/*
    * Copyright 2009-2014 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.springframework.batch.admin.service;
  
  import static org.springframework.batch.support.DatabaseType.SYBASE;
  
  import java.sql.Types;
  
  import javax.sql.DataSource;
  
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  
  import org.springframework.batch.core.configuration.JobLocator;
  import org.springframework.batch.core.configuration.ListableJobLocator;
  import org.springframework.batch.core.explore.JobExplorer;
  import org.springframework.batch.core.jsr.JsrJobParametersConverter;
  import org.springframework.batch.core.jsr.launch.JsrJobOperator;
  import org.springframework.batch.core.launch.JobLauncher;
  import org.springframework.batch.core.repository.ExecutionContextSerializer;
  import org.springframework.batch.core.repository.JobRepository;
  import org.springframework.batch.core.repository.dao.AbstractJdbcBatchMetadataDao;
  import org.springframework.batch.core.repository.dao.ExecutionContextDao;
  import org.springframework.batch.core.repository.dao.JdbcExecutionContextDao;
  import org.springframework.batch.core.repository.dao.JdbcJobExecutionDao;
  import org.springframework.batch.core.repository.dao.JdbcStepExecutionDao;
  import org.springframework.batch.core.repository.dao.XStreamExecutionContextStringSerializer;
  import org.springframework.batch.item.database.support.DataFieldMaxValueIncrementerFactory;
  import org.springframework.batch.item.database.support.DefaultDataFieldMaxValueIncrementerFactory;
  import org.springframework.batch.support.DatabaseType;
  import org.springframework.beans.factory.FactoryBean;
  import org.springframework.beans.factory.InitializingBean;
  import org.springframework.jdbc.core.JdbcOperations;
  import org.springframework.jdbc.core.JdbcTemplate;
  import org.springframework.jdbc.support.lob.DefaultLobHandler;
  import org.springframework.jdbc.support.lob.LobHandler;
  import org.springframework.transaction.PlatformTransactionManager;
  import org.springframework.util.Assert;
  import org.springframework.util.StringUtils;
  
  /**
   * A factory for a {@link JobService} that makes the configuration of its
   * various ingredients as convenient as possible.
   * 
   * @author Dave Syer
   * 
   */
  public class SimpleJobServiceFactoryBean implements FactoryBean<JobService>, InitializingBean {
  	private static final Log logger = LogFactory.getLog(SimpleJobServiceFactoryBean.class);
  
  	private DataSource dataSource;
  
  	private JdbcOperations jdbcTemplate;
  
  	private String databaseType;
  
  	private String tablePrefix = AbstractJdbcBatchMetadataDao.DEFAULT_TABLE_PREFIX;
  
  	private DataFieldMaxValueIncrementerFactory incrementerFactory;
  
  	private int maxVarCharLength = AbstractJdbcBatchMetadataDao.DEFAULT_EXIT_MESSAGE_LENGTH;
  
  	private LobHandler lobHandler;
  
  	private JobRepository jobRepository;
  
  	private JobLauncher jobLauncher;
  
  	private ListableJobLocator jobLocator;
  
  	private JobExplorer jobExplorer;
  
  	private ExecutionContextSerializer serializer;
  
  	private PlatformTransactionManager transactionManager;
  
  	public void setTransactionManager(PlatformTransactionManager transactionManager) {
  		this.transactionManager = transactionManager;
  	}
  
  	/**
  	 * A special handler for large objects. The default is usually fine, except
  	 * for some (usually older) versions of Oracle. The default is determined
  	 * from the data base type.
  	 * 
  	 * @param lobHandler the {@link LobHandler} to set
 	 * 
 	 * @see LobHandler
 	 */
 	public void setLobHandler(LobHandler lobHandler) {
 		this.lobHandler = lobHandler;
 	}
 
 	/**
 	 * Public setter for the length of long string columns in database. Do not
 	 * set this if you haven't modified the schema. Note this value will be used
 	 * for the exit message in both {@link JdbcJobExecutionDao} and
 	 * {@link JdbcStepExecutionDao} and also the short version of the execution
 	 * context in {@link JdbcExecutionContextDao} . For databases with
 	 * multi-byte character sets this number can be smaller (by up to a factor
 	 * of 2 for 2-byte characters) than the declaration of the column length in
 	 * the DDL for the tables.
 	 * 
 	 * @param maxVarCharLength the exitMessageLength to set
 	 */
 	public void setMaxVarCharLength(int maxVarCharLength) {
 		this.maxVarCharLength = maxVarCharLength;
 	}
 
