'Taken from http://www.inttrust.ru/Site/itforum.nsf/0/0664'e64a23c83f40c325690c002582e1?OpenDocument
' 
' NotesUnreadMarks class (R1.1)
' Written by: Daniel Alvers (daniel.alvers@au.pwcglobal.com)
' PricewaterhouseCoopers (Aust)
' February, 7 2000
' 
' This code is provided as is and no warranty, express or implied, exists as to its fitness for use for any purpose.
' You are free to use and distributed the code as long as credit is retained and this header is not removed
'

Declare Function W32_SECKFMGetUserName Lib "nnotes.dll" Alias "SECKFMGetUserName" ( Byval UserName As String) As Integer
Declare Function W32_NSFDbOpen Lib "nnotes.dll" Alias "NSFDbOpen" ( Byval dbName As String, hDb As Long) As Integer
Declare Function W32_IDScan Lib "nnotes.dll" Alias "IDScan" ( Byval hUnreadTable As Integer, Byval First As Integer, NoteID As Long) As Integer
Declare Function W32_NSFDbGetUnreadNoteTable Lib "nnotes.dll" Alias "NSFDbGetUnreadNoteTable" (Byval hDb As Long, Byval UserName As String, Byval NameLength As Integer, Byval Create As Integer, hUnreadTable As Integer) As Integer
Declare Function W32_NSFDbUpdateUnread Lib "nnotes.dll" Alias "NSFDbUpdateUnread" ( Byval hDb As Long, Byval hTable As Integer) As Integer
Declare Function W32_NSFDbClose Lib "nnotes.dll" Alias "NSFDbClose" ( Byval hDb As Long) As Integer
Declare Function W32_IDDestroyTable Lib "nnotes.dll" Alias "IDDestroyTable" ( Byval hTable As Integer) As Integer
Declare Function W32_IDInsert Lib "nnotes.dll" Alias "IDInsert" ( Byval hTable As Integer, Byval NoteID As Long, retInserted As Integer) As Integer
Declare Function W32_IDDelete Lib "nnotes.dll" Alias "IDDelete" ( Byval hTable As Integer, Byval NoteID As Long, retDeleted As Integer) As Integer
Declare Function W32_IDIsPresent Lib "nnotes.dll" Alias "IDIsPresent" (Byval hTable As Integer, Byval NoteID As Long) As Integer
Declare Function W32_IDTableCopy Lib "nnotes.dll" Alias "IDTableCopy" ( Byval hOriginalTable As Integer, hNewCopy As Integer) As Integer
Declare Function W32_NSFDbSetUnreadNoteTable Lib "nnotes.dll" Alias "NSFDbSetUnreadNoteTable" ( Byval hDb As Long, Byval UserName As String, Byval NameLength As Integer, Byval Flush As Integer, Byval hOriginalTable As Integer, Byval hUnreadTable As Integer) As Integer

Type NoteIndex
	PrevNoteID As Long
	NoteID As Long
	NextNoteID As Long
End Type

Class NotesUnReadMarks
	
	Private DocList List As NoteIndex
	Private DocArray() As String
	Private NoteID As Long
	Private hUnreadTable As Integer
	Private hOriginalTable As Integer
	Private rc As Integer
	Private hDb As Long
	Private dbNotesDatabase As NotesDatabase
	Private sPrvServer As String
	Private sPrvFilePath As String
	Private sPrvDatabase As String
	Private sPrvUsername As String
	Private lPrvFirstNoteID As Long
	Private lPrvLastNoteID As Long
	Public UnreadNotes As NotesNoteCollection
	
	Sub Delete
		Call W32_IDDestroyTable(hUnreadTable)
		Call W32_NSFDbClose(hDb) 
	End Sub
	
	Sub New (inpNotesDatabase As NotesDatabase, inpUserName As String)
		
		Dim lCurrentNoteID As Long
		Dim iPrvScanFlag As Integer
		
		Set Me.dbNotesDatabase = New NotesDatabase(inpNotesDatabase.Server,inpNotesDatabase.FilePath)
		Me.sPrvServer = inpNotesDatabase.Server
		Me.sPrvFilePath = inpNotesDatabase.FilePath
		Me.sPrvUserName = inpUserName
		
