/*
    * Copyright 2006-2011 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.core.job.builder;
  
  import java.util.ArrayList;
  import java.util.LinkedHashSet;
  import java.util.List;
  import java.util.Set;
  
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  import org.springframework.batch.core.Job;
  import org.springframework.batch.core.JobExecutionListener;
  import org.springframework.batch.core.JobParametersIncrementer;
  import org.springframework.batch.core.JobParametersValidator;
  import org.springframework.batch.core.job.AbstractJob;
  import org.springframework.batch.core.repository.JobRepository;
  
  /**
   * A base class and utility for other job builders providing access to common properties like job repository.
   * 
   * @author Dave Syer
   * 
   * @since 2.2
   */
  public abstract class JobBuilderHelper<B extends JobBuilderHelper<B>> {
  
  	protected final Log logger = LogFactory.getLog(getClass());
  
  	private final CommonStepProperties properties;
  
  	public JobBuilderHelper(String name) {
  		this.properties = new CommonStepProperties();
  		properties.name = name;
  	}
  
  	/**
  	 * Create a new builder initialized with any properties in the parent. The parent is copied, so it can be re-used.
  	 * 
  	 * @param parent a parent helper containing common step properties
  	 */
  	protected JobBuilderHelper(JobBuilderHelper<?> parent) {
  		this.properties = new CommonStepProperties(parent.properties);
  	}
  
  	/**
  	 * Add a job parameters validator.
  	 * 
  	 * @param jobParametersValidator a job parameters validator
  	 * @return this to enable fluent chaining
  	 */
  	public B validator(JobParametersValidator jobParametersValidator) {
  		properties.jobParametersValidator = jobParametersValidator;
  		@SuppressWarnings("unchecked")
  		B result = (B) this;
  		return result;
  	}
  
  	/**
  	 * Add a job parameters incrementer.
  	 * 
  	 * @param jobParametersIncrementer a job parameters incrementer
  	 * @return this to enable fluent chaining
  	 */
  	public B incrementer(JobParametersIncrementer jobParametersIncrementer) {
  		properties.jobParametersIncrementer = jobParametersIncrementer;
  		@SuppressWarnings("unchecked")
  		B result = (B) this;
  		return result;
  	}
  
  	/**
  	 * Sets the job repository for the job.
  	 * 
  	 * @param jobRepository the job repository (mandatory)
  	 * @return this to enable fluent chaining
  	 */
  	public B repository(JobRepository jobRepository) {
  		properties.jobRepository = jobRepository;
  		@SuppressWarnings("unchecked")
  		B result = (B) this;
  		return result;
  	}
  
  	/**
  	 * Register a job execution listener.
 	 * 
 	 * @param listener a job execution listener
 	 * @return this to enable fluent chaining
 	 */
 	public B listener(JobExecutionListener listener) {
 		properties.addJobExecutionListener(listener);
 		@SuppressWarnings("unchecked")
 		B result = (B) this;
 		return result;
 	}
 
 	/**
 	 * Set a flag to prevent restart an execution of this job even if it has failed.
 	 * 
 	 * @return this to enable fluent chaining
 	 */
 	public B preventRestart() {
 		properties.restartable = false;
 		@SuppressWarnings("unchecked")
 		B result = (B) this;
 		return result;
 	}
 
 	protected String getName() {
 		return properties.name;
 	}
 
 	protected JobRepository getJobRepository() {
 		return properties.jobRepository;
 	}
 
 	protected boolean isRestartable() {
 		return properties.restartable;
 	}
 
 	protected void enhance(Job target) {
 
 		if (target instanceof AbstractJob) {
 
 			AbstractJob job = (AbstractJob) target;
 			job.setJobRepository(properties.getJobRepository());
 
 			JobParametersIncrementer jobParametersIncrementer = properties.getJobParametersIncrementer();
 			if (jobParametersIncrementer != null) {
 				job.setJobParametersIncrementer(jobParametersIncrementer);
 			}
 			JobParametersValidator jobParametersValidator = properties.getJobParametersValidator();
 			if (jobParametersValidator != null) {
 				job.setJobParametersValidator(jobParametersValidator);
 			}
 
 			Boolean restartable = properties.getRestartable();
 			if (restartable != null) {
 				job.setRestartable(restartable);
 			}
 
 			List<JobExecutionListener> listeners = properties.getJobExecutionListeners();
 			if (!listeners.isEmpty()) {
 				job.setJobExecutionListeners(listeners.toArray(new JobExecutionListener[0]));
 			}
 
 		}
 
 	}
 
 	public static class CommonStepProperties {
 
 		private Set<JobExecutionListener> jobExecutionListeners = new LinkedHashSet<JobExecutionListener>();
 
 		private boolean restartable = true;
 
 		private JobRepository jobRepository;
 
 		private JobParametersIncrementer jobParametersIncrementer;
 
 		private JobParametersValidator jobParametersValidator;
 
 		public CommonStepProperties() {
 		}
 
 		public CommonStepProperties(CommonStepProperties properties) {
 			this.name = properties.name;
 			this.restartable = properties.restartable;
 			this.jobRepository = properties.jobRepository;
 		}
 
 		public JobParametersIncrementer getJobParametersIncrementer() {
 			return jobParametersIncrementer;
 		}
 
 		public void setJobParametersIncrementer(JobParametersIncrementer jobParametersIncrementer) {
 			this.jobParametersIncrementer = jobParametersIncrementer;
 		}
 
 		public JobParametersValidator getJobParametersValidator() {
 			return jobParametersValidator;
 		}
 
 		public void setJobParametersValidator(JobParametersValidator jobParametersValidator) {
 			this.jobParametersValidator = jobParametersValidator;
 		}
 
 		public JobRepository getJobRepository() {
 			return jobRepository;
 		}
 
 		public void setJobRepository(JobRepository jobRepository) {
 			this.jobRepository = jobRepository;
 		}
 
 		public String getName() {
 			return name;
 		}
 
 		public void setName(String name) {
 			this.name = name;
 		}
 
 		public List<JobExecutionListener> getJobExecutionListeners() {
 			return new ArrayList<JobExecutionListener>(jobExecutionListeners);
 		}
 
 		public void addStepExecutionListeners(List<JobExecutionListener> jobExecutionListeners) {
 			this.jobExecutionListeners.addAll(jobExecutionListeners);
 		}
 
 		public void addJobExecutionListener(JobExecutionListener jobExecutionListener) {
 			this.jobExecutionListeners.add(jobExecutionListener);
 		}
 
 		public boolean getRestartable() {
 			return restartable;
 		}
 
 		public void setRestartable(boolean restartable) {
 			this.restartable = restartable;
 		}
 
 		private String name;
 
 	}
 
 }