' Copyright 2012 ESRI
' 
' All rights reserved under the copyright laws of the United States
' and applicable international laws, treaties, and conventions.
' 
' You may freely redistribute and use this sample code, with or
' without modification, provided you include the original copyright
' notice and use restrictions.
' 
' See the use restrictions.
' 

Imports System.Runtime.InteropServices

<Guid("A9FC5EB2-33F9-4941-AE69-775ECF688647"), _
 ClassInterface(ClassInterfaceType.None), _
 ProgId("RasterSyncExtensionVB.RasterSyncWorkspaceExtension")> _
Public Class RasterSyncWorkspaceExtension
  Implements IWorkspaceExtensionControl
  Implements IWorkspaceExtension2
  Implements IWorkspaceReplicaSyncEvents

#Region "Private Variables"
  ''' <summary>
  ''' Provides a weak reference to the extension's workspace.
  ''' </summary>
  Private workspaceHelper As IWorkspaceHelper = Nothing

  ''' <summary>
  ''' The name of the raster catalog to synchronize.
  ''' </summary>
  Private Const rasterCatalogName As String = "ras_cat"

  ''' <summary>
  ''' The name of the replica that requires raster synchronization.
  ''' </summary>
  Private Const rasterReplicaName As String = "myreplicaras"

  ''' <summary>
  ''' The name of the integer field in the raster catalogs that stores generation numbers.
  ''' </summary>
  Private Const genFieldName As String = "gen"
#End Region

#Region "IWorkspaceExtensionControl Members"
  ''' <summary>
  ''' Initializes the workspace extension.
  ''' </summary>
  ''' <param name="workspaceHelper">Provides a weak reference to the workspace.</param>
  Public Sub Init(ByVal workspaceHelper As IWorkspaceHelper) Implements IWorkspaceExtensionControl.Init
    Me.workspaceHelper = workspaceHelper
  End Sub

  ''' <summary>
  ''' Called to shutdown the extension.
  ''' </summary>
  Public Sub Shutdown() Implements IWorkspaceExtensionControl.Shutdown
    workspaceHelper = Nothing
  End Sub
#End Region

#Region "IWorkspaceExtension[2] Members"
  ''' <summary>
  ''' The name of the extension.
  ''' </summary>
  Public ReadOnly Property Name() As String _
  Implements IWorkspaceExtension.Name, IWorkspaceExtension2.Name
    Get
      Return "RasterSyncWorkspaceExtension"
    End Get
  End Property

  ''' <summary>
  ''' The extension's GUID.
  ''' </summary>
  Public ReadOnly Property GUID() As UID _
  Implements IWorkspaceExtension.GUID, IWorkspaceExtension2.GUID
    Get
      Dim uid As UID = New UIDClass()
      uid.Value = "{A9FC5EB2-33F9-4941-AE69-775ECF688647}"
      Return uid
    End Get
  End Property

  ''' <summary>
  ''' An enumerator of private dataset names used by the extension.
  ''' Not used in this implementation.
  ''' </summary>
  ''' <param name="datasetType">The dataset type.</param>
  ''' <returns>An enumerator of strings.</returns>
  Public ReadOnly Property PrivateDatasetNames(ByVal datasetType As esriDatasetType) As IEnumBSTR _
  Implements IWorkspaceExtension.PrivateDatasetNames, IWorkspaceExtension2.PrivateDatasetNames
    Get
      Return Nothing
    End Get
  End Property

  ''' <summary>
  ''' An enumerator of data dictionary names used by the extension.
  ''' Not used in this implementation.
  ''' </summary>
  Public ReadOnly Property DataDictionaryTableNames() As IEnumBSTR _
  Implements IWorkspaceExtension.DataDictionaryTableNames, IWorkspaceExtension2.DataDictionaryTableNames
    Get
      Return Nothing
    End Get
  End Property

  ''' <summary>
  ''' Indicates whether the extension owns a dataset type.
  ''' </summary>
  ''' <param name="datasetType">The type of dataset to check.</param>
  ''' <returns>False; this extension owns no dataset types.</returns>
  Public Function OwnsDatasetType(ByVal datasetType As esriDatasetType) As Boolean _
  Implements IWorkspaceExtension2.OwnsDatasetType
    Return False
  End Function

  ''' <summary>
  ''' Returns a reference to the extension's workspace.
  ''' </summary>
  Public ReadOnly Property Workspace() As IWorkspace _
  Implements IWorkspaceExtension2.Workspace
    Get
      Return workspaceHelper.Workspace
    End Get
  End Property
#End Region

#Region "IWorkspaceReplicaSyncEvents Members"
  ''' <summary>
  ''' Occurs in the replica geodatabase after data changes have been exported
  ''' from that replica geodatabase to a delta database.
  ''' Not used in this implementation.
  ''' </summary>
  Public Sub AfterExportingDataChanges(ByVal sourceReplica As IReplica, ByVal dataChangesSource As Object, ByVal deltaFile As Object) _
  Implements IWorkspaceReplicaSyncEvents.AfterExportingDataChanges
    ' Not used in this implementation.
  End Sub

