/**
    * This file Copyright (c) 2013-2018 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.form.field;
  
  import info.magnolia.cms.i18n.I18nContentSupport;
  import info.magnolia.objectfactory.ComponentProvider;
  import info.magnolia.ui.api.i18n.I18NAuthoringSupport;
  import info.magnolia.ui.form.field.definition.ConfiguredFieldDefinition;
  import info.magnolia.ui.form.field.definition.FieldDefinition;
  import info.magnolia.ui.form.field.factory.FieldFactory;
  import info.magnolia.ui.form.field.factory.FieldFactoryFactory;
  import info.magnolia.ui.vaadin.integration.ItemAdapter;
  import info.magnolia.ui.vaadin.integration.NullItem;
  import info.magnolia.ui.vaadin.server.ErrorMessageUtil;
  
  import java.util.ArrayList;
  import java.util.Iterator;
  import java.util.List;
  import java.util.Locale;
  
  import org.apache.commons.lang3.StringUtils;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import com.vaadin.server.AbstractErrorMessage.ContentMode;
  import com.vaadin.server.CompositeErrorMessage;
  import com.vaadin.server.ErrorMessage;
  import com.vaadin.server.UserError;
  import com.vaadin.ui.AbstractOrderedLayout;
  import com.vaadin.ui.Component;
  import com.vaadin.ui.HasComponents;
  import com.vaadin.v7.data.Item;
  import com.vaadin.v7.data.Property;
  import com.vaadin.v7.data.util.PropertysetItem;
  import com.vaadin.v7.ui.AbstractField;
  import com.vaadin.v7.ui.CustomField;
  import com.vaadin.v7.ui.Field;
  
  /**
   * Abstract implementation of {@link CustomField} used for multi fields components.<br>
   * It expose generic methods allowing to: <br>
   * - Build a {@link Field} based on a {@link ConfiguredFieldDefinition}. <br>
   * - Retrieve the list of Fields contained into the main component <br>
   * - Override Validate and get Error Message in order to include these call to the embedded Fields.<br>
   *
   * @param <T> Property Type linked to this Field.
   * @param <D> FieldDefinition Implementation used by the implemented Field.
   */
  public abstract class AbstractCustomMultiField<D extends FieldDefinition, T> extends CustomField<T> {
  
      private static final Logger log = LoggerFactory.getLogger(AbstractCustomMultiField.class);
  
      protected final FieldFactoryFactory fieldFactoryFactory;
  
      /** @deprecated since 5.3.5 (actually unused way before that). Besides, fields should use i18nAuthoringSupport for internationalization. */
      @Deprecated
      protected final I18nContentSupport i18nContentSupport = null;
  
      protected final ComponentProvider componentProvider;
      protected final D definition;
      protected final Item relatedFieldItem;
      protected AbstractOrderedLayout root;
  
      protected AbstractCustomMultiField(D definition, FieldFactoryFactory fieldFactoryFactory, ComponentProvider componentProvider, Item relatedFieldItem, I18NAuthoringSupport i18nAuthoringSupport) {
          this.definition = definition;
          this.fieldFactoryFactory = fieldFactoryFactory;
          this.componentProvider = componentProvider;
          this.relatedFieldItem = relatedFieldItem;
     }
 
     /**
      * @deprecated since 5.3.5 removing i18nContentSupport dependency (actually unused way before that). Besides, fields should use i18nAuthoringSupport for internationalization.
      */
     @Deprecated
     protected AbstractCustomMultiField(D definition, FieldFactoryFactory fieldFactoryFactory, I18nContentSupport i18nContentSupport, ComponentProvider componentProvider, Item relatedFieldItem) {
         this(definition, fieldFactoryFactory, componentProvider, relatedFieldItem, componentProvider.getComponent(I18NAuthoringSupport.class));
     }
 
     /**
      * Initialize the fields based on the newValues.<br>
      * Implemented logic should: <br>
      * - remove all component from the root component. <br>
      * - for every fieldValues value, add the appropriate field.<br>
      * - add all others needed component (like add button...)
      */
     protected abstract void initFields(T fieldValues);
 
     /**
      * Handle {@link info.magnolia.ui.api.i18n.I18NAuthoringSupport#i18nize(HasComponents, Locale)} events in order to refresh the field <br>
      * and display the new property.
      */
     @Override
     public void setLocale(Locale locale) {
         if (root != null) {
             initFields();
         }
         super.setLocale(locale);
     }
 
     @SuppressWarnings("unchecked")
     protected void initFields() {
         T fieldValues = (T) getPropertyDataSource().getValue();
         initFields(fieldValues);
         // Update DataSource in order to handle the fields default values
         if (relatedFieldItem instanceof ItemAdapter/../../info/magnolia/ui/vaadin/integration/ItemAdapter.html#ItemAdapter">ItemAdapter && ((ItemAdapter) relatedFieldItem).isNew() && !definition.isReadOnly()) {
             getPropertyDataSource().setValue(getValue());
         }
     }
 
     /**
      * Helper method to find propertyId for a given property within item datasource.
      */
     protected int findPropertyId(Item item, Property<?> property) {
         Iterator<?> it = item.getItemPropertyIds().iterator();
         while (it.hasNext()) {
             Object pos = it.next();
             if (pos.getClass().isAssignableFrom(Integer.class) && property == item.getItemProperty(pos)) {
                 return (Integer) pos;
             } else {
                 log.debug("Property id {} is not an integer and as such property can't be located", pos);
             }
         }
         return -1;
     }
 
     /**
      * Create a new {@link Field} based on a {@link FieldDefinition}.
      */
     protected Field<?> createLocalField(FieldDefinition fieldDefinition, Property<?> property, boolean setCaptionToNull) {
 
