package org.apache.maven.plugin.docck;
   
   /*
    * 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 org.apache.hc.client5.http.auth.AuthScope;
  import org.apache.hc.client5.http.auth.UsernamePasswordCredentials;
  import org.apache.hc.client5.http.classic.methods.HttpHead;
  import org.apache.hc.client5.http.config.RequestConfig;
  import org.apache.hc.client5.http.cookie.StandardCookieSpec;
  import org.apache.hc.client5.http.impl.auth.BasicCredentialsProvider;
  import org.apache.hc.client5.http.impl.classic.CloseableHttpClient;
  import org.apache.hc.client5.http.impl.classic.CloseableHttpResponse;
  import org.apache.hc.client5.http.impl.classic.HttpClientBuilder;
  import org.apache.hc.client5.http.impl.classic.HttpClients;
  import org.apache.hc.core5.http.HttpHeaders;
  import org.apache.hc.core5.http.HttpHost;
  import org.apache.hc.core5.http.message.BasicHeader;
  import org.apache.hc.core5.util.Timeout;
  import org.apache.maven.model.IssueManagement;
  import org.apache.maven.model.License;
  import org.apache.maven.model.Organization;
  import org.apache.maven.model.Prerequisites;
  import org.apache.maven.model.Scm;
  import org.apache.maven.plugin.AbstractMojo;
  import org.apache.maven.plugin.MojoExecutionException;
  import org.apache.maven.plugin.MojoFailureException;
  import org.apache.maven.plugin.docck.reports.DocumentationReport;
  import org.apache.maven.plugin.docck.reports.DocumentationReporter;
  import org.apache.maven.plugins.annotations.Parameter;
  import org.apache.maven.project.MavenProject;
  import org.apache.maven.settings.Proxy;
  import org.apache.maven.settings.Settings;
  import org.apache.maven.shared.model.fileset.FileSet;
  import org.apache.maven.shared.model.fileset.util.FileSetManager;
  import org.codehaus.plexus.util.StringUtils;
  
  import java.io.File;
  import java.io.FileWriter;
  import java.io.IOException;
  import java.net.MalformedURLException;
  import java.net.URL;
  import java.util.ArrayList;
  import java.util.LinkedHashMap;
  import java.util.List;
  import java.util.Map;
  
  import static java.util.Collections.singletonList;
  
  /**
   * Performs the heavy lifting for documentation checks. This is designed to be
   * reused for other types of projects, too.
   *
   * @author jdcasey
   */
  public abstract class AbstractCheckDocumentationMojo
      extends AbstractMojo
  {
      private static final int HTTP_STATUS_200 = 200;
  
      /**
       */
      @Parameter( property = "reactorProjects", readonly = true, required = true )
      private List<MavenProject> reactorProjects;
  
      /**
       * An optional location where the results will be written to. If this is
       * not specified the results will be written to the console.
       */
      @Parameter( property = "output" )
      private File output;
  
      /**
       * Directory where the site source for the project is located.
       */
      @Parameter( property = "siteDirectory", defaultValue = "src/site" )
      protected String siteDirectory;
  
      /**
       * Sets whether this plugin is running in offline or online mode. Also
       * useful when you don't want to verify http URLs.
       */
      @Parameter( property = "settings.offline" )
     private boolean offline;
 
     /**
      * The current user system settings for use in Maven.
      */
     @Parameter( defaultValue = "${settings}", readonly = true, required = true )
     private Settings settings;
 
     private CloseableHttpClient httpClient;
 
     private FileSetManager fileSetManager = new FileSetManager();
 
     private List<String> validUrls = new ArrayList<>();
 
     protected List<MavenProject> getReactorProjects()
     {
         return reactorProjects;
     }
 
     @Override
     public void execute()
         throws MojoExecutionException, MojoFailureException
     {
 
