// Copyright 2010 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.
// 

// Illustrates how to remove an existing layer in a pooled ArcGIS Server map service using Web ADF components
// and ArcObjects. For illustration of how to add and remove a dynamic layer from a map service, see the 
// Default_ADF and CustomMapHandler_ADF pages. Note that this code bypasses use of the custom map handler (and
// the accompanying increase in map performance) by setting the Map1.EnableMapHandler property to false.
public partial class RemoveLayer_ADF : System.Web.UI.Page
{
    #region Instance Variable Declarations

    private ServerObjectStateModifier _serverObjectStateModifier = null;
    private System.Collections.Generic.Dictionary<int, ESRI.ArcGIS.Carto.ILayer> _removedLayerDictionary = null;
    
    // Specify the name of the resource containing the layer to remove
    private string _targetResourceName = "MapResourceItem0";
    // Specify the name of the layer to remove
    private string _targetLayerName = "Highways";

    #endregion

    #region ASP.NET Page Life Cycle Event Handlers

    protected void Page_PreInit(object sender, System.EventArgs e)
    {
        // Instantiate a class-level ServerObjectStateModifier to use in removing and re-adding the layer
        _serverObjectStateModifier = new ServerObjectStateModifier();
    }

    protected void Page_Load(object sender, System.EventArgs e)
    {
        try
        {
            // Register the remover layer button so it initiates an asynchronous
            // postback when clicked
            ScriptManager1.RegisterAsyncPostBackControl(RemoveLayerButton);

            // If the target layer has been removed (indicated by the session variable), then we need to re-remove it
            // so that the Web ADF components accessing the changed map resource is aware of the change.  
            if ((Session["LayerRemoved"] != null) && ((bool)Session["LayerRemoved"]))
            {
                // Get the layer's target resource and call the method to remove the layer from it
                ESRI.ArcGIS.ADF.Web.DataSources.ArcGISServer.MapFunctionality agsMapFunctionality =
                    (ESRI.ArcGIS.ADF.Web.DataSources.ArcGISServer.MapFunctionality)Map1.GetFunctionality(_targetResourceName);
                ESRI.ArcGIS.ADF.Web.DataSources.ArcGISServer.MapResourceLocal mapResourceLocal =
                    (ESRI.ArcGIS.ADF.Web.DataSources.ArcGISServer.MapResourceLocal)agsMapFunctionality.Resource;
                _removedLayerDictionary = _serverObjectStateModifier.RemoveLayer(mapResourceLocal, _targetLayerName);
            }

            MapResourceManager1.ResourcesDispose += new System.EventHandler(MapResourceManager1_ResourcesDispose);
        }
        catch (System.Exception exception)
        {
            // Check whether the page is loading asynchronously
            if (ScriptManager1.IsInAsyncPostBack)
            {
                // Get a callback result that will show an alert with information pertaining to the exception
                ESRI.ArcGIS.ADF.Web.UI.WebControls.CallbackResult errorCallbackResult =
                    Utility.GetErrorCallback(exception);
                // Get the control that initiated the postback
                System.Web.UI.Control control = Utility.GetPostBackControl(Page);

                // If the control is a Web ADF Control (i.e. WebCotnrol or CompositeControl), add the error 
                // callback to that control's callback results.  Otherwise, add the error callback to the 
                // callback results collection member variable, which will be passed to the client in 
                // GetCallbackResult.
                if (control is ESRI.ArcGIS.ADF.Web.UI.WebControls.WebControl)
                {
                    ESRI.ArcGIS.ADF.Web.UI.WebControls.WebControl adfWebControl = control as
                        ESRI.ArcGIS.ADF.Web.UI.WebControls.WebControl;
                    adfWebControl.CallbackResults.Add(errorCallbackResult);
                }
                else if (control is ESRI.ArcGIS.ADF.Web.UI.WebControls.CompositeControl)
                {
                    ESRI.ArcGIS.ADF.Web.UI.WebControls.CompositeControl adfCompositeControl = control as
                        ESRI.ArcGIS.ADF.Web.UI.WebControls.CompositeControl;
                    adfCompositeControl.CallbackResults.Add(errorCallbackResult);
                }
                else
                {
          ESRI.ArcGIS.ADF.Web.UI.WebControls.CallbackResultCollection callbackResults =
            new ESRI.ArcGIS.ADF.Web.UI.WebControls.CallbackResultCollection();
          callbackResults.Add(errorCallbackResult);
          ScriptManager1.RegisterDataItem(Page, callbackResults.ToString(), false);
                }
            }
            else
            {
                // Since the page is in full postback, write the javascript alert code directly to the response
                string jsErrorAlert = string.Format("<script>{0}</script>",
                    Utility.GetJavaScriptErrorString(exception));
                Response.Write(jsErrorAlert);
            }
        }
    }