 	/**
 	 * Public setter for the {@link DataSource}.
 	 * @param dataSource a {@link DataSource}
 	 */
 	public void setDataSource(DataSource dataSource) {
 		this.dataSource = dataSource;
 	}
 
 	/**
 	 * Sets the database type.
 	 * @param dbType as specified by
 	 * {@link DefaultDataFieldMaxValueIncrementerFactory}
 	 */
 	public void setDatabaseType(String dbType) {
 		this.databaseType = dbType;
 	}
 
 	/**
 	 * Sets the table prefix for all the batch meta-data tables.
 	 * @param tablePrefix Prefix for batch meta-data tables
 	 */
 	public void setTablePrefix(String tablePrefix) {
 		this.tablePrefix = tablePrefix;
 	}
 
 	/**
 	 * A factory for incrementers (used to build primary keys for meta data).
 	 * Defaults to {@link DefaultDataFieldMaxValueIncrementerFactory}.
 	 * @param incrementerFactory the incrementer factory to set
 	 */
 	public void setIncrementerFactory(DataFieldMaxValueIncrementerFactory incrementerFactory) {
 		this.incrementerFactory = incrementerFactory;
 	}
 
 	public void setJobExplorer(JobExplorer jobExplorer) {
 		this.jobExplorer = jobExplorer;
 	}
 
 	/**
 	 * The repository used to store and update jobs and step executions.
 	 * 
 	 * @param jobRepository the {@link JobRepository} to set
 	 */
 	public void setJobRepository(JobRepository jobRepository) {
 		this.jobRepository = jobRepository;
 	}
 
 	/**
 	 * The launcher used to run jobs.
 	 * @param jobLauncher a {@link JobLauncher}
 	 */
 	public void setJobLauncher(JobLauncher jobLauncher) {
 		this.jobLauncher = jobLauncher;
 	}
 
 	/**
 	 * A registry that can be used to locate jobs to run.
 	 * @param jobLocator a {@link JobLocator}
 	 */
 	public void setJobLocator(ListableJobLocator jobLocator) {
 		this.jobLocator = jobLocator;
 	}
 
 	/**
 	 * A custom implementation of the {@link ExecutionContextSerializer}. The
 	 * default, if not injected, is the
 	 * {@link XStreamExecutionContextStringSerializer}.
 	 * 
 	 * @param serializer
 	 *            the serializer to set
 	 * @see ExecutionContextSerializer
 	 */
 	public void setSerializer(ExecutionContextSerializer serializer) {
 		this.serializer = serializer;
 	}
 
 	public void afterPropertiesSet() throws Exception {
 
 		Assert.notNull(dataSource, "DataSource must not be null.");
 		Assert.notNull(jobRepository, "JobRepository must not be null.");
 		Assert.notNull(jobLocator, "JobLocator must not be null.");
 		Assert.notNull(jobLauncher, "JobLauncher must not be null.");
 		Assert.notNull(jobExplorer, "JobExplorer must not be null.");
 
 		jdbcTemplate = new JdbcTemplate(dataSource);
 
 		if (incrementerFactory == null) {
 			incrementerFactory = new DefaultDataFieldMaxValueIncrementerFactory(dataSource);
 		}
 
 		if (databaseType == null) {
 			databaseType = DatabaseType.fromMetaData(dataSource).name();
 			logger.info("No database type set, using meta data indicating: " + databaseType);
 		}
 
 		if (lobHandler == null) {
 			lobHandler = new DefaultLobHandler();
 		}
 
 		if (serializer == null) {
 			XStreamExecutionContextStringSerializer defaultSerializer = new XStreamExecutionContextStringSerializer();
 			defaultSerializer.afterPropertiesSet();
 
 			serializer = defaultSerializer;
 		}
 
 		Assert.isTrue(incrementerFactory.isSupportedIncrementerType(databaseType), "'" + databaseType
 				+ "' is an unsupported database type.  The supported database types are "
 				+ StringUtils.arrayToCommaDelimitedString(incrementerFactory.getSupportedIncrementerTypes()));
 
