/*
 * 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.specific;

import org.mule.runtime.config.spring.parsers.delegate.ParentContextDefinitionParser;
import org.mule.runtime.config.spring.parsers.generic.ChildDefinitionParser;
import org.mule.runtime.config.spring.parsers.generic.MuleOrphanDefinitionParser;
import org.mule.runtime.config.spring.parsers.processors.CheckExclusiveAttributesAndChildren;
import org.mule.runtime.config.spring.parsers.processors.CheckRequiredAttributesWhenNoChildren;
import org.mule.runtime.core.expression.ExpressionConfig;
import org.mule.runtime.core.expression.transformers.ExpressionArgument;

import org.springframework.beans.factory.support.BeanDefinitionBuilder;
import org.springframework.beans.factory.support.GenericBeanDefinition;
import org.springframework.beans.factory.support.ManagedList;
import org.springframework.beans.factory.xml.ParserContext;
import org.w3c.dom.Element;

/**
 * This allows a message processor to be defined globally, or embedded within an endpoint. (as either a normal or response
 * processor).
 */
public class ExpressionTransformerDefinitionParser extends ParentContextDefinitionParser {

  public ExpressionTransformerDefinitionParser(Class messageProcessor) {
    super(MuleOrphanDefinitionParser.ROOT_ELEMENT, new ExpressionTransformerOrphanDefinitionParser(messageProcessor, false));
    otherwise(new ExpressionTransformerChildDefinitionParser("messageProcessor", messageProcessor));

    registerPreProcessor(new CheckRequiredAttributesWhenNoChildren(new String[][] {{"expression"}}, "return-argument",
                                                                   "http://www.mulesoft.org/schema/mule/core"))
                                                                       .registerPreProcessor(new CheckExclusiveAttributesAndChildren(new String[] {
                                                                           "expression"}, new String[] {"return-argument"}))
                                                                       .addIgnored("expression");
  }

  protected static void addExpressionArgumentFromAttributes(Element element, BeanDefinitionBuilder builder) {
    if (element.getAttributeNode("expression") != null) {
      GenericBeanDefinition objectFactoryBeanDefinition = new GenericBeanDefinition();
      objectFactoryBeanDefinition.setBeanClass(ExpressionArgument.class);
      objectFactoryBeanDefinition.getPropertyValues().addPropertyValue("name", "single");
      objectFactoryBeanDefinition.getPropertyValues().addPropertyValue("optional", false);
      GenericBeanDefinition objectFactoryBeanDefinition2 = new GenericBeanDefinition();
      objectFactoryBeanDefinition2.setBeanClass(ExpressionConfig.class);
      objectFactoryBeanDefinition2.getPropertyValues().addPropertyValue("expression", element.getAttribute("expression"));
      objectFactoryBeanDefinition.getPropertyValues().addPropertyValue("expressionConfig", objectFactoryBeanDefinition2);
      ManagedList list = new ManagedList<ExpressionArgument>(1);
      list.add(objectFactoryBeanDefinition2);
      builder.getBeanDefinition().getPropertyValues().addPropertyValue("arguments", objectFactoryBeanDefinition);
    }
  }

  static class ExpressionTransformerChildDefinitionParser extends ChildDefinitionParser {

    public ExpressionTransformerChildDefinitionParser(String string, Class messageProcessor) {
      super(string, messageProcessor);
    }

    @Override
    protected void parseChild(Element element, ParserContext parserContext, BeanDefinitionBuilder builder) {
      addExpressionArgumentFromAttributes(element, builder);
      super.parseChild(element, parserContext, builder);
    }
  }

  static class ExpressionTransformerOrphanDefinitionParser extends MuleOrphanDefinitionParser {

    public ExpressionTransformerOrphanDefinitionParser(Class<?> beanClass, boolean singleton) {
      super(beanClass, singleton);
    }

    @Override
    protected void doParse(Element element, ParserContext context, BeanDefinitionBuilder builder) {
      addExpressionArgumentFromAttributes(element, builder);
      super.doParse(element, context, builder);
    }
  }
}