		If Me.dbNotesDatabase Is Nothing Then
			Error 14005, "NotesUnreadMarks: Invalid database object."
		End If
		
		If Me.sPrvServer = "" Then
			sPrvDatabase = Me.sPrvFilePath
		Else
			sPrvDatabase = Me.sPrvServer + "!!" + Me.sPrvFilePath
		End If 
		
		'Open the target database
		Me.rc = W32_NSFDbOpen(sPrvDatabase, Me.hDb)
		If Me.rc <> 0 Then
			Error 14001, "NotesUnreadMarks: Unable to open database."
			End
		End If
		
		'Initialise IDTable variables
		Me.hUnreadTable = 0
		
		'Get the unread list
		Me.rc = W32_NSFDbGetUnreadNoteTable(Me.hDb, Me.sPrvUserName, Len(Me.sPrvUsername), True, Me.hUnreadTable)
		If Me.rc <> 0 Then
			Error 14002, "NotesUnreadMarks: Unable to get unread marks."
			End
		End If
		
		If Me.hUnreadTable = 0 Then
			Error 14003, "NotesUnreadMarks: Unread table is null."
			End
		End If
		
		'Refresh the Unread table
		Me.rc = W32_NSFDbUpdateUnread(Me.hDb, Me.hUnreadTable)
		If Me.rc <> 0 Then
			Error 14004, "NotesUnreadMarks: Error refreshing the unread note table."
			End
		End If
		
		Me.NoteID = 0
		lCurrentNoteID = 0
		iPrvScanFlag = True
		
		Set UnreadNotes = dbNotesDatabase.CreateNoteCollection(False)
		
		While (W32_IDScan(Me.hUnreadTable, iPrvScanFlag, Me.NoteID))
			If iPrvScanFlag Then
				lPrvFirstNoteID = Me.NoteID
				iPrvScanFlag = False
			End If
			
			If Not lCurrentNoteID = 0 Then
				Me.DocList(Hex(lCurrentNoteID)).NextNoteID = Me.NoteID 
				Me.DocList(Hex(Me.NoteID)).PrevNoteID = lCurrentNoteID
			End If
			
			Me.DocList(Hex(Me.NoteID)).NoteID = Me.NoteID
			UnreadNotes.Add(Me.NoteID)
			lCurrentNoteID = Me.NoteID
		Wend
		lPrvLastNoteID = lCurrentNoteID
	End Sub
	
	Public Function Server As String
		Server = Me.sPrvServer
	End Function
	
	Public Function FilePath As String
		FilePath = Me.sPrvFilePath
	End Function
	
	Public Function UserName As String
		UserName = Me.sPrvUserName
	End Function
	
	Public Function GetFirstDocument As Variant 
		Set GetFirstDocument = Me.dbNotesDatabase.GetDocumentByID(Hex(lPrvFirstNoteID))
	End Function
	
	Public Function GetLastDocument As Variant
		Set GetLastDocument = Me.dbNotesDatabase.GetDocumentByID(Hex(lPrvLastNoteID))
	End Function
	
	Public Function GetNextDocument(inpNotesDocument As NotesDocument) As Variant
		Dim IndexPoint As Long
		
		IndexPoint = DocList(inpNotesDocument.NoteID).NextNoteID
		
		If IndexPoint = 0 Then
			Erase DocList(inpNotesDocument.NoteID)
			Set GetNextDocument = Nothing
		Else
			Set GetNextDocument = Me.dbNotesDatabase.GetDocumentByID(Hex(IndexPoint))
		End If
	End Function
	
	Public Function GetPrevDocument(inpNotesDocument As NotesDocument) As Variant
		Dim IndexPoint As Long
		
		IndexPoint = DocList(inpNotesDocument.NoteID).PrevNoteID
		
		If IndexPoint = 0 Then
			Erase DocList(inpNotesDocument.NoteID)
			Set GetPrevDocument = Nothing
		Else
			Set GetPrevDocument = Me.dbNotesDatabase.GetDocumentByID(Hex(IndexPoint))
		End If
	End Function
	
