Imports System.Runtime.InteropServices
Imports System.Text
Imports System.Windows.Interop
Imports System.Xml.Serialization

Public Class EgtWindowV

   Private Const WM_GETMINMAXINFO As Integer = &H24
   Private Const MONITOR_DEFAULTTONEAREST As UInteger = &H2
   Private Const SW_SHOWNORMAL As Integer = 1
   Private Const SW_SHOWMINIMIZED As Integer = 2

   <Serializable>
   <StructLayout(LayoutKind.Sequential)>
   Public Structure RECT

      Public Left As Integer
      Public Top As Integer
      Public Right As Integer
      Public Bottom As Integer

      Public Sub New(ByVal left As Integer, ByVal top As Integer, ByVal right As Integer, ByVal bottom As Integer)
         Me.Left = left
         Me.Top = top
         Me.Right = right
         Me.Bottom = bottom
      End Sub

   End Structure

   <StructLayout(LayoutKind.Sequential)>
   Public Structure MONITORINFO

      Public cbSize As Integer
      Public rcMonitor As RECT
      Public rcWork As RECT
      Public dwFlags As UInteger

   End Structure

   <Serializable>
   <StructLayout(LayoutKind.Sequential)>
   Public Structure POINT

      Public X As Integer
      Public Y As Integer

      Public Sub New(ByVal x As Integer, ByVal y As Integer)
         Me.X = x
         Me.Y = y
      End Sub

   End Structure

   <StructLayout(LayoutKind.Sequential)>
   Public Structure MINMAXINFO

      Public ptReserved As POINT
      Public ptMaxSize As POINT
      Public ptMaxPosition As POINT
      Public ptMinTrackSize As POINT
      Public ptMaxTrackSize As POINT

   End Structure

   <Serializable>
   <StructLayout(LayoutKind.Sequential)>
   Public Structure WINDOWPLACEMENT

      Public length As Integer
      Public flags As Integer
      Public showCmd As Integer
      Public minPosition As POINT
      Public maxPosition As POINT
      Public normalPosition As RECT

   End Structure

   Private Shared encoding As Encoding = New UTF8Encoding()
   Private Shared serializer As XmlSerializer = New XmlSerializer(GetType(WINDOWPLACEMENT))


#Region "CONSTRUCTOR"

   Sub New()
      ' Funzione che interpreta l'xaml
      InitializeComponent()
      AddHandler Me.Loaded, AddressOf MainWindowV_Loaded
      AddHandler Me.ContentRendered, AddressOf MainWindowV_ContentRendered
      AddHandler Me.StateChanged, AddressOf Window_StateChanged
      AddHandler Me.Closing, AddressOf MainWindowV_Closing
      AddHandler Me.Closed, AddressOf MainWindowV_Closed
      Me.RefreshMaximizeRestoreButton()
   End Sub

#End Region    ' CONSTRUCTOR

#Region "METHODS"

   <DllImport("user32.dll")>
   Private Shared Function MonitorFromWindow(ByVal handle As IntPtr, ByVal flags As UInteger) As IntPtr
   End Function
   <DllImport("user32.dll")>
   Private Shared Function GetMonitorInfo(ByVal hMonitor As IntPtr, ByRef lpmi As MONITORINFO) As Boolean
   End Function
   <DllImport("user32.dll")>
   Private Shared Function SetWindowPlacement(ByVal hWnd As IntPtr, <[In]> ByRef lpwndpl As WINDOWPLACEMENT) As Boolean
   End Function
   <DllImport("user32.dll")>
   Private Shared Function GetWindowPlacement(ByVal hWnd As IntPtr, <Out> ByRef lpwndpl As WINDOWPLACEMENT) As Boolean
   End Function

   Protected Overrides Sub OnSourceInitialized(ByVal e As EventArgs)
      MyBase.OnSourceInitialized(e)
      CType(PresentationSource.FromVisual(Me), HwndSource).AddHook(AddressOf HookProc)
      Dim sPlacement As String = ""
      GetMainPrivateProfileString(S_GENERAL, K_WINPLACE, "", sPlacement)
      If Not String.IsNullOrWhiteSpace(sPlacement) Then
         SetPlacement(sPlacement)
      End If

