Add FIELD Function, fix virtual columns

MultiTool.Shared/Templates/TemplateLoader.vb

@@ -240,9 +240,11 @@ Namespace Templates
                 Return pTemplate
             End If
 
-            For Each oTable In pTemplate.Tables
+            Dim oTemplate = CreateVirtualColumns(pTemplate, pTemplateConfig)
+
+            For Each oTable In oTemplate.Tables
                 For Each oColumn As Template.Column In oTable.Columns
-                    Dim oConfig = pTemplateConfig.GetColumn(oColumn.Name, oTable.Name)
+                    Dim oConfig As TemplateConfigItem = pTemplateConfig.GetColumn(oColumn.Name, oTable.Name)
 
                     If oConfig Is Nothing Then
                         oConfig = New TemplateConfigItem With {
@@ -255,6 +257,31 @@ Namespace Templates
                 Next
             Next
 
+            Return oTemplate
+        End Function
+
+        Private Function CreateVirtualColumns(pTemplate As Template, pTemplateConfig As TemplateConfig) As Template
+            For Each oConfigItem In pTemplateConfig.Items
+                ' Find the table that relates to this config item
+                Dim oTable = pTemplate.Tables.Where(Function(table) table.Name = oConfigItem.Table).FirstOrDefault()
+
+                If oTable Is Nothing Then
+                    Logger.Warn("Table [{0}] for item [{1}] does exist in this Template!", oConfigItem.Table, oConfigItem.Name)
+                    Continue For
+                End If
+
+                Dim oColumnExists = oTable.Columns.Any(Function(column) column.Name = oConfigItem.Name)
+
+                If oColumnExists = False And oConfigItem.IsVirtual = True Then
+                    oTable.Columns.Add(New Template.Column() With {
+                        .Name = oConfigItem.Name,
+                        .Config = oConfigItem,
+                        .DataType = Constants.ColumnType.String,
+                        .IsRequired = False
+                    })
+                End If
+            Next
+
             Return pTemplate
         End Function