/**
    * This file Copyright (c) 2010-2015 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.form.formsection.widget;
  
  import info.magnolia.ui.vaadin.gwt.client.form.tab.widget.FormTabWidget;
  import info.magnolia.ui.vaadin.gwt.client.form.widget.FormFieldWrapper;
  import info.magnolia.ui.vaadin.gwt.client.jquerywrapper.AnimationSettings;
  import info.magnolia.ui.vaadin.gwt.client.jquerywrapper.JQueryCallback;
  import info.magnolia.ui.vaadin.gwt.client.jquerywrapper.JQueryWrapper;
  
  import java.util.ArrayList;
  import java.util.Iterator;
  import java.util.LinkedHashMap;
  import java.util.List;
  import java.util.Map;
  
  import com.google.gwt.user.client.DOM;
  import com.google.gwt.user.client.Element;
  import com.google.gwt.user.client.Timer;
  import com.google.gwt.user.client.ui.FlowPanel;
  import com.google.gwt.user.client.ui.Widget;
  
  /**
   * Layout for the {@link info.magnolia.ui.vaadin.gwt.client.form.widget.FormFieldWrapper} widgets.
   */
  public class FormSectionWidget extends FlowPanel {
  
      private final Map<Widget, FormFieldWrapper> sections = new LinkedHashMap<Widget, FormFieldWrapper>();
  
      private final Element fieldSet = DOM.createElement("fieldset");
  
      private final Element legend = DOM.createElement("legend");
  
      private final Element horizontalRule = DOM.createElement("hr");
  
      public FormSectionWidget() {
          super();
          getElement().appendChild(fieldSet);
          fieldSet.appendChild(legend);
          fieldSet.appendChild(horizontalRule);
      }
  
      @Override
      public void add(Widget child) {
          throw new UnsupportedOperationException();
      }
  
      @Override
      public boolean remove(Widget w) {
          FormFieldWrapper fieldSection = (w instanceof FormFieldWrapper) ? (FormFieldWrapper) w : sections.get(w);
          if (w != null) {
              sections.remove(w);
              super.remove(fieldSection);
          }
          return false;
      }
  
      @Override
      public void insert(Widget w, int beforeIndex) {
          if (sections.containsKey(w)) {
              return;
          }
          FormFieldWrapper fieldSection;
          if (!(w instanceof FormFieldWrapper)) {
              fieldSection = new FormFieldWrapper();
              sections.put(w, fieldSection);
              fieldSection.setField(w);
          } else {
             fieldSection = (FormFieldWrapper) w;
         }
 
         // Patch ComplexPanel's insert logic to keep 0 index for the legend element (element is appended in the constructor).
         // Although fieldset's legend is usually displayed on top of it regardless of its position in the DOM, this was not the case in older versions of Internet Explorer.
         beforeIndex = adjustIndex(fieldSection, beforeIndex);
         fieldSection.removeFromParent();
         getChildren().insert(fieldSection, beforeIndex); // This widget's child collection remains 0-indexed...
         DOM.insertChild(fieldSet, fieldSection.getElement(), beforeIndex + 1); // ... but DOM insertion starts with 1.
         adopt(fieldSection);
     }
 
     @Override
     public FormTabWidget getParent() {
         final Widget parent = super.getParent();
         if (parent == null || !(parent instanceof FormTabWidget)) {
             return null;
         }
         return (FormTabWidget) super.getParent();
     }
 
     public void setDescriptionVisible(boolean isAccessible) {
         if (!hasDialogDescriptionHeader()) {
             boolean hasDisplayedFormFieldHelpSection = false;
             for (final FormFieldWrapper fs : sections.values()) {
                 if (fs.isDisplayingHelpSection()) {
                     fs.setHelpEnabled(false);
                     hasDisplayedFormFieldHelpSection = true;
                 }
             }
             if (hasDisplayedFormFieldHelpSection) {
                 return;
             } else if (!isAccessible) {
                 isAccessible = true;
             }
         }
         for (final FormFieldWrapper fs : sections.values()) {
             fs.setHelpEnabled(isAccessible);
         }
     }
 
     private boolean hasDialogDescriptionHeader() {
         Element element = this.getElement();
         while (element != null) {
             if ("dialogDescriptionHeader".equals(element.getAttribute("role"))) {
                 return true;
             }
             element = (Element) element.getParentElement();
         }
         return false;
     }
 
     public List<FormFieldWrapper> getFields() {
         return new ArrayList<FormFieldWrapper>(sections.values());
     }
 
     public void setFieldCaption(Widget widget, String caption) {
         final FormFieldWrapper wrapper = sections.get(widget);
         if (wrapper != null) {
             wrapper.setCaption(caption);
         }
     }
 
     public void setFieldDescription(Widget w, String description) {
         FormFieldWrapper fieldSection = sections.get(w);
         fieldSection.setHelpDescription(description);
     }
 
     public void setCaption(String caption) {
         legend.setInnerText(caption);
     }
 
     public void clearError(Widget widget) {
         sections.get(widget).clearError();
     }
 
     public void setFieldError(Widget widget, String errorMsg) {
         sections.get(widget).showError(errorMsg);
     }
 
     public void focus(Widget widget) {
         scrollTo(sections.get(widget));
     }
 
     private void scrollTo(final FormFieldWrapper field) {
         final int top = JQueryWrapper.select(field).position().top();
         JQueryWrapper.select((Element) getElement().getParentElement().cast())
                 .animate(300, new AnimationSettings() {
                     {
                         setProperty("scrollTop", top - 30);
                         addCallback(new JQueryCallback() {
                             @Override
                             public void execute(JQueryWrapper query) {
                                 new Timer() {
                                     @Override
                                     public void run() {
                                         field.focusField();
                                     }
                                 }.schedule(300);
                             }
                         });
                     }
                 });
     }
 
     public void updateFieldSectionWidths(int offsetWidth) {
         final Iterator<Widget> it = iterator();
         while (it.hasNext()) {
             final Widget w = it.next();
             w.setWidth(offsetWidth + "px");
         }
 
     }
 }