Refactor Windream session initialization and login checks

Refactored Windream session management to use IsLoggedIn() for determining when to re-initialize the session, removing the previous 2-hour expiration logic. Improved IsLoggedIn() to handle null session objects safely. Also removed explicit Windream initialization from frmNIHauptseite.vb, centralizing session handling and improving robustness against session expiration and null references.

ToolCollection/ClassNIProfile.vb

@@ -14,7 +14,6 @@ Public Class ClassNIProfile
         xmlConfigFile = oConfigPath
         ClassNIProfile.LoadFromXmlFile()
         ' 3b. Windream initialisieren (Connection, Session, ... aufbauen)
-        _windream.Init()
     End Sub
     Public Shared Function IsXmlAccessable() As Boolean
         Dim xml As New Xml.XmlDocument

ToolCollection/ClassWindream_allgemein.vb

@@ -107,10 +107,8 @@ Public Class ClassWindream_allgemein
     ''' <returns>Liefert True wenn das Anmelden erfolgreich war, sonst False</returns>
     ''' <remarks></remarks>
     Public Function Init() As Boolean
-        Dim oHourDifference As Integer
-        oHourDifference = CInt(DateDiff(DateInterval.Hour, CURRENToWMSession_Created, Now))
 
-        If IsNothing(CURRENToWMSession) Or oHourDifference >= 2 Then
+        If IsNothing(CURRENToWMSession) OrElse Not IsLoggedIn() Then
             If WMLOGIN_DOMAIN <> String.Empty Then
                 GetWMSessionAsUser(WMLOGIN_DOMAIN, Me.GetCurrentServer, WMLOGIN_USER, WMLOGIN_PW)
             Else
@@ -123,7 +121,6 @@ Public Class ClassWindream_allgemein
             Return True
         End If
 
-
     End Function
     Private Function GetWMSession()
         Try
@@ -530,6 +527,9 @@ Public Class ClassWindream_allgemein
     ''' <remarks></remarks>
     Public Function IsLoggedIn() As Boolean
         Try
+            If IsNothing(Me.oWMSession) Then
+                Return False
+            End If
             Return Me.oWMSession.aLoggedin
         Catch ex As Exception
             clsHelper.Add_Application_log("Unexpected error in Windream.IsLoggedIn: " & ex.Message)

ToolCollection/frmNIHauptseite.vb

@@ -68,17 +68,9 @@ Public Class frmNIHauptseite
         _windreamNI = New ClassNIWindream(_MyLogger)
         database = New ClassNIDatenbankzugriff(_MyLogger)
 
-
         ' 3b. Windream initialisieren (Connection, Session, ... aufbauen)
-        If _windreamNI.Init() = False Then
-            _Logger.Warn("Die Windream-Klasse konnte nicht initialisiert werden. Windream-Client unvollständig gestartert.")
-            Exit Sub
-
-        End If
         'ClassMoveRenameLogger.Init("", "MoveRename_", True)
 
-
-
         AddHandler bwProfil.DoWork, AddressOf bwProfil_DoWork
         AddHandler bwProfil.RunWorkerCompleted, AddressOf bwProfil_RunWorkerCompleted
         AddHandler bwProfil.ProgressChanged, AddressOf bwProfil_ProgressChanged