/*
    * 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.
   */
  package org.apache.maven.reporting;
  
  import java.io.File;
  import java.io.FileOutputStream;
  import java.io.IOException;
  import java.io.OutputStreamWriter;
  import java.io.Writer;
  import java.util.Date;
  import java.util.HashMap;
  import java.util.List;
  import java.util.Locale;
  import java.util.Map;
  
  import org.apache.maven.archiver.MavenArchiver;
  import org.apache.maven.artifact.Artifact;
  import org.apache.maven.doxia.sink.Sink;
  import org.apache.maven.doxia.sink.SinkFactory;
  import org.apache.maven.doxia.site.SiteModel;
  import org.apache.maven.doxia.siterenderer.DocumentRenderingContext;
  import org.apache.maven.doxia.siterenderer.Renderer;
  import org.apache.maven.doxia.siterenderer.RendererException;
  import org.apache.maven.doxia.siterenderer.SiteRenderingContext;
  import org.apache.maven.doxia.siterenderer.sink.SiteRendererSink;
  import org.apache.maven.doxia.tools.SiteTool;
  import org.apache.maven.doxia.tools.SiteToolException;
  import org.apache.maven.plugin.AbstractMojo;
  import org.apache.maven.plugin.MojoExecution;
  import org.apache.maven.plugin.MojoExecutionException;
  import org.apache.maven.plugins.annotations.Component;
  import org.apache.maven.plugins.annotations.Parameter;
  import org.apache.maven.project.MavenProject;
  import org.apache.maven.shared.utils.WriterFactory;
  import org.codehaus.plexus.PlexusContainer;
  import org.codehaus.plexus.component.repository.exception.ComponentLookupException;
  import org.codehaus.plexus.util.ReaderFactory;
  import org.eclipse.aether.RepositorySystemSession;
  import org.eclipse.aether.repository.RemoteRepository;
  
  import static org.apache.maven.shared.utils.logging.MessageUtils.buffer;
  
  /**
   * The basis for a Maven report which can be generated both as part of a site generation or
   * as a direct standalone goal invocation.
   * Both invocations are delegated to <code>abstract executeReport( Locale )</code> from:
   * <ul>
   * <li>Mojo's <code>execute()</code> method, see maven-plugin-api</li>
   * <li>MavenMultiPageReport's <code>generate( Sink, SinkFactory, Locale )</code>, see maven-reporting-api</li>
   * </ul>
   *
   * @author <a href="evenisse@apache.org">Emmanuel Venisse</a>
   * @since 2.0
   * @see #execute() <code>Mojo.execute()</code>, from maven-plugin-api
   * @see #generate(Sink, SinkFactory, Locale) <code>MavenMultiPageReport.generate( Sink, SinkFactory, Locale )</code>,
   *  from maven-reporting-api
   * @see #executeReport(Locale) <code>abstract executeReport( Locale )</code>
   */
  public abstract class AbstractMavenReport extends AbstractMojo implements MavenMultiPageReport {
      /**
       * The output directory for the report. Note that this parameter is only evaluated if the goal is run directly from
       * the command line. If the goal is run indirectly as part of a site generation, the output directory configured in
       * the Maven Site Plugin is used instead.
       */
      @Parameter(defaultValue = "${project.reporting.outputDirectory}", readonly = true, required = true)
      protected File outputDirectory;
  
      /**
       * The Maven Project.
       */
      @Parameter(defaultValue = "${project}", readonly = true, required = true)
      protected MavenProject project;
  
      /**
       * The mojo execution
       */
      @Parameter(defaultValue = "${mojoExecution}", readonly = true, required = true)
      protected MojoExecution mojoExecution;
  
      /**
       * The reactor projects.
       */
      @Parameter(defaultValue = "${reactorProjects}", required = true, readonly = true)
     protected List<MavenProject> reactorProjects;
 
     /**
      * Specifies the input encoding.
      */
     @Parameter(property = "encoding", defaultValue = "${project.build.sourceEncoding}", readonly = true)
     private String inputEncoding;
 
     /**
      * Specifies the output encoding.
      */
     @Parameter(property = "outputEncoding", defaultValue = "${project.reporting.outputEncoding}", readonly = true)
     private String outputEncoding;
 
     /**
      * The repository system session.
      */
     @Parameter(defaultValue = "${repositorySystemSession}", readonly = true, required = true)
     protected RepositorySystemSession repoSession;
 
     /**
      * Remote project repositories used for the project.
      */
     @Parameter(defaultValue = "${project.remoteProjectRepositories}", readonly = true, required = true)
     protected List<RemoteRepository> remoteProjectRepositories;
 
     /**
      * Directory containing the <code>site.xml</code> file.
      */
     @Parameter(defaultValue = "${basedir}/src/site")
     protected File siteDirectory;
 