   End Sub

   Public Shared Function HookProc(ByVal hwnd As IntPtr, ByVal msg As Integer, ByVal wParam As IntPtr, ByVal lParam As IntPtr, ByRef handled As Boolean) As IntPtr
      If msg = WM_GETMINMAXINFO Then
         Dim mmi As MINMAXINFO = CType(Marshal.PtrToStructure(lParam, GetType(MINMAXINFO)), MINMAXINFO)
         Dim monitor As IntPtr = MonitorFromWindow(hwnd, MONITOR_DEFAULTTONEAREST)

         If monitor <> IntPtr.Zero Then
            Dim monitorInfo As MONITORINFO = New MONITORINFO()
            monitorInfo.cbSize = Marshal.SizeOf(GetType(MONITORINFO))
            GetMonitorInfo(monitor, monitorInfo)
            Dim rcWorkArea As RECT = monitorInfo.rcWork
            Dim rcMonitorArea As RECT = monitorInfo.rcMonitor
            mmi.ptMaxPosition.X = Math.Abs(rcWorkArea.Left - rcMonitorArea.Left)
            mmi.ptMaxPosition.Y = Math.Abs(rcWorkArea.Top - rcMonitorArea.Top)
            mmi.ptMaxSize.X = Math.Abs(rcWorkArea.Right - rcWorkArea.Left)
            mmi.ptMaxSize.Y = Math.Abs(rcWorkArea.Bottom - rcWorkArea.Top)
         End If

         Marshal.StructureToPtr(mmi, lParam, True)
      End If

      Return IntPtr.Zero
   End Function

   Shared Sub SetPlacement(ByVal windowHandle As IntPtr, ByVal placementXml As String)
      If String.IsNullOrEmpty(placementXml) Then
         Return
      End If

      Dim placement As WINDOWPLACEMENT
      Try
         placement = StringToPlacement(placementXml)
         'Using memoryStream As TextReader = New StringReader(placementXml)
         '   placement = CType(serializer.Deserialize(memoryStream), WINDOWPLACEMENT)
         'End Using

         placement.length = Marshal.SizeOf(GetType(WINDOWPLACEMENT))
         placement.flags = 0
         placement.showCmd = (If(placement.showCmd = SW_SHOWMINIMIZED, SW_SHOWNORMAL, placement.showCmd))
         SetWindowPlacement(windowHandle, placement)
      Catch __unusedInvalidOperationException1__ As InvalidOperationException
      End Try

   End Sub

   Private Shared Function PlacementToString(Placement As WINDOWPLACEMENT) As String
      Dim sPlacement As String = ""
      sPlacement = Placement.length.ToString() & ";" &
                   Placement.flags.ToString() & ";" &
                   Placement.showCmd.ToString() & ";"
      sPlacement &= PointToString(Placement.minPosition) & ";"
      sPlacement &= PointToString(Placement.maxPosition) & ";"
      sPlacement &= RectToString(Placement.normalPosition)
      Return sPlacement
   End Function

   Private Shared Function PointToString(Point As POINT) As String
      Dim sPoint As String = ""
      sPoint = Point.X.ToString() & "," &
               Point.Y.ToString()
      Return sPoint
   End Function

   Private Shared Function RectToString(Rect As RECT) As String
      Dim sRect As String = ""
      sRect = Rect.Left.ToString() & "," &
              Rect.Top.ToString() & "," &
              Rect.Right.ToString() & "," &
              Rect.Bottom.ToString()
      Return sRect
   End Function

   Shared Function GetPlacement(ByVal windowHandle As IntPtr) As String
      Dim placement As WINDOWPLACEMENT = New WINDOWPLACEMENT()
      GetWindowPlacement(windowHandle, placement)
      Return PlacementToString(placement)

      'Using TextWriter As StringWriter = New StringWriter()
      '   serializer.Serialize(TextWriter, placement)
      '   Return TextWriter.ToString().Replace(Environment.NewLine, "")
      'End Using

