/**
    * This file Copyright (c) 2011-2013 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.magnoliashell.shell;
  
  import info.magnolia.ui.vaadin.gwt.client.jquerywrapper.JQueryCallback;
  import info.magnolia.ui.vaadin.gwt.client.jquerywrapper.JQueryWrapper;
  import info.magnolia.ui.vaadin.gwt.client.magnoliashell.shellmessage.ShellMessageWidget;
  import info.magnolia.ui.vaadin.gwt.client.magnoliashell.shellmessage.ShellMessageWidget.MessageType;
  import info.magnolia.ui.vaadin.gwt.client.magnoliashell.shellmessage.VInfoMessage;
  import info.magnolia.ui.vaadin.gwt.client.magnoliashell.shellmessage.VShellErrorMessage;
  import info.magnolia.ui.vaadin.gwt.client.magnoliashell.shellmessage.VWarningMessage;
  import info.magnolia.ui.vaadin.gwt.client.magnoliashell.viewport.animation.JQueryAnimation;
  import info.magnolia.ui.vaadin.gwt.client.magnoliashell.viewport.widget.AppsViewportWidget;
  import info.magnolia.ui.vaadin.gwt.client.magnoliashell.viewport.widget.ViewportWidget;
  import info.magnolia.ui.vaadin.gwt.client.shared.magnoliashell.Fragment;
  import info.magnolia.ui.vaadin.gwt.client.shared.magnoliashell.ShellAppType;
  import info.magnolia.ui.vaadin.gwt.client.shared.magnoliashell.ViewportType;
  
  import java.util.EnumMap;
  import java.util.Map;
  
  import com.google.gwt.core.client.Scheduler;
  import com.google.gwt.core.client.Scheduler.ScheduledCommand;
  import com.google.gwt.event.dom.client.KeyCodes;
  import com.google.gwt.event.dom.client.KeyPressEvent;
  import com.google.gwt.event.dom.client.KeyPressHandler;
  import com.google.gwt.user.client.DOM;
  import com.google.gwt.user.client.Element;
  import com.google.gwt.user.client.ui.FocusPanel;
  import com.google.gwt.user.client.ui.RootPanel;
  import com.google.gwt.user.client.ui.Widget;
  import com.googlecode.mgwt.ui.client.widget.touch.TouchPanel;
  
  /**
   * GWT implementation of MagnoliaShell client side (the view part basically).
   */
  public class MagnoliaShellViewImpl extends TouchPanel implements MagnoliaShellView {
  
      public static final String CLASS_NAME = "v-magnolia-shell";
  
      public static final String VIEWPORT_SLOT_CLASS_NAME = "v-shell-viewport-slot";
  
      private final Map<ViewportType, ViewportWidget> viewports = new EnumMap<ViewportType, ViewportWidget>(ViewportType.class);
  
      private final ShellAppLauncher mainAppLauncher;
  
      private ShellMessageWidget lowPriorityMessage;
  
      private ShellMessageWidget hiPriorityMessage;
  
      private Presenter presenter;
  
      private JQueryAnimation viewportShifter = new JQueryAnimation();
  
      private final Element viewportSlot = DOM.createDiv();
  
      // To remove focus (blur) all input elements, one just needs to focus this element.
      private final FocusPanel blurHelper = new FocusPanel();
  
      public MagnoliaShellViewImpl() {
          super();
          this.mainAppLauncher = new ShellAppLauncher();
          getElement().setClassName(CLASS_NAME);
          viewportSlot.setClassName(VIEWPORT_SLOT_CLASS_NAME);
          add(mainAppLauncher, getElement());
  
  
          getElement().appendChild(viewportSlot);
         viewportShifter.addCallback(new JQueryCallback() {
             @Override
             public void execute(JQueryWrapper query) {
                 presenter.updateViewportLayout(appViewport());
             }
         });
 
         initKeyboardShortcutSupport();
     }
 
 
     /**
      * Bind keyboard handlers.
      * These commands are only processed if an input area does not have focus.
      */
     protected void initKeyboardShortcutSupport() {
 
         add(blurHelper, getElement());
 
         KeyPressHandler keyboardShortcutHandler = new KeyPressHandler() {
 
             @Override
             public void onKeyPress(KeyPressEvent event) {
 
                 // Only process keyboard shortcuts if user is not in an input field.
                 if (isFocusedElementAnInputField()) {
                     return;
                 }
 
                 // Only process if no modifier keys are held down to avoid collision with OS or Browser hotkeys.
                 if (event.isAnyModifierKeyDown()) {
                     return;
                 }
 
                 char c = event.getCharCode();
 
                 switch (c) {
 
                 // Shell Apps
                 case '1':
                     mainAppLauncher.toggleShellApp(ShellAppType.APPLAUNCHER);
                     break;
                 case '2':
                     mainAppLauncher.toggleShellApp(ShellAppType.PULSE);
                     break;
                 case '3':
                     mainAppLauncher.toggleShellApp(ShellAppType.FAVORITE);
                     break;
 
                 // App Stack Navigation.
                 case '9':
                     appViewport().goToPreviousApp();
                     break;
                 case '0':
                     appViewport().goToNextApp();
                     break;
 
                 default:
                     // Nothing
                 }
             }
         };
         RootPanel.get().addDomHandler(keyboardShortcutHandler, KeyPressEvent.getType());
 
