'----------------------------------------------------------------------------
'  EgalTech 2016-2016
'----------------------------------------------------------------------------
' File : AutomaticCloseExpander.vb       Data : 8.9.16        Versione : 1
' Content : AutomatiCloseExpander Behavior (see detailed description below)
'
' Created by : Emmanuele Sassi
' Edited by : 
'
' Changes : 
'
'----------------------------------------------------------------------------
'
' Behavior description: permit to close other Expander when one is about to expand if they have to use more space than how many the StackPanel offers.
' Control that can use this behavior: StackPanel
' Internal structure of the control that can use it (example):
'
'  <StackPanel>
'     <Expander Header="Expander"/>
'     <Expander Header="Expander"/>
'     <Button Height="30" Width="30"/>
'     <Expander Header="Expander">
'     </Expander>
'     <Interactivity:Interaction.Behaviors>
'        <local:AutomaticCloseExpander/>
'     </Interactivity:Interaction.Behaviors>
'  </StackPanel>
'
' IMPORTANT: The behavior have to be added at the end of the StackPanel to function correctly
' Needed library: System.Windows.Interactivity 

Imports System.Windows.Interactivity

Public Class AutomaticCloseExpander
   Inherits Behavior(Of StackPanel)

   Private ExpanderList As New List(Of Expander)
   Private OtherControlList As New List(Of FrameworkElement)

   Protected Overrides Sub OnAttached()
      MyBase.OnAttached()
      For Each StackPanelChildren In Me.AssociatedObject.Children
         If TypeOf StackPanelChildren Is Expander Then
            Dim CurrExpander As Expander = DirectCast(StackPanelChildren, Expander)
            ExpanderList.Add(CurrExpander)
            AddHandler CurrExpander.Expanded, AddressOf Expander_Expanded
         Else
            Dim OtherControl As FrameworkElement = DirectCast(StackPanelChildren, FrameworkElement)
            OtherControlList.Add(OtherControl)
         End If
      Next
   End Sub

   Private Sub Expander_Expanded(sender As Object, e As System.Windows.RoutedEventArgs)
      Dim SelectedExpander As Expander = DirectCast(sender, Expander)
      If Me.AssociatedObject.Orientation = Orientation.Vertical Then
         VerticalVerifyDimension(SelectedExpander)
      Else
         HorizontalVerifyDimension(SelectedExpander)
      End If
   End Sub

   Private Sub VerticalVerifyDimension(SelectedExpander As Expander)
      Dim AssociatedObjectElement As FrameworkElement = DirectCast(AssociatedObject, FrameworkElement)
      AssociatedObjectElement.Measure(New Size(Double.PositiveInfinity, Double.PositiveInfinity))
      Dim TotalCurrentHeight = AssociatedObjectElement.DesiredSize.Height
      ' Aggiungo la dimensione del contenuto dell'expander selezionato
      Dim SelectedContent As FrameworkElement = DirectCast(SelectedExpander.Content, FrameworkElement)
      SelectedContent.Measure(New Size(Double.PositiveInfinity, Double.PositiveInfinity))
      TotalCurrentHeight += SelectedContent.DesiredSize.Height
      ' Aggiungo il padding del contenuto
      TotalCurrentHeight += (SelectedExpander.Padding.Top + SelectedExpander.Padding.Bottom)
      If TotalCurrentHeight < Me.AssociatedObject.MaxHeight Then
         Return
      End If
      For Index = ExpanderList.Count - 1 To 0 Step -1
         If TotalCurrentHeight > Me.AssociatedObject.MaxHeight Then
            If ExpanderList(Index) IsNot SelectedExpander AndAlso ExpanderList(Index).IsExpanded = True Then
               'TotalCurrentHeight -= ExpanderList(Index).ActualHeight
               ExpanderList(Index).IsExpanded = False
               Dim CurrExpanderContent As FrameworkElement = DirectCast(ExpanderList(Index).Content, FrameworkElement)
               CurrExpanderContent.Measure(New Size(Double.PositiveInfinity, Double.PositiveInfinity))
               TotalCurrentHeight -= CurrExpanderContent.DesiredSize.Height
               ' Sottraggo anche i padding
               TotalCurrentHeight -= (ExpanderList(Index).Padding.Top + ExpanderList(Index).Padding.Bottom)
            End If
         Else
            Exit For
         End If
      Next


