/**
    * 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.ui.vaadin.form.field;
  
  import info.magnolia.icons.MagnoliaIcons;
  import info.magnolia.ui.vaadin.gwt.client.form.field.FieldLayoutState;
  
  import java.util.function.Consumer;
  
  import org.apache.commons.lang3.StringUtils;
  import org.vaadin.jonatan.contexthelp.ContextHelp;
  
  import com.google.common.base.Preconditions;
  import com.vaadin.shared.ui.ContentMode;
  import com.vaadin.ui.AbstractField;
  import com.vaadin.ui.Button;
  import com.vaadin.ui.Component;
  import com.vaadin.ui.HorizontalLayout;
  import com.vaadin.ui.Label;
  import com.vaadin.ui.TabSheet;
  import com.vaadin.ui.UI;
  import com.vaadin.ui.VerticalLayout;
  
  /**
   * A field layout for a field, supporting displaying the error message.
   */
  public class FieldLayout extends VerticalLayout implements Component.Focusable {
  
      private final ContextHelp contextHelp;
      private final boolean isRequired;
  
      private Label statusLabel;
      private final Component field;
      private final String description;
  
      public static FieldLayout of(Component field, String description) {
         return of(field, description, false);
      }
  
      public static FieldLayout of(Component field, String description, boolean isRequired) {
          return new FieldLayout(field, description, isRequired);
      }
  
      private FieldLayout(Component field, String description, boolean isRequired) {
          this.isRequired = isRequired;
          Preconditions.checkNotNull(field);
          this.field = field;
          this.description = description;
          this.contextHelp = UI.getCurrent().getExtensions().stream()
                  .filter(ContextHelp.class::isInstance)
                  .findFirst()
                  .map(ContextHelp.class::cast)
                  .orElse(null);
          initContent();
      }
  
      private void initContent() {
          setMargin(false);
          setVisible(field.isVisible());
  
          statusLabel = new Label(null, ContentMode.HTML);
          statusLabel.setVisible(false);
          statusLabel.addStyleName("validation-display");
  
          Component horizontalLayout = field;
          if (contextHelp != null && StringUtils.isNotEmpty(description)) {
              final Button helpButton = new Button(MagnoliaIcons.HELP_MARK);
              helpButton.addStyleName("help-button v-button-icon icon-button");
 
             contextHelp.extend(UI.getCurrent());
             contextHelp.addHelpForComponent(helpButton, description);
 
             helpButton.addClickListener(event -> {
                 contextHelp.showHelpFor(helpButton);
             });
             HorizontalLayout descriptionLayout = new HorizontalLayout(field, helpButton);
             descriptionLayout.addStyleName("help-button-field-layout");
             descriptionLayout.setSizeFull();
             descriptionLayout.setExpandRatio(field, 1);
             descriptionLayout.setExpandRatio(helpButton, 0);
             descriptionLayout.setSpacing(false);
             horizontalLayout = descriptionLayout;
         }
 
         setCaption(field.getCaption());
         setRequiredIndicatorVisible(isRequired);
 
         addComponents(horizontalLayout, statusLabel);
     }
 
     @Override
     public void setCaption(String caption) {
         super.setCaption(caption);
     }
 
     @Override
     public void setRequiredIndicatorVisible(boolean visible) {
         if (field instanceof AbstractField) {
             ((AbstractField) field).setRequiredIndicatorVisible(false);
         }
         getState().required = visible;
     }
 
     @Override
     protected boolean isRequiredIndicatorVisible() {
         return getState().required;
     }
 
     @Override
     protected FieldLayoutState getState() {
         return (FieldLayoutState) super.getState();
     }
 
     @Override
     public void focus() {
         performTabSelection(field);
         if (field instanceof Focusable) {
             ((Focusable) field).focus();
         }
     }
 
     @Override
     public int getTabIndex() {
         return 0;
     }
 
     @Override
     public void setTabIndex(int tabIndex) {
     }
 
     public Consumer<String> getValidationStatusHandler() {
         return errorMessage -> {
             statusLabel.setValue(errorMessage);
             if (errorMessage.isEmpty()) {
                 field.removeStyleName("error");
                 statusLabel.setVisible(false);
             } else {
                 field.addStyleName("error");
                 // Only show the label when validation has failed
                 statusLabel.setVisible(true);
             }
         };
     }
 
     public Component getField() {
         return field;
     }
 
     /*
      * When focusing field within multiple tabs form we reach TabSheet instance among parents of field
      */
     private void performTabSelection(Component f) {
         Component t = f;
         do {
             f = t;
             t = f.getParent();
         } while (!(t == null || t instanceof TabSheet));
         if (t != null) {
             ((TabSheet) t).setSelectedTab(f);
         }
     }
 }