { }, the surrounding styles are not included.  Get the font
			// style of current position & use it after the insert to set the style.
			RTBAPI.E_FontStyle fs = RTBAPI.GetFontStyle(this);
			int positionStart = SelectionStart;
			SelectedRtf = @"{\rtf1{\fonttbl{\f0\fcharset2 " + this.Font.FontFamily.Name + @";}}\f0\fs" + this.Font.SizeInPoints * 2 + @" " + str + @"}}";
			// Note that SelectedRtf does not contain the inserted text after the previous line.  We need
			// to determine how long the inserted string is in order to set its style. SelectionStart contains
			// the location after the insertion.
			int positionAfter = SelectionStart;
			Select(positionStart, positionAfter - positionStart);
			RTBAPI.SetFontStyle(this, fs);
			Select(positionAfter, 0);
		}
		private void AddText(string str)
		{
			// See comments in AddRtf(string str) to explain the font style setting
			RTBAPI.E_FontStyle fs = RTBAPI.GetFontStyle(this);
			int positionStart = SelectionStart;
			SelectedText = str;
			int positionAfter = SelectionStart;
			Select(positionStart, positionAfter - positionStart);
			RTBAPI.SetFontStyle(this, fs);
			Select(positionAfter, 0);
		}
		private void AddSymbol(displayTextElement myDisplayTextElement)
		{
			_SelectedRtfSB.Append(@"\f1 " + myDisplayTextElement.Text);
		}
		private void AddSymbol(string str)
		{
			// See comments in AddRtf(string str) to explain the font style setting
			RTBAPI.E_FontStyle fs = RTBAPI.GetFontStyle(this);
			int position = SelectionStart;
			SelectedRtf = @"{\rtf1{\fonttbl{\f0\fcharset0 Arial Unicode MS;}}\f0\fs" + this.Font.SizeInPoints * 2 + @" " + str + @"}";
			Select(position, 1);
			RTBAPI.SetFontStyle(this, fs);
			Select(position + 1, 0);
		}
		private string GetAddSymbolText(string symtxt)
		{
			return (@"{\f0\fs" + this.Font.SizeInPoints * 2 + @" " + symtxt + @"}");
		}
		private void AddRtfLink(displayLinkElement myDisplayLinkElement)
		{
			if (CreateParams.ClassName == "RICHEDIT50W")

				AddLink50(myDisplayLinkElement.Text, myDisplayLinkElement.Link);
			else
			{
				_SelectedRtfSB.Append(@"\f0\fs20 ");
				_SelectedRtfSB.Append(myDisplayLinkElement.TextAndLink);
			}
		}
		public void AddRtfLink(string linkUrl, string linkValue)
		{
			if (CreateParams.ClassName == "RICHEDIT50W")

				AddLink50(linkUrl, linkValue);
			else
				AddLink20(linkUrl, linkValue);
		}
		private void AddLink20(string linkValue, string linkUrl)
		{
			this.DetectUrls = false;
			int position = SelectionStart; // before inserttran = this.TextLength;
			SelectionLength = 0;
			SelectedRtf = @"{\rtf1\ansi\v <START]\v0 " + linkValue + @"\v " + linkUrl + @"\v0 \v [END>\v0 }";
			this.SelectionLength = 0;
			this.SelectionStart = position;
			FindAllLinks();
		}
		private void AddLink50(string linkValue, string linkUrl)
		{
			this.DetectUrls = false;
			int position = SelectionStart; // before inserttran = this.TextLength;
			SelectionLength = 0;
			SelectedRtf = string.Format(@"{{\rtf\field{{\*\fldinst{{HYPERLINK ""www.volian.com #{0}"" }}}}{{\fldrslt{{\cf2\ul {1}}}}}}}", linkUrl, linkValue);
			this.SelectionStart = this.TextLength;
			this.SelectionLength = 0;
		}
		private void AddRtfStyles()
		{
			if ((_origDisplayText.TextFont.Style & E_Style.Bold) > 0)
			{
				this.SelectAll();
				RTBAPI.ToggleBold(true, this, RTBAPI.RTBSelection.SCF_SELECTION);
				this.Select(0, 0);
			}
			if ((_origDisplayText.TextFont.Style & E_Style.Underline) > 0)
				RTBAPI.ToggleUnderline(true, this, RTBAPI.RTBSelection.SCF_ALL);
			if ((_origDisplayText.TextFont.Style & E_Style.Italics) > 0)
				RTBAPI.ToggleItalic(true, this, RTBAPI.RTBSelection.SCF_ALL);
		}
		#endregion
		#region HeightSupport
		public event StepRTBEvent HeightChanged;
		private void OnHeightChanged(object sender, EventArgs args)
		{
			if (HeightChanged != null) HeightChanged(sender, args);
		}
		private void AdjustSizeForContents()
		{
			// The client size should match the new rectangle.
			// First, determine the offset
			Size offset = Size - ClientSize;
			this.Size = ContentsSize + offset + AdjustSize;
			OnHeightChanged(this, new EventArgs());
		}
		public int CalculateHeight()
		{
			if (this.CreateParams.ClassName == "RICHEDIT50W")
				return CalculateHeight50();
			else
				return CalculateHeight20();
		}
		private int CalculateHeight20()
		{
			Application.DoEvents();
			int yBottom = GetPositionFromCharIndex(TextLength).Y;
			int yTop = GetPositionFromCharIndex(0).Y;
			int heightFont = SelectionFont.Height;
			int borderSize = this.Height - this.ClientSize.Height;
			int heightNext = (yBottom - yTop) + heightFont + borderSize + 2;// 2 pixels - 1 at the top and 1 at the bottom
			if (heightNext != Height)
			{
				Height = heightNext;

