Imports System.IO
Imports DevExpress
Imports DevExpress.Spreadsheet
Imports DevExpress.XtraRichEdit.Commands
Imports DevExpress.Office.Utils
Imports GdPicture14
Imports DigitalData.Modules.Logging
Imports DigitalData.Modules.Messaging
Imports DigitalData.Modules.Config

Public Class DocumentViewer
    Private Enum ZoomMode
        Zoom50
        Zoom100
        Zoom150
        Zoom200
        ZoomSelectedArea
        ZoomFitToViewer
        ZoomFitWidth
        ZoomFitHeight
    End Enum

    Private Enum ViewerMode
        GDPicture
        Excel
    End Enum

    Private Enum FileLoadMode
        File
        Stream
    End Enum

    Public ReadOnly Property PdfViewer As GdViewer
        Get
            Return GdViewer
        End Get
    End Property

    Private _logConfig As LogConfig
    Private _logger As Logger
    Private _Config As ConfigManager(Of Config)
    Private _email As Email2

    Private _ViewerMode As ViewerMode

    Private _licenseKey As String = String.Empty
    Private _licenseManager As New GdPicture14.LicenseManager()

    Private _Search As Search
    Private _Annotations As Annotations
    Private _AnnotationsPending As Boolean = False

    Private _ToolbarSettings As New ToolbarSettings

    Private _hide_file_info_from_user As Boolean = False

    Private _FileStream As Stream
    Private _FilePath As String
    Private _FileInfo As FileInfo
    Private _FileLoadMode As FileLoadMode = FileLoadMode.File

    ' List of all created temp files when converting msg files
    Private _TempFiles As New List(Of String)

    Private Sub DocumentViewer_Load(sender As Object, e As EventArgs) Handles Me.Load
        UpdateMainUi()
    End Sub
    'hallo
    Public Class ToolbarSettings
        Public Property ShowPrintButton As Boolean = True
        Public Property ShowFitWidthButton As Boolean = True
        Public Property ShowFitPageButton As Boolean = True
        Public Property ShowZoomButton As Boolean = True
        Public Property ShowRotateButton As Boolean = True
        Public Property ShowFlipButton As Boolean = True
        Public Property ShowSearchButton As Boolean = True
        Public Property ShowSettingButton As Boolean = True
    End Class

    Public Property FileLoaded As Boolean = False
    Public ReadOnly Property AnnotationsSaved As Boolean
        Get
            Return Not _AnnotationsPending
        End Get
    End Property

    ''' <summary>
    ''' Initialize the Viewer
    ''' </summary>
    ''' <param name="pLogConfig">A LogConfig object</param>
    ''' <param name="pLicenseKey">The GDPicture.NET License Key</param>
    Public Function Init(pLogConfig As LogConfig, pLicenseKey As String, Optional pToolbarSettings As ToolbarSettings = Nothing) As Boolean
        _logConfig = pLogConfig
        _logger = pLogConfig.GetLogger()

        If pToolbarSettings Is Nothing Then
            pToolbarSettings = New ToolbarSettings
        End If

        Try

            _email = New Email2(pLogConfig)
            If pLicenseKey = String.Empty Then
                _logger.Warn("License key was not provided during init!")
                Return False
            End If
            _licenseKey = pLicenseKey
            _licenseManager.RegisterKEY(_licenseKey)
            _Annotations = New Annotations(pLogConfig)
            _Search = New Search(pLogConfig, GdViewer)
            _ToolbarSettings = pToolbarSettings

            Dim oConfigPath = ConfigPath()
            _Config = New ConfigManager(Of Config)(pLogConfig, oConfigPath)
            Return True
        Catch ex As Exception
            _logger.Error(ex)
            Return False
        End Try
    End Function

    ''' <summary>
    ''' Load a file from a path and display it
    ''' </summary>
    Public Sub LoadFile(FilePath As String)
        FileLoaded = False

        If _licenseKey = String.Empty Then
            _logger.Warn("License key was not provided. File {0} not loaded.", FilePath)
            Exit Sub
        End If

        If FilePath Is Nothing OrElse FilePath.Trim().Length = 0 Then
            _logger.Warn("FilePath was not provided. File not loaded.")
            Exit Sub
        End If

        _FilePath = FilePath
        _FileLoadMode = FileLoadMode.File
        _FileInfo = New FileInfo(FilePath)

        _logger.Info("Loading File [{0}] from Filesystem", FilePath)
        FileLoaded = DoLoadFile(FilePath)

        SetViewerMode(_FileInfo.Extension)
        UpdateMainUi()
    End Sub

    ''' <summary>
    ''' Load a file from a stream and display it
    ''' </summary>
    Public Sub LoadFile(FileName As String, Stream As Stream)
        FileLoaded = False



        Dim oExtension As String = FileName.Substring(FileName.LastIndexOf("."))