     /**
      * The locale to use  when the report generation is invoked directly as a standalone Mojo.
      * <p>
      * <b>Default value is</b>: {@link SiteTool#DEFAULT_LOCALE}
      *
      * @see SiteTool#getSiteLocales(String)
      */
     @Parameter(defaultValue = "default")
     protected String locale;
 
     /**
      * SiteTool.
      */
     @Component
     protected SiteTool siteTool;
 
     /**
      * Doxia Site Renderer component.
      */
     @Component
     protected Renderer siteRenderer;
 
     /** The current sink to use */
     private Sink sink;
 
     /** The sink factory to use */
     private SinkFactory sinkFactory;
 
     /** The current report output directory to use */
     private File reportOutputDirectory;
 
     /**
      * The report output format: null by default, to represent a site, but can be configured to a Doxia Sink id.
      */
     @Parameter(property = "output.format")
     protected String outputFormat;
 
     @Component
     private PlexusContainer container;
 
     /**
      * This method is called when the report generation is invoked directly as a standalone Mojo.
      *
      * @throws MojoExecutionException if an error occurs when generating the report
      * @see org.apache.maven.plugin.Mojo#execute()
      */
     @Override
     public void execute() throws MojoExecutionException {
         if (!canGenerateReport()) {
             return;
         }
 
         if (outputFormat != null) {
             reportToMarkup();
         } else {
             reportToSite();
         }
     }
 
     private void reportToMarkup() throws MojoExecutionException {
         getLog().info("Rendering to " + outputFormat + " markup");
 
         if (!isExternalReport()) {
             String filename = getOutputName() + '.' + outputFormat;
             try {
                 sinkFactory = container.lookup(SinkFactory.class, outputFormat);
                 sink = sinkFactory.createSink(outputDirectory, filename);
             } catch (ComponentLookupException cle) {
                 throw new MojoExecutionException(
                         "Cannot find SinkFactory for Doxia output format: " + outputFormat, cle);
             } catch (IOException ioe) {
                 throw new MojoExecutionException("Cannot create sink to " + new File(outputDirectory, filename), ioe);
             }
         }
 
         try {
             Locale locale = getLocale();
             generate(sink, sinkFactory, locale);
         } catch (MavenReportException e) {
             throw new MojoExecutionException(
                     "An error has occurred in " + getName(Locale.ENGLISH) + " report generation.", e);
         } finally {
             if (sink != null) {
                 sink.close();
             }
         }
     }
 
     private void reportToSite() throws MojoExecutionException {
         File outputDirectory = new File(getOutputDirectory());
 
         String filename = getOutputName() + ".html";
 
         Locale locale = getLocale();
 
         try {
             SiteRenderingContext siteContext = createSiteRenderingContext(locale);
 
             // copy resources
             getSiteRenderer().copyResources(siteContext, outputDirectory);
 
             String reportMojoInfo = mojoExecution.getPlugin().getId() + ":" + mojoExecution.getGoal();
             DocumentRenderingContext docRenderingContext =
                     new DocumentRenderingContext(outputDirectory, getOutputName(), reportMojoInfo);
 
             SiteRendererSink sink = new SiteRendererSink(docRenderingContext);
 
             // TODO Compared to Maven Site Plugin multipage reports will not work and fail with a NPE
             generate(sink, null, locale);
 
             if (!isExternalReport()) // MSHARED-204: only render Doxia sink if not an external report
             {
                 outputDirectory.mkdirs();
 
                 try (Writer writer = new OutputStreamWriter(
                         new FileOutputStream(new File(outputDirectory, filename)), getOutputEncoding())) {
                     // render report
                     getSiteRenderer().mergeDocumentIntoSite(writer, sink, siteContext);
                 }
             }
 
             // copy generated resources also
             getSiteRenderer().copyResources(siteContext, outputDirectory);
         } catch (RendererException | IOException | MavenReportException | SiteToolException e) {
             throw new MojoExecutionException(
                     "An error has occurred in " + getName(Locale.ENGLISH) + " report generation.", e);
         }
     }
 
     private SiteRenderingContext createSiteRenderingContext(Locale locale)
             throws MavenReportException, IOException, SiteToolException {
         SiteModel siteModel = siteTool.getSiteModel(
                 siteDirectory, locale, project, reactorProjects, repoSession, remoteProjectRepositories);
 
         Map<String, Object> templateProperties = new HashMap<>();
         // We tell the skin that we are rendering in standalone mode
         templateProperties.put("standalone", Boolean.TRUE);
         templateProperties.put("project", getProject());
         templateProperties.put("inputEncoding", getInputEncoding());
         templateProperties.put("outputEncoding", getOutputEncoding());
         // Put any of the properties in directly into the Velocity context
         for (Map.Entry<Object, Object> entry : getProject().getProperties().entrySet()) {
             templateProperties.put((String) entry.getKey(), entry.getValue());
         }
 