				OnHeightChanged(this, new EventArgs());
				ScrollPos = new Point(0, 0); // Scroll to make sure that the first line is displayed as the first line
			}
			return heightNext;
		}
		private int CalculateHeight50()
		{
			Application.DoEvents();
			int heightFont = SelectionFont.Height;
			int borderSize = this.Height - this.ClientSize.Height;
			int heightNext = (1 + GetLineFromCharIndex(TextLength)) * heightFont + borderSize + 2;// 2 pixels - 1 at the top and 1 at the bottom
			return heightNext;
		}
		#endregion
		#region ColorSupport - Not currently used.
		private void SetBackGroundColor(ItemInfo itemInfo)
		{
			string backcolor = null;
			int type = (int)itemInfo.MyContent.Type;
			FormatInfo formatinfo = itemInfo.ActiveFormat;
			if (type == (int)E_FromType.Procedure)
				backcolor = formatinfo.PlantFormat.FormatData.ProcData.BackColor;
			else if (type == (int)E_FromType.Section)
				backcolor = formatinfo.PlantFormat.FormatData.SectData.BackColor;
			else
			{
				int typindx = (int)itemInfo.MyContent.Type - 20000;  // what to do for other types rather than steps
				backcolor = formatinfo.PlantFormat.FormatData.StepDataList[typindx].StepLayoutData.BackColor;
			}
			BackColor = Color.FromName(backcolor);
		}
		#endregion
		#region EventSupport
		#region LinkEvents
		private StepPanelLinkEventArgs _MyLinkClickedEventArgs;
		public event StepRTBLinkEvent LinkChanged;
		private void OnLinkChanged(object sender, StepPanelLinkEventArgs args)
		{
			_MyLinkClickedEventArgs = args;
			if (LinkChanged != null) LinkChanged(sender, args);
		}
		public event StepRTBLinkEvent LinkGoTo;
		private void OnLinkGoTo(object sender, StepPanelLinkEventArgs args)
		{
			_MyLinkClickedEventArgs = args;
			if (LinkGoTo != null) LinkGoTo(sender, args);
		}
		public event StepRTBLinkEvent LinkModifyTran;
		private void OnLinkModifyTran(object sender, StepPanelLinkEventArgs args)
		{
			_MyLinkClickedEventArgs = args;
			if (LinkModifyTran != null) LinkModifyTran(sender, args);
		}
		public event StepRTBLinkEvent LinkModifyRO;
		private void OnLinkModifyRO(object sender, StepPanelLinkEventArgs args)
		{
			_MyLinkClickedEventArgs = args;
			if (LinkModifyRO != null) LinkModifyRO(sender, args);
		}
		private Point _savcurpos;
		private void StepRTB_LinkClicked(object sender,LinkClickedEventArgs args)
		{
			if (ReadOnly) return;

