package org.apache.maven.plugin.pmd;

 /*

  * Licensed to the Apache Software Foundation (ASF) under one

  * or more contributor license agreements.  See the NOTICE file

  * distributed with this work for additional information

  * regarding copyright ownership.  The ASF licenses this file

  * to you 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.

  */

 import java.io.BufferedReader;

 import java.io.File;

 import java.io.FileReader;

 import java.io.IOException;

 import java.util.ArrayList;

 import java.util.HashMap;

 import java.util.Iterator;

 import java.util.List;

 import java.util.Map;

 import org.apache.maven.plugin.AbstractMojo;

 import org.apache.maven.plugin.MojoExecutionException;

 import org.apache.maven.plugin.MojoFailureException;

 import org.apache.maven.project.MavenProject;

 import org.codehaus.plexus.util.xml.pull.MXParser;

 import org.codehaus.plexus.util.xml.pull.XmlPullParser;

 import org.codehaus.plexus.util.xml.pull.XmlPullParserException;

 /**

  * Base class for mojos that check if there were any PMD violations.

  * 

  * @author <a href="mailto:brett@apache.org">Brett Porter</a>

  */

 public abstract class AbstractPmdViolationCheckMojo

     extends AbstractMojo

 {

     private static final Boolean FAILURES_KEY = Boolean.TRUE;

     private static final Boolean WARNINGS_KEY = Boolean.FALSE;

     /**

      * The location of the XML report to check, as generated by the PMD report.

      * 

      * @parameter expression="${project.build.directory}"

      * @required

      */

     private File targetDirectory;

     /**

      * Whether to fail the build if the validation check fails.

      * 

      * @parameter expression="${pmd.failOnViolation}" default-value="true"

      * @required

      */

     private boolean failOnViolation;

     /**

      * The project language, for determining whether to run the report.

      * 

      * @parameter expression="${project.artifact.artifactHandler.language}"

      * @required

      * @readonly

      */

     private String language;

     /**

      * Whether to build an aggregated report at the root, or build individual reports.

      *

      * @parameter expression="${aggregate}" default-value="false"

      * @since 2.2

      */

     protected boolean aggregate;

     /**

      * Print details of check failures to build output.

      * 

      * @parameter expression="${pmd.verbose}" default-value="false"

      */

     private boolean verbose;

     /**

      * The project to analyse.

      *

      * @parameter expression="${project}"

      * @required

      * @readonly

      */

     protected MavenProject project;

     protected void executeCheck( String filename, String tagName, String key, int failurePriority )

         throws MojoFailureException, MojoExecutionException

     {

         if ( aggregate && !project.isExecutionRoot() )

         {

             return;

         }

         if ( "java".equals( language ) || aggregate )

         {

             File outputFile = new File( targetDirectory, filename );

             if ( outputFile.exists() )

             {

                 try

                 {

                     XmlPullParser xpp = new MXParser();

                     FileReader freader = new FileReader( outputFile );

                     BufferedReader breader = new BufferedReader( freader );

                     xpp.setInput( breader );

                     Map violations = getViolations( xpp, tagName, failurePriority );

                     List failures = (List) violations.get( FAILURES_KEY );

                     List warnings = (List) violations.get( WARNINGS_KEY );

                     if ( verbose )

                     {

                         printErrors( failures, warnings );

                     }

                     int failureCount = failures.size();

                     int warningCount = warnings.size();

                     String message = getMessage( failureCount, warningCount, key, outputFile );

                     if ( failureCount > 0 && failOnViolation )

                     {

                         throw new MojoFailureException( message );

                     }

                     this.getLog().info( message );

                 }

                 catch ( IOException e )

                 {

                     throw new MojoExecutionException(

                                                       "Unable to read PMD results xml: " + outputFile.getAbsolutePath(),

                                                       e );

                 }

                 catch ( XmlPullParserException e )

                 {

                     throw new MojoExecutionException(

                                                       "Unable to read PMD results xml: " + outputFile.getAbsolutePath(),

                                                       e );

                 }

             }

             else

             {

                 throw new MojoFailureException( "Unable to perform check, " + "unable to find " + outputFile );

             }

         }

     }

     /**

      * Method for collecting the violations found by the PMD tool

      * 

      * @param xpp

      *            the xml parser object

      * @param tagName

      *            the element that will be checked

      * @return an int that specifies the number of violations found

      * @throws XmlPullParserException

      * @throws IOException

      */

     private Map getViolations( XmlPullParser xpp, String tagName, int failurePriority )

         throws XmlPullParserException, IOException

     {

         int eventType = xpp.getEventType();

         List failures = new ArrayList();

         List warnings = new ArrayList();

         while ( eventType != XmlPullParser.END_DOCUMENT )

         {

             if ( eventType == XmlPullParser.START_TAG && tagName.equals( xpp.getName() ) )

             {

                 Map details = getErrorDetails( xpp );

                 try

                 {

                     int priority = Integer.parseInt( (String) details.get( "priority" ) );

                     if ( priority <= failurePriority )

                     {

                         failures.add( details );

                     }

                     else

                     {

                         warnings.add( details );

                     }

                 }

                 catch ( NumberFormatException e )

                 {

                     // i don't know what priority this is. Treat it like a

                     // failure

                     failures.add( details );

                 }

                 catch ( NullPointerException e )

                 {

                     // i don't know what priority this is. Treat it like a

                     // failure

                     failures.add( details );

                 }

             }

             eventType = xpp.next();

         }

         HashMap map = new HashMap( 2 );

         map.put( FAILURES_KEY, failures );

         map.put( WARNINGS_KEY, warnings );

         return map;

     }

     /**

      * Prints the warnings and failures

      * 

      * @param failures

      *            list of failures

      * @param warnings

      *            list of warnings

      */

     protected void printErrors( List failures, List warnings )

     {

         Iterator iter = warnings.iterator();

         while ( iter.hasNext() )

         {

             printError( (Map) iter.next(), "Warning" );

         }

         iter = failures.iterator();

         while ( iter.hasNext() )

         {

             printError( (Map) iter.next(), "Failure" );

         }

     }

     /**

      * Gets the output message

      * 

      * @param failureCount

      * @param warningCount

      * @param key

      * @param outputFile

      * @return

      */

     private String getMessage( int failureCount, int warningCount, String key, File outputFile )

     {

         StringBuffer message = new StringBuffer();

         if ( failureCount > 0 || warningCount > 0 )

         {

             if ( failureCount > 0 )

             {

                 message.append( "You have " + failureCount + " " + key + ( failureCount > 1 ? "s" : "" ) );

             }

             if ( warningCount > 0 )

             {

                 if ( failureCount > 0 )

                 {

                     message.append( " and " );

                 }

                 else

                 {

                     message.append( "You have " );

                 }

                 message.append( warningCount + " warning" + ( warningCount > 1 ? "s" : "" ) );

             }

             message.append( ". For more details see:" + outputFile.getAbsolutePath() );

         }

         return message.toString();

     }

     /**

      * Formats the failure details and prints them as an INFO message

      * 

      * @param item

      */

     protected abstract void printError( Map item, String severity );

     /**

      * Gets the attributes and text for the violation tag and puts them in a

      * HashMap

      * 

      * @param xpp

      * @throws XmlPullParserException

      * @throws IOException

      */

     protected abstract Map getErrorDetails( XmlPullParser xpp )

         throws XmlPullParserException, IOException;

 }