/**
    * This file Copyright (c) 2012-2013 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.form.field.factory;
  
  import info.magnolia.cms.i18n.I18nContentSupport;
  import info.magnolia.objectfactory.ComponentProvider;
  import info.magnolia.ui.api.view.View;
  import info.magnolia.ui.form.AbstractFormItem;
  import info.magnolia.ui.form.field.definition.FieldDefinition;
  import info.magnolia.ui.form.field.definition.TextFieldDefinition;
  import info.magnolia.ui.form.field.transformer.TransformedProperty;
  import info.magnolia.ui.form.field.transformer.Transformer;
  import info.magnolia.ui.form.field.transformer.UndefinedPropertyType;
  import info.magnolia.ui.form.field.transformer.basic.BasicTransformer;
  import info.magnolia.ui.form.validator.definition.FieldValidatorDefinition;
  import info.magnolia.ui.form.validator.factory.FieldValidatorFactory;
  import info.magnolia.ui.form.validator.registry.FieldValidatorFactoryFactory;
  import info.magnolia.ui.vaadin.integration.ItemAdapter;
  import info.magnolia.ui.vaadin.integration.jcr.DefaultPropertyUtil;
  
  import java.util.Locale;
  
  import org.apache.commons.lang.StringUtils;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import com.vaadin.data.Item;
  import com.vaadin.data.Property;
  import com.vaadin.data.util.converter.AbstractStringToNumberConverter;
  import com.vaadin.server.Sizeable.Unit;
  import com.vaadin.ui.AbstractTextField;
  import com.vaadin.ui.Component;
  import com.vaadin.ui.CssLayout;
  import com.vaadin.ui.Field;
  import com.vaadin.ui.Label;
  
  /**
   * Abstract FieldFactory implementations. This class handle all common attributes defined in {@link FieldDefinition} and binds Vaadin {@link Field} instances created
   * by subclasses to the {@link Property} they will be reading and writing to.
   * 
   * @param <D> definition type
   * @param <T> field value type
   */
  public abstract class AbstractFieldFactory<D extends FieldDefinition, T> extends AbstractFormItem implements FieldFactory {
      private static final Logger log = LoggerFactory.getLogger(AbstractFieldFactory.class);
      protected Item item;
      protected Field<T> field;
      protected D definition;
      private FieldValidatorFactoryFactory fieldValidatorFactoryFactory;
      private I18nContentSupport i18nContentSupport;
      private ComponentProvider componentProvider;
  
      public AbstractFieldFactory(D definition, Item relatedFieldItem) {
          this.definition = definition;
          this.item = relatedFieldItem;
      }
  
      @Override
      public void setFieldValidatorFactoryFactory(FieldValidatorFactoryFactory fieldValidatorFactoryFactory) {
          this.fieldValidatorFactoryFactory = fieldValidatorFactoryFactory;
      }
  
      @Override
      public void setI18nContentSupport(I18nContentSupport i18nContentSupport) {
          this.i18nContentSupport = i18nContentSupport;
      }
  
      @Override
     public Field<T> createField() {
         if (field == null) {
             // Create the Vaadin field
             this.field = createFieldComponent();
 
             Property<?> property = initializeProperty();
 
             // MGNLUI-1855 we need to assign converter for properties with type Long because otherwise Vaadin assigns incompatible StringToNumberConverter.
             if (Long.class.equals(property.getType()) && field instanceof AbstractTextField) {
                 ((AbstractTextField) field).setConverter(new StringToLongConverter());
             }
             // Set the created property with the default value as field Property datasource.
             setPropertyDataSourceAndDefaultValue(property);
 
             if (StringUtils.isNotBlank(definition.getStyleName())) {
                 this.field.addStyleName(definition.getStyleName());
             }
 
             field.setWidth(100, Unit.PERCENTAGE);
 
             // Set label and required marker
             this.field.setCaption(getFieldDefinition().getLabel() + (getFieldDefinition().isRequired() ? "<span class=\"requiredfield\">*</span>" : ""));
 
             setConstraints();
 
         }
         return this.field;
     }
 
     /**
      * Set the DataSource of the current field.<br>
      * Set the default value if : <br>
      * - the item is an instance of {@link ItemAdapter} and this is a new Item (Not yet stored in the related datasource)
      * - the item is not an instance of {@link ItemAdapter}.<br>
      * In this case, the Item is a custom implementation of {@link Item} and we have no possibility to define if it is or not a new Item.
      */
     public void setPropertyDataSourceAndDefaultValue(Property<?> property) {
         this.field.setPropertyDataSource(property);
 
         if ((item instanceof ItemAdapter && ((ItemAdapter) item).isNew()) || !(item instanceof ItemAdapter)) {
             setPropertyDataSourceDefaultValue(property);
         }
     }
 
     /**
      * Set the Field default value is required.
      */
     protected void setPropertyDataSourceDefaultValue(Property property) {
         Object defaultValue = createDefaultValue(property);
         if (defaultValue != null && !definition.isReadOnly()) {
             if (defaultValue.getClass().isAssignableFrom(property.getType())) {
                 property.setValue(defaultValue);
             } else {
                 log.warn("Default value {} is not assignable to the field of type {}.", defaultValue, field.getPropertyDataSource().getType().getName());
             }
         }
     }
 