			_MyLinkClickedEventArgs = new StepPanelLinkEventArgs(_MyStepItem, args.LinkText);
			_savcurpos = Cursor.Position;
			SelectLinkFromPoint();
			OnLinkChanged(sender, _MyLinkClickedEventArgs);
		}
		#endregion
		#region TextOrContents
		void StepRTB_TextChanged(object sender, EventArgs e)
		{
			_IsDirty = true;
			FindAllLinks();
		}
		void StepRTB_ContentsResized(object sender, ContentsResizedEventArgs e)
		{
			ContentsRectangle = e.NewRectangle;
		}
		#endregion
		#region Selection Handlers
		bool _AdjustingSelection = false;
		private bool _ProcessingDelete; 
		private void HandleSelectionChange()
		{
			bool startingValue = _AdjustingSelection;
			if (_IdentifyingLinks || _ProcessingDelete) return;
			if (ProcessKeystrokes)
			{
				if (!_MouseDown && !_AdjustingSelection)
				{
					if (_LinkLocations != null)
					{
						DebugPrint("HSC===================>Beginning: SelectionStart {0}, SelectionLength {1}", SelectionStart, SelectionLength);
						_AdjustingSelection = true;
						LinkLocation ll = FindLinkLocation();
						LinkLocation llend = null;
						if (SelectionLength != 0)
							llend = FindLinkLocation(SelectionStart + SelectionLength - 1);
						if (ll != null)
						{
							if (SelectionStart == ll.Start && SelectionLength == 0)
							{
								if (SelectionStart >= 7)
								{
									DebugPrint("HSC===================>ll Insert: Sel {0}, Length {1}, Link Start {2}, Link Length {3}", SelectionStart, SelectionLength, ll.Start, ll.Length);
									SelectionStart = ll.Start - 7;
								}
							}
							else if (SelectionStart + SelectionLength > ll.End) // Beyond the end of the starting link
							{
								int end = SelectionStart + SelectionLength;
								if (llend != null) end = llend.End; // If it extends into another link extend the end to the end of that link
								DebugPrint("HSC===================>ll After: Sel {0}, Length {1}, Link Start {2}, Link Length {3}", SelectionStart, SelectionLength, ll.Start, ll.Length);
								SetSelection(ll.Start, end - ll.Start);
							}
							else if (SelectionStart >= ll.Start || SelectionLength > 0)// Within the starting link
							{
								DebugPrint("HSC===================>ll: Sel {0}, Length {1}, Link Start {2}, Link Length {3}", SelectionStart, SelectionLength, ll.Start, ll.Length);
								SetSelection(ll);
							}
						}
						else if (llend != null)
						{
							DebugPrint("HSC===================>llend: Sel {0}, Length {1}, Link Start {2}, Link Length {3}", SelectionStart, SelectionLength, llend.Start, llend.Length);
							// Check to see if the beginning starts before the <START] token.  If it does, adjust the start
							int newStart = SelectionStart + (SelectedText.StartsWith("<START]") ? 7 : 0);
							SetSelection(newStart, llend.End - newStart);
						}
						else
						{
							if (SelectedText.EndsWith("<START]") && !SelectedText.EndsWith("[END><START]"))
							{
								DebugPrint("HSC===================>Removing ending <START] token");
								SelectionLength = SelectionLength - 7;
							}
							if (SelectedText.StartsWith("<START]"))
							{
								DebugPrint("HSC===================>Removing starting <START] token");
								SetSelection(SelectionStart + 7, SelectionLength - 7);
							}
						}
						_AdjustingSelection = false;
					}
				}
			}
			if (startingValue != _AdjustingSelection)
				DebugPrint("================> _AdjustingSelection problem");
			DebugPrint("RS------ SelectionChange > {0}", FindRangeStatus());
			OnRTBSelectionChanged(this, new EventArgs());
		}
		private bool _CheckSelection = false;
		#endregion
		#region Delete Handlers
		private void HandleDeleteKeyWithSelectedText(KeyEventArgs e, char keychar)
		{
			_ProcessingDelete = true;
			FindRangeStatus();
			//DebugPrint("RS---------------- Delete > {0}", _RTBRangeStatus);
			switch (_RTBRangeStatus)
			{
				case RangeStatus.NoContainedLinks:
				case RangeStatus.Before_After:
				case RangeStatus.Before_EndLink:
				case RangeStatus.Before_EndBox:
				default:
					DeleteCurrentSelection(keychar);
					e.SuppressKeyPress = true;
					break;
				case RangeStatus.Before_Between: //myRTB1.SelectedText.EndsWith(@"[END><START]")
					DeleteEndBetweenLinks(keychar);
					e.SuppressKeyPress = true;
					break;
				case RangeStatus.Between_EndBox:
				case RangeStatus.Between_EndLink:
				case RangeStatus.Between_After:
					DeleteStartBetweenLinks(keychar);
					e.SuppressKeyPress = true;
					break;
				case RangeStatus.Between_Between:
					DeleteBetweenBetweenLinks(keychar);
					e.SuppressKeyPress = true;
					break;
				case RangeStatus.StartLink_EndBox:
				case RangeStatus.StartLink_EndLink:
				case RangeStatus.StartLink_After:
					ExpandSelectionToIncludeStart();
					DeleteCurrentSelection(keychar);
					e.SuppressKeyPress = true;
					break;
				case RangeStatus.StartLink_Between:
					ExpandSelectionToIncludeStart();
					DeleteEndBetweenLinks(keychar);
					e.SuppressKeyPress = true;
					break;
				case RangeStatus.StartBox_EndLink:
				case RangeStatus.StartBox_EndBox:
				case RangeStatus.StartBox_After:
					DeleteFromStartOfBox(keychar);
					e.SuppressKeyPress = true;
					break;
				case RangeStatus.StartBox_Between:
					DeleteFromStartOfBoxEndBetweenLinks(keychar);
					e.SuppressKeyPress = true;
					break;
				// REMOVE THESE CASES OR PUT A MESSAGE OUT SAYING ERROR IN CODE - CASE
				// NOT HANDLED
				case RangeStatus.Before_StartLink:
				case RangeStatus.Between_StartLink:
				case RangeStatus.StartLink_StartLink:
				case RangeStatus.StartBox_StartLink:
					break;
			}
			_ProcessingDelete = false;
			StepRTB_TextChanged(this, new EventArgs());
		}
		private void InsertCharBetweenLinks(LinkLocation ll)
		{
			InsertCharBetweenLinks(ll, ' ', false);
		}
		private void InsertCharBetweenLinks(LinkLocation ll, char charToAdd)
		{
			InsertCharBetweenLinks(ll, charToAdd, true);
		}
		/// <summary>
		/// This inserts a space in between two links.  
		/// It actually inserts "\v0 {space}\v " between the END tag and the START tag
		/// </summary>
		/// <param name="ll"></param>
		/// <param name="charToAdd"></param>
		/// <param name="setSelect"></param>
		private void InsertCharBetweenLinks(LinkLocation ll, char charToAdd, bool setSelect)
		{
			//_InsertingSpaceBetweenLinks = true;
			DebugPrint("ICBLvvvvvvvvvvvvvvv>>>");
			Rtf = Rtf.Substring(0, ll.StartRtf) + @"\v0 " + charToAdd.ToString() + @"\v " + Rtf.Substring(ll.StartRtf);
			//_InsertingSpaceBetweenLinks = false;
			if (setSelect)
				SelectionStart = ll.Start - 6;   // account for <START] - 1 for the character typed
			DebugPrint("ICBL^^^^^^^^^^^^^^^>>>");
		}
		private void ExpandSelectionToIncludeStart()
		{
			//_AdjustingSelection = true;
			SetSelection(SelectionStart - 7, SelectionLength + 7);  // Expand selection to include start
			//_AdjustingSelection = false;
		}
		private void DeleteBetweenBetweenLinks(char keychar)
		{
			
