/**
    * This file Copyright (c) 2020 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.framework.layout.field;
  
  import info.magnolia.icons.MagnoliaIcons;
  import info.magnolia.objectfactory.annotation.Multibinding;
  import info.magnolia.ui.field.EditorPropertyDefinition;
  import info.magnolia.ui.field.ValueBoundProperty;
  
  import java.util.Optional;
  
  import javax.inject.Inject;
  
  import org.apache.commons.lang3.StringUtils;
  import org.vaadin.jonatan.contexthelp.ContextHelp;
  
  import com.vaadin.ui.AbstractField;
  import com.vaadin.ui.Button;
  import com.vaadin.ui.Component;
  import com.vaadin.ui.CustomField;
  import com.vaadin.ui.Label;
  import com.vaadin.ui.TabSheet;
  import com.vaadin.ui.UI;
  
  /**
   * Component to be displayed together with each form field.
   * Register in a module descriptor and the component will be included automatically.
   * You can scope your custom component to an app in the module descriptor declaration (e.g. {@code <id>app-pages-app</id>}).
   *
   * @see info.magnolia.ui.framework.layout.field.FieldLayoutComponent.Description Description as an example.
   * @see info.magnolia.ui.framework.layout.field.FieldLayoutComponent.ValidationLabel ValidationLabel as an example.
   */
  @Multibinding
  public interface FieldLayoutComponent extends Component {
  
      /**
       * Initialisation of component might react according to the field definition or with the inner field itself.
       */
      void init(EditorPropertyDefinition definition, Component innerField);
  
      default Position getPosition() {
          return Position.horizontal;
      }
  
      enum Position {
          /**
           * Component to be displayed below each form field.
           */
          vertical,
          /**
           * Component to be displayed next to each form field.
           */
          horizontal
      }
  
      class ValidationLabel extends Label implements FieldLayoutComponent {
  
          private Component field;
  
          @Override
          public void init(EditorPropertyDefinition definition, Component innerField) {
              this.field = innerField;
              addStyleName("validation-display");
          }
  
          @Override
          public Position getPosition() {
              return Position.vertical;
         }
 
         @Override
         public void setValue(String value) {
             super.setValue(value);
             if (value.isEmpty()) {
                 Optional.ofNullable(field).ifPresent(component -> component.removeStyleName("error"));
                 setVisible(false);
             } else {
                 Optional.ofNullable(field).ifPresent(component -> component.addStyleName("error"));
                 // Only show the label when validation has failed
                 setVisible(true);
             }
         }
     }
 
     class Description extends Button implements FieldLayoutComponent {
 
         private final UI ui;
 
         @Inject
         Description(UI ui) {
             this.ui = ui;
         }
 
         @Override
         public void init(EditorPropertyDefinition definition, Component innerField) {
             if (StringUtils.isNotEmpty(definition.getDescription())) {
                 setIcon(MagnoliaIcons.HELP_MARK);
                 addStyleName("help-button v-button-icon icon-button");
                 ContextHelp contextHelp = ui.getExtensions().stream()
                         .filter(ContextHelp.class::isInstance)
                         .findFirst()
                         .map(ContextHelp.class::cast)
                         .orElseGet(() -> {
                             final ContextHelp help = new ContextHelp();
                             help.extend(ui);
                             return help;
                         });
                 addClickListener(event -> contextHelp.showHelpFor(this));
                 contextHelp.addHelpForComponent(this, definition.getDescription());
             } else {
                 setVisible(false);
             }
         }
     }
 
     class Root<T> extends CustomField<T> {
 
         private final Component root;
         private final Component field;
 
         @Inject
         Root(Component mainField, Component root, EditorPropertyDefinition definition) {
             this.field = mainField;
             this.root = root;
             this.addStyleName("form-field-layout");
             mainField.addStyleName("hide-caption");
 
             setCaption(field.getCaption());
             setVisible(field.isVisible());
             relayRequirementIndicator(mainField, definition);
             getContent();
         }
 
         /**
          * Let the field wrapper take over the requirement indicator rendering.
          */
         private void relayRequirementIndicator(Component mainField, EditorPropertyDefinition definition) {
             setRequiredIndicatorVisible(definition instanceof ValueBoundProperty && ((ValueBoundProperty<?>) definition).isRequired());
             if (mainField instanceof AbstractField) {
                 ((AbstractField) mainField).setRequiredIndicatorVisible(false);
             }
         }
 
         @Override
         protected Component initContent() {
             return root;
         }
 
         @Override
         protected void doSetValue(T value) {
         }
 
         @Override
         public T getValue() {
             return null;
         }
 
         @Override
         public void focus() {
             performTabSelection(field);
             if (field instanceof Focusable) {
                 ((Focusable) field).focus();
             }
         }
 
         /*
          * 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);
             }
         }
     }
 }