 
         /**
          * Pressing the escape key causes all elements to loose focus.
          * This is a handy way to be able to start using the single-key keyboard shortcuts.
          */
         KeyPressHandler escapeKeyPressHandler = new KeyPressHandler() {
             @Override
             public void onKeyPress(KeyPressEvent event) {
                 int code = event.getNativeEvent().getKeyCode();
                 if (code == KeyCodes.KEY_ESCAPE) {
                     blurHelper.getElement().focus();
                 }
             }
         };
         RootPanel.get().addDomHandler(escapeKeyPressHandler, KeyPressEvent.getType());
     }
 
     /**
      * Returns whether the currently focused element is one that accepts keyboard input.
      * 
      * @return
      */
     protected boolean isFocusedElementAnInputField() {
         Element focused = elementInFocus(RootPanel.get().getElement());
         String tagName = focused.getTagName();
         if ("input".equalsIgnoreCase(tagName) || "select".equalsIgnoreCase(tagName) || "textarea".equalsIgnoreCase(tagName)) {
             return true;
         }
         return false;
     }
 
     protected native Element elementInFocus(Element element) /*-{
                                                              return element.ownerDocument.activeElement;
                                                              }-*/;
 
 
     protected AppsViewportWidget appViewport() {
         return (AppsViewportWidget) viewports.get(ViewportType.APP);
     }
 
     protected void replaceWidget(final Widget oldWidget, final Widget newWidget) {
         if (oldWidget != newWidget) {
             if (oldWidget != null) {
                 remove(oldWidget);
             }
         }
         if (getWidgetIndex(newWidget) < 0) {
             add(newWidget, viewportSlot);
         }
     }
 
     @Override
     public void setPresenter(Presenter presenter) {
         this.presenter = presenter;
         mainAppLauncher.setListener(presenter);
     }
 
     @Override
     public void showMessage(MessageType type, String topic, String message, String id) {
         final ShellMessageWidget msg;
         switch (type) {
         case WARNING:
             msg = new VWarningMessage(this, topic, message, id);
             if (lowPriorityMessage != null && getWidgetIndex(lowPriorityMessage) != -1) {
                 lowPriorityMessage.hide();
             }
             lowPriorityMessage = msg;
             break;
         case INFO:
             msg = new VInfoMessage(this, topic, message, id);
             if (lowPriorityMessage != null && getWidgetIndex(lowPriorityMessage) != -1) {
                 lowPriorityMessage.hide();
             }
             lowPriorityMessage = msg;
             break;
         case ERROR:
             msg = new VShellErrorMessage(this, topic, message, id);
             if (hiPriorityMessage != null && getWidgetIndex(hiPriorityMessage) != -1) {
                 hiPriorityMessage.hide();
             }
             hiPriorityMessage = msg;
             break;
         default:
             msg = null;
         }
         Scheduler.get().scheduleDeferred(new ScheduledCommand() {
 
             @Override
             public void execute() {
                 if (msg != null) {
                     add(msg, getElement());
                 }
             }
         });
     }
 
     @Override
     public void hideAllMessages() {
         if (hiPriorityMessage != null && getWidgetIndex(hiPriorityMessage) != -1) {
             hiPriorityMessage.hideWithoutTransition();
         }
         if (lowPriorityMessage != null && getWidgetIndex(lowPriorityMessage) != -1) {
             lowPriorityMessage.hideWithoutTransition();
         }
 
         hiPriorityMessage = null;
         lowPriorityMessage = null;
     }
 
     @Override
     public void updateViewport(ViewportWidget viewport, ViewportType type) {
         ViewportWidget oldViewport = viewports.get(type);
         if (oldViewport != viewport) {
             replaceWidget(oldViewport, viewport);
             viewports.put(type, viewport);
         }
     }
 
     @Override
     public void shiftViewportsVertically(int shiftPx, boolean animated) {
         viewportShifter.setProperty("top", mainAppLauncher.getOffsetHeight() + shiftPx);
         if (shiftPx == 0 || shiftPx == 60) {
             viewportShifter.clearTopAfterThisAnimation();
         }
         viewportShifter.run(animated ? 300 : 0, viewportSlot);
     }
 
     @Override
     public void setShellAppIndication(ShellAppType type, int indication) {
         mainAppLauncher.setIndication(type, indication);
     }
 
     @Override
     public void closeMessageEager(final String id) {
         presenter.removeMessage(id);
     }
 
     @Override
     public void navigateToMessageDetails(String id) {
         presenter.activateShellApp(Fragment.fromString("shell:pulse:messages/" + id));
     }
 
     @Override
     public void updateShellDivet() {
         mainAppLauncher.updateDivet();
     }
 
     @Override
     public void openOverlayOnWidget(Widget overlayWidget, Widget overlayParent) {
         add(overlayWidget, overlayParent.getElement());
     }
 
     @Override
     public void onShellAppStarting(ShellAppType type) {
         mainAppLauncher.activateControl(type);
     }
 
     @Override
     public void onAppStarting() {
         mainAppLauncher.deactivateControls();
     }
 
     @Override
     public void setUserMenu(Widget widget) {
         mainAppLauncher.setUserMenu(widget);
     }
 
     @Override
     public void onLoad() {
         super.onLoad();
         presenter.initHistory();
     }
 
     @Override
     public boolean hasOverlay(Widget widget) {
         return getWidgetIndex(widget) != -1;
     }
 
 
 }