        _FileStream = Stream
        _FileLoadMode = FileLoadMode.Stream

        _logger.Info("Loading file [{0}] from Stream", FileName)
        FileLoaded = DoLoadFile(Stream, oExtension)

        SetViewerMode(oExtension)
        UpdateMainUi()
    End Sub

    ''' <summary>
    ''' Terminate Viewer, freeing up resources and deleting temp files
    ''' </summary>
    Public Sub Done()
        Try
            _logger.Debug("Done: Deleting Temp Files")
            DeleteTempFiles()

            _logger.Debug("Done: Closing Documents")
            FreeFile()

            _logger.Debug("Done: Triggering GC")
            GC.Collect()
        Catch ex As Exception
            _logger.Warn("Error while cleaning up DocumentViewer")
            _logger.Error(ex)
        End Try
    End Sub

    Public Function AddAnnotation(pText As String) As Boolean
        Dim oFontStyle = FontStyle.Regular
        Dim oFontColor = Color.Black
        Dim oFontFamily = "Arial"
        Dim oFontSize = 8
        Dim oBorderColor = Color.Red
        Dim oBackColor = Color.LightYellow
        Dim oOpacity = 1.0F
        Dim oRotation = 0.0F

        GdViewer.AddTextAnnotationInteractive(pText, oFontColor, oFontFamily, oFontStyle, oFontSize, Fill:=True, oBorderColor, oBackColor, oOpacity, oRotation)
        _AnnotationsPending = True

        Return True
    End Function

    Public Function Save() As Boolean
        Dim oSaveResult As GdPictureStatus = GdPictureStatus.OK

        If GdViewer.BurnAnnotationsToPage(True, False) = GdPictureStatus.OK Then
            If _FileLoadMode = FileLoadMode.Stream Then
                oSaveResult = GdViewer.SaveDocumentToPDF(_FileStream)
            Else
                oSaveResult = GdViewer.SaveDocumentToPDF(_FilePath)
            End If
        End If

        If oSaveResult = GdPictureStatus.OK Then
            _AnnotationsPending = False
            Return True
        Else
            Return False
        End If
    End Function

    Public Sub CloseDocument()
        Try
            GdViewer.CloseDocument()

            _FileInfo = Nothing
            _FilePath = Nothing
            _FileStream = Nothing

            UpdateMainUi()
        Catch ex As Exception
            _logger.Error(ex)
        End Try
    End Sub

    ''' <summary>
    ''' Configures the viewer to hide the file path to the end-user.
    ''' </summary>
    ''' <param name="ViewOnly">
    ''' True means that all file info should be hidden from the end-user
    ''' False means the end user may see the filepath or other info about the file
    ''' </param>
    Public Sub SetViewOnly(ViewOnly As Boolean)
        If ViewOnly Then
            buttonPrint.Visibility = XtraBars.BarItemVisibility.Never
        Else
            buttonPrint.Visibility = XtraBars.BarItemVisibility.Always
        End If

        _hide_file_info_from_user = ViewOnly
    End Sub

    Public Sub SetAllowAnnotations(AllowAnnotations As Boolean)

    End Sub

    ''' <summary>
    ''' DEPRECATED: Use SetViewOnly
    ''' </summary>
    Public Sub RightViewOnly(ViewOnly As Boolean)
        SetViewOnly(ViewOnly)
    End Sub

    ''' <summary>
    ''' DEPRECATED: Use SetViewOnly
    ''' </summary>
    Public Sub RightOnlyView(ViewOnly As Boolean)
        SetViewOnly(ViewOnly)
    End Sub





#Region "Form Events"

    Private Sub btnFitWidth_Click(ByVal sender As Object, ByVal e As EventArgs) Handles buttonFitWidth.ItemClick
        FitToWidth()
        _Config.Config.PageFit = Config.PageFitSetting.FitWidth
        _Config.Save()
    End Sub

