' 
' (C) Copyright 2003-2019 by Autodesk, Inc.
' 
' Permission to use, copy, modify, and distribute this software in
' object code form for any purpose and without fee is hereby granted,
' provided that the above copyright notice appears in all copies and
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' DOES NOT WARRANT THAT THE OPERATION OF THE PROGRAM WILL BE
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' restrictions set forth in FAR 52.227-19 (Commercial Computer
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'

Imports System
Imports System.Collections.Generic

Imports Autodesk.Revit
Imports Autodesk.Revit.DB
Imports Autodesk.Revit.UI

''' <summary>
''' Implements the Revit add-in interface IExternalCommand
''' </summary>
''' <remarks></remarks>
<Autodesk.Revit.Attributes.Transaction(Autodesk.Revit.Attributes.TransactionMode.Manual)> _
<Autodesk.Revit.Attributes.Regeneration(Autodesk.Revit.Attributes.RegenerationOption.Manual)> _
<Autodesk.Revit.Attributes.Journaling(Autodesk.Revit.Attributes.JournalingMode.NoCommandData)> _
Public Class AnalyticalViewer
   Implements Autodesk.Revit.UI.IExternalCommand

   Private mViewer As RevitViewer.VB.NET.Wireframe
   Private mApplication As Autodesk.Revit.ApplicationServices.Application

   ''' <summary>
   ''' Implement this method as an external command for Revit.
   ''' </summary>
   ''' <param name="commandData">An object that is passed to the external application 
   ''' which contains data related to the command, 
   ''' such as the application object and active view.</param>
   ''' <param name="message">A message that can be set by the external application 
   ''' which will be displayed if a failure or cancellation is returned by 
   ''' the external command.</param>
   ''' <param name="elements">A set of elements to which the external application 
   ''' can add elements that are to be highlighted in case of failure or cancellation.</param>
   ''' <returns>Return the status of the external command. 
   ''' A result of Succeeded means that the API external method functioned as expected. 
   ''' Cancelled can be used to signify that the user cancelled the external operation 
   ''' at some point. Failure should be returned if the application is unable to proceed with 
   ''' the operation.</returns>
   Public Function Execute(ByVal commandData As ExternalCommandData, ByRef message As String, ByVal elements As Autodesk.Revit.DB.ElementSet) As Autodesk.Revit.UI.Result Implements IExternalCommand.Execute

      Dim element As Autodesk.Revit.DB.Element
      Dim elementId As Autodesk.Revit.DB.ElementId

      mApplication = commandData.Application.Application

      If (commandData.Application.ActiveUIDocument.Selection.GetElementIds().Count > 0) Then
         For Each elementId In commandData.Application.ActiveUIDocument.Selection.GetElementIds()
            element = commandData.Application.ActiveUIDocument.Document.GetElement(elementId)
            DrawAnalyticalModel(element)
         Next
      Else
         'ElementIsElementTypeFilter filter the elementType which has not AnalyticalModel
         Dim filter As Autodesk.Revit.DB.ElementIsElementTypeFilter
         filter = New Autodesk.Revit.DB.ElementIsElementTypeFilter(True)
         Dim collector As Autodesk.Revit.DB.FilteredElementCollector
         collector = New Autodesk.Revit.DB.FilteredElementCollector(commandData.Application.ActiveUIDocument.Document)
         collector.WherePasses(filter)
         Dim iter As IEnumerator
         iter = collector.GetElementIterator

         Do While (iter.MoveNext())
            element = iter.Current
            DrawAnalyticalModel(element)
         Loop
      End If

      If Not (mViewer Is Nothing) Then

         mViewer.Fit()
         mViewer.Draw()
         mViewer.ShowModal()
      Else
            TaskDialog.Show("Revit", "No analytical model to represent.")
      End If

      mViewer = Nothing
      mApplication = Nothing

      Return Autodesk.Revit.UI.Result.Succeeded
   End Function

   ''' <summary>
   ''' distribute analytical model to its corresponding method to be draw.
   ''' </summary>
   ''' <param name="element"></param>
   ''' <remarks></remarks>
   Private Sub DrawAnalyticalModel(ByVal element As Autodesk.Revit.DB.Element)

      Dim analyticalModel As Autodesk.Revit.DB.Structure.AnalyticalModel = Nothing

      analyticalModel = element.GetAnalyticalModel()