         String httpUserAgent = "maven-docck-plugin/1.x" + " (Java " + System.getProperty( "java.version" ) + "; "
                 + System.getProperty( "os.name" ) + " " + System.getProperty( "os.version" ) + ")";
         HttpClientBuilder httpClientBuilder = HttpClients.custom()
               .setDefaultRequestConfig( RequestConfig.custom()
                       .setConnectTimeout( Timeout.ofSeconds( 5 ) )
                       .setResponseTimeout( Timeout.ofSeconds( 5 ) )
                       .setCookieSpec( StandardCookieSpec.STRICT )
                       .build() )
               .setDefaultHeaders( singletonList( new BasicHeader( HttpHeaders.USER_AGENT, httpUserAgent ) ) );
 
         setupProxy( httpClientBuilder );
 
         httpClient = httpClientBuilder.build();
 
         if ( output != null )
         {
             getLog().info( "Writing documentation check results to: " + output );
         }
 
         Map<MavenProject, DocumentationReporter> reporters = new LinkedHashMap<>();
         boolean hasErrors = false;
 
         for ( MavenProject project : reactorProjects )
         {
             if ( approveProjectPackaging( project.getPackaging() ) )
             {
                 getLog().info( "Checking project: " + project.getName() );
 
                 DocumentationReporter reporter = new DocumentationReporter();
 
                 checkProject( project, reporter );
 
                 if ( !hasErrors && reporter.hasErrors() )
                 {
                     hasErrors = true;
                 }
 
                 reporters.put( project, reporter );
             }
             else
             {
                 getLog().info( "Skipping unsupported project: " + project.getName() );
             }
         }
 
         String messages;
 
         messages = buildErrorMessages( reporters );
 
         if ( !hasErrors )
         {
             messages += "No documentation errors were found.";
         }
 
         try
         {
             writeMessages( messages, hasErrors );
         }
         catch ( IOException e )
         {
             throw new MojoExecutionException( "Error writing results to output file: " + output );
         }
 
         if ( hasErrors )
         {
             String logLocation;
             if ( output == null )
             {
                 logLocation = "Please see the console output above for more information.";
             }
             else
             {
                 logLocation = "Please see \'" + output + "\' for more information.";
             }
 
             throw new MojoFailureException( "Documentation problems were found. " + logLocation );
         }
     }
 
     /**
      * Setup proxy access if needed.
      * @param httpClientBuilder 
      */
     private void setupProxy( HttpClientBuilder httpClientBuilder )
     {
         Proxy settingsProxy = settings.getActiveProxy();
 
         if ( settingsProxy != null )
         {
             String proxyUsername = settingsProxy.getUsername();
 
             String proxyPassword = settingsProxy.getPassword();
 
             String proxyHost = settingsProxy.getHost();
 
             int proxyPort = settingsProxy.getPort();
 
             if ( proxyHost != null && !proxyHost.isEmpty() )
             {
                 httpClientBuilder.setProxy( new HttpHost( proxyHost, proxyPort ) );
 
                 getLog().info( "Using proxy [" + proxyHost + "] at port [" + proxyPort + "]." );
 
                 if ( proxyUsername != null && !proxyUsername.isEmpty() )
                 {
                     getLog().info( "Using proxy user [" + proxyUsername + "]." );
 
                     BasicCredentialsProvider credsProvider = new BasicCredentialsProvider();
                     credsProvider.setCredentials(
                             new AuthScope( proxyHost, proxyPort ),
                             new UsernamePasswordCredentials( proxyUsername, proxyPassword.toCharArray() ) );
 
                     httpClientBuilder.setDefaultCredentialsProvider( credsProvider );
                 }
             }
         }
     }
 
     private String buildErrorMessages( Map<MavenProject, DocumentationReporter> reporters )
     {
         String messages = "";
         StringBuilder buffer = new StringBuilder();
 
         for ( Map.Entry<MavenProject, DocumentationReporter> entry : reporters.entrySet() )
         {
             MavenProject project = entry.getKey();
             DocumentationReporter reporter = entry.getValue();
 
             if ( !reporter.getMessages().isEmpty() )
             {
                 buffer.append( System.lineSeparator() ).append( "o " ).append( project.getName() );
                 buffer.append( " (" );
                 final int numberOfErrors = reporter.getMessagesByType( DocumentationReport.TYPE_ERROR ).size();
                 buffer.append( numberOfErrors ).append( " error" ).append( numberOfErrors == 1 ? "" : "s" );
                 buffer.append( ", " );
                 final int numberOfWarnings = reporter.getMessagesByType( DocumentationReport.TYPE_WARN ).size();
                 buffer.append( numberOfWarnings ).append( " warning" ).append( numberOfWarnings == 1 ? "" : "s" );
                 buffer.append( ")" );
                 buffer.append( System.lineSeparator() );
 
