/**
    * This file Copyright (c) 2018 Magnolia International
    * Ltd.  (http://www.magnolia-cms.com). All rights reserved.
    *
    *
    * This file is dual-licensed under both the Magnolia
    * Network Agreement and the GNU General Public License.
    * You may elect to use one or the other of these licenses.
    *
   * This file is distributed in the hope that it will be
   * useful, but AS-IS and WITHOUT ANY WARRANTY; without even the
   * implied warranty of MERCHANTABILITY or FITNESS FOR A
   * PARTICULAR PURPOSE, TITLE, or NONINFRINGEMENT.
   * Redistribution, except as permitted by whichever of the GPL
   * or MNA you select, is prohibited.
   *
   * 1. For the GPL license (GPL), you can redistribute and/or
   * modify this file under the terms of the GNU General
   * Public License, Version 3, as published by the Free Software
   * Foundation.  You should have received a copy of the GNU
   * General Public License, Version 3 along with this program;
   * if not, write to the Free Software Foundation, Inc., 51
   * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
   *
   * 2. For the Magnolia Network Agreement (MNA), this file
   * and the accompanying materials are made available under the
   * terms of the MNA which accompanies this distribution, and
   * is available at http://www.magnolia-cms.com/mna.html
   *
   * Any modifications to this file must keep this entire header
   * intact.
   *
   */
  package info.magnolia.poc.extensions.client;
  
  import info.magnolia.poc.extensions.StringFieldValidationExtension;
  
  import com.google.gwt.dom.client.Element;
  import com.google.gwt.dom.client.Style;
  import com.google.gwt.user.client.DOM;
  import com.google.gwt.user.client.Event;
  import com.google.gwt.user.client.ui.Widget;
  import com.vaadin.client.ComponentConnector;
  import com.vaadin.client.ServerConnector;
  import com.vaadin.client.communication.StateChangeEvent;
  import com.vaadin.client.extensions.AbstractExtensionConnector;
  import com.vaadin.shared.AbstractComponentState;
  import com.vaadin.shared.ui.Connect;
  
  @Connect(StringFieldValidationExtension.class)
  public class StringFieldValidationExtensionConnector extends AbstractExtensionConnector {
  
      @Override
      protected void extend(ServerConnector target) {
          final ComponentConnector componentConnector = ((ComponentConnector) target);
          Element div = DOM.createDiv();
          DOM.sinkEvents(div, Event.ONCLICK | Event.ONFOCUS);
          DOM.setEventListener(div, event -> {
              div.getStyle().setDisplay(Style.Display.NONE);
          });
          StateChangeEvent.StateChangeHandler handler = (StateChangeEvent.StateChangeHandler) stateChangeEvent -> {
              AbstractComponentState state = (AbstractComponentState) target.getState();
              final Widget widget = componentConnector.getWidget();
              final Element containerElement = DOM.getParent(widget.getElement()).getParentElement();
              final Element labelDiv = containerElement.getFirstChildElement();
              if (state.errorMessage == null || state.errorMessage.isEmpty()) {
                  DOM.getParent(widget.getElement()).removeChild(div);
                  labelDiv.getFirstChildElement().removeClassName("v-caption-error");
              } else {
                  div.getStyle().setDisplay(Style.Display.BLOCK);
                  div.setInnerHTML(getValidationHtml(componentConnector.getState().errorMessage));
                  DOM.getParent(widget.getElement()).appendChild(div);
                  labelDiv.getFirstChildElement().addClassName("v-caption-error");
              }
          };
          componentConnector.addStateChangeHandler("errorMessage", handler);
  
      }
  
      private String getValidationHtml(String errorMessages) {
          return "<div class='validation-display'>" + errorMessages + "</div>";
      }
  
  
  }