/**
   * Create a {@link TiledImageLayer} layer described by an XML layer description.
   *
   * @param domElement the XML element describing the layer to create. The element must inculde a
   *     service name identifying the type of service to use to retrieve layer data. Recognized
   *     service types are "Offline", "WWTileService" and "OGC:WMS".
   * @param params any parameters to apply when creating the layer.
   * @return a new layer
   * @throws WWUnrecognizedException if the service type given in the describing element is
   *     unrecognized.
   */
  protected Layer createTiledImageLayer(Element domElement, AVList params) {
    Layer layer;

    String serviceName = WWXML.getText(domElement, "Service/@serviceName");

    if ("Offline".equals(serviceName)) {
      layer = new BasicTiledImageLayer(domElement, params);
    } else if ("WWTileService".equals(serviceName)) {
      layer = new BasicTiledImageLayer(domElement, params);
    } else if (OGCConstants.WMS_SERVICE_NAME.equals(serviceName)) {
      layer = new WMSTiledImageLayer(domElement, params);
    } else if (AVKey.SERVICE_NAME_LOCAL_RASTER_SERVER.equals(serviceName)) {
      layer = new LocalRasterServerLayer(domElement, params);
    } else {
      String msg = Logging.getMessage("generic.UnrecognizedServiceName", serviceName);
      throw new WWUnrecognizedException(msg);
    }
    //
    //        String name = layer.getStringValue(AVKey.DISPLAY_NAME);
    //        System.out.println(name);

    String actuate = WWXML.getText(domElement, "@actuate");
    layer.setEnabled(actuate != null && actuate.equals("onLoad"));

    return layer;
  }
  /**
   * Create a collection of layer lists and their included layers described by an array of XML
   * layer-list description elements.
   *
   * <p>Any exceptions occurring during creation of the layer lists or their included layers are
   * logged and not re-thrown. The layers associated with the exceptions are not included in the
   * returned layer list.
   *
   * @param elements the XML elements describing the layer lists to create.
   * @param params any parameters to apply when creating the included layers.
   * @return an array containing the specified layer lists.
   */
  protected LayerList[] createLayerLists(Element[] elements, AVList params) {
    ArrayList<LayerList> layerLists = new ArrayList<LayerList>();

    for (Element element : elements) {
      try {
        String href = WWXML.getText(element, "@href");
        if (href != null && href.length() > 0) {
          Object o = this.createFromConfigSource(href, params);
          if (o == null) continue;

          if (o instanceof Layer) {
            LayerList ll = new LayerList();
            ll.add((Layer) o);
            o = ll;
          }

          if (o instanceof LayerList) {
            LayerList list = (LayerList) o;
            if (list != null && list.size() > 0) layerLists.add(list);
          } else if (o instanceof LayerList[]) {
            LayerList[] lists = (LayerList[]) o;
            if (lists != null && lists.length > 0) layerLists.addAll(Arrays.asList(lists));
          } else {
            String msg =
                Logging.getMessage("LayerFactory.UnexpectedTypeForLayer", o.getClass().getName());
            Logging.logger().log(java.util.logging.Level.WARNING, msg);
          }

          continue;
        }

        String title = WWXML.getText(element, "@title");
        Element[] children = WWXML.getElements(element, "./Layer", null);
        if (children != null && children.length > 0) {
          LayerList list = this.createLayerList(children, params);
          if (list != null && list.size() > 0) {
            layerLists.add(list);
            if (title != null && title.length() > 0) list.setValue(AVKey.DISPLAY_NAME, title);
          }
        }
      } catch (Exception e) {
        Logging.logger().log(java.util.logging.Level.WARNING, e.getMessage(), e);
        // keep going to create other layers
      }
    }

    return layerLists.toArray(new LayerList[layerLists.size()]);
  }
  /**
   * Create the objects described in an XML element containing layer and/or layer-list descriptions.
   * Nested layer lists and included layers are created recursively.
   *
   * @param domElement an XML element describing the layers and/or layer lists.
   * @param params any properties to apply when creating the included layers.
   * @return a <code>Layer</code>, <code>LayerList</code> or array of <code>LayerList</code>s, as
   *     described by the specified description.
   * @throws Exception if an exception occurs during creation. Exceptions occurring during creation
   *     of internal layers or layer lists are not re-thrown but are logged. The layer or layer list
   *     associated with the exception is not contained in the returned object.
   */
  @Override
  protected Object doCreateFromElement(Element domElement, AVList params) throws Exception {
    Element[] elements = WWXML.getElements(domElement, "//LayerList", null);
    if (elements != null && elements.length > 0) return createLayerLists(elements, params);

    elements = WWXML.getElements(domElement, "./Layer", null);
    if (elements != null && elements.length > 1) return createLayerList(elements, params);

    if (elements != null && elements.length == 1)
      return this.createFromLayerDocument(elements[0], params);

    String localName = WWXML.getUnqualifiedName(domElement);
    if (localName != null && localName.equals("Layer"))
      return this.createFromLayerDocument(domElement, params);

    return null;
  }
  /**
   * Create a layer described by an XML layer description.
   *
   * @param domElement the XML element describing the layer to create.
   * @param params any parameters to apply when creating the layer.
   * @return a new layer
   * @throws WWUnrecognizedException if the layer type or service type given in the describing
   *     element is unrecognized.
   * @see #createTiledImageLayer(org.w3c.dom.Element, gov.nasa.worldwind.avlist.AVList).
   */
  protected Layer createFromLayerDocument(Element domElement, AVList params) {
    String className = WWXML.getText(domElement, "@className");
    if (className != null && className.length() > 0) {
      Layer layer = (Layer) WorldWind.createComponent(className);
      String actuate = WWXML.getText(domElement, "@actuate");
      layer.setEnabled(WWUtil.isEmpty(actuate) || actuate.equals("onLoad"));
      WWXML.invokePropertySetters(layer, domElement);
      return layer;
    }

    AVList props = WWXML.copyProperties(domElement, null);
    if (props != null) { // Copy params and add any properties for this layer to the copy
      if (params != null) props.setValues(params);
      params = props;
    }

    Layer layer;
    String href = WWXML.getText(domElement, "@href");
    if (href != null && href.length() > 0) {
      Object o = this.createFromConfigSource(href, params);
      if (o == null) return null;

      if (!(o instanceof Layer)) {
        String msg =
            Logging.getMessage("LayerFactory.UnexpectedTypeForLayer", o.getClass().getName());
        throw new WWRuntimeException(msg);
      }

      layer = (Layer) o;
    } else {
      String layerType = WWXML.getText(domElement, "@layerType");
      if (layerType != null && layerType.equals("TiledImageLayer")) {
        layer = this.createTiledImageLayer(domElement, params);
      } else {
        String msg = Logging.getMessage("generic.UnrecognizedLayerType", layerType);
        throw new WWUnrecognizedException(msg);
      }
    }

    if (layer != null) {
      String actuate = WWXML.getText(domElement, "@actuate");
      layer.setEnabled(actuate != null && actuate.equals("onLoad"));
      WWXML.invokePropertySetters(layer, domElement);
    }

    return layer;
  }