/*!
 * This program is free software; you can redistribute it and/or modify it under the
 * terms of the GNU Lesser General Public License, version 2.1 as published by the Free Software
 * Foundation.
 *
 * You should have received a copy of the GNU Lesser General Public License along with this
 * program; if not, you can obtain a copy at http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html
 * or from the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
 * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU Lesser General Public License for more details.
 *
 * Copyright (c) 2002-2013 Pentaho Corporation..  All rights reserved.
 */

package org.pentaho.platform.web.http.context;

import org.pentaho.platform.engine.core.system.objfac.AbstractSpringPentahoObjectFactory;
import org.pentaho.platform.web.http.messages.Messages;
import org.springframework.web.context.support.WebApplicationContextUtils;
import org.springframework.web.context.support.XmlWebApplicationContext;

import javax.servlet.ServletContext;

/**
 * This factory implementation can be used in a web environment in which a Spring {@link WebApplicationContext} has
 * already been created during initialization of the web application. WebSpringPentahoObjectFactory will delegate object
 * creation and management to the Spring context. There is one exception to this rule: see
 * {@link AbstractSpringPentahoObjectFactory} for more details.
 * <p>
 * The Spring bean factory supports the binding of objects to particular scopes. See Spring documentation for
 * description of the scope types: singleton, prototype, session, and request. The latter two apply only in a web
 * context.
 * 
 * @author Aaron Phillips
 * @see AbstractSpringPentahoObjectFactory
 * @see http://static.springframework.org/spring/docs/2.5.x/reference/beans.html#beans-factory-scopes
 */
public class WebSpringPentahoObjectFactory extends AbstractSpringPentahoObjectFactory {

  public WebSpringPentahoObjectFactory() {
    super( "Main Object Factory" );
  }

  /**
   * Initializes this object factory by setting the internal bean factory to the {@link WebApplicationContext} instance
   * managed by Spring.
   * 
   * @param configFile
   *          ignored for this implementation
   * @param context
   *          the {@link ServletContext} under which this system is currently running. This is used to retrieve the
   *          Spring {@link WebApplicationContext}.
   * @throws IllegalArgumentException
   *           if context is not the correct type, only ServletContext is accepted
   */
  public void init( String configFile, Object context ) {
    if ( !( context instanceof ServletContext ) ) {
      String msg =
          Messages.getInstance().getErrorString( "WebSpringPentahoObjectFactory.ERROR_0001_CONTEXT_NOT_SUPPORTED", //$NON-NLS-1$
              ServletContext.class.getName(), context.getClass().getName() );
      throw new IllegalArgumentException( msg );
    }

    ServletContext servletContext = (ServletContext) context;

    beanFactory =
        (XmlWebApplicationContext) WebApplicationContextUtils.getRequiredWebApplicationContext( servletContext );
  }
}