/*
 * JBoss, Home of Professional Open Source.
 * Copyright 2008, Red Hat Middleware LLC, and individual contributors
 * as indicated by the @author tags. See the copyright.txt file in the
 * distribution for a full listing of individual contributors.
 *
 * This is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation; either version 2.1 of
 * the License, or (at your option) any later version.
 *
 * This software 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.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this software; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
 */
package org.jboss.ejb.plugins.cmp.jdbc.keygen;

import java.sql.PreparedStatement;
import java.sql.SQLException;
import java.sql.Statement;
import java.lang.reflect.Method;
import java.lang.reflect.InvocationTargetException;

import javax.ejb.EJBException;

import org.jboss.ejb.plugins.cmp.jdbc.JDBCIdentityColumnCreateCommand;
import org.jboss.ejb.plugins.cmp.jdbc.JDBCStoreManager;
import org.jboss.ejb.plugins.cmp.jdbc.metadata.JDBCEntityCommandMetaData;
import org.jboss.ejb.EntityEnterpriseContext;
import org.jboss.deployment.DeploymentException;

/**
 * Create command for Informix that uses the driver's getSerial method
 * to retrieve SERIAL values. Also supports SERIAL8 columns if method
 * attribute of entity-command is set to "getSerial8"
 *
 * @author <a href="mailto:jeremy@boynes.com">Jeremy Boynes</a>
 * @author Scott.Stark@jboss.org
 * @version $Revision: 81030 $
 */
public class JDBCInformixCreateCommand extends JDBCIdentityColumnCreateCommand
{
   private static final String NAME = "class-name";
   private static final String DEFAULT_CLASS = "com.informix.jdbc.IfxStatement";
   private static final String METHOD = "method";
   private static final String DEFAULT_METHOD = "getSerial";

   private String className;
   private String methodName;
   private Method method;
   private Method getUnderlyingStatement;

   public void init(JDBCStoreManager manager) throws DeploymentException
   {
      super.init(manager);
      ClassLoader loader = GetTCLAction.getContextClassLoader();
      try
      {
         Class psClass = loader.loadClass(className);
         method = psClass.getMethod(methodName, null);
      }
      catch(ClassNotFoundException e)
      {
         throw new DeploymentException("Could not load driver class: " + className, e);
      }
      catch(NoSuchMethodException e)
      {
         throw new DeploymentException("Driver does not have method: " + methodName + "()");
      }

      try
      {
         Class wrapperClass = loader.loadClass("org.jboss.resource.adapter.jdbc.StatementAccess");
         getUnderlyingStatement = wrapperClass.getMethod("getUnderlyingStatement", null);
      }
      catch (ClassNotFoundException e)
      {
         throw new DeploymentException("Could not load org.jboss.resource.adapter.jdbc.StatementAccess", e);
      }
      catch (NoSuchMethodException e)
      {
         throw new DeploymentException("StatementAccess.getUnderlyingStatement not found", e);
      }
   }

   protected void initEntityCommand(JDBCEntityCommandMetaData entityCommand) throws DeploymentException
   {
      super.initEntityCommand(entityCommand);
      className = entityCommand.getAttribute(NAME);
      if(className == null)
      {
         className = DEFAULT_CLASS;
      }
      methodName = entityCommand.getAttribute(METHOD);
      if(methodName == null)
      {
         methodName = DEFAULT_METHOD;
      }
   }

   protected int executeInsert(int paramIndex, PreparedStatement ps, EntityEnterpriseContext ctx) throws SQLException
   {
      int rows = ps.executeUpdate();

      // remove any JCA wrappers
      Statement stmt = ps;
      do
      {
         try
         {
            Object[] args = {};
            stmt = (Statement) getUnderlyingStatement.invoke(stmt, args);
         }
         catch (IllegalAccessException e)
         {
            SQLException ex = new SQLException("Failed to invoke getUnderlyingStatement");
            ex.initCause(e);
            throw ex;
         }
         catch (InvocationTargetException e)
         {
            SQLException ex = new SQLException("Failed to invoke getUnderlyingStatement");
            ex.initCause(e);
            throw ex;
         }
      } while (stmt != null && method.getDeclaringClass().isInstance(stmt) == false);

      try
      {
         Number pk = (Number)method.invoke(stmt, null);
         pkField.setInstanceValue(ctx, pk);
         return rows;
      }
      catch(RuntimeException e)
      {
         throw e;
      }
      catch(Exception e)
      {
         // throw EJBException to force a rollback as the row has been inserted
         throw new EJBException("Error extracting generated keys", e);
      }
   }
}