                 for ( String error : reporter.getMessages() )
                 {
                     buffer.append( "  " ).append( error ).append( System.lineSeparator() );
                 }
             }
         }
 
         if ( buffer.length() > 0 )
         {
             messages = "The following documentation problems were found:" + System.lineSeparator() + buffer.toString();
         }
 
         return messages;
     }
 
     protected abstract boolean approveProjectPackaging( String packaging );
 
     /**
      * Writes the text in messages either to a file or to the console.
      *
      * @param messages The message text
      * @param hasErrors If there were any documentation errors
      * @throws IOException
      */
     private void writeMessages( String messages, boolean hasErrors )
         throws IOException
     {
         if ( output != null )
         {
             try ( FileWriter writer = new FileWriter( output ) )
             {
                 writer.write( messages );
             }
         }
         else
         {
             if ( hasErrors )
             {
                 getLog().error( messages );
             }
             else
             {
                 getLog().info( messages );
             }
         }
     }
 
     private void checkProject( MavenProject project, DocumentationReporter reporter )
     {
         checkPomRequirements( project, reporter );
 
         checkPackagingSpecificDocumentation( project, reporter );
     }
 
     private void checkPomRequirements( MavenProject project, DocumentationReporter reporter )
     {
         checkProjectLicenses( project, reporter );
 
         if ( StringUtils.isEmpty( project.getName() ) )
         {
             reporter.error( "pom.xml is missing the <name> tag." );
         }
 
         if ( StringUtils.isEmpty( project.getDescription() ) )
         {
             reporter.error( "pom.xml is missing the <description> tag." );
         }
 
         if ( StringUtils.isEmpty( project.getUrl() ) )
         {
             reporter.error( "pom.xml is missing the <url> tag." );
         }
         else
         {
             checkURL( project.getUrl(), "project site", reporter );
         }
 
         if ( project.getIssueManagement() == null )
         {
             reporter.error( "pom.xml is missing the <issueManagement> tag." );
         }
         else
         {
             IssueManagement issueMngt = project.getIssueManagement();
             if ( StringUtils.isEmpty( issueMngt.getUrl() ) )
             {
                 reporter.error( "pom.xml is missing the <url> tag in <issueManagement>." );
             }
             else
             {
                 checkURL( issueMngt.getUrl(), "Issue Management", reporter );
             }
         }
 
         if ( project.getPrerequisites() == null )
         {
             reporter.error( "pom.xml is missing the <prerequisites> tag." );
         }
         else
         {
             Prerequisites prereq = project.getPrerequisites();
             if ( StringUtils.isEmpty( prereq.getMaven() ) )
             {
                 reporter.error( "pom.xml is missing the <prerequisites>/<maven> tag." );
             }
         }
 
         if ( StringUtils.isEmpty( project.getInceptionYear() ) )
         {
             reporter.error( "pom.xml is missing the <inceptionYear> tag." );
         }
 
         if ( project.getMailingLists().size() == 0 )
         {
             reporter.warn( "pom.xml has no <mailingLists>/<mailingList> specified." );
         }
 
         if ( project.getScm() == null )
         {
             reporter.warn( "pom.xml is missing the <scm> tag." );
         }
         else
         {
             Scm scm = project.getScm();
             if ( StringUtils.isEmpty( scm.getConnection() ) && StringUtils.isEmpty( scm.getDeveloperConnection() )
                 && StringUtils.isEmpty( scm.getUrl() ) )
             {
                 reporter.warn( "pom.xml is missing the child tags under the <scm> tag." );
             }
             else if ( scm.getUrl() != null )
             {
                 checkURL( scm.getUrl(), "scm", reporter );
             }
         }
 
         if ( project.getOrganization() == null )
         {
             reporter.error( "pom.xml is missing the <organization> tag." );
         }
         else
         {
             Organization org = project.getOrganization();
             if ( StringUtils.isEmpty( org.getName() ) )
             {
                 reporter.error( "pom.xml is missing the <organization>/<name> tag." );
             }
             else if ( org.getUrl() != null )
             {
                 checkURL( org.getUrl(), org.getName() + " site", reporter );
             }
         }
     }
 