      'Dim TotalDimension As Double = 0
      ''Aggiungo la dimensione di tutti gli Header
      'For Each Expander In ExpanderList
      '   If Expander IsNot SelectedExpander Then
      '      If Not Expander.IsExpanded Then
      '         TotalDimension += Expander.ActualHeight
      '      Else
      '         Dim ExpanderContent As FrameworkElement = DirectCast(Expander.Content, FrameworkElement)
      '         ExpanderContent.Measure(New Size(Double.PositiveInfinity, Double.PositiveInfinity))
      '         TotalDimension += (Expander.ActualHeight - ExpanderContent.DesiredSize.Height)
      '      End If
      '   Else
      '      TotalDimension += Expander.ActualHeight
      '   End If
      'Next
      '' Aggiungo la dimensione dei controlli fissi (non Expander)
      'For Each OtherControl In OtherControlList
      '   TotalDimension += OtherControl.ActualHeight
      'Next
      '' Aggiungo la dimensione del contenuto dell'expander selezionato
      'Dim SelectedContent As FrameworkElement = DirectCast(SelectedExpander.Content, FrameworkElement)
      'SelectedContent.Measure(New Size(Double.PositiveInfinity, Double.PositiveInfinity))
      'TotalDimension += SelectedContent.DesiredSize.Height
      '' Verifico per tutti gli expander (tranne quello selezionato) a partire dal primo se sono espansi e nel caso se la loro dimensione totale li fa stare nello spazio disponibile
      'Dim Index As Integer = 0
      'For Index = 0 To ExpanderList.Count - 1
      '   If ExpanderList(Index) IsNot SelectedExpander Then
      '      If ExpanderList(Index).IsExpanded Then
      '         Dim ExpanderContent As FrameworkElement = DirectCast(ExpanderList(Index).Content, FrameworkElement)
      '         TotalDimension += ExpanderContent.ActualHeight
      '         If TotalDimension > Me.AssociatedObject.MaxHeight Then
      '            Exit For
      '         End If
      '      End If
      '   End If
      'Next
      'For CancelIndex = Index To ExpanderList.Count - 1
      '   If ExpanderList(CancelIndex) IsNot SelectedExpander Then
      '      ExpanderList(CancelIndex).IsExpanded = False
      '   End If
      'Next
   End Sub

   Private Sub HorizontalVerifyDimension(SelectedExpander As Expander)
      Dim TotalDimension As Double = 0
      'Aggiungo la dimensione di tutti gli Header
      For Each Expander In ExpanderList
         If Expander IsNot SelectedExpander Then
            If Not Expander.IsExpanded Then
               TotalDimension += Expander.ActualWidth
            Else
               Dim ExpanderContent As FrameworkElement = DirectCast(Expander.Content, FrameworkElement)
               ExpanderContent.Measure(New Size(Double.PositiveInfinity, Double.PositiveInfinity))
               TotalDimension += (Expander.ActualWidth - ExpanderContent.DesiredSize.Width)
            End If
         Else
            TotalDimension += Expander.ActualWidth
         End If
      Next
      ' Aggiungo la dimensione dei controlli fissi (non Expander)
      For Each OtherControl In OtherControlList
         TotalDimension += OtherControl.ActualWidth
      Next
      ' Aggiungo la dimensione del contenuto dell'expander selezionato
      Dim SelectedContent As FrameworkElement = DirectCast(SelectedExpander.Content, FrameworkElement)
      SelectedContent.Measure(New Size(Double.PositiveInfinity, Double.PositiveInfinity))
      TotalDimension += SelectedContent.DesiredSize.Width
      ' Verifico per tutti gli expander (tranne quello selezionato) a partire dal primo se sono espansi e nel caso se la loro dimensione totale li fa stare nello spazio disponibile
      Dim Index As Integer = 0
      For Index = 0 To ExpanderList.Count - 1
         If ExpanderList(Index) IsNot SelectedExpander Then
            If ExpanderList(Index).IsExpanded Then
               Dim ExpanderContent As FrameworkElement = DirectCast(ExpanderList(Index).Content, FrameworkElement)
               TotalDimension += ExpanderContent.ActualWidth
               If TotalDimension > Me.AssociatedObject.ActualWidth Then
                  Exit For
               End If
            End If
         End If
      Next
      For CancelIndex = Index To ExpanderList.Count - 1
         If ExpanderList(CancelIndex) IsNot SelectedExpander Then
            ExpanderList(CancelIndex).IsExpanded = False
         End If
      Next
   End Sub

End Class