/*
 * 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.core.transformer.simple;

import org.mule.runtime.api.metadata.DataType;
import org.mule.runtime.api.lifecycle.InitialisationException;
import org.mule.runtime.core.api.transformer.DiscoverableTransformer;
import org.mule.runtime.core.api.transformer.TransformerException;
import org.mule.runtime.core.config.i18n.CoreMessages;
import org.mule.runtime.core.transformer.AbstractTransformer;
import org.mule.runtime.core.util.BeanUtils;
import org.mule.runtime.core.util.ClassUtils;

import java.nio.charset.Charset;
import java.util.Map;

/**
 * Creates and object of type {@code getReturnDataType().getType()} and populates values of a {@link java.util.Map} as bean
 * properties on the object. The bean class name can also be passed in as a property on the Map (which gets removed once read).
 * The {@link MapToBean#CLASS_PROPERTY} should be set as a fully qualified class name string.
 */
public class MapToBean extends AbstractTransformer implements DiscoverableTransformer {

  /**
   * {@value}
   */
  public static final String CLASS_PROPERTY = "className";

  private int priorityWeighting = DiscoverableTransformer.DEFAULT_PRIORITY_WEIGHTING;

  public MapToBean() {
    registerSourceType(DataType.fromType(Map.class));
    setReturnDataType(DataType.OBJECT);
  }

  @Override
  public void initialise() throws InitialisationException {
    super.initialise();
    if (Object.class.equals(getReturnDataType().getType())) {
      throw new InitialisationException(CoreMessages.propertiesNotSet("returnClass"), this);
    }
  }

  @Override
  protected Object doTransform(Object src, Charset encoding) throws TransformerException {
    try {
      Map props = (Map) src;
      String c = (String) props.remove(CLASS_PROPERTY);
      Class clazz = getReturnDataType().getType();
      if (c == null && Object.class.equals(clazz)) {
        throw new TransformerException(CoreMessages.transformerMapBeanClassNotSet());
      } else if (c != null) {
        clazz = ClassUtils.loadClass(c, getClass());
      }

      Object result = ClassUtils.instanciateClass(clazz, ClassUtils.NO_ARGS);
      BeanUtils.populate(result, props);

      return result;
    } catch (Exception e) {
      throw new TransformerException(this, e);
    }
  }

  @Override
  public int getPriorityWeighting() {
    return priorityWeighting;
  }

  @Override
  public void setPriorityWeighting(int weighting) {
    priorityWeighting = weighting;
  }
}