    Private Sub btnFitPage_Click(ByVal sender As Object, ByVal e As EventArgs) Handles buttonFitPage.ItemClick
        FitToPage()
        _Config.Config.PageFit = Config.PageFitSetting.FitPage
        _Config.Save()
    End Sub

    Private Sub btnOpen_Click(sender As Object, e As EventArgs)
        GdViewer.ZoomMode = ViewerZoomMode.ZoomModeWidthViewer
        GdViewer.DocumentAlignment = ViewerDocumentAlignment.DocumentAlignmentTopCenter

        If OpenFileDialog.ShowDialog() = DialogResult.OK Then
            GdViewer.DisplayFromFile(OpenFileDialog.FileName)
        End If

        GdViewer.Focus()
        UpdateMainUi()
    End Sub
    Private Sub btnFirstPage_Click(ByVal sender As System.Object, ByVal e As EventArgs) Handles buttonFirstPage.ItemClick
        GdViewer.DisplayFirstPage()
    End Sub

    Private Sub btnPreviousPage_Click(ByVal sender As System.Object, ByVal e As EventArgs) Handles buttonPrevPage.ItemClick
        _ViewerMode = ViewerMode.GDPicture
        GdViewer.DisplayPreviousPage()
    End Sub

    Private Sub btnNextPage_Click(ByVal sender As System.Object, ByVal e As EventArgs) Handles buttonNextPage.ItemClick
        _ViewerMode = ViewerMode.GDPicture
        GdViewer.DisplayNextPage()
    End Sub

    Private Sub btnLastPage_Click(ByVal sender As System.Object, ByVal e As EventArgs) Handles buttonLastPage.ItemClick
        GdViewer.DisplayLastPage()
    End Sub

    Private Sub tbCurrentPage_Leave(ByVal sender As System.Object, ByVal e As EventArgs) Handles txtCurrentPage.EditValueChanged
        Dim page As Integer = 0
        If Integer.TryParse(txtCurrentPage.EditValue, page) Then
            If page > 0 And page <= GdViewer.PageCount Then
                GdViewer.DisplayPage(page)
                UpdateaNavigationToolbar()
            End If
        End If
    End Sub

    Private Sub GdViewer1_PageChanged() Handles GdViewer.PageChanged
        UpdateaNavigationToolbar()
    End Sub

    Private Sub GdViewer1_AfterZoomChange() Handles GdViewer.AfterZoomChange
        UpdateaNavigationToolbar()
        If GdViewer.MouseMode = ViewerMouseMode.MouseModeAreaZooming Then
            GdViewer.MouseMode = ViewerMouseMode.MouseModePan
        End If
    End Sub

    Private Sub btnZoomOut_Click(sender As Object, e As EventArgs) Handles buttonZoomOut.ItemClick
        _ViewerMode = ViewerMode.GDPicture
        GdViewer.ZoomOUT()
    End Sub

    Private Sub btnZoomIn_Click(sender As Object, e As EventArgs) Handles buttonZoomIn.ItemClick
        _ViewerMode = ViewerMode.GDPicture
        GdViewer.ZoomIN()
    End Sub

    Private Sub btnPrint_Click(sender As Object, e As EventArgs) Handles buttonPrint.ItemClick
        If GdViewer.PageCount = 0 Then
            Return
        End If

        GdViewer.PrintDialog()
    End Sub

    Private Sub btnRotateLeft_Click(sender As Object, e As EventArgs) Handles buttonRotateLeft.ItemClick
        GdViewer.Rotate(RotateFlipType.Rotate270FlipNone)
    End Sub

    Private Sub btnRotateRight_Click(sender As Object, e As EventArgs) Handles buttonRotateRight.ItemClick
        GdViewer.Rotate(RotateFlipType.Rotate90FlipNone)
    End Sub

    Private Sub btnFlipX_Click(sender As Object, e As EventArgs) Handles buttonFlipX.ItemClick
        GdViewer.Rotate(RotateFlipType.RotateNoneFlipX)
    End Sub

    Private Sub btnFlipY_Click(sender As Object, e As EventArgs) Handles buttonFlipY.ItemClick
        GdViewer.Rotate(RotateFlipType.RotateNoneFlipY)
    End Sub

    Private Sub GdViewer1_TransferEnded(ByVal status As GdPictureStatus, ByVal download As System.Boolean) Handles GdViewer.TransferEnded
        GdViewer.Focus()
        UpdateMainUi()
    End Sub

