/**
    * This file Copyright (c) 2010-2014 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.ui.vaadin.gwt.client.tabsheet.widget;
  
  import info.magnolia.ui.vaadin.gwt.client.tabsheet.event.ActiveTabChangedEvent;
  import info.magnolia.ui.vaadin.gwt.client.tabsheet.event.ShowAllTabsEvent;
  import info.magnolia.ui.vaadin.gwt.client.tabsheet.event.ShowAllTabsHandler;
  import info.magnolia.ui.vaadin.gwt.client.tabsheet.event.TabCloseEvent;
  import info.magnolia.ui.vaadin.gwt.client.tabsheet.event.TabCloseEventHandler;
  import info.magnolia.ui.vaadin.gwt.client.tabsheet.tab.widget.MagnoliaTabLabel;
  import info.magnolia.ui.vaadin.gwt.client.tabsheet.tab.widget.MagnoliaTabWidget;
  import info.magnolia.ui.vaadin.gwt.client.tabsheet.util.CollectionUtil;
  
  import java.util.LinkedList;
  import java.util.List;
  
  import com.google.gwt.event.dom.client.ClickEvent;
  import com.google.gwt.event.dom.client.ClickHandler;
  import com.google.gwt.user.client.DOM;
  import com.google.gwt.user.client.Element;
  import com.google.gwt.user.client.ui.ComplexPanel;
  import com.google.gwt.user.client.ui.SimplePanel;
  import com.google.web.bindery.event.shared.EventBus;
  
  /**
   * A bar that contains the tab labels and controls the switching between tabs.
   */
  public class TabBarWidget extends ComplexPanel {
  
      private static final String SINGLE_TAB_CLASS_NAME = "single-tab";
  
      private final List<MagnoliaTabLabel> tabLabels = new LinkedList<MagnoliaTabLabel>();
  
      private final Element tabContainer = DOM.createElement("ul");
  
      private EventBus eventBus;
  
      private VShellShowAllTabLabel showAllTab;
  
      public TabBarWidget(EventBus eventBus) {
          this.eventBus = eventBus;
          setElement(tabContainer);
          setStyleName("nav");
          addStyleDependentName("tabs");
      }
  
      @Override
      protected void onLoad() {
          super.onLoad();
          bindHandlers();
      }
  
      private void bindHandlers() {
          eventBus.addHandler(ActiveTabChangedEvent.TYPE, new ActiveTabChangedEvent.Handler() {
              @Override
              public void onActiveTabChanged(final ActiveTabChangedEvent event) {
                  final MagnoliaTabWidget tab = event.getTab();
                  final MagnoliaTabLabel label = tab.getLabel();
                  if (label != null) {
                      for (final MagnoliaTabLabel tabLabel : tabLabels) {
                          tabLabel.removeStyleName("active");
                      }
                      label.addStyleName("active");
                      showAll(false);
                  }
              }
          });
  
         eventBus.addHandler(TabCloseEvent.TYPE, new TabCloseEventHandler() {
             @Override
             public void onTabClosed(TabCloseEvent event) {
                 final MagnoliaTabLabel tabLabel = event.getTab().getLabel();
                 boolean wasActive = tabLabel.getStyleName().contains("active");
                 if (wasActive) {
                     final MagnoliaTabLabel nextLabel = getNextLabel(tabLabel);
                     if (nextLabel != null) {
                         nextLabel.addStyleName("active");
                     }
                 }
                 tabLabels.remove(tabLabel);
                 remove(tabLabel);
                 updateSingleTabStyle();
             }
         });
 
         eventBus.addHandler(ShowAllTabsEvent.TYPE, new ShowAllTabsHandler() {
 
             @Override
             public void onShowAllTabs(ShowAllTabsEvent event) {
                 for (final MagnoliaTabLabel tabLabel : tabLabels) {
                     tabLabel.removeStyleName("active");
                 }
                 showAll(true);
             }
         });
     }
 
     protected MagnoliaTabLabel getNextLabel(final MagnoliaTabLabel label) {
         return CollectionUtil.getNext(tabLabels, label);
     }
 
     public void addTabLabel(MagnoliaTabLabel label) {
         label.setEventBus(eventBus);
         if (!tabLabels.contains(label)) {
             tabLabels.add(label);
             add(label, getElement());
             updateSingleTabStyle();
         }
     }
 
     public void updateSingleTabStyle() {
         if (tabLabels.size() <= 1) {
             tabContainer.addClassName(SINGLE_TAB_CLASS_NAME);
         } else {
             tabContainer.removeClassName(SINGLE_TAB_CLASS_NAME);
         }
     }
 
     public void addShowAllTab(boolean showAll, String label) {
         if (showAll && showAllTab == null) {
             showAllTab = new VShellShowAllTabLabel(label);
             add(showAllTab, getElement());
         } else if (!showAll && showAllTab != null) {
             remove(showAllTab);
             showAllTab = null;
         }
     }
 
     private class VShellShowAllTabLabel extends SimplePanel {
 
         private final Element text = DOM.createSpan();
 
         public VShellShowAllTabLabel(String label) {
             super(DOM.createElement("li"));
             addStyleName("show-all");
             text.setInnerHTML(label);
             text.setClassName("tab-title");
             getElement().appendChild(text);
 
         }
 
         @Override
         protected void onLoad() {
             super.onLoad();
             bindHandlers();
         }
 
         private void bindHandlers() {
             addDomHandler(new ClickHandler() {
                 @Override
                 public void onClick(ClickEvent event) {
                     eventBus.fireEvent(new ShowAllTabsEvent());
                 }
             }, ClickEvent.getType());
         }
 
     }
 
     public void showAll(boolean showAll) {
         if (showAllTab != null) {
             if (showAll) {
                 showAllTab.addStyleName("active");
             } else {
                 if (showAllTab.getStyleName().contains("active")) {
                     showAllTab.removeStyleName("active");
                 }
             }
         }
     }
 
 }