     private void checkProjectLicenses( MavenProject project, DocumentationReporter reporter )
     {
         @SuppressWarnings( "unchecked" )
         List<License> licenses = project.getLicenses();
 
         if ( licenses == null || licenses.isEmpty() )
         {
             reporter.error( "pom.xml has no <licenses>/<license> specified." );
         }
         else
         {
             for ( License license : licenses )
             {
                 if ( StringUtils.isEmpty( license.getName() ) )
                 {
                     reporter.error( "pom.xml is missing the <licenses>/<license>/<name> tag." );
                 }
                 else
                 {
                     String url = license.getUrl();
                     if ( url == null || url.isEmpty() )
                     {
                         reporter.error( "pom.xml is missing the <licenses>/<license>/<url> tag for the license \'"
                             + license.getName() + "\'." );
                     }
                     else
                     {
                         checkURL( url, "license \'" + license.getName() + "\'", reporter );
                     }
                 }
             }
         }
     }
 
     private String getURLProtocol( String url )
         throws MalformedURLException
     {
         URL licenseUrl = new URL( url );
         String protocol = licenseUrl.getProtocol();
 
         if ( protocol != null )
         {
             protocol = protocol.toLowerCase();
         }
 
         return protocol;
     }
 
     private void checkURL( String url, String description, DocumentationReporter reporter )
     {
         try
         {
             String protocol = getURLProtocol( url );
 
             if ( protocol.startsWith( "http" ) )
             {
                 if ( offline )
                 {
                     reporter.warn( "Cannot verify " + description + " in offline mode with URL: \'" + url + "\'." );
                 }
                 else if ( !validUrls.contains( url ) )
                 {
                     HttpHead headMethod = new HttpHead( url );
 
                     try ( CloseableHttpResponse response = httpClient.execute( headMethod ) )
                     {
                         getLog().debug( "Verifying http url: " + url );
                         if ( response.getCode() != HTTP_STATUS_200 )
                         {
                             reporter.error( "Cannot reach " + description + " with URL: \'" + url + "\'." );
                         }
                         else
                         {
                             validUrls.add( url );
                         }
                     }
                     catch ( IOException e )
                     {
                         reporter.error( "Cannot reach " + description + " with URL: \'" + url + "\'.\nError: "
                             + e.getMessage() );
                     }
                 }
             }
             else
             {
                 reporter.warn( "Non-HTTP " + description + " URL not verified." );
             }
         }
         catch ( MalformedURLException e )
         {
             reporter.warn( "The " + description + " appears to have an invalid URL \'" + url + "\'."
                 + " Message: \'" + e.getMessage() + "\'. Trying to access it as a file instead." );
 
             checkFile( url, description, reporter );
         }
     }
 
     private void checkFile( String url, String description, DocumentationReporter reporter )
     {
         File licenseFile = new File( url );
         if ( !licenseFile.exists() )
         {
             reporter.error( "The " + description + " in file \'" + licenseFile.getPath() + "\' does not exist." );
         }
     }
 
     protected abstract void checkPackagingSpecificDocumentation( MavenProject project, DocumentationReporter reporter );
 
     protected boolean findFiles( File siteDirectory, String pattern )
     {
         FileSet fs = new FileSet();
         fs.setDirectory( siteDirectory.getAbsolutePath() );
         fs.setFollowSymlinks( false );
 
         fs.addInclude( "apt/" + pattern + ".apt" );
         fs.addInclude( "apt/" + pattern + ".apt.vm" );
         fs.addInclude( "xdoc/" + pattern + ".xml" );
         fs.addInclude( "xdoc/" + pattern + ".xml.vm" );
         fs.addInclude( "fml/" + pattern + ".fml" );
         fs.addInclude( "fml/" + pattern + ".fml.vm" );
         fs.addInclude( "resources/" + pattern + ".html" );
         fs.addInclude( "resources/" + pattern + ".html.vm" );
 
         String[] includedFiles = fileSetManager.getIncludedFiles( fs );
 
         return includedFiles != null && includedFiles.length > 0;
     }
 }