    Private Sub AddSearchRegion(ByVal occurence As Integer, ByVal leftCoordinate As Single, ByVal topCoordinate As Single, ByVal regionWidth As Single, ByVal regionheight As Single, ByVal ensureVisibility As Boolean)
        Dim searchRegion As Integer = GdViewer.AddRegionInches("SearchResult" & occurence, leftCoordinate, topCoordinate, regionWidth, regionheight, ForegroundMixMode.ForegroundMixModeMASKPEN, Color.Yellow)
        GdViewer.SetRegionEditable(searchRegion, False)
        If ensureVisibility Then
            GdViewer.EnsureRegionVisibility(searchRegion)
        End If
    End Sub

    Private Sub btnSettings_Click(ByVal sender As Object, ByVal e As EventArgs) Handles buttonSettings.ItemClick
        Using frmSettings As New frmViewerSettings(GdViewer)
            frmSettings.ShowDialog(Me)
        End Using
        UpdateaNavigationToolbar()
    End Sub
#End Region

#Region "Private Functions"
    Private Function ConfigPath() As String
        Return Path.Combine(Application.UserAppDataPath, "DocumentViewer")
    End Function

    Private Sub UpdateaNavigationToolbar()
        Try
            Dim oCurrentZoom As Double = GdViewer.Zoom
            Dim oCurrentPage As Integer = GdViewer.CurrentPage
            Dim oPageCount As Integer = GdViewer.PageCount
            txtCurrentPage.EditValue = oCurrentPage
            labelPageCount.Caption = $"/ {oPageCount}"

            If oCurrentPage = oPageCount Then
                buttonLastPage.Enabled = False
                buttonNextPage.Enabled = False
                buttonPrevPage.Enabled = True
                buttonFirstPage.Enabled = True
            ElseIf oCurrentPage = 1 Then
                buttonPrevPage.Enabled = False
                buttonFirstPage.Enabled = False
                buttonLastPage.Enabled = True
                buttonNextPage.Enabled = True
            Else
                buttonPrevPage.Enabled = True
                buttonFirstPage.Enabled = True
                buttonLastPage.Enabled = True
                buttonNextPage.Enabled = True
            End If
        Catch ex As Exception
            _logger.Error(ex)
        End Try
    End Sub

    Public Sub DeleteTempFiles()
        For Each oFile In _TempFiles
            Try
                _logger.Debug("Deleting temp file [{0}]", oFile)
                File.Delete(oFile)
            Catch ex As Exception
                _logger.Warn("Could not delete temp file [{0}]", oFile)
            End Try
        Next
    End Sub

    Private Sub SetViewerMode(Extension As String)
        Select Case Extension.ToUpper
            Case "CSV"
                _ViewerMode = ViewerMode.Excel
            Case Else
                _ViewerMode = ViewerMode.GDPicture
        End Select
    End Sub
    Private Sub FreeFile()
        Try
            If Len(_FilePath) = 0 OrElse _FileInfo Is Nothing Then
                Exit Sub
            End If
            Dim oExtension As String = _FileInfo.Extension.ToUpper
            Select Case _ViewerMode
                Case ViewerMode.Excel
                    _logger.Debug("Closing Excel Editor")
                    SpreadsheetControl1.CreateNewDocument()
                Case Else
                    _logger.Debug("Closing GDPicture Viewer")
                    GdViewer.CloseDocument()
            End Select
        Catch ex As Exception
            _logger.Warn($"Unexpected error in FreeFile: {ex.Message}")
        End Try
    End Sub
    Private Function DoLoadFile(FilePath As String) As Boolean
        Try
            Dim oFileInfo = New FileInfo(FilePath)
            Dim oExtension As String = oFileInfo.Extension.ToUpper

            lbFileNotLoaded.Visible = False

            SpreadsheetControl1.Visible = False
            SpreadsheetControl1.Dock = DockStyle.None

            Select Case oExtension.ToUpper
                Case ".CSV"
                    Dim oFormat = GetSpreadsheetFormat(oExtension)
                    SpreadsheetControl1.LoadDocument(FilePath, oFormat)

                    Dim oRange = SpreadsheetControl1.ActiveWorksheet.GetUsedRange()
                    oRange.AutoFitColumns()

                    SpreadsheetControl1.Visible = True
                    SpreadsheetControl1.Dock = DockStyle.Fill