  ''' <summary>
  ''' Occurs in the master geodatabase after data changes in either a replica
  ''' geodatabase or delta database are transferred to the master geodatabase.
  ''' </summary>
  ''' <param name="targetReplica">The target replica.</param>
  ''' <param name="dataChangesSource">A collection of changes made to the master geodatabase.</param>
  ''' <param name="oidMappingTable">Not used in this implementation.</param>
  ''' <param name="changesTable">Not used in this implemented.</param>
  Public Sub AfterSynchronizingDataChanges(ByVal targetReplica As IReplica, ByVal dataChangesSource As Object, _
  ByVal oidMappingTable As ITable, ByVal changesTable As ITable) _
  Implements IWorkspaceReplicaSyncEvents.AfterSynchronizingDataChanges
    ' Make sure that the correct replica is being synchronized.
    Dim replicaName As String = targetReplica.Name
    Dim unqualifiedReplicaName As String = replicaName.Substring(replicaName.LastIndexOf(".") + 1)
    If Not unqualifiedReplicaName.Equals(rasterReplicaName) Then
      Return
    End If

    ' Get the rasters to pull if connected synchronization is occurring.
    Dim dataChanges3 As IDataChanges3 = TryCast(dataChangesSource, IDataChanges3)
    If Not dataChanges3 Is Nothing Then
      ' Get the source's replicas.
      Dim sourceWorkspaceName As IName = CType(dataChanges3.ParentWorkspaceName, IName)
      Dim sourceWorkspace As IWorkspace = CType(sourceWorkspaceName.Open(), IWorkspace)
      Dim sourceWorkspaceReplicas As IWorkspaceReplicas = CType(sourceWorkspace, IWorkspaceReplicas)

      ' Get the replica generation numbers.
      Dim genBegin As Integer = 0
      Dim genEnd As Integer = 0
      Dim targetGen As Integer = 0
      dataChanges3.GenerationNumbers(genBegin, genEnd, targetGen)
      Dim queryFilter As IQueryFilter = New QueryFilterClass()
      queryFilter.WhereClause = String.Format("{0} > {1} or {0} is NULL", genFieldName, genBegin)

      ' Open a cursor to get the rasters to copy form the source.
      Dim sourceRasterWorkspaceEx As IRasterWorkspaceEx = CType(sourceWorkspace, IRasterWorkspaceEx)
      Dim sourceRasterCatalog As IRasterCatalog = sourceRasterWorkspaceEx.OpenRasterCatalog(rasterCatalogName)
      Dim sourceFeatureClass As IFeatureClass = CType(sourceRasterCatalog, IFeatureClass)
      Dim sourceGenFieldIndex As Integer = sourceFeatureClass.FindField(genFieldName)
      Dim sourceCursor As IFeatureCursor = sourceFeatureClass.Search(queryFilter, True)

      ' Open the target raster catalog.
      Dim targetRasterWorkspaceEx As IRasterWorkspaceEx = CType(workspaceHelper.Workspace, IRasterWorkspaceEx)
      Dim targetRasterCatalog As IRasterCatalog = targetRasterWorkspaceEx.OpenRasterCatalog(rasterCatalogName)
      Dim targetFeatureClass As IFeatureClass = CType(targetRasterCatalog, IFeatureClass)
      Dim targetGenFieldIndex As Integer = targetFeatureClass.FindField(genFieldName)
      Dim targetCursor As IFeatureCursor = targetFeatureClass.Insert(True)

      ' Copy the rasters from the source to the target.
      Dim sourceFeature As IFeature = sourceCursor.NextFeature()
      While Not sourceFeature Is Nothing
        ' Copy the raster and set the target gen to -1 (received).
        Dim featureBuffer As IFeatureBuffer = targetFeatureClass.CreateFeatureBuffer()
        featureBuffer.Value(targetRasterCatalog.RasterFieldIndex) = sourceFeature.Value(sourceRasterCatalog.RasterFieldIndex)
        featureBuffer.Value(targetGenFieldIndex) = -1
        targetCursor.InsertFeature(featureBuffer)

        ' Set the source row value to the current generation.
        If sourceFeature.Value(sourceGenFieldIndex).Equals(DBNull.Value) Then
          sourceFeature.Value(sourceGenFieldIndex) = genEnd
        End If
        sourceFeature.Store()
        sourceFeature = sourceCursor.NextFeature()
      End While
      Marshal.FinalReleaseComObject(sourceCursor)
      Marshal.FinalReleaseComObject(targetCursor)
    End If
  End Sub

  ''' <summary>
  ''' Occurs in the replica geodatabase before data changes are exported from that replica geodatabase to a delta database.
  ''' Not used in this implementation.
  ''' </summary>
  Public Sub BeforeExportingDataChanges(ByVal sourceReplica As IReplica, ByVal dataChangesSource As Object, ByVal deltaFile As Object) _
   Implements IWorkspaceReplicaSyncEvents.BeforeExportingDataChanges
    ' Not used in this implementation.
  End Sub

  ''' <summary>
  ''' Occurs in the master geodatabase before data changes in either a replica geodatabase or delta
  ''' database are transferred to the master geodatabase.
  ''' Not used in this implementation.
  ''' </summary>
  Public Sub BeforeSynchronizingDataChanges(ByVal targetReplica As IReplica, ByVal dataChangesSource As Object) _
  Implements IWorkspaceReplicaSyncEvents.BeforeSynchronizingDataChanges
    ' Not used in this implementation.
  End Sub
#End Region

End Class