         SiteRenderingContext context;
         try {
             Artifact skinArtifact =
                     siteTool.getSkinArtifactFromRepository(repoSession, remoteProjectRepositories, siteModel.getSkin());
 
             getLog().info(buffer().a("Rendering content with ")
                     .strong(skinArtifact.getId() + " skin")
                     .toString());
 
             context = siteRenderer.createContextForSkin(
                     skinArtifact, templateProperties, siteModel, project.getName(), locale);
         } catch (SiteToolException e) {
             throw new MavenReportException("Failed to retrieve skin artifact", e);
         } catch (RendererException e) {
             throw new MavenReportException("Failed to create context for skin", e);
         }
 
         // Add publish date
         String outputTimestamp = getProject().getProperties().getProperty("project.build.outputTimestamp");
         MavenArchiver.parseBuildOutputTimestamp(outputTimestamp).ifPresent(v -> {
             context.setPublishDate(Date.from(v));
         });
 
         // Generate static site
         context.setRootDirectory(project.getBasedir());
 
         return context;
     }
 
     /**
      * Generate a report.
      *
      * @param sink the sink to use for the generation.
      * @param locale the wanted locale to generate the report, could be null.
      * @throws MavenReportException if any
      * @deprecated use {@link #generate(Sink, SinkFactory, Locale)} instead.
      */
     @Deprecated
     @Override
     public void generate(Sink sink, Locale locale) throws MavenReportException {
         generate(sink, null, locale);
     }
 
     /**
      * This method is called when the report generation is invoked by maven-site-plugin.
      *
      * @param sink
      * @param sinkFactory
      * @param locale
      * @throws MavenReportException
      */
     @Override
     public void generate(Sink sink, SinkFactory sinkFactory, Locale locale) throws MavenReportException {
         if (!canGenerateReport()) {
             getLog().info("This report cannot be generated as part of the current build. "
                     + "The report name should be referenced in this line of output.");
             return;
         }
 
         this.sink = sink;
 
         this.sinkFactory = sinkFactory;
 
         executeReport(locale);
 
         closeReport();
     }
 
     /**
      * @return CATEGORY_PROJECT_REPORTS
      */
     @Override
     public String getCategoryName() {
         return CATEGORY_PROJECT_REPORTS;
     }
 
     @Override
     public File getReportOutputDirectory() {
         if (reportOutputDirectory == null) {
             reportOutputDirectory = new File(getOutputDirectory());
         }
 
         return reportOutputDirectory;
     }
 
     @Override
     public void setReportOutputDirectory(File reportOutputDirectory) {
         this.reportOutputDirectory = reportOutputDirectory;
         this.outputDirectory = reportOutputDirectory;
     }
 
     protected String getOutputDirectory() {
         return outputDirectory.getAbsolutePath();
     }
 
     protected MavenProject getProject() {
         return project;
     }
 
     protected Renderer getSiteRenderer() {
         return siteRenderer;
     }
 
     /**
      * Gets the input files encoding.
      *
      * @return The input files encoding, never <code>null</code>.
      */
     protected String getInputEncoding() {
         return (inputEncoding == null) ? ReaderFactory.FILE_ENCODING : inputEncoding;
     }
 
     /**
      * Gets the effective reporting output files encoding.
      *
      * @return The effective reporting output file encoding, never <code>null</code>.
      */
     protected String getOutputEncoding() {
         return (outputEncoding == null) ? WriterFactory.UTF_8 : outputEncoding;
     }
 
     /**
      * Gets the locale
      *
      * @return the locale for this standalone report
      */
     protected Locale getLocale() {
         return siteTool.getSiteLocales(locale).get(0);
     }
 
     /**
      * Actions when closing the report.
      */
     protected void closeReport() {
         if (getSink() != null) {
             getSink().close();
         }
     }
 
     /**
      * @return the sink used
      */
     public Sink getSink() {
         return sink;
     }
 
     /**
      * @return the sink factory used
      */
     public SinkFactory getSinkFactory() {
         return sinkFactory;
     }
 
     /**
      * @see org.apache.maven.reporting.MavenReport#isExternalReport()
      * @return {@code false} by default.
      */
     @Override
     public boolean isExternalReport() {
         return false;
     }
 
     @Override
     public boolean canGenerateReport() {
         return true;
     }
 
     /**
      * Execute the generation of the report.
      *
      * @param locale the wanted locale to return the report's description, could be <code>null</code>.
      * @throws MavenReportException if any
      */
     protected abstract void executeReport(Locale locale) throws MavenReportException;
 }