'/********************************************************************/
'/* $RCSfile: CIHash.vb,v $ */
'/* $Date: 2006/12/27 16:12:01 $ */
'/* $Revision: 1.4 $ */
'/* $Author: mike $ */
'/********************************************************************/
'  Make a case insensitve Hashtable
Option Explicit On 
Option Strict On
Imports System
Imports System.Collections
Public Class CIHashtable
	Inherits Hashtable

	Dim m_aryKeysLC As ArrayList
	Dim m_aryKeys As ArrayList
	Dim m_bIsCaseSensitive As Boolean

	' --------------------------------------------------------------------
	Public Sub New()
		Me.New(False)
	End Sub
	Public Sub New(ByVal nCapacity As Integer)
		Me.New(nCapacity, False)
	End Sub
	Public Sub New(ByVal nCapacity As Integer, ByVal IsCaseSensitive As Boolean)
		MyBase.New(nCapacity)
		m_aryKeysLC = New ArrayList
		m_aryKeys = New ArrayList
		m_bIsCaseSensitive = IsCaseSensitive
	End Sub
	Public Sub New(ByVal IsCaseSensitive As Boolean)
		MyBase.New()
		m_aryKeysLC = New ArrayList
		m_aryKeys = New ArrayList
		m_bIsCaseSensitive = IsCaseSensitive
	End Sub
	Public Sub New(ByVal IsCaseSensitive As Boolean, ByVal d As IDictionary)
		MyBase.New(d)
		m_aryKeysLC = New ArrayList
		m_aryKeys = New ArrayList
		m_bIsCaseSensitive = IsCaseSensitive
	End Sub
	Public Sub New(ByVal d As IDictionary)
		Me.New(False, d)
	End Sub
	Public Sub New(ByVal ht As CIHashtable)
		MyBase.New(ht)
		m_aryKeysLC = New ArrayList
		m_aryKeys = New ArrayList

		Dim de As IDictionaryEnumerator = MyBase.GetEnumerator
		While de.MoveNext
			If Me.m_bIsCaseSensitive = False AndAlso de.Key.GetType Is GetType(System.String) Then
				Dim strKey As String = CStr(de.Key)
				m_aryKeysLC.Add(strKey.ToLower)
			Else
				m_aryKeysLC.Add(de.Key)
			End If
			m_aryKeys.Add(de.Key)
		End While
		m_bIsCaseSensitive = ht.IsCaseSensitive
	End Sub
	Public Sub New(ByVal ht As Hashtable)
		MyBase.New(ht)
		m_aryKeysLC = New ArrayList
		m_aryKeys = New ArrayList
		For Each dict As DictionaryEntry In ht
			If dict.Key.GetType Is GetType(System.String) Then
				m_aryKeysLC.Add(CStr(dict.Key).ToLower)
			Else
				m_aryKeysLC.Add(dict.Key)
			End If
			m_aryKeys.Add(dict.Key)
		Next
		m_bIsCaseSensitive = False
	End Sub

	Public ReadOnly Property IsCaseSensitive() As Boolean
		Get
			Return m_bIsCaseSensitive
		End Get
	End Property
	Private Function GetKeyOfs(ByVal key As Object) As Integer
		Try
			If Me.m_aryKeysLC.Count = 0 Then
				Throw New Exception("Key not found in collection. Collection is empty")
			End If
			If (Me.m_bIsCaseSensitive = False) AndAlso (key.GetType Is GetType(System.String)) Then
				Dim strKeyLC As String = CStr(key).ToLower
				For nCnt As Integer = 0 To Me.m_aryKeysLC.Count - 1
					If Me.m_aryKeysLC(nCnt).GetType Is GetType(System.String) Then
						If strKeyLC = CStr(m_aryKeysLC(nCnt)) Then
							Return nCnt
						End If
					End If
				Next
			Else
				Dim nCnt As Integer = 0

				Dim de As IDictionaryEnumerator = MyBase.GetEnumerator
				While de.MoveNext
					If Me.m_aryKeys(nCnt) Is key Then
						Return nCnt
					End If
					nCnt = nCnt + 1
				End While
			End If
		Catch ex As Exception
			CI.f_strErrMsg = ex.ToString
			Debug.Assert(False, ex.ToString)
		End Try
		Return -1
	End Function

