/*
 * Copyright (c) MuleSoft, Inc.  All rights reserved.  http://www.mulesoft.com
 * The software in this package is published under the terms of the CPAL v1.0
 * license, a copy of which has been included with this distribution in the
 * LICENSE.txt file.
 */
package org.mule.runtime.config.spring.parsers.generic;

import org.mule.runtime.config.spring.parsers.assembly.BeanAssembler;
import org.mule.runtime.config.spring.parsers.assembly.BeanAssemblerFactory;
import org.mule.runtime.config.spring.parsers.assembly.DefaultBeanAssembler;
import org.mule.runtime.config.spring.parsers.assembly.DefaultBeanAssemblerFactory;
import org.mule.runtime.config.spring.parsers.assembly.configuration.PropertyConfiguration;
import org.springframework.beans.MutablePropertyValues;
import org.springframework.beans.PropertyValue;
import org.springframework.beans.factory.config.BeanDefinition;
import org.springframework.beans.factory.support.BeanDefinitionBuilder;
import org.springframework.beans.factory.support.ManagedList;
import org.w3c.dom.Element;

import java.util.List;

/**
 * A child definition parser that wraps the child object
 */
public class WrappingChildDefinitionParser extends ChildDefinitionParser {

  private final Class wrapperClass;
  private final String propertyNameInWrapper;
  private final String unwrappedPropertyName;
  private final WrappingController wrappingController;

  public WrappingChildDefinitionParser(String setterMethod, Class clazz, Class constraint, boolean allowClassAttribute,
                                       Class wrapperClass, String propertyNameInWrapper, String unwrappedPropertyName,
                                       WrappingController wrappingController) {
    super(setterMethod, clazz, constraint, allowClassAttribute);
    this.wrapperClass = wrapperClass;
    this.propertyNameInWrapper = propertyNameInWrapper;
    this.unwrappedPropertyName = unwrappedPropertyName;
    this.wrappingController = wrappingController;
  }

  @Override
  public String getPropertyName(Element e) {
    if (!wrappingController.shouldWrap(e)) {
      return unwrappedPropertyName;
    } else {
      return super.getPropertyName(e);
    }
  }

  @Override
  protected void preProcess(Element element) {
    super.preProcess(element);
    if (wrappingController.shouldWrap(element)) {
      setBeanAssemblerFactory(new MessageProcessorWrappingBeanAssemblerFactory(wrapperClass, propertyNameInWrapper));
    } else {
      setBeanAssemblerFactory(new DefaultBeanAssemblerFactory());
    }
  }

  /**
   * Determines whether to wrap the child based on the where it appears in the DOM.
   */
  public interface WrappingController {

    boolean shouldWrap(Element elm);
  }

  private static class MessageProcessorWrappingBeanAssemblerFactory implements BeanAssemblerFactory {

    private final Class wrapperClass;
    private final String propertyNameInWrapper;

    public MessageProcessorWrappingBeanAssemblerFactory(Class wrapperClass, String propertyNameInWrapper) {
      this.wrapperClass = wrapperClass;
      this.propertyNameInWrapper = propertyNameInWrapper;
    }

    public BeanAssembler newBeanAssembler(PropertyConfiguration beanConfig, BeanDefinitionBuilder bean,
                                          PropertyConfiguration targetConfig, BeanDefinition target) {
      return new MessageProcessorWrappingBeanAssembler(beanConfig, bean, targetConfig, target, wrapperClass,
                                                       propertyNameInWrapper);
    }
  }

  private static class MessageProcessorWrappingBeanAssembler extends DefaultBeanAssembler {

    private final Class wrapperClass;
    private final String propertyNameInWrapper;

    public MessageProcessorWrappingBeanAssembler(PropertyConfiguration beanConfig, BeanDefinitionBuilder bean,
                                                 PropertyConfiguration targetConfig, BeanDefinition target, Class wrapperClass,
                                                 String propertyNameInWrapper) {
      super(beanConfig, bean, targetConfig, target);
      this.wrapperClass = wrapperClass;
      this.propertyNameInWrapper = propertyNameInWrapper;
    }

    public void insertBeanInTarget(String oldName) {
      if (target == null) {
        // TODO MULE-9638 - This is possible when the parent node is parsed by the new mechanism
        return;
      }
      String newName = bestGuessName(targetConfig, oldName, target.getBeanClassName());
      MutablePropertyValues targetProperties = target.getPropertyValues();
      PropertyValue pv = targetProperties.getPropertyValue(newName);
      Object oldValue = null == pv ? null : pv.getValue();

      BeanDefinitionBuilder wrapper = BeanDefinitionBuilder.genericBeanDefinition(wrapperClass);
      wrapper.addPropertyValue(propertyNameInWrapper, bean.getBeanDefinition());

      if (oldValue == null) {
        oldValue = new ManagedList();
        pv = new PropertyValue(newName, oldValue);
        targetProperties.addPropertyValue(pv);
      }
      if (targetConfig.isCollection(oldName)) {
        List list = retrieveList(oldValue);
        list.add(wrapper.getBeanDefinition());
      } else {
        targetProperties.addPropertyValue(newName, wrapper.getBeanDefinition());
      }
    }
  }
}