// 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.
// 

using System;
using ESRI.ArcGIS.Analyst3D;
using ESRI.ArcGIS.Geometry;
using ESRI.ArcGIS.Controls;
using ESRI.ArcGIS.ADF.BaseClasses;
using ESRI.ArcGIS.ADF.CATIDs;
using System.Runtime.InteropServices;

namespace sceneTools
{
  [ClassInterface(ClassInterfaceType.None)]
  [Guid("834AC707-0088-4d08-BF74-A18EE28BCA8E")]

  public sealed class SetObserver : BaseTool
  {

        #region COM Registration Function(s)
        [ComRegisterFunction()]
        [ComVisible(false)]
        static void RegisterFunction(Type registerType)
        {
            // Required for ArcGIS Component Category Registrar support
            ArcGISCategoryRegistration(registerType);

            //
            // TODO: Add any COM registration code here
            //
        }

        [ComUnregisterFunction()]
        [ComVisible(false)]
        static void UnregisterFunction(Type registerType)
        {
            // Required for ArcGIS Component Category Registrar support
            ArcGISCategoryUnregistration(registerType);

            //
            // TODO: Add any COM unregistration code here
            //
        }

        #region ArcGIS Component Category Registrar generated code
        /// <summary>
        /// Required method for ArcGIS Component Category registration -
        /// Do not modify the contents of this method with the code editor.
        /// </summary>
        private static void ArcGISCategoryRegistration(Type registerType)
        {
            string regKey = string.Format("HKEY_CLASSES_ROOT\\CLSID\\{{{0}}}", registerType.GUID);
            ControlsCommands.Register(regKey);

        }
        /// <summary>
        /// Required method for ArcGIS Component Category unregistration -
        /// Do not modify the contents of this method with the code editor.
        /// </summary>
        private static void ArcGISCategoryUnregistration(Type registerType)
        {
            string regKey = string.Format("HKEY_CLASSES_ROOT\\CLSID\\{{{0}}}", registerType.GUID);
            ControlsCommands.Unregister(regKey);

        }

        #endregion
        #endregion

    private System.Windows.Forms.Cursor m_pCursor;
    private ISceneHookHelper m_pSceneHookHelper;

    public SetObserver()
    {
      base.m_category = "Sample_SceneControl(C#)";
      base.m_caption = "Set Observer";
      base.m_toolTip = "Set Observer";
      base.m_name = "Sample_SceneControl(C#)/SetObserver";
      base.m_message = "Set observer position to selected point";

      //Load resources
      string[] res = GetType().Assembly.GetManifestResourceNames();
      if(res.GetLength(0) > 0)
      {
        base.m_bitmap = new System.Drawing.Bitmap(GetType().Assembly.GetManifestResourceStream("sceneTools.observer.bmp"));
      }
      m_pCursor = new System.Windows.Forms.Cursor(GetType().Assembly.GetManifestResourceStream("sceneTools.observer.cur"));
    
      m_pSceneHookHelper = new SceneHookHelperClass ();
    }

    public override bool Enabled
    {
      get
      {
        if(m_pSceneHookHelper.Hook == null || m_pSceneHookHelper.Scene == null)
          return false;
        else
        {
          ICamera pCamera = (ICamera) m_pSceneHookHelper.Camera;

          //Disable if orthographic (2D) view
          if(pCamera.ProjectionType == esri3DProjectionType.esriOrthoProjection)
            return false;
          else
            return true;
        }
      }
    }
  
    public override void OnCreate(object hook)
    {
      m_pSceneHookHelper.Hook = hook;        
    }
  
    public override int Cursor
    {
      get
      {
        return m_pCursor.Handle.ToInt32();
      }
    }
  
    public override bool Deactivate()
    {
      return true;
    }
  
    public override void OnMouseUp(int Button, int Shift, int X, int Y)
    {
      //Get the scene graph
      ISceneGraph pSceneGraph = (ISceneGraph) m_pSceneHookHelper.SceneGraph;

      IPoint pNewObs;
      object pOwner, pObject;

      //Translate screen coordinates into a 3D point
      pSceneGraph.Locate(pSceneGraph.ActiveViewer, X, Y, esriScenePickMode.esriScenePickAll, true,
        out pNewObs, out pOwner, out pObject);

      if(pNewObs == null) return;

      //Get the scene viewer's camera
      ICamera pCamera = (ICamera) m_pSceneHookHelper.Camera;

      //Get the camera's old observer
      IPoint pOldObs = (IPoint) pCamera.Observer;

      //Get the duration in seconds of last redraw
      //and the average number of frames per second
      double dlastFrameDuration, dMeanFrameRate;
      pSceneGraph.GetDrawingTimeInfo(out dlastFrameDuration, out dMeanFrameRate);

      if(dlastFrameDuration < 0.01)
        dlastFrameDuration = 0.01;

      int iSteps;
      iSteps = (int) (2/dlastFrameDuration);
      if (iSteps < 1)
        iSteps = 1;
      
      if(iSteps > 60)
        iSteps = 60;

      double dxObs, dyObs, dzObs;

      dxObs = (pNewObs.X - pOldObs.X) / iSteps;
      dyObs = (pNewObs.Y - pOldObs.Y) / iSteps;
      dzObs = (pNewObs.Z - pOldObs.Z) / iSteps;

      //Loop through each step moving the camera's observer from the old
      //position to the new position, refreshing the scene viewer each time
      for(int i=0; i <= iSteps; i++)
      {
        pNewObs.X = pOldObs.X + (i * dxObs);
        pNewObs.Y = pOldObs.Y + (i * dyObs);
        pNewObs.Z = pOldObs.Z + (i * dzObs);
        pCamera.Observer = pNewObs;
        pSceneGraph.ActiveViewer.Redraw(true);
      }      
    }
  }
}