package com.sjtu.util;

import com.sjtu.model.BaseObject;
import com.sjtu.model.LabelValue;
import org.apache.commons.beanutils.BeanUtils;
import org.apache.commons.beanutils.PropertyUtils;
import org.apache.commons.lang.StringUtils;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.aop.support.AopUtils;

import java.beans.PropertyDescriptor;
import java.util.*;

/**
 * Utility class to convert one object to another.
 * 
 * <p>
 * <a href="ConvertUtil.java.html"><i>View Source</i></a>
 * </p>
 * 
 * @author <a href="mailto:matt@raibledesigns.com">Matt Raible</a>
 */
public final class ConvertUtil {
	// ~ Static fields/initializers
	// =============================================

	private static Log log = LogFactory.getLog(ConvertUtil.class);

	// ~ Methods
	// ================================================================

	/**
	 * Method to convert a ResourceBundle to a Map object.
	 * 
	 * @param rb
	 *            a given resource bundle
	 * @return Map a populated map
	 */
	public static Map convertBundleToMap(ResourceBundle rb) {
		Map map = new HashMap();

		for (Enumeration keys = rb.getKeys(); keys.hasMoreElements();) {
			String key = (String) keys.nextElement();
			map.put(key, rb.getString(key));
		}

		return map;
	}

	public static Map convertListToMap(List list) {
		Map map = new LinkedHashMap();

		for (Iterator it = list.iterator(); it.hasNext();) {
			LabelValue option = (LabelValue) it.next();
			map.put(option.getLabel(), option.getValue());
		}

		return map;
	}

	/**
	 * Method to convert a ResourceBundle to a Properties object.
	 * 
	 * @param rb
	 *            a given resource bundle
	 * @return Properties a populated properties object
	 */
	public static Properties convertBundleToProperties(ResourceBundle rb) {
		Properties props = new Properties();

		for (Enumeration keys = rb.getKeys(); keys.hasMoreElements();) {
			String key = (String) keys.nextElement();
			props.put(key, rb.getString(key));
		}

		return props;
	}

	/**
	 * Convenience method used by tests to populate an object from a
	 * ResourceBundle
	 * 
	 * @param obj
	 *            an initialized object
	 * @param rb
	 *            a resource bundle
	 * @return a populated object
	 */
	public static Object populateObject(Object obj, ResourceBundle rb) {
		try {
			Map map = convertBundleToMap(rb);

			BeanUtils.copyProperties(obj, map);
		} catch (Exception e) {
			e.printStackTrace();
			log.error("Exception occured populating object: " + e.getMessage());
		}

		return obj;
	}

	/**
	 * This method inspects a POJO or Form and figures out its pojo/form
	 * equivalent.
	 * 
	 * @param o
	 *            the object to inspect
	 * @return the Class of the persistable object
	 * @throws ClassNotFoundException
	 * @throws InstantiationException
	 * @throws IllegalAccessException
	 */
	public static Object getOpposingObject(Object o)
			throws ClassNotFoundException, InstantiationException,
			IllegalAccessException {
		String name = o.getClass().getName();

		if (o instanceof BaseObject) {
			if (log.isDebugEnabled()) {
				log.debug("getting form equivalent of pojo...");
			}

			name = StringUtils.replace(name, ".model.", ".webapp.form.");
			if (AopUtils.isCglibProxy(o)) {
				name = name.substring(0, name.indexOf("$$"));
			}
			name += "Form";
		} else {
			if (log.isDebugEnabled()) {
				log.debug("getting pojo equivalent of form...");
			}
			name = StringUtils.replace(name, ".webapp.form.", ".model.");
			name = name.substring(0, name.lastIndexOf("Form"));
		}

		Class obj = Class.forName(name);

		if (log.isDebugEnabled()) {
			log.debug("returning className: " + obj.getName());
		}

		return obj.newInstance();
	}

	/**
	 * Convenience method to convert a form to a POJO and back again
	 * 
	 * @param o
	 *            the object to tranfer properties from
	 * @return converted object
	 */
	public static Object convert(Object o) throws Exception {
		if (o == null) {
			return null;
		}
		Object target = getOpposingObject(o);
		BeanUtils.copyProperties(target, o);
		return target;
	}

	/**
	 * Convenience method to convert Lists (in a Form) from POJOs to Forms. Also
	 * checks for and formats dates.
	 * 
	 * @param o
	 * @return Object with converted lists
	 * @throws Exception
	 */
	public static Object convertLists(Object o) throws Exception {
		if (o == null) {
			return null;
		}

		Object target = null;

		PropertyDescriptor[] origDescriptors = PropertyUtils
				.getPropertyDescriptors(o);

		for (int i = 0; i < origDescriptors.length; i++) {
			String name = origDescriptors[i].getName();

			if (origDescriptors[i].getPropertyType().equals(List.class)) {
				List list = (List) PropertyUtils.getProperty(o, name);
				for (int j = 0; j < list.size(); j++) {
					Object origin = list.get(j);
					target = convert(origin);
					list.set(j, target);
				}
				PropertyUtils.setProperty(o, name, list);
			}
		}
		return o;
	}
}