/**
    * Copyright 2010-2012 The Kuali Foundation
    *
    * Licensed under the Educational Community License, Version 2.0 (the "License");
    * you may not use this file except in compliance with the License.
    * You may obtain a copy of the License at
    *
    * http://www.opensource.org/licenses/ecl2.php
    *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package org.kuali.common.util.spring;
  
  import java.util.ArrayList;
  import java.util.Collections;
  import java.util.List;
  import java.util.Map;
  import java.util.Properties;
  
  import org.kuali.common.util.Assert;
  import org.kuali.common.util.FormatUtils;
  import org.kuali.common.util.PropertyUtils;
  import org.kuali.common.util.property.ProjectProperties;
  import org.kuali.common.util.property.ProjectPropertiesComparator;
  import org.kuali.common.util.property.PropertiesLoaderContext;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  import org.springframework.beans.factory.FactoryBean;
  import org.springframework.util.CollectionUtils;
  
  /**
   * 
   */
  public class ProjectPropertiesLoaderFactoryBean implements FactoryBean<Properties> {
  
  	private static final Logger logger = LoggerFactory.getLogger(ProjectPropertiesLoaderFactoryBean.class);
  
  	List<String> locations;
  	boolean singleton = true;
  	ProjectPropertiesComparator comparator;
  
  	@Override
  	public Properties getObject() throws Exception {
  		Assert.isFalse(CollectionUtils.isEmpty(locations), "locations is empty");
  		long start = System.currentTimeMillis();
  		List<ProjectProperties> pps = new ArrayList<ProjectProperties>();
  		// Extract any ProjectProperties beans anywhere in the context
  		for (String location : locations) {
  			Map<String, ProjectProperties> beans = SpringUtils.getAllBeans(location, ProjectProperties.class);
  			logger.info("Located {} sets of project properties", beans.size());
  
  			List<ProjectProperties> list = new ArrayList<ProjectProperties>();
  			// Add them to a list
  			for (ProjectProperties bean : beans.values()) {
  				list.add(bean);
  			}
  			// Sort them by sequence (only relevant if there is more than one which there typically is not)
  			Collections.sort(list);
  			pps.addAll(list);
  		}
  
  		// Cycle through the list we have adding in properties as we go
  		Properties properties = new Properties();
  		for (ProjectProperties pp : pps) {
  			for (PropertiesLoaderContext ctx : pp.getLoaderContexts()) {
  				Properties combined = PropertyUtils.combine(properties, ctx.getProperties());
  				ctx.setProperties(combined);
  				Properties loaded = PropertyUtils.load(ctx);
  				properties.putAll(loaded);
  			}
  		}
  		String elapsed = FormatUtils.getTime(System.currentTimeMillis() - start);
  		logger.info("Loaded {} properties.  Total time: {}", properties.size(), elapsed);
  		return properties;
  	}
  
  	@Override
  	public Class<Properties> getObjectType() {
  		return Properties.class;
  	}
  
  	@Override
  	public boolean isSingleton() {
  		return singleton;
  	}
  
  	public void setSingleton(boolean singleton) {
  		this.singleton = singleton;
  	}
  
  	public List<String> getLocations() {
  		return locations;
  	}
  
  	public void setLocations(List<String> locations) {
 		this.locations = locations;
 	}
 
 	public ProjectPropertiesComparator getComparator() {
 		return comparator;
 	}
 
 	public void setComparator(ProjectPropertiesComparator comparator) {
 		this.comparator = comparator;
 	}
 
 }