/**
    * Copyright 2010-2014 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.property.processor;
  
  import java.util.HashMap;
  import java.util.Map;
  import java.util.Properties;
  
  import org.kuali.common.util.Mode;
  import org.kuali.common.util.PropertyUtils;
  import org.kuali.common.util.property.Constants;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  import org.springframework.util.Assert;
  
  public class JdbcUrlProcessor implements PropertyProcessor {
  	private static final Logger logger = LoggerFactory.getLogger(JdbcUrlProcessor.class);
  
  	String jdbcUrlProperty = "jdbc.url";
  	String dbVendorProperty = "db.vendor";
  	Map<String, String> jdbcUrlFragments = getJdbcUrlFragments();
  	Mode propertyOverwriteMode = Constants.DEFAULT_PROPERTY_OVERWRITE_MODE;
  
  	@Override
  	public void process(Properties properties) {
  		Assert.notNull(jdbcUrlProperty);
  		Assert.notNull(dbVendorProperty);
  		String jdbcUrl = properties.getProperty(jdbcUrlProperty);
  		if (jdbcUrl == null) {
  			logger.info(jdbcUrlProperty + " is not set");
  			return;
  		}
  		String databaseVendor = getMatch(jdbcUrl, jdbcUrlFragments);
  		if (databaseVendor != null) {
  			PropertyUtils.addOrOverrideProperty(properties, dbVendorProperty, databaseVendor, propertyOverwriteMode);
  		} else {
  			logger.info("Could not identify a database vendor from url - [{}]", jdbcUrl);
  		}
  	}
  
  	/**
  	 * Loop through <code>fragments.keySet()</code> to see if <code>string</code> contains any of the <code>fragments</code>. If there is a
  	 * match with a <code>fragment</code>, return the corresponding value for the <code>fragment</code> from the map.
  	 */
  	protected String getMatch(String string, Map<String, String> fragments) {
  		for (String fragment : fragments.keySet()) {
  			if (string.contains(fragment)) {
  				return fragments.get(fragment);
  			}
  		}
  		return null;
  	}
  
  	protected Map<String, String> getJdbcUrlFragments() {
  		Map<String, String> m = new HashMap<String, String>();
  		m.put(":hsqldb:", "hsql");
  		m.put(":derby:", "derby");
  		m.put(":postgresql:", "postgresql");
  		m.put(":db2:", "db2");
  		m.put(":mysql:", "mysql");
  		m.put(":oracle:", "oracle");
  		m.put(":h2:", "h2");
  		return m;
  	}
  
  }