			DebugSelection("DeleteBetweenBetweenLinks");
			int selStart = SelectionStart - 7;
			int selLength = SelectionLength + 2; // Include the two added spaces
			InsertCharBetweenLinks(_RangeEndLink.NextLink); // Add a space at the end link
			InsertCharBetweenLinks(_RangeStartLink); // Add a space a the start link
			SetSelection(selStart, selLength);// Select everything including the spaces
			DeleteCurrentSelection(keychar);// Delete Selection
		}
		/// <summary>
		/// This is added to handle a glitch in richtextbox.  Depending on
		/// which direction that selection is made (left -> right or right -> left)
		/// a replacement or delete may not work, you'll just get a 'beep'.
		/// This approach consistently works.
		/// </summary>
		private void DeleteCurrentSelection(char key)
		{
			DebugPrint("vvvvvvvvvvvvxxxxxxxxxxxx>");
			DebugSelection("Before X");
			SelectedText = key==0?"X":key.ToString();			// replace text with X
			DebugSelection("After X");
			DebugPrint("------------xxxxxxxxxxxx>");
			if (key == 0)
			{
				_SendBackSpace = true;
				RtbSendKeys("{BS}");				// remove X
				Application.DoEvents();
				DebugSelection("After BS");
			}
			DebugPrint("^^^^^^^^^^^^xxxxxxxxxxxx>");
		}
		private void DeleteSelection(int start, int length, char keychar)
		{
			SetSelection(start, length);
			DeleteCurrentSelection(keychar);
		}
		private void DeleteEndBetweenLinks(char keychar)
		{
			_ProcessingKeys++;
			DebugSelection("DeleteEndBetweenLinks");
			int sstart = SelectionStart;
			int slen = SelectionLength + 1 - 7;
			// This puts a space at the link that starts at the end of the selection
			InsertCharBetweenLinks(_RangeEndLink.NextLink);
			//_AdjustingSelection = true;
			DeleteSelection(sstart, slen, keychar);
			//_AdjustingSelection = false;
			_ProcessingKeys--;
		}
		private void DeleteStartBetweenLinks(char keychar)
		{
			_ProcessingKeys++;
			DebugSelection("DeleteStartBetweenLinks");
			int slen = SelectionLength + 8;
			int sstart = SelectionStart - 7;
			//LinkLocation ll = FindBetweenLinks(SelectionStart);
			InsertCharBetweenLinks(_RangeStartLink);
			DeleteSelection(sstart, slen, keychar);
			_ProcessingKeys--;
		}
		private void DeleteFromStartOfBox(char keychar)
		{
			_ProcessingKeys++;
			DebugSelection("DeleteFromStartOfBox");
			int slen = SelectionLength;
			SetSelection(0, 0);
			//RtbSendKeys(" ");		// open for space between links which separates END/START tokens
			SelectedText = " ";
			DeleteSelection(0, slen + 8, keychar);
			_ProcessingKeys--;
		}
		private void DeleteFromStartOfBoxEndBetweenLinks(char keychar)
		{
			_ProcessingKeys++;
			DebugSelection("DeleteFromStartOfBoxEndBetweenLinks");
			// This puts a space at the link that starts at the end of the selection
			int sLen = SelectionStart + SelectionLength - 7 + 2;// -7 for <START] + 2 for the spaces that are added
			//LinkLocation ll = FindBetweenLinks(SelectionStart + SelectionLength);
			InsertCharBetweenLinks(_RangeEndLink.NextLink);
			//RtbSendKeys("{RIGHT} ");	// open for space between links which separates END/START tokens
			//int sLen = myRTB1.SelectionStart;
			SetSelection(0, 0);
			//RtbSendKeys(" ");		// open for space between links which separates END/START tokens
			SelectedText = " "; // open for space between links which separates END/START tokens
			DeleteSelection(0, sLen, keychar);
			_ProcessingKeys--;
		}
		#endregion
		#region KeyboardHandling
		void StepRTB_KeyUp(object sender, KeyEventArgs e)
		{
			if (!e.Shift) return;
			switch (e.KeyCode)
			{
				// this was put here rather than in the KeyDown event like the others
				// so that processing of keystroke (StepRTB_KeyDown) would position selectionstart
				// and selectionlength
				case Keys.Down:
					int newend = FindEndDown();
					if (newend > 0) SetSelection(SelectionStart, newend - SelectionStart);
					break;
				default:
					break;
			}