         // If the property holds an item, use this item directly for the field creation (doesn't apply to ProperysetItems)
         FieldFactory fieldfactory = fieldFactoryFactory.createFieldFactory(fieldDefinition, holdsItem(property) ? property.getValue() : new NullItem());
         fieldfactory.setComponentProvider(componentProvider);
         // FIXME change i18n setting : MGNLUI-1548
         if (fieldDefinition instanceof ConfiguredFieldDefinition) {
             ((ConfiguredFieldDefinition) fieldDefinition).setI18nBasename(definition.getI18nBasename());
         }
         Field<?> field = fieldfactory.createField();
 
         // If the value property is not an Item but a property, set this property as datasource to the field
         // and add a value change listener in order to propagate changes
         if (!holdsItem(property)) {
             if (property != null && property.getValue() != null) {
                 field.setPropertyDataSource(property);
             }
             field.addValueChangeListener(selectionListener);
         }
 
         // Set Caption if desired
         if (setCaptionToNull) {
             field.setCaption(null);
         } else if (StringUtils.isBlank(field.getCaption()) && StringUtils.isNotBlank(fieldDefinition.getLabel())) {
             field.setCaption(fieldDefinition.getLabel());
         }
 
         field.setWidth(100, Unit.PERCENTAGE);
 
         // propagate locale to complex fields further down, in case they have i18n-aware fields
         if (field instanceof AbstractCustomMultiField) {
             ((AbstractCustomMultiField) field).setLocale(getLocale());
         }
 
         // Set read only based on the single field definition
         field.setReadOnly(fieldDefinition.isReadOnly());
 
         return field;
     }
 
     boolean holdsItem(Property<?> property) {
         return property != null && property.getValue() instanceof Item && !(property.getValue() instanceof PropertysetItem);
     }
 
     /**
      * Listener used to update the Data source property.
      */
     protected Property.ValueChangeListener selectionListener = new ValueChangeListener() {
         @SuppressWarnings("unchecked")
         @Override
         public void valueChange(com.vaadin.v7.data.Property.ValueChangeEvent event) {
             fireValueChange(false);
             // In case PropertysetItem is used as property set of field's property, in case an individual field is updated, the PropertysetItem is coherent (has also the changes)
             // but the setValue on the property is never called.
             getPropertyDataSource().setValue(getValue());
         }
     };
 
     /**
      * Utility method that return a list of Fields embedded into a root custom field.
      *
      * @param root
      * @param onlyValid if set to true, return only the isValid() fields.
      */
     @SuppressWarnings("unchecked")
     protected List<AbstractField<T>> getFields(HasComponents root, boolean onlyValid) {
         Iterator<Component> it = root.iterator();
         List<AbstractField<T>> fields = new ArrayList<>();
         while (it.hasNext()) {
             Component c = it.next();
             if (c instanceof AbstractField) {
                 if (!onlyValid || (((AbstractField<T>) c).isValid())) {
                     fields.add((AbstractField<T>) c);
                 }
             } else if (c instanceof HasComponents) {
                 fields.addAll(getFields((HasComponents) c, onlyValid));
             }
         }
         return fields;
     }
 
     /**
      * Validate all fields from the root container. Fields which are not visible are skipped. Stops at the first error encountered.
      */
     @Override
     public boolean isValid() {
         // first validate self
         if (!super.isValid()) {
             // TODO: This is temporary and when MGNLUI-3668 is fixed, should be deleted.
             markAsDirty();
             return false;
         }
 
         List<AbstractField<T>> fields = getFields(this, false);
         for (AbstractField<T> field : fields) {
             if (!field.isVisible()) {
                 continue;
             }
             if (!field.isValid()) {
                 // TODO: This is temporary and when MGNLUI-3668 is fixed, should be deleted.
                 markAsDirty();
                 return false;
             }
         }
         return true;
     }
 
     /**
      * Get the error message, if any. Aggregates all errors for all fields in this custom multi field.
      */
     @Override
     public ErrorMessage getErrorMessage() {
         List<ErrorMessage> errors = new ArrayList<>();
         ErrorMessage errorMessage = super.getErrorMessage();
         if (errorMessage != null) {
             errors.add(errorMessage);
         }
         List<AbstractField<T>> fields = getFields(this, false);
 
         for (AbstractField<T> field : fields) {
             // skip non visible fields or validation will pass (see this class isValid() method) but an annoying error message will display just for a moment (e.g. before a form is closed).
             if (!field.isVisible()) {
                 continue;
             }
             errorMessage = field.getErrorMessage();
             if (errorMessage != null) {
                 String errorAsString = getFormattedHtmlAggregatedErrorMessage(errorMessage, field.getCaption());
                 errors.add(new UserError(errorAsString, ContentMode.HTML, errorMessage.getErrorLevel()));
             }
         }
         return errors.isEmpty() ? null : new CompositeErrorMessage(errors);
     }
 
     /**
      * For a custom multi field <em>empty</em> means it contains no sub-fields <em>OR</em> at least one of its sub-fields <code>isEmpty()</code> method returns <code>true</code>.
      */
     @Override
     public boolean isEmpty() {
         List<AbstractField<T>> fields = getFields(this, false);
         if (fields.isEmpty()) {
             return true;
         }
         for (AbstractField<T> field : fields) {
             if (!field.isVisible()) {
                 continue;
             }
             if (field.isEmpty()) {
                 return true;
             }
         }
         return false;
     }
 
     private String getFormattedHtmlAggregatedErrorMessage(final ErrorMessage message, final String caption) {
         return (StringUtils.isNotBlank(caption) ? caption + ": " : "") + StringUtils.join(ErrorMessageUtil.getCausesMessages(message), ", ");
     }
 }