/**
    *    Copyright 2009-2016 the original author or authors.
    *
    *    Licensed under the Apache 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.apache.org/licenses/LICENSE-2.0
    *
   *    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.apache.ibatis.datasource.jndi;
  
  import java.util.Map.Entry;
  import java.util.Properties;
  
  import javax.naming.Context;
  import javax.naming.InitialContext;
  import javax.naming.NamingException;
  import javax.sql.DataSource;
  
  import org.apache.ibatis.datasource.DataSourceException;
  import org.apache.ibatis.datasource.DataSourceFactory;
  
  /**
   * @author Clinton Begin
   */
  public class JndiDataSourceFactory implements DataSourceFactory {
  
    public static final String INITIAL_CONTEXT = "initial_context";
    public static final String DATA_SOURCE = "data_source";
    public static final String ENV_PREFIX = "env.";
  
    private DataSource dataSource;
  
    @Override
    public void setProperties(Properties properties) {
      try {
        InitialContext initCtx;
        Properties env = getEnvProperties(properties);
        if (env == null) {
          initCtx = new InitialContext();
        } else {
          initCtx = new InitialContext(env);
        }
  
        if (properties.containsKey(INITIAL_CONTEXT)
            && properties.containsKey(DATA_SOURCE)) {
          Context ctx = (Context) initCtx.lookup(properties.getProperty(INITIAL_CONTEXT));
          dataSource = (DataSource) ctx.lookup(properties.getProperty(DATA_SOURCE));
        } else if (properties.containsKey(DATA_SOURCE)) {
          dataSource = (DataSource) initCtx.lookup(properties.getProperty(DATA_SOURCE));
        }
  
      } catch (NamingException e) {
        throw new DataSourceException("There was an error configuring JndiDataSourceTransactionPool. Cause: " + e, e);
      }
    }
  
    @Override
    public DataSource getDataSource() {
      return dataSource;
    }
  
    private static Properties getEnvProperties(Properties allProps) {
      final String PREFIX = ENV_PREFIX;
      Properties contextProperties = null;
      for (Entry<Object, Object> entry : allProps.entrySet()) {
        String key = (String) entry.getKey();
        String value = (String) entry.getValue();
        if (key.startsWith(PREFIX)) {
          if (contextProperties == null) {
            contextProperties = new Properties();
          }
          contextProperties.put(key.substring(PREFIX.length()), value);
        }
      }
      return contextProperties;
    }
  
  }