                Case Else
                    GdViewer.ZoomMode = ViewerZoomMode.ZoomModeWidthViewer
                    GdViewer.DocumentAlignment = ViewerDocumentAlignment.DocumentAlignmentTopCenter
                    GdViewer.ForceTemporaryMode = True
                    GdViewer.AnnotationDropShadow = True
                    GdViewer.BackColor = Color.White

                    If GdViewer.DisplayFromFile(FilePath) <> GdPictureStatus.OK Then
                        Dim oFileName = IO.Path.GetFileName(FilePath)
                        lbFileNotLoaded.Text = String.Format("Datei konnte nicht geladen werden:{0}{1}", vbCrLf, oFileName)
                        lbFileNotLoaded.Visible = True
                    End If

            End Select

            UpdateMainUi()

            Return True
        Catch ex As Exception
            _logger.Error(ex)
            Return False
        End Try
    End Function

    Private Sub FitToPage()
        _ViewerMode = ViewerMode.GDPicture
        GdViewer.ZoomMode = ViewerZoomMode.ZoomModeFitToViewer
    End Sub

    Private Sub FitToWidth()
        _ViewerMode = ViewerMode.GDPicture
        GdViewer.ZoomMode = ViewerZoomMode.ZoomModeWidthViewer
    End Sub

    Private Function DoLoadFile(Stream As Stream, Extension As String) As Boolean
        Try

            SpreadsheetControl1.Visible = False
            SpreadsheetControl1.Dock = DockStyle.None

            Select Case Extension.ToUpper

                Case ".CSV"
                    SpreadsheetControl1.LoadDocument(Stream, GetSpreadsheetFormat(Extension))

                    Dim oRange = SpreadsheetControl1.ActiveWorksheet.GetUsedRange()
                    oRange.AutoFitColumns()

                    SpreadsheetControl1.Visible = True
                    SpreadsheetControl1.Dock = DockStyle.Fill

                Case Else
                    GdViewer.ZoomMode = ViewerZoomMode.ZoomModeWidthViewer
                    GdViewer.DocumentAlignment = ViewerDocumentAlignment.DocumentAlignmentTopCenter
                    GdViewer.ForceTemporaryMode = True
                    GdViewer.AnnotationDropShadow = True

                    GdViewer.DisplayFromStream(Stream)

            End Select

            UpdateMainUi()

            Return True
        Catch ex As Exception
            _logger.Error(ex)
            Return False
        End Try
    End Function

    Private Function GetSpreadsheetFormat(Extension) As Spreadsheet.DocumentFormat
        Dim oFormat As Spreadsheet.DocumentFormat = Spreadsheet.DocumentFormat.Undefined

        Select Case Extension.ToUpper
            Case ".XLSX" : oFormat = Spreadsheet.DocumentFormat.Xlsx
            Case ".XLS" : oFormat = Spreadsheet.DocumentFormat.Xls
            Case ".CSV" : oFormat = Spreadsheet.DocumentFormat.Csv
        End Select

        Return oFormat
    End Function

    Private Function GetDocumentFormat(Extension) As XtraRichEdit.DocumentFormat
        Dim oFormat As XtraRichEdit.DocumentFormat = XtraRichEdit.DocumentFormat.Undefined

        Select Case Extension.ToUpper
            Case ".EML" : oFormat = XtraRichEdit.DocumentFormat.Mht
            Case ".DOC" : oFormat = XtraRichEdit.DocumentFormat.Doc
            Case ".DOCX" : oFormat = XtraRichEdit.DocumentFormat.OpenXml
            Case ".ODT" : oFormat = XtraRichEdit.DocumentFormat.OpenDocument
            Case ".RTF" : oFormat = XtraRichEdit.DocumentFormat.Rtf
            Case ".TXT" : oFormat = XtraRichEdit.DocumentFormat.PlainText
        End Select

        Return oFormat
    End Function

    Private Function ToVisibility(pBoolean As Boolean) As XtraBars.BarItemVisibility
        If (pBoolean = True) Then
            Return XtraBars.BarItemVisibility.Always
        Else
            Return XtraBars.BarItemVisibility.Never
        End If
    End Function

    Private Sub UpdateMainUi()

        Select Case _Config?.Config?.PageFit
            Case Config.PageFitSetting.FitPage
                FitToPage()

            Case Config.PageFitSetting.FitWidth
                FitToWidth()

        End Select

        If _FileStream Is Nothing And _FilePath Is Nothing Then
            lbFileNotLoaded.Visible = False
        End If

