/**
    * Copyright 2004-2012 The Kuali Foundation
    *
    * Licensed under the Educational Community 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.opensource.org/licenses/ecl2.php
    *
   * 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.torque.mojo;
  
  import java.io.File;
  import java.util.Iterator;
  import java.util.Map;
  
  import org.apache.commons.configuration.ConfigurationException;
  import org.apache.commons.configuration.FileConfiguration;
  import org.apache.commons.configuration.PropertiesConfiguration;
  import org.apache.maven.plugin.MojoExecutionException;
  import org.apache.texen.ant.TexenTask;
  
  /**
   * The base class for mojos that wrap Texen Ant Tasks
   */
  public abstract class TexenTaskMojo extends AntTaskMojo {
  	/**
  	 * The directory where the generator output is written
  	 * 
  	 * @required
  	 */
  	private String outputDir;
  
  	/**
  	 * The base path where the templates are read from, if they are not read from the classpath.
  	 * 
  	 * @parameter expression="${templatePath}" default-value="${basedir}/src/main/impex/templates"
  	 */
  	private String templatePath;
  
  	/**
  	 * Whether the templates should be loaded from the classpath.
  	 * 
  	 * @parameter expression="${useClasspath}" default-value="true"
  	 */
  	private boolean useClasspath;
  
  	/**
  	 * A map where all user-defined context properties can be set. Overrides all other mojo configuration settings which
  	 * are mapped to context properties.
  	 * 
  	 * @parameter
  	 */
  	private Map<?, ?> userContextProperties;
  
  	/**
  	 * The path to the generated context property file.
  	 * 
  	 * @required
  	 */
  	private String contextPropertiesPath;
  
  	/**
  	 * Sets the path to Torque's output directory.
  	 * 
  	 * @param outputDir
  	 *            the path to Torque's output directory.
  	 */
  	public void setOutputDir(String outputDir) {
  		this.outputDir = outputDir;
  	}
  
  	/**
  	 * Returns the path to Torque's output directory.
  	 * 
  	 * @return the path to Torque's output directory. Not null if initialized correctly.
  	 */
  	public String getOutputDir() {
  		return this.outputDir;
  	}
  
  	/**
  	 * Sets the path to Torque's templates, if the classpath is not used to load the templates.
  	 * 
  	 * @param templatePath
  	 *            the path to Torque's templates.
  	 */
  	public void setTemplatePath(String templatePath) {
  		this.templatePath = templatePath;
  	}
  
  	/**
  	 * Returns the path to Torque's templates, if the classpath is not used to load the templates.
  	 * 
 	 * @return the path to Torque's templates.
 	 */
 	public String getTemplatePath() {
 		return this.templatePath;
 	}
 
 	/**
 	 * Sets whether the classpath should be used to locate the templates.
 	 * 
 	 * @param templatePath
 	 *            the path to Torque's templates.
 	 */
 	public void setUseClasspath(boolean useClasspath) {
 		this.useClasspath = useClasspath;
 	}
 
 	/**
 	 * Returns whether the classpath is used to locate the templates.
 	 * 
 	 * @return true if the classpath is used to locate the templates, false otherwise
 	 */
 	public boolean getUseClasspath() {
 		return this.useClasspath;
 	}
 
 	/**
 	 * Sets the path to the generated property file used as Texen's context properties.
 	 * 
 	 * @param generatedPropertyFilePath
 	 *            the path to the generated context properties file.
 	 */
 	public void setContextPropertiesPath(String contextPropertiesPath) {
 		this.contextPropertiesPath = contextPropertiesPath;
 	}
 
 	/**
 	 * Returns the path to the generated property file used as Texen's context properties.
 	 * 
 	 * @return the path to the generated context properties file.
 	 */
 	public String getContextPropertiesPath() {
 		return this.contextPropertiesPath;
 	}
 
 	/**
 	 * Sets the map which defines user-defined context properties. The settings override all other mojo configuration
 	 * settings which are mapped to context properties.
 	 * 
 	 * @param contextProperties
 	 *            the user-defined context properties.
 	 */
 	public void setUserContextProperties(Map<?, ?> userContextProperties) {
 		this.userContextProperties = userContextProperties;
 	}
 
 	/**
 	 * Returns the map which defines user-defined context properties.
 	 * 
 	 * @return the map containing user-defined context properties, or null if not set.
 	 */
 	public Map<?, ?> getUserContextProperties() {
 		return userContextProperties;
 	}
 
 	/**
 	 * returns the generator Task for this mojo.
 	 * 
 	 * @return the generator Task, not null.
 	 */
 	protected TexenTask getGeneratorTask() {
 		return (TexenTask) getAntTask();
 	}
 
 	/**
 	 * Generates the context properties file for Texen. The file is written to the path contextPropertiesPath.
 	 * 
 	 * @throws MojoExecutionException
 	 *             if an error occurs.
 	 */
 	protected void generateContextProperties() throws MojoExecutionException {
 		try {
 			FileConfiguration configuration = getMojoContextProperties();
 			if (userContextProperties != null) {
 				for (Iterator<?> contextPropertyIt = userContextProperties.entrySet().iterator(); contextPropertyIt.hasNext();) {
 					Map.Entry<?, ?> entry = (Map.Entry<?, ?>) contextPropertyIt.next();
 					configuration.addProperty(entry.getKey().toString(), entry.getValue().toString());
 				}
 			}
 			configuration.save(contextPropertiesPath);
 		} catch (ConfigurationException e) {
 			getLog().error("Error writing temporary context properties: " + e.getMessage());
 			throw new MojoExecutionException(e.getMessage());
 		}
 	}
 
 	/**
 	 * Configures the Texen task wrapped by this mojo.
 	 */
 	protected void configureTask() throws MojoExecutionException {
 		super.configureTask();
 		TexenTask task = getGeneratorTask();
 		task.setContextProperties(contextPropertiesPath);
 		task.setUseClasspath(useClasspath);
 		try {
 			task.setTemplatePath(templatePath);
 		} catch (Exception e) {
 			throw new MojoExecutionException("Error setting template path", e);
 		}
 
 		File outputDirectory = new File(outputDir);
 		outputDirectory.mkdirs();
 		getGeneratorTask().setOutputDirectory(outputDirectory);
 	}
 
 	/**
 	 * Executes the wrapped Texen task. Before this is done, the context properties file is generated and the Texen task
 	 * is configured.
 	 * 
 	 * @throws MojoExecutionException
 	 *             if an error occurs during execution.
 	 * 
 	 * @see org.apache.maven.plugin.Mojo#execute()
 	 */
 	public void executeMojo() throws MojoExecutionException {
 		generateContextProperties();
 		super.executeMojo();
 	}
 
 	/**
 	 * Returns the context properties for the Texen task which are defined in the configuration of the child mojo. This
 	 * method needs to be overwritten in subclasses.
 	 * 
 	 * @return The PropertiesConfiguration containing all context properties, not null.
 	 */
 	protected abstract PropertiesConfiguration getMojoContextProperties();
 }