    #endregion

    #region Web ADF Control Event Handlers

    void MapResourceManager1_ResourcesDispose(object sender, System.EventArgs e)
    {
        // If the target layer has been removed (indicated by the session variable), then we need to add it back to the resource
        // before the server context created as a result of the current page request is released.  Otherwise, the target layer 
        // will be missing from the map service outside the scope of this request, so other clients using the service will not have
        // access to it.
        if ((Session["LayerRemoved"] != null) && ((bool)Session["LayerRemoved"]))
        {
            // Get the resource from which the layer was removed
            ESRI.ArcGIS.ADF.Web.DataSources.ArcGISServer.MapFunctionality agsMapFunctionality =
                (ESRI.ArcGIS.ADF.Web.DataSources.ArcGISServer.MapFunctionality)Map1.GetFunctionality(_targetResourceName);
            ESRI.ArcGIS.ADF.Web.DataSources.ArcGISServer.MapResourceLocal mapResourceLocal =
                (ESRI.ArcGIS.ADF.Web.DataSources.ArcGISServer.MapResourceLocal)agsMapFunctionality.Resource;

            // Retrieve a reference to the missing layer and its original layer index from the class-level dictionary that
            // stored this information when the layer was removed
            System.Collections.Generic.Dictionary<int, ESRI.ArcGIS.Carto.ILayer>.Enumerator removedLayerEnumerator = 
                _removedLayerDictionary.GetEnumerator();
            removedLayerEnumerator.MoveNext();
            ESRI.ArcGIS.Carto.IGeoFeatureLayer removedGeoFeatureLayer = removedLayerEnumerator.Current.Value as
                ESRI.ArcGIS.Carto.IGeoFeatureLayer;
            int layerIndex = removedLayerEnumerator.Current.Key;
            
            // Add the layer back to the map service
            _serverObjectStateModifier.AddLayer(mapResourceLocal, removedGeoFeatureLayer, layerIndex);
        }
    }

    #endregion

    #region ASP.NET Web Control Event Handlers

  public void RemoveLayerButton_Click(object sender, System.EventArgs e)
  {
    try
    {
      Session["LayerRemoved"] = true;

      // Get the layer's target resource and call the method to remove the layer from it
      ESRI.ArcGIS.ADF.Web.DataSources.ArcGISServer.MapFunctionality agsMapFunctionality =
        (ESRI.ArcGIS.ADF.Web.DataSources.ArcGISServer.MapFunctionality)Map1.GetFunctionality(_targetResourceName);
      ESRI.ArcGIS.ADF.Web.DataSources.ArcGISServer.MapResourceLocal mapResourceLocal =
        (ESRI.ArcGIS.ADF.Web.DataSources.ArcGISServer.MapResourceLocal)agsMapFunctionality.Resource;

      // Store a reference to the dictionary containing the layer and its index in the map service
      _removedLayerDictionary = _serverObjectStateModifier.RemoveLayer(mapResourceLocal, _targetLayerName);

      // Refresh the Map and Toc so they reflect the layer's removal
      RefreshMapAndToc();
    }
    catch (System.Exception exception)
    {
      // Get a callback result that will alert the user of the error and add it to the callback results collection
      ESRI.ArcGIS.ADF.Web.UI.WebControls.CallbackResult errorCallbackResult =
        Utility.GetErrorCallback(exception);
      ESRI.ArcGIS.ADF.Web.UI.WebControls.CallbackResultCollection callbackResults =
        new ESRI.ArcGIS.ADF.Web.UI.WebControls.CallbackResultCollection();
      callbackResults.Add(errorCallbackResult);
      ScriptManager1.RegisterDataItem(Page, callbackResults.ToString(), false);
    }
  }

    #endregion

    #region Instance Methods

    // Refreshes the Map and Toc controls and populates the callback results member variable with the
    // resulting callback results 
    private void RefreshMapAndToc()
    {
        Toc1.Refresh();
        Map1.CallbackResults.CopyFrom(Toc1.CallbackResults);

    Map1.RefreshResource(_targetResourceName);
    ESRI.ArcGIS.ADF.Web.UI.WebControls.CallbackResultCollection callbackResults =
      new ESRI.ArcGIS.ADF.Web.UI.WebControls.CallbackResultCollection();
    callbackResults.CopyFrom(Map1.CallbackResults);
    ScriptManager1.RegisterDataItem(Page, callbackResults.ToString(), false);
    }

    #endregion
}