     /**
      * Create a typed default value.
      */
     protected Object createDefaultValue(Property<?> property) {
         String defaultValue = definition.getDefaultValue();
         if (StringUtils.isNotBlank(defaultValue)) {
             return DefaultPropertyUtil.createTypedValue(property.getType(), defaultValue);
         }
         return null;
     }
 
     @Override
     public D getFieldDefinition() {
         return this.definition;
     }
 
     /**
      * Implemented by subclasses to create and initialize the Vaadin Field instance to use.
      */
     protected abstract Field<T> createFieldComponent();
 
     @Override
     public View getView() {
         Property<?> property = initializeProperty();
 
         final CssLayout fieldView = new CssLayout();
         fieldView.setStyleName("field-view");
 
         Label label = new Label();
         label.setSizeUndefined();
         label.setCaption(getFieldDefinition().getLabel());
 
         if (getFieldDefinition().getClass().isAssignableFrom(TextFieldDefinition.class)) {
             final TextFieldDefinition textFieldDefinition = (TextFieldDefinition) getFieldDefinition();
             if (textFieldDefinition.getRows() > 0) {
                 label.addStyleName("textarea");
             }
         }
         label.setPropertyDataSource(property);
 
         fieldView.addComponent(label);
 
         return new View() {
             @Override
             public Component asVaadinComponent() {
                 return fieldView;
             }
         };
     }
 
     /**
      * Initialize the property used as field's Datasource.<br>
      * If no {@link Transformer} is configure to the field definition, use the default {@link BasicTransformer} <br>
      */
     @SuppressWarnings("unchecked")
     private Property<?> initializeProperty() {
         Class<? extends Transformer<?>> transformerClass = definition.getTransformerClass();
 
         if (transformerClass == null) {
             // TODO explain why down cast
             transformerClass = (Class<? extends Transformer<?>>) (Object) BasicTransformer.class;
         }
         Transformer<?> transformer = initializeTransformer(transformerClass);
 
         return new TransformedProperty(transformer);
     }
 
     /**
      * Exposed method used by field's factory to initialize the property {@link Transformer}.<br>
      * This allows to add additional constructor parameter if needed.<br>
      */
     protected Transformer<?> initializeTransformer(Class<? extends Transformer<?>> transformerClass) {
         return this.componentProvider.newInstance(transformerClass, item, definition, getFieldType());
     }
 
     /**
      * Define the field property value type Class.<br>
      * Return the value defined by the configuration ('type' property).<br>
      * If this value is not defined, return the value of the overriding method {@link AbstractFieldFactory#getDefaultFieldType()}.<br>
      * If this method is not override, return {@link UndefinedPropertyType}.<br>
      * In this case, the {@link Transformer} will have the responsibility to define the property type.
      */
     protected Class<?> getFieldType() {
         Class<?> type = getDefinitionType();
         if (type == null) {
             type = getDefaultFieldType();
         }
         return type;
     }
 
     /**
      * @return Class Type defined into the field definition or null if not defined.
      */
     protected Class<?> getDefinitionType() {
         if (StringUtils.isNotBlank(definition.getType())) {
             return DefaultPropertyUtil.getFieldTypeClass(definition.getType());
         }
         return null;
     }
 
     /**
      * Exposed method used by field's factory in order to define a default Field Type (decoupled from the definition).
      */
     protected Class<?> getDefaultFieldType() {
         return UndefinedPropertyType.class;
     }
 
     @Override
     protected String getI18nBasename() {
         return definition.getI18nBasename();
     }
 
     /**
      * Set all constraints linked to the field:
      * Build Validation rules.
      * Set Required field.
      * Set Read Only.
      */
     private void setConstraints() {
         // Set Validation
         for (FieldValidatorDefinition validatorDefinition : definition.getValidators()) {
             FieldValidatorFactory validatorFactory = this.fieldValidatorFactoryFactory.createFieldValidatorFactory(validatorDefinition, item);
             if (validatorFactory != null) {
                 this.field.addValidator(validatorFactory.createValidator());
             } else {
                 log.warn("Not able to create Validation for the following definition {}", definition.toString());
             }
         }
         // Set Required
         if (definition.isRequired()) {
             field.setRequired(true);
             field.setRequiredError(definition.getRequiredErrorMessage());
         }
 
         // Set ReadOnly (field property has to be updated)
         if (field.getPropertyDataSource() != null) {
             field.getPropertyDataSource().setReadOnly(definition.isReadOnly());
         }
     }
 
     @Override
     public void setComponentProvider(ComponentProvider componentProvider) {
         this.componentProvider = componentProvider;
     }
 
     /**
      * The StringToLongConverter.<br>
      * MGNLUI-1855 This should be handled by vaadin, but StringToNumberConverter throws conversion exception when used
      * with a Long property in Vaadin 7.1. This should be fixed, unfortunately not before 7.2, so we need that converter
      * for the time being.<br>
      * As a result, this class will have a short life span, this is why it is kept private and deprecated.
      */
     @Deprecated
     private static class StringToLongConverter extends AbstractStringToNumberConverter<Long> {
 
         @Override
         public Long convertToModel(String value, Class<? extends Long> targetType, Locale locale) throws ConversionException {
             Number n = convertToNumber(value, targetType, locale);
             return n == null ? null : n.longValue();
         }
 
         @Override
         public Class<Long> getModelType() {
             return Long.class;
         }
     }
 
 }