 	}
 
 	protected SearchableJobInstanceDao createJobInstanceDao() throws Exception {
 		JdbcSearchableJobInstanceDao dao = new JdbcSearchableJobInstanceDao();
 		dao.setJdbcTemplate(jdbcTemplate);
 		dao.setJobIncrementer(incrementerFactory.getIncrementer(databaseType, tablePrefix + "JOB_SEQ"));
 		dao.setTablePrefix(tablePrefix);
 		dao.afterPropertiesSet();
 		return dao;
 	}
 
 	protected SearchableJobExecutionDao createJobExecutionDao() throws Exception {
 		JdbcSearchableJobExecutionDao dao = new JdbcSearchableJobExecutionDao();
 		dao.setDataSource(dataSource);
 		dao.setJobExecutionIncrementer(incrementerFactory.getIncrementer(databaseType, tablePrefix
 				+ "JOB_EXECUTION_SEQ"));
 		dao.setTablePrefix(tablePrefix);
 		dao.setClobTypeToUse(determineClobTypeToUse(this.databaseType));
 		dao.setExitMessageLength(maxVarCharLength);
 		dao.afterPropertiesSet();
 		return dao;
 	}
 
 	protected SearchableStepExecutionDao createStepExecutionDao() throws Exception {
 		JdbcSearchableStepExecutionDao dao = new JdbcSearchableStepExecutionDao();
 		dao.setDataSource(dataSource);
 		dao.setStepExecutionIncrementer(incrementerFactory.getIncrementer(databaseType, tablePrefix
 				+ "STEP_EXECUTION_SEQ"));
 		dao.setTablePrefix(tablePrefix);
 		dao.setClobTypeToUse(determineClobTypeToUse(this.databaseType));
 		dao.setExitMessageLength(maxVarCharLength);
 		dao.afterPropertiesSet();
 		return dao;
 	}
 
 	protected ExecutionContextDao createExecutionContextDao() throws Exception {
 		JdbcExecutionContextDao dao = new JdbcExecutionContextDao();
 		dao.setJdbcTemplate(jdbcTemplate);
 		dao.setTablePrefix(tablePrefix);
 		dao.setClobTypeToUse(determineClobTypeToUse(this.databaseType));
 		if (lobHandler != null) {
 			dao.setLobHandler(lobHandler);
 		}
 		dao.setSerializer(serializer);
 		dao.afterPropertiesSet();
 		// Assume the same length.
 		dao.setShortContextLength(maxVarCharLength);
 		return dao;
 	}
 
 	private int determineClobTypeToUse(String databaseType) {
 		if (SYBASE == DatabaseType.valueOf(databaseType.toUpperCase())) {
 			return Types.LONGVARCHAR;
 		}
 		else {
 			return Types.CLOB;
 		}
 	}
 
 	/**
 	 * Create a {@link SimpleJobService} from the configuration provided.
 	 * 
 	 * @see FactoryBean#getObject()
 	 */
 	public JobService getObject() throws Exception {
 		JsrJobParametersConverter jobParametersConverter = new JsrJobParametersConverter(dataSource);
 		jobParametersConverter.afterPropertiesSet();
 		JsrJobOperator jsrJobOperator = new JsrJobOperator(jobExplorer, jobRepository, jobParametersConverter, transactionManager);
 		jsrJobOperator.afterPropertiesSet();
 		return new SimpleJobService(createJobInstanceDao(), createJobExecutionDao(), createStepExecutionDao(),
 				jobRepository, jobLauncher, jobLocator, createExecutionContextDao(), jsrJobOperator);
 	}
 
 	/**
 	 * Tells the containing bean factory what kind of object is the product of
 	 * {@link #getObject()}.
 	 * 
 	 * @return SimpleJobService
 	 * @see FactoryBean#getObjectType()
 	 */
 	public Class<? extends JobService> getObjectType() {
 		return SimpleJobService.class;
 	}
 
 	/**
 	 * Allows optimisation in the containing bean factory.
 	 * 
 	 * @return true
 	 * @see FactoryBean#isSingleton()
 	 */
 	public boolean isSingleton() {
 		return true;
 	}
 
 }