		}
		private bool IsControlChar = false;
		private bool _SendBackSpace = false;
		void StepRTB_KeyDown(object sender, KeyEventArgs e)
		{
			if (e.Control)
			{
				IsControlChar = true;
				switch (e.KeyCode)
				{
					case Keys.V:
						string buff = Clipboard.GetText(TextDataFormat.UnicodeText);
						return;
					case Keys.Home:
						StepRTB_HomeEndPressed(e);
						e.Handled = true;
						break;
					case Keys.End:
						StepRTB_HomeEndPressed(e);
						e.Handled = true;
						break;
				}
			}
			switch (e.KeyCode)
			{
				case Keys.Left:
					if (e.Shift)
					{
						int newstart = FindStart();		// find start of link ending on.
						int len = SelectionLength + SelectionStart - newstart;
						SetSelection(newstart, len);
						e.Handled = true;
						return;
					}
					if (e.Control || SelectionStart == 0)
					{
						StepRTB_ArrowPressed(e.Control ? E_ArrowKeys.CtrlLeft : E_ArrowKeys.Left);
						e.Handled = true;
					}
					HandleSelectionChange();
					break;
				case Keys.Up:
					int ln = GetLineFromCharIndex(SelectionStart);
					if (e.Control || ln == 0)
					{
						StepRTB_ArrowPressed(e.Control ? E_ArrowKeys.CtrlUp : E_ArrowKeys.Up);
						e.Handled = true;
					}
					// if shift-up & at selection had a link, handle this as special case.
					if (e.Shift && SelectionLength>0)
					{
						RangeStatus rs = FindRangeStatus();
						if (rs != RangeStatus.NoContainedLinks)
						{
							int curend = SelectionStart + SelectionLength;
							SelectionLength = 0;
							RtbSendKeys("{Up}");
							Application.DoEvents();
							Select(SelectionStart, curend - SelectionStart);
							e.Handled = true;
						}
					}
					else
						HandleSelectionChange();
					break;
				case Keys.Right:
					// If at beginning of box that starts with a link, don't worry about shift or not,
					// because selection is first character or link without any other selection.  Don't 
					// need to write code to handle link at beginning of box in Shift Right code because
					// it's handled in HandleSelectionChange.
					if (e.Shift && ((SelectionStart > 0) || (SelectionStart==0 && _LinkLocations.Count>0 && _LinkLocations[0].Start!=7)))
					{
						int newlen = FindEnd();
						int len = SelectionLength + newlen;
						SetSelection(SelectionStart, len);
						e.Handled = true;
						return;
					}
					if (e.Control || SelectionStart == this.Text.Length)
					{
						StepRTB_ArrowPressed(e.Control ? E_ArrowKeys.CtrlRight : E_ArrowKeys.Right);
						e.Handled = true;
					}
					HandleSelectionChange();
					break;
				case Keys.Down:
					int l = GetLineFromCharIndex(SelectionStart);
					Point pos = new Point();
					pos.X = ClientRectangle.Width;
					pos.Y = ClientRectangle.Height;
					int lastIndex = this.GetCharIndexFromPosition(pos);
					int lastLine = this.GetLineFromCharIndex(lastIndex);
					if (e.Control || l == lastLine)
					{
						StepRTB_ArrowPressed(e.Control ? E_ArrowKeys.CtrlDown : E_ArrowKeys.Down);
						HandleSelectionChange();
						e.Handled = true;
						return;
					}
					if (!e.Shift)HandleSelectionChange();
					// if shift-down & on link at beginning of box - do special processing (regular processing
					// didn't handle it correctly.
					if (e.Shift && lastLine > 0 && SelectionStart==0 && _LinkLocations.Count>0 && _LinkLocations[0].Start==7)
					{
						Point cpos = GetPositionFromCharIndex(SelectionStart);
						int addon = ClientRectangle.Height / (lastLine + 1);
						cpos.Y = cpos.Y + addon;
						int selend = GetCharIndexFromPosition(cpos);
						Select(7, selend-7);
						e.Handled = true;
					}
					break;
				case Keys.PageUp:
					StepRTB_PageKeyPressed(e);
					e.Handled = true;
					break;
				case Keys.PageDown:
					StepRTB_PageKeyPressed(e);
					e.Handled = true;
					break;
				case Keys.Delete:
					if (SelectionLength == 0)
					{
						foreach (LinkLocation lls in _LinkLocations)
						{
							if (SelectionStart >= lls.Start - 7 && SelectionStart < lls.End)
							{
								SetSelection(lls);// Select the link to the right
								HandleDeleteKeyWithSelectedText(e, '\x0');
								e.SuppressKeyPress = true;
								return;
							}
						}
						if (SelectionStart != TextLength)
						{
							SelectionStart++;// A Delete can be accomplished with a right arrow followed by a backspace.
							RtbSendKeys("{BS}"); // This is done due to a glitch in the RichTextBox that sometimes causes a beep rather than a delete
							e.SuppressKeyPress = true;
						}
					}
					else
						HandleDeleteKeyWithSelectedText(e, '\x0');
					break;
				case Keys.Back:
					if (_SendBackSpace)
					{
						_SendBackSpace = false;
						return;
					}
					_CheckSelection = true;
					if (SelectionLength == 0)
					{
						foreach (LinkLocation lls in _LinkLocations)
						{
							if (SelectionStart > lls.Start - 7 && SelectionStart <= lls.End)
							{
								SetSelection(lls);
								break;
							}
						}
					}
					if (SelectionLength > 0) HandleDeleteKeyWithSelectedText(e, '\x0');
					break;
			}
		}
		private void StepRTB_HomeEndPressed(KeyEventArgs keyargs)
		{
			if (MyItemInfo.IsProcedure || MyItemInfo.IsSection) return;
			// Cursor moves out of box only if control is pressed too - otherwise key is
			// handled in rtb.
			if (keyargs.Control)_MyStepItem.MyStepPanel.StepCursorKeys(this, keyargs);
		}
		private void StepRTB_PageKeyPressed(KeyEventArgs keyargs)
		{
			if (MyItemInfo.IsProcedure || MyItemInfo.IsSection) return;
			_MyStepItem.MyStepPanel.StepCursorKeys(this, keyargs);
		}
		private void StepRTB_ArrowPressed(E_ArrowKeys key)
		{
			Point cp = PointToClient(Cursor.Position);
			_MyStepItem.MyStepPanel.CursorMovement(this, cp, key);
		}
		private void StepRTB_KeyPress(object sender, System.Windows.Forms.KeyPressEventArgs e)
		{
			if (!ReadOnly)
			{
				// add the character with its font depending on the char....
				if (!IsControlChar)
				{
					bool done = false;
					string strpressed = null;
					if (e.KeyChar == '-')
						strpressed = GetAddSymbolText(@"\u8209?");
					else if (e.KeyChar == '{')
						strpressed = "\\{";
					else if (e.KeyChar == '}')
						strpressed = "\\}";
					else
						strpressed = e.KeyChar.ToString();
					if (e.KeyChar >= ' ')
					{
						LinkLocation ll = FindBetweenLinks();
						if (ll != null && SelectionLength == 0) // SelectionLength = 0 means insert
						{
							InsertCharBetweenLinks(ll, e.KeyChar);
							e.Handled = true;
						}
						else if (SelectionLength != 0)
						{
							HandleDeleteKeyWithSelectedText(new KeyEventArgs(Keys.None), e.KeyChar);
							e.Handled = true;
						}
					}
					if (!done)
					{
						if (e.KeyChar == '-')
							AddSymbol(@"\u8209?");
						else if (e.KeyChar == '{')
							AddRtf(@"\{");
						else if (e.KeyChar == '}')
							AddRtf(@"\}");
						else
							return;
						e.Handled = true; // flag that it's been handled, otherwise, will get 2 chars.
					}
				}
				IsControlChar = false;
			}
		}
		private void RtbSendKeys(string keys)
		{
			Focus();
			SendKeys.Send(keys);  // With .Net Framework 3.0 this can be replaced with EditingCommands
			// http://msdn.microsoft.com/en-us/library/ms771634.aspx
		}

		private void DoDeleteEndBetweenLinks()
		{
			DebugSelection("Beginning");
			int sstart = SelectionStart;
			RtbSendKeys("{RIGHT} ");		// open for space between links which separates END/START tokens
			SetSelection(sstart, SelectionStart - sstart - 1);  // 1 is accounting for typed space
			DebugSelection("SetSelection");
			RtbSendKeys("{DELETE}");		// deletes text including link
			RtbSendKeys("{RIGHT}{BS}");		// deletes space that was added
		}
		private void DoDeleteStartBetweenLinks()
		{
			int slen = SelectionLength;
			RtbSendKeys("{LEFT} ");
			SetSelection(SelectionStart, slen + 7);
			RtbSendKeys("{DELETE}");
			RtbSendKeys("{BS}");
		}
		#endregion
		#region LinkSelectionAndHandling
		private void SelectLinkFromPoint()
		{
			Point cp = PointToClient(_savcurpos);
			int index = GetCharIndexFromPosition(cp);
			SelectLink(index, 0);
		}
		private void SelectLink(int index, int len)
		{
			FindLink(index, len);
			if (SelectedText.IndexOf(@"[END>") > 0) MyLinkText = SelectedText.Substring(0, SelectedText.IndexOf(@"[END>"));
			else MyLinkText = SelectedText;
		}
		public bool IsSelectionLinked(int index, int len)
		{
			if (_LinkLocations == null)return false;
			int sel = index;
			int selLength = len;
			foreach (LinkLocation ll in _LinkLocations)
			{
				if (sel >= ll.Start && sel < ll.Start + ll.Length + 7) return true;
			}
			return false;
		}
		private int FindLink(int startIndex, int len)
		{
			int sel = startIndex;
			int selLength = len;
			foreach (LinkLocation ll in _LinkLocations)
			{
				// add 7 to include the '<START]'
				if (sel >= ll.Start && sel <= ll.Start + ll.Length)
				{
					SetSelection(ll.Start, ll.Length);
					if (SelectionLength == 0)
					{
						// try adding 7 to locEnd
						SetSelection(ll.Start, ll.Length + 7);
					}
					Console.WriteLine(string.Format("\nFindLink Start = {0}, Length = {1}\n", SelectionStart, SelectionLength));
					return SelectionStart;
				}
			}
			return SelectionStart;
		}
		