      If (analyticalModel Is Nothing) Then
         Exit Sub
      End If

      If (mViewer Is Nothing) Then
         mViewer = New RevitViewer.VB.NET.Wireframe
      End If

      If TypeOf element Is Autodesk.Revit.DB.FamilyInstance Then
         Dim familyInstance As Autodesk.Revit.DB.FamilyInstance = element

         If familyInstance.StructuralType.Equals(Autodesk.Revit.DB.Structure.StructuralType.Footing) Then
            DrawAnalyticalModelLocation(analyticalModel)
            Return
         End If

      End If

      DrawAnalyticalModelCurves(analyticalModel.GetCurves([Structure].AnalyticalCurveType.ActiveCurves))


   End Sub

   ''' <summary>
   ''' Draw the primitive curve.
   ''' </summary>
   ''' <param name="curve"></param>
   ''' <remarks></remarks>
   Private Sub DrawAnalyticalModelCurve(ByVal curve As Autodesk.Revit.DB.Curve)

      If (curve Is Nothing) Then
         Exit Sub
      End If

      Dim points As New List(Of Autodesk.Revit.DB.XYZ)
      points = curve.Tessellate

      If (points Is Nothing) Then
         Exit Sub
      End If

      If points.Count = 0 Then
         Exit Sub
      End If

      Dim previousPoint As Autodesk.Revit.DB.XYZ
      previousPoint = New Autodesk.Revit.DB.XYZ
      Dim i As Integer
      For i = 0 To points.Count - 1

         Dim point As Autodesk.Revit.DB.XYZ
         point = points.Item(i)
         If i > 0 Then
            mViewer.Add(previousPoint.X, previousPoint.Y, previousPoint.Z, point.X, point.Y, point.Z)
         End If

         previousPoint = point
      Next

   End Sub

   ''' <summary>
   ''' Draw the primitive curve array.
   ''' </summary>
   ''' <param name="curves"></param>
   ''' <remarks></remarks>
   Private Sub DrawAnalyticalModelCurves(ByVal curves As IList(Of Curve))

      Dim curve As Autodesk.Revit.DB.Curve

      For Each curve In curves

         DrawAnalyticalModelCurve(curve)

      Next

   End Sub


   ''' <summary>
   ''' draw analytical location model
   ''' </summary>
   ''' <param name="analyticalModel"></param>
   ''' <remarks></remarks>
   Private Sub DrawAnalyticalModelLocation(ByVal analyticalModel As Autodesk.Revit.DB.Structure.AnalyticalModel)

      'draw a square

      Dim location As Autodesk.Revit.DB.XYZ
      location = analyticalModel.GetPoint()

      Dim curves As IList(Of Curve) = New List(Of Curve)()

      Dim point1 As Autodesk.Revit.DB.XYZ
      point1 = New Autodesk.Revit.DB.XYZ
      Dim point2 As Autodesk.Revit.DB.XYZ
      point2 = New Autodesk.Revit.DB.XYZ
      Dim point3 As Autodesk.Revit.DB.XYZ
      point3 = New Autodesk.Revit.DB.XYZ
      Dim point4 As Autodesk.Revit.DB.XYZ
      point4 = New Autodesk.Revit.DB.XYZ

      point1 = New Autodesk.Revit.DB.XYZ(location.X - 2, location.Y - 2, location.Z)

      point2 = New Autodesk.Revit.DB.XYZ(location.X - 2, location.Y + 2, location.Z)

      point3 = New Autodesk.Revit.DB.XYZ(location.X + 2, location.Y + 2, location.Z)

      point4 = New Autodesk.Revit.DB.XYZ(location.X + 2, location.Y - 2, location.Z)

      Dim line1 As Autodesk.Revit.DB.Line
      Dim line2 As Autodesk.Revit.DB.Line
      Dim line3 As Autodesk.Revit.DB.Line
      Dim line4 As Autodesk.Revit.DB.Line

      line1 = Autodesk.Revit.DB.Line.CreateBound(point1, point2)
      line2 = Autodesk.Revit.DB.Line.CreateBound(point2, point3)
      line3 = Autodesk.Revit.DB.Line.CreateBound(point3, point4)
      line4 = Autodesk.Revit.DB.Line.CreateBound(point4, point1)

      curves.Add(line1)
      curves.Add(line2)
      curves.Add(line3)
      curves.Add(line4)

      DrawAnalyticalModelCurves(curves)

   End Sub

End Class