        Select Case _ViewerMode
            Case ViewerMode.GDPicture
                ToolbarDocumentViewer.Visible = True

                buttonPrint.Visibility = ToVisibility(_ToolbarSettings.ShowPrintButton)
                buttonFitWidth.Visibility = ToVisibility(_ToolbarSettings.ShowFitWidthButton)
                buttonFitPage.Visibility = ToVisibility(_ToolbarSettings.ShowFitPageButton)
                buttonZoomIn.Visibility = ToVisibility(_ToolbarSettings.ShowZoomButton)
                buttonZoomOut.Visibility = ToVisibility(_ToolbarSettings.ShowZoomButton)
                buttonRotateLeft.Visibility = ToVisibility(_ToolbarSettings.ShowRotateButton)
                buttonRotateRight.Visibility = ToVisibility(_ToolbarSettings.ShowRotateButton)
                buttonFlipX.Visibility = ToVisibility(_ToolbarSettings.ShowFlipButton)
                buttonFlipY.Visibility = ToVisibility(_ToolbarSettings.ShowFlipButton)
                buttonSettings.Visibility = ToVisibility(_ToolbarSettings.ShowSettingButton)
                txtSearch.Visibility = ToVisibility(_ToolbarSettings.ShowSearchButton)
                btnSearch2.Visibility = ToVisibility(_ToolbarSettings.ShowSearchButton)
                btnNextHighlight.Visibility = ToVisibility(_ToolbarSettings.ShowSearchButton)
                btnPrevHighlight.Visibility = ToVisibility(_ToolbarSettings.ShowSearchButton)
                buttonFirstPage.Visibility = ToVisibility(True)
                buttonPrevPage.Visibility = ToVisibility(True)
                buttonNextPage.Visibility = ToVisibility(True)
                buttonLastPage.Visibility = ToVisibility(True)
                txtCurrentPage.Visibility = ToVisibility(True)

            Case ViewerMode.Excel
                ToolbarDocumentViewer.Visible = False

                buttonPrint.Visibility = ToVisibility(False)
                buttonFitWidth.Visibility = ToVisibility(False)
                buttonFitPage.Visibility = ToVisibility(False)
                buttonZoomIn.Visibility = ToVisibility(False)
                buttonZoomOut.Visibility = ToVisibility(False)
                buttonRotateLeft.Visibility = ToVisibility(False)
                buttonRotateRight.Visibility = ToVisibility(False)
                buttonFlipX.Visibility = ToVisibility(False)
                buttonFlipY.Visibility = ToVisibility(False)
                buttonFirstPage.Visibility = ToVisibility(False)
                buttonPrevPage.Visibility = ToVisibility(False)
                buttonNextPage.Visibility = ToVisibility(False)
                buttonLastPage.Visibility = ToVisibility(False)
                buttonSettings.Visibility = ToVisibility(False)
                txtCurrentPage.Visibility = ToVisibility(False)
                txtSearch.Visibility = ToVisibility(False)
                btnSearch2.Visibility = ToVisibility(False)
                btnNextHighlight.Visibility = ToVisibility(False)
                btnPrevHighlight.Visibility = ToVisibility(False)



        End Select
    End Sub

    Private Sub btnSearch2_ItemClick(sender As Object, e As XtraBars.ItemClickEventArgs) Handles btnSearch2.ItemClick
        If Not String.IsNullOrEmpty(txtSearch.EditValue) Then
            _Search.SearchAll(txtSearch.EditValue?.ToString)

        End If
    End Sub

    Private Sub btnPrevHighlight_ItemClick(sender As Object, e As XtraBars.ItemClickEventArgs) Handles btnPrevHighlight.ItemClick
        _Search.PrevHighlight()
    End Sub

    Private Sub btnNextHighlight_ItemClick(sender As Object, e As XtraBars.ItemClickEventArgs) Handles btnNextHighlight.ItemClick
        _Search.NextHighlight()
    End Sub

    Private Sub txtSearch_EditValueChanged(sender As Object, e As EventArgs) Handles txtSearch.EditValueChanged
        If String.IsNullOrEmpty(txtSearch.EditValue) Then
            btnPrevHighlight.Enabled = False
            btnNextHighlight.Enabled = False

        Else
            btnPrevHighlight.Enabled = True
            btnNextHighlight.Enabled = True
        End If
    End Sub
#End Region




End Class