		private void DeleteLink()
		{
			SelectedText = "";
			MyLinkText = null;
			FindAllLinks();
		}
		#endregion
		#endregion
		#region SelectionStack
		Stack<SelectionData> _SelectionStack = new Stack<SelectionData>();
		public void PushSelection()
		{
			_SelectionStack.Push(new SelectionData(this));
		}
		public void PopSelection()
		{
			SelectionData selection = _SelectionStack.Pop();
			Select(selection.SelectionStart, selection.SelectionLength);
		}
		public class SelectionData
		{
			int _SelectionStart;
			public int SelectionStart
			{
				get { return _SelectionStart; }
				set { _SelectionStart = value; }
			}
			int _SelectionLength;
			public int SelectionLength
			{
				get { return _SelectionLength; }
				set { _SelectionLength = value; }
			}
			public SelectionData(RichTextBox richTextBox)
			{
				_SelectionStart = richTextBox.SelectionStart;
				_SelectionLength = richTextBox.SelectionLength;
			}
		}
		#endregion
		#region Link Support
		int _ProcessingKeys = 0;

		List<LinkLocation> _LinkLocations;
		public List<LinkLocation> LinkLocations
		{
			get { return _LinkLocations; }
		}
		private int _FALLevel = 0;
		private bool _IdentifyingLinks = false;
		public void FindAllLinks()
		{
			if (_IdentifyingLinks || _ProcessingDelete) return;
			//DebugPrint("FAL{0}vvvvvvvvvvvvvvvvvvvvvvvvv>>", ++_FALLevel);
			_AdjustingSelection = true;
			PushSelection();
			FindLinks();
			IdentifyLinks();
			PopSelection();
			LinkLocation llx = FindLinkLocation();
			if (_CheckSelection)
			{
				if (llx != null) SetSelection(llx.End, 0);
				_CheckSelection = false;
			}
			_AdjustingSelection = false;
			if (!_ProcessingDelete)
				OnLinkLocationChanged(this, new EventArgs());
			//DebugPrint("FAL{0}^^^^^^^^^^^^^^^^^^^^^^^^^>>", _FALLevel--);

		}
		private void FindLinks()
		{
			string str = Text;
			_LinkLocations = new List<LinkLocation>();
			MatchCollection matches = Regex.Matches(str, "<START](.*?)[[]END>");
			MatchCollection matchesRtf = Regex.Matches(Rtf, "<START](.*?)[[]END>");
			LinkLocation thisLink = null;
			for (int i = 0; i < matches.Count; i++) //each (Match match in matches)
			{
				Match match = matches[i];
				Match matchrtf = matchesRtf[i];
				thisLink = new LinkLocation(match.Index + 7, // If the [END> is immediately followed by <START] include it
					match.Length - (((match.Index + match.Length + 7 <= str.Length) && (str.Substring(match.Index + match.Length, 7) == "<START]")) ? 0 : 7),
					match.Value, matchrtf.Index, matchrtf.Length, thisLink);
				_LinkLocations.Add(thisLink);
			}
		}
		private void IdentifyLinks()
		{
			_IdentifyingLinks = true;
			foreach (LinkLocation ll in _LinkLocations)
			{
				SetSelection(ll);   // subtract off start token!
				RTBAPI.CharFormatTwo charFormat = RTBAPI.GetCharFormat(this, RTBAPI.RTBSelection.SCF_SELECTION);
				// Protect the link text to avoid manual changes
				charFormat.dwMask = RTBAPI.CharFormatMasks.CFM_LINK; // |  RTBAPI.CharFormatMasks.CFM_PROTECTED;
				charFormat.dwEffects = RTBAPI.CharFormatEffects.CFE_LINK; // |  RTBAPI.CharFormatEffects.CFE_PROTECTED;
				RTBAPI.SetCharFormat(this, RTBAPI.RTBSelection.SCF_SELECTION, charFormat);
			}
			_IdentifyingLinks = false;
		}
		private LinkLocation FindBetweenLinks()
		{
			return FindBetweenLinks(SelectionStart);
		}
		private LinkLocation FindBetweenLinks(int start)
		{
			DebugPrint("FL----------------Between>");
			foreach (LinkLocation ll in _LinkLocations)
				if (ll.Start == start && ll.StartsBetween)
					return ll;
			return null;
		}
		private LinkLocation FindLinkSelected()
		{
			DebugPrint("FL----------------Selected>");
			if (_LinkLocations == null) return null;
			foreach (LinkLocation ll in _LinkLocations)
				if (ll.Start == SelectionStart && ll.Length == SelectionLength) return ll;
			return null;
		}
		private LinkLocation FindLinkLocation()
		{
			return FindLinkLocation(SelectionStart);
		}
		private LinkLocation FindLinkLocation(int sel)
		{
			DebugPrint("FL----------------Location>");
			if (_LinkLocations == null) return null;
			foreach (LinkLocation ll in _LinkLocations)
			{
				// Moving right:
				//  if less than, allows stopping between two links
				if (ll.Start < sel && ll.End > sel)
				{
					DebugPrint("Greater Than {0} {1} {2}", sel, ll.Start, ll.End);
					return ll;
				}
				//  if less than or equal, does not stop between two links
				if ((!ll.StartsBetween) && ll.Start <= sel && ll.End > sel)
				{
					DebugPrint("Greater Than or Equal {0} {1} {2}", sel, ll.Start, ll.End);
					return ll;
				}
			}
			return null;
		}
		private int FindStart()
		{
			foreach (LinkLocation ll in _LinkLocations)
			{
				if (SelectionStart == ll.End) return ll.Start;
				if (SelectionStart == ll.Start)
				{
					if (ll.Start == 7) return 7;
					return ll.Start - 8;
				}
			}
			if (SelectionStart > 0) return SelectionStart - 1;
			return 0;
		}
		private int FindEnd()
		{
			foreach (LinkLocation ll in _LinkLocations)
			{
				if (SelectionStart + SelectionLength + 7 == ll.Start) return ll.Length + 7;
				// this is for in-between links
				if (SelectionStart + SelectionLength == ll.Start) return ll.Length;		
			}
			if (SelectionStart + SelectionLength < TextLength) return 1;
			return 0;
		}
		private int FindEndDown()
		{
			foreach (LinkLocation ll in _LinkLocations)
			{
				if (SelectionStart + SelectionLength >= ll.Start && SelectionStart + SelectionLength <= ll.End) return ll.End;
			}
			return 0;
		}
		private int FindStartUp()
		{
			DebugPrint("FINDSTARTUP Start = {0}, Len = {1}", SelectionStart, SelectionLength);
			foreach (LinkLocation ll in _LinkLocations)
			{
				DebugPrint("FINDSTARTUP link start = {0}, link end = {1}", ll.Start, ll.End);
				if ((SelectionStart >= ll.Start) && (SelectionStart <= ll.End))
				{
					DebugPrint("FINDSTARTUP - in link start = {0}, end = {1}", ll.Start, ll.End);
					return ll.Start;
				}
			}
			DebugPrint("FINDSTARTUP - Not in link");
			return -1;
		}
		public void SetSelection(LinkLocation ll)
		{
			SetSelection(ll.Start, ll.Length);
		}
		public void SetSelection(int locStart, int locLength)
		{
			//Application.DoEvents();  // Not needed since SendKeys is always done last.
			if (_IdentifyingLinks)
				DebugPrint("SS------------------------> {0} {1}", locStart, locLength);
			else
				DebugPrint("SS========================> {0} {1}", locStart, locLength);
			Select(locStart, locLength);
		}
		#endregion
		#region FontAndStylesSupport
		private void ToggleFontStyle(FontStyle style, bool att_on)
		{
			int start = SelectionStart;
			int len = SelectionLength;
			System.Drawing.Font currentFont;
			FontStyle fs;
			for (int i = 0; i < len; ++i)
			{
				Select(start + i, 1);
				currentFont = SelectionFont;
				fs = currentFont.Style;
				//add or remove style
				if (!att_on)fs = fs | style;
				else fs = fs & ~style;
				