   End Function

   Private Shared Function StringToPlacement(sPlacement As String) As WINDOWPLACEMENT
      Dim Placement As WINDOWPLACEMENT
      Dim sPlacementArray As String() = sPlacement.Split(";"c)
      If sPlacementArray.Length < 5 Then
         Placement.normalPosition = New RECT(100, 100, 800, 800)
         Return Placement
      End If
      Integer.TryParse(sPlacementArray(0), Placement.length)
      Integer.TryParse(sPlacementArray(1), Placement.flags)
      Integer.TryParse(sPlacementArray(2), Placement.showCmd)
      Placement.minPosition = StringToPoint(sPlacementArray(3))
      Placement.maxPosition = StringToPoint(sPlacementArray(4))
      Placement.normalPosition = StringToRect(sPlacementArray(5))
      Return Placement
   End Function

   Private Shared Function StringToPoint(sPoint As String) As POINT
      Dim sPointArray As String() = sPoint.Split(","c)
      Dim nX As Integer = 0
      Dim nY As Integer = 0
      Integer.TryParse(sPointArray(0), nX)
      Integer.TryParse(sPointArray(1), nY)
      Return New POINT(nX, nY)
   End Function

   Private Shared Function StringToRect(sRect As String) As RECT
      Dim sRectArray As String() = sRect.Split(","c)
      Dim nLeft As Integer = 0
      Dim nTop As Integer = 0
      Dim nRight As Integer = 0
      Dim nBottom As Integer = 0
      Integer.TryParse(sRectArray(0), nLeft)
      Integer.TryParse(sRectArray(1), nTop)
      Integer.TryParse(sRectArray(2), nRight)
      Integer.TryParse(sRectArray(3), nBottom)
      Return New RECT(nLeft, nTop, nRight, nBottom)
   End Function

   Public Sub SetPlacement(ByVal placementXml As String)
      SetPlacement(New WindowInteropHelper(Me).Handle, placementXml)
   End Sub

   Public Function GetPlacement() As String
      Return GetPlacement(New WindowInteropHelper(Me).Handle)
   End Function

   Private Sub RefreshMaximizeRestoreButton()
      If Me.WindowState = WindowState.Maximized Then
         Me.maximizeButton.Visibility = Visibility.Collapsed
         Me.restoreButton.Visibility = Visibility.Visible
      Else
         Me.maximizeButton.Visibility = Visibility.Visible
         Me.restoreButton.Visibility = Visibility.Collapsed
      End If
   End Sub

#End Region    ' METHODS

#Region "EVENTS"

   Private Sub OnMinimizeButtonClick(ByVal sender As Object, ByVal e As RoutedEventArgs)
      Me.WindowState = WindowState.Minimized
   End Sub

   Private Sub OnMaximizeRestoreButtonClick(ByVal sender As Object, ByVal e As RoutedEventArgs)
      If Me.WindowState = WindowState.Maximized Then
         Me.WindowState = WindowState.Normal
      Else
         Me.WindowState = WindowState.Maximized
      End If
   End Sub

   Private Sub Window_StateChanged(ByVal sender As Object, ByVal e As EventArgs)
      Me.RefreshMaximizeRestoreButton()
   End Sub

   Private Sub OnCloseButtonClick(ByVal sender As Object, ByVal e As RoutedEventArgs)
      Me.Close()
   End Sub

   Private Sub MainWindowV_Closing(sender As Object, e As System.ComponentModel.CancelEventArgs)
      If (Keyboard.Modifiers And ModifierKeys.Alt) = ModifierKeys.Alt OrElse Keyboard.IsKeyDown(Key.F4) Then
         e.Cancel = True
         Return
      End If
      WriteMainPrivateProfileString(S_GENERAL, K_WINPLACE, GetPlacement())
   End Sub

   Private Sub MainWindowV_Closed(sender As Object, e As EventArgs)
      EgtOutLog("Exit")
   End Sub

#End Region    ' EVENTS

End Class