package org.apache.maven.plugins.enforcer;
   
   /*
    * 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.util.ArrayList;
  import java.util.Hashtable;
  import java.util.List;
  
  import org.apache.maven.enforcer.rule.api.EnforcerRule;
  import org.apache.maven.enforcer.rule.api.EnforcerRuleException;
  import org.apache.maven.enforcer.rule.api.EnforcerRuleHelper;
  import org.apache.maven.execution.MavenSession;
  import org.apache.maven.plugin.AbstractMojo;
  import org.apache.maven.plugin.MojoExecution;
  import org.apache.maven.plugin.MojoExecutionException;
  import org.apache.maven.plugin.logging.Log;
  import org.apache.maven.plugins.annotations.Component;
  import org.apache.maven.plugins.annotations.Parameter;
  import org.apache.maven.project.MavenProject;
  import org.apache.maven.project.path.PathTranslator;
  import org.codehaus.plexus.PlexusConstants;
  import org.codehaus.plexus.PlexusContainer;
  import org.codehaus.plexus.context.Context;
  import org.codehaus.plexus.context.ContextException;
  import org.codehaus.plexus.personality.plexus.lifecycle.phase.Contextualizable;
  
  /**
   * @author <a href="mailto:brianf@apache.org">Brian Fox</a>
   */
  public abstract class AbstractEnforceMojo
      extends AbstractMojo
      implements Contextualizable
  {
      /**
       * This is a static variable used to persist the cached results across plugin invocations.
       */
      protected static Hashtable<String, EnforcerRule> cache = new Hashtable<String, EnforcerRule>();
  
      /**
       * Path Translator needed by the ExpressionEvaluator
       */
      @Component( role = PathTranslator.class )
      protected PathTranslator translator;
      
      /**
       * MojoExecution needed by the ExpressionEvaluator
       */
      @Parameter( defaultValue = "${mojoExecution}", readonly = true, required = true )
      protected MojoExecution mojoExecution;
  
      /**
       * The MavenSession
       */
      @Parameter( defaultValue = "${session}", readonly = true, required = true )
      protected MavenSession session;
  
      /**
       * POM
       */
      @Parameter( defaultValue = "${project}", readonly = true, required = true )
      protected MavenProject project;
  
      /**
       * Flag to easily skip all checks
       */
      @Parameter( property = "enforcer.skip", defaultValue = "false" )
      protected boolean skip = false;
  
      /**
       * Use this flag to disable rule result caching. This will cause all rules to execute on each project even if the
       * rule indicates it can safely be cached.
       */
      @Parameter( property = "enforcer.ignoreCache", defaultValue = "false" )
      protected boolean ignoreCache = false;
  
      // set by the contextualize method. Only way to get the
      // plugin's container in 2.0.x
      protected PlexusContainer container;
  
      public void contextualize( Context context )
          throws ContextException
      {
         container = (PlexusContainer) context.get( PlexusConstants.PLEXUS_KEY );
     }
 