				SelectionFont = new Font(
					currentFont.FontFamily,
					currentFont.Size,
					fs
					);
			}
		}
		/// <summary>
		///     Returns a Font with:
		///     1) The font applying to the entire selection, if none is the default font. 
		///     2) The font size applying to the entire selection, if none is the size of the default font.
		///     3) A style containing the attributes that are common to the entire selection, default regular.
		/// </summary>		
		/// 
		public Font GetFontDetails()
		{
			//This method should handle cases that occur when multiple fonts/styles are selected

			int start = SelectionStart;
			int len = SelectionLength;
			int TempStart = 0;

			if (len <= 1)
			{
				// Return the selection or default font
				if (SelectionFont != null)
					return SelectionFont;
				else
					return Font;		// should be default from format.
			}

			// Step through the selected text one char at a time	
			// after setting defaults from first char
			_rtbTemp.Rtf = SelectedRtf;

			//Turn everything on so we can turn it off one by one
			FontStyle replystyle =
				FontStyle.Bold | FontStyle.Italic | FontStyle.Underline;

			// Set reply font, size and style to that of first char in selection.
			_rtbTemp.Select(TempStart, 1);
			string replyfont = _rtbTemp.SelectionFont.Name;
			float replyfontsize = _rtbTemp.SelectionFont.Size;
			replystyle = replystyle & _rtbTemp.SelectionFont.Style;

			// Search the rest of the selection
			for (int i = 1; i < len; ++i)
			{
				_rtbTemp.Select(TempStart + i, 1);

				// Check reply for different style
				replystyle = replystyle & _rtbTemp.SelectionFont.Style;

				// Check font
				if (replyfont != _rtbTemp.SelectionFont.FontFamily.Name)
					replyfont = "";

				// Check font size
				if (replyfontsize != _rtbTemp.SelectionFont.Size)
					replyfontsize = (float)0.0;
			}

			// Now set font and size if more than one font or font size was selected
			if (replyfont == "")
				replyfont = _rtbTemp.Font.FontFamily.Name;

			if (replyfontsize == 0.0)
				replyfontsize = _rtbTemp.Font.Size;

			// generate reply font
			Font reply
				= new Font(replyfont, replyfontsize, replystyle);

			return reply;
		}
		#endregion
		#region EnumsSelectionRange
		private enum StartStatus : int
		{
			Before = 100,
			Between = 200,
			StartLink = 300,
			StartBox = 400
		};
		private enum EndStatus : int
		{
			After = 1,
			Between = 2,
			EndLink = 3,
			EndBox = 4,
			StartLink = 5
		};
		public enum RangeStatus : int
		{
			NoContainedLinks = 0,
			Before_After = StartStatus.Before + EndStatus.After,
			Before_Between = StartStatus.Before + EndStatus.Between,
			Before_EndLink = StartStatus.Before + EndStatus.EndLink,
			Before_EndBox = StartStatus.Before + EndStatus.EndBox,
			Before_StartLink = StartStatus.Before + EndStatus.StartLink,
			Between_After = StartStatus.Between + EndStatus.After,
			Between_Between = StartStatus.Between + EndStatus.Between,
			Between_EndLink = StartStatus.Between + EndStatus.EndLink,
			Between_EndBox = StartStatus.Between + EndStatus.EndBox,
			Between_StartLink = StartStatus.Between + EndStatus.StartLink,
			StartLink_After = StartStatus.StartLink + EndStatus.After,
			StartLink_Between = StartStatus.StartLink + EndStatus.Between,
			StartLink_EndLink = StartStatus.StartLink + EndStatus.EndLink,
			StartLink_EndBox = StartStatus.StartLink + EndStatus.EndBox,
			StartLink_StartLink = StartStatus.StartLink + EndStatus.StartLink,
			StartBox_After = StartStatus.StartBox + EndStatus.After,
			StartBox_Between = StartStatus.StartBox + EndStatus.Between,
			StartBox_EndLink = StartStatus.StartBox + EndStatus.EndLink,
			StartBox_EndBox = StartStatus.StartBox + EndStatus.EndBox,
			StartBox_StartLink = StartStatus.StartBox + EndStatus.StartLink
		};
		private RangeStatus _RTBRangeStatus;
		public RangeStatus RTBRangeStatus
		{
			get { return _RTBRangeStatus; }
			set
			{
				_RTBRangeStatus = value;
				if (!_ProcessingDelete) OnRTBRangeStatusChanged(this, new EventArgs());
			}
		}
		private LinkLocation _RangeStartLink = null;
		private LinkLocation _RangeEndLink = null;
		private RangeStatus FindRangeStatus()
		{
			_RangeStartLink = null;
			_RangeEndLink = null;
			if (_LinkLocations == null || _LinkLocations.Count == 0)
			{
				return RTBRangeStatus = RangeStatus.NoContainedLinks;
			}
			LinkLocation foundLink = null;
			int start = SelectionStart;
			int end = start + SelectionLength;