	Default Public Overrides Property Item(ByVal key As Object) As Object
		Get
			If key Is Nothing Then
				Throw New Exception("Key is NULL. Key not not valid")
			End If
			If Me.m_aryKeysLC.Count = 0 Then
				Return Nothing
			End If
			Dim nCnt As Integer = GetKeyOfs(key)
			If nCnt >= 0 Then
				Return MyBase.Item(Me.m_aryKeys(nCnt))
			End If
			Return Nothing
		End Get
		Set(ByVal Value As Object)
			Static nItter As Integer
			nItter += 1
			If Me.m_aryKeysLC.Count = 0 Then
				Throw New Exception("Key not found in collection. Collection is empty")
			End If
			If key Is Nothing Then
				Throw New Exception("Key is NULL. Key not not valid")
			End If
			Try
				Dim nCnt As Integer = GetKeyOfs(key)
				MyBase.Item(Me.m_aryKeys(nCnt)) = Value
			Catch ex As Exception
				CI.f_strErrMsg = ex.ToString
				Debug.Assert(False, ex.ToString)
			End Try
			nItter -= 1
		End Set
	End Property

	Public Overloads Sub Remove(ByVal key As Object)
		Dim nCnt As Integer = GetKeyOfs(key)
		MyBase.Remove(m_aryKeys(nCnt))
		m_aryKeysLC.RemoveAt(nCnt)
		m_aryKeys.RemoveAt(nCnt)
	End Sub

	Public Shared Sub Swap(ByRef ht1 As CIHashtable, ByRef ht2 As CIHashtable)
		Dim htTmp As CIHashtable = New CIHashtable(ht1)
		ht1 = New CIHashtable(ht2)
		ht2 = New CIHashtable(htTmp)
	End Sub

	Public Overloads Shared Sub Overlay(ByRef htTarget As CIHashtable, ByRef htOverlay As CIHashtable)
		If htOverlay Is Nothing Then Return
		If htTarget Is Nothing Then
			htTarget = New CIHashtable(htOverlay)
			Return
		End If
		For Each d As DictionaryEntry In htOverlay
			If htTarget.ContainsKey(d.Key) Then
				htTarget(d.Key) = d.Value
			Else
				htTarget.Add(d.Key, d.Value)
			End If
		Next
	End Sub
	Public Overloads Sub Add(ByVal key As Object, ByVal value As Object)
		' If IsCaseSensitive = False, and key is string, and key exists: it is updated
		If (Me.m_bIsCaseSensitive = False) AndAlso (key.GetType Is GetType(System.String)) Then
			key = CStr(key).Trim
			If CStr(key) = "" Then
				Throw New Exception("Invalid Key. Key cannot be null string or only whitespace")
			End If
			Dim strKeyLC As String = CStr(key).ToLower
			If Not m_aryKeysLC.Contains(strKeyLC) Then
				m_aryKeysLC.Add(strKeyLC)
				m_aryKeys.Add(key)
				MyBase.Add(key, value)
			Else
				Dim nCnt As Integer = GetKeyOfs(key)
				MyBase.Item(Me.m_aryKeys(nCnt)) = value
			End If
		Else
			MyBase.Add(key, value)
			m_aryKeysLC.Add(key)
			m_aryKeys.Add(key)
		End If
	End Sub
	Public Overloads Sub Clear()
		MyBase.Clear()
		m_aryKeysLC.Clear()
		m_aryKeys.Clear()
	End Sub

	Public Overloads Function Contains(ByVal key As Object) As Boolean
		If (m_bIsCaseSensitive = False) AndAlso (key.GetType Is GetType(System.String)) Then
			key = CStr(key).Trim
			If CStr(key) = "" Then
				Throw New Exception("Invalid Key. Key cannot be null string or only whitespace")
			End If
			Return m_aryKeysLC.Contains(CStr(key).ToLower)
		Else
			Return MyBase.Contains(key)
		End If
	End Function

	Public Overloads Function ContainsKey(ByVal key As Object) As Boolean
		If (m_bIsCaseSensitive = False) AndAlso (key.GetType Is GetType(System.String)) Then
			key = CStr(key).Trim
			If CStr(key) = "" Then
				Throw New Exception("Invalid Key. Key cannot be null string or only whitespace")
			End If
			Return m_aryKeysLC.Contains(CStr(key).ToLower)
		Else
			Return MyBase.Contains(key)
		End If
	End Function

End Class ' CIHash