	Function IsUnread(inpNotesDocument As NotesDocument) As Integer
		If DocList(inpNotesDocument.NoteID).NoteID = 0 Then
			Erase DocList(inpNotesDocument.NoteID)
			IsUnread = False
		Else
			IsUnread = True
		End If 
	End Function
	
	Sub MarkDocumentRead(inpNotesDocument As NotesDocument)
		
		Dim NoteID As Long
		NoteID = DocList(inpNotesDocument.NoteID).NoteID
		If NoteID = 0 Then
			Exit Sub
		End If
		
		'Copy the table so that changes can be merge to the original
		Me.rc = W32_IDTableCopy(Me.hUnreadTable, Me.hOriginalTable)
		If Me.rc <> 0 Then
			Error 14006, "NotesUnreadMarks: Unable to copy unread table."
			End
		End If
		
		'Refresh the Unread table
		Me.rc = W32_NSFDbUpdateUnread(Me.hDb, Me.hUnreadTable)
		If Me.rc <> 0 Then
			Error 14004, "NotesUnreadMarks: Error refreshing the unread note table."
			End
		End If
		
		If W32_IDIsPresent (Me.hUnReadTable, NoteID) Then
			Me.rc = W32_IDDelete (Me.hUnReadTable, NoteID, &h0)
			If Me.rc = 0 Then
				Me.rc = W32_NSFDbSetUnreadNoteTable(Me.hDb, Me.sPrvUserName, Len(Me.sPrvUsername), True, Me.hOriginalTable, Me.hUnreadTable)
				If Me.rc = 0 Then
					If DocList(inpNotesDocument.NoteID).NoteID = lPrvLastNoteID Then
						lPrvLastNoteID = DocList(inpNotesDocument.NoteID).PrevNoteID
					End If
					If DocList(inpNotesDocument.NoteID).NoteID = lPrvFirstNoteID Then
						lPrvFirstNoteID = DocList(inpNotesDocument.NoteID).NextNoteID
						DocList(lPrvFirstNoteID).PrevNoteID = 0
					End If
					Erase DocList(inpNotesDocument.NoteID)
				End If
			End If 
		End If 
		If Me.hOriginalTable <> 0 Then
			Call W32_IDDestroyTable(hOriginalTable)
		End If
	End Sub
	
	Sub MarkDocumentUnread(inpNotesDocument As NotesDocument)
		
		Dim NoteID As Long
		
		If inpNotesDocument Is Nothing Then Exit Sub 
		NoteID = Clng("&H" + inpNotesDocument.NoteID)
		
		'Copy the table so that changes can be merge to the original
		Me.rc = W32_IDTableCopy(Me.hUnreadTable, Me.hOriginalTable)
		If Me.rc <> 0 Then
			Error 14006, "NotesUnreadMarks: Unable to copy unread table."
			End
		End If
		
		'Refresh the Unread table
		Me.rc = W32_NSFDbUpdateUnread(Me.hDb, Me.hUnreadTable)
		If Me.rc <> 0 Then
			Error 14004, "NotesUnreadMarks: Error refreshing the unread note table."
			End
		End If
		
		Me.rc = W32_IDInsert (Me.hUnReadTable, NoteID, &h0)
		If Me.rc = 0 Then
			Me.rc = W32_NSFDbSetUnreadNoteTable(Me.hDb, Me.sPrvUserName, Len(Me.sPrvUsername), True, Me.hOriginalTable, Me.hUnreadTable)
			If Me.rc = 0 Then
				DocList(inpNotesDocument.NoteID).NoteID = NoteID
				DocList(Hex(lPrvLastNoteID)).NextNoteID = NoteID
				DocList(inpNotesDocument.NoteID).PrevNoteID = lPrvLastNoteID
				DocList(InpNotesDocument.NoteID).NextNoteID = 0
				lPrvLastNoteID = NoteID
			End If
		End If 
		
		If Me.hOriginalTable <> 0 Then
			Call W32_IDDestroyTable(hOriginalTable)
		End If
	End Sub
End Class