			foreach (LinkLocation ll in _LinkLocations)
			{
				if (foundLink == null && ((ll.Start >= start && ll.Start < end) || (ll.End >= start && ll.End < end)))
					foundLink = ll;
				if (_RangeStartLink == null && start >= ll.Start - 7 && start < ll.End)
					_RangeStartLink = ll;
				if (_RangeEndLink == null && end >= ll.Start && end <= ll.End)
					_RangeEndLink = ll;
			}
			DebugPrint("SelectionStart {0}, SelectionEnd {1}, TextLength {2}",
			  SelectionStart, SelectionStart + SelectionLength,
			  TextLength);
			if (_RangeStartLink != null)
				_RangeStartLink.Show("startLink");
			if (_RangeEndLink != null)
				_RangeEndLink.Show("endLink");
			if (foundLink != null)
				foundLink.Show("foundLink");

			if (foundLink == null)
				return RTBRangeStatus = RangeStatus.NoContainedLinks;

			StartStatus myStartStatus = StartStatus.Before;
			EndStatus myEndStatus = EndStatus.After;
			if (_RangeStartLink != null)
			{
				if (_RangeStartLink.Start == 7)
					myStartStatus = StartStatus.StartBox;
				else if (_RangeStartLink.StartsBetween)
					myStartStatus = StartStatus.Between;
				else
					myStartStatus = StartStatus.StartLink;
			}
			if (_RangeEndLink != null)
			{
				if (_RangeEndLink.End == TextLength)
					myEndStatus = EndStatus.EndBox;
				else if (_RangeEndLink.NextStart == _RangeEndLink.End)
					myEndStatus = EndStatus.Between;
				else if (end == _RangeEndLink.Start)
					myEndStatus = EndStatus.StartLink; // Should not happen because of code in HandleSelectionChange
				else //if (end == endLink.End)
					myEndStatus = EndStatus.EndLink;
			}
			return RTBRangeStatus = (RangeStatus)((int)myStartStatus + (int)myEndStatus);
		}
		#endregion
		#region Debug
		private bool _ShowDebug = false;
		public bool ShowDebug
		{
			get { return _ShowDebug; }
			set { _ShowDebug = value; }
		}
		private void DebugPrint(string where, string format, params object[] myParams)
		{
			DebugPrint(where + string.Format(format, myParams));
		}
		private void DebugPrint(string format, params object[] myParams)
		{
			if (_ShowDebug)
				Console.WriteLine(format, myParams);
		}
		private void DebugSelection(string where)
		{
			DebugPrint(where, ": {0} {1} '{2}'", SelectionStart, SelectionLength, SelectedText);
		}
		#endregion
	}
	#region LinkLocation Class
	public class LinkLocation
	{
		private int _Start;
		public int Start
		{
			get { return _Start; }
			set { _Start = value; }
		}
		private int _Length;
		public int Length
		{
			get { return _Length; }
			set { _Length = value; }
		}
		public int End
		{
			get { return _Length + _Start; }
		}
		private int _StartRtf;
		public int StartRtf
		{
			get { return _StartRtf; }
			set { _StartRtf = value; }
		}
		private int _LengthRtf;
		public int LengthRtf
		{
			get { return _LengthRtf; }
			set { _LengthRtf = value; }
		}
		public int EndRtf
		{
			get { return _LengthRtf + _StartRtf; }
		}
		private string _Text;
		public string Text
		{
			get { return _Text; }
			set { _Text = value; }
		}
		private LinkLocation _PreviousLink = null;
		public LinkLocation PreviousLink
		{
			get { return _PreviousLink; }
			set
			{
				_PreviousLink = value;
				value.NextLink = this;
			}
		}
		private LinkLocation _NextLink = null;
		public LinkLocation NextLink
		{
			get { return _NextLink; }
			set { _NextLink = value; }
		}
		public int PreviousEnd
		{
			get { return PreviousLink == null ? -1 : PreviousLink.End; }
		}
		public bool StartsBetween
		{
			get { return PreviousEnd == Start; }
		}
		public int NextStart
		{
			get { return NextLink == null ? -1 : NextLink.Start; }
		}
		public bool EndsBetween
		{
			get { return NextStart == End; }
		}
		public LinkLocation(int start, int length, string text, int startRtf, int lengthRtf, LinkLocation previousLink)
		{
			_Start = start;
			_Length = length;
			_Text = text;
			_StartRtf = startRtf;
			_LengthRtf = lengthRtf;
			if (previousLink != null) PreviousLink = previousLink;
		}
		public override string ToString()
		{
			return (string.Format("{0}, {1}", Start, End));
		}
		public void Show(string str)
		{
			if (PreviousLink != null)
				Console.WriteLine("LinkLocation: {0}.PreviousLink {1}", str, PreviousLink);
			Console.WriteLine("LinkLocation: {0} {1}", str, this);
			if (NextLink != null)
				Console.WriteLine("LinkLocation: {0}.NextLink {1}", str, NextLink);
		}

	}
	#endregion
}