     /**
      * Entry point to the mojo
      * 
      * @throws MojoExecutionException
      */
     public void execute()
         throws MojoExecutionException
     {
         Log log = this.getLog();
         EnforcerExpressionEvaluator evaluator = new EnforcerExpressionEvaluator( session, translator, project,
                                                                                  mojoExecution );
         // the entire execution can be easily skipped
         if ( !skip )
         {
             // list to store exceptions
             List<String> list = new ArrayList<String>();
             // make sure the rules exist
             if ( getRules() != null && getRules().length > 0 )
             {
                 String currentRule = "Unknown";
                 // create my helper
                 EnforcerRuleHelper helper = new DefaultEnforcementRuleHelper( session, evaluator, log, container );
                 // if we are only warning, then disable
                 // failFast
                 if ( !isFail() )
                 {
                     setFailFast( false );
                 }
                 // go through each rule
                 for ( int i = 0; i < getRules().length; i++ )
                 {
                     // prevent against empty rules
                     EnforcerRule rule = getRules()[i];
                     if ( rule != null )
                     {
                         // store the current rule for
                         // logging purposes
                         currentRule = rule.getClass().getName();
                         log.debug( "Executing rule: " + currentRule );
                         try
                         {
                             if ( ignoreCache || shouldExecute( rule ) )
                             {
                                 // execute the rule
                                 // noinspection SynchronizationOnLocalVariableOrMethodParameter
                                 synchronized ( rule )
                                 {
                                     rule.execute( helper );
                                 }
                             }
                         }
                         catch ( EnforcerRuleException e )
                         {
                             // i can throw an exception
                             // because failfast will be
                             // false if fail is false.
                             if ( isFailFast() )
                             {
                                 throw new MojoExecutionException( currentRule + " failed with message:\n"
                                     + e.getMessage(), e );
                             }
                             else
                             {
                                 list.add( createRuleMessage( i, currentRule, e ) );
                                 log.debug( "Adding failure due to exception", e );
                             }
                         }
                     }
                 }
                 // if we found anything
                 if ( !list.isEmpty() )
                 {
                     for ( String failure : list )
                     {
                         log.warn( failure );
                     }
                     if ( isFail() )
                     {
                         // CHECKSTYLE_OFF: LineLength
                         throw new MojoExecutionException(
                                                           "Some Enforcer rules have failed. Look above for specific messages explaining why the rule failed." );
                         // CHECKSTYLE_ON: LineLength
                     }
                 }
             }
             else
             {
                 // CHECKSTYLE_OFF: LineLength
                 throw new MojoExecutionException(
                                                   "No rules are configured. Use the skip flag if you want to disable execution." );
                 // CHECKSTYLE_ON: LineLength
             }
         }
         else
         {
             log.info( "Skipping Rule Enforcement." );
         }
     }
 
     /**
      * This method determines if a rule should execute based on the cache
      *
      * @param rule the rule to verify
      * @return {@code true} if rule should be executed, otherwise {@code false}
      */
     protected boolean shouldExecute( EnforcerRule rule )
     {
         if ( rule.isCacheable() )
         {
             Log log = this.getLog();
             log.debug( "Rule " + rule.getClass().getName() + " is cacheable." );
             String key = rule.getClass().getName() + " " + rule.getCacheId();
             if ( EnforceMojo.cache.containsKey( key ) )
             {
                 log.debug( "Key " + key + " was found in the cache" );
                 if ( rule.isResultValid( (EnforcerRule) cache.get( key ) ) )
                 {
                     log.debug( "The cached results are still valid. Skipping the rule: " + rule.getClass().getName() );
                     return false;
                 }
             }
             // add it to the cache of executed rules
             EnforceMojo.cache.put( key, rule );
         }
         return true;
     }
 
     /**
      * @return the fail
      */
     public abstract boolean isFail();
 
     /**
      * @return the rules
      */
     public abstract EnforcerRule[] getRules();
 
     /**
      * @param theRules to set.
      */
     public abstract void setRules( EnforcerRule[] theRules );
 
     /**
      * @return the skip
      */
     public boolean isSkip()
     {
         return this.skip;
     }
 
     /**
      * @param theSkip the skip to set
      */
     public void setSkip( boolean theSkip )
     {
         this.skip = theSkip;
     }
 
     /**
      * @return the failFast
      */
     public abstract boolean isFailFast();
 
     /**
      * @param failFast to set
      */
     public abstract void setFailFast( boolean failFast );
 
     /**
      * @return the project
      */
     public MavenProject getProject()
     {
         return this.project;
     }
 
     /**
      * @param theProject the project to set
      */
     public void setProject( MavenProject theProject )
     {
         this.project = theProject;
     }
 
     /**
      * @return the session
      */
     public MavenSession getSession()
     {
         return this.session;
     }
 
     /**
      * @param theSession the session to set
      */
     public void setSession( MavenSession theSession )
     {
         this.session = theSession;
     }
 
     /**
      * @return the translator
      */
     public PathTranslator getTranslator()
     {
         return this.translator;
     }
 
     /**
      * @param theTranslator the translator to set
      */
     public void setTranslator( PathTranslator theTranslator )
     {
         this.translator = theTranslator;
     }
 
     /**
      * Returns the error message displayed when failFast is set to false.
      *
      * @param i index
      * @param currentRule name of the current rule.
      * @param e rule exception
      * @return rule message
      */
     protected abstract String createRuleMessage( int i, String currentRule, EnforcerRuleException e );
 }