/*
    * 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.plugins.site.render;
  
  import java.io.File;
  import java.io.FileNotFoundException;
  import java.io.IOException;
  import java.io.OutputStream;
  import java.io.Writer;
  import java.util.ArrayList;
  import java.util.List;
  import java.util.Locale;
  
  import org.apache.maven.doxia.sink.Sink;
  import org.apache.maven.doxia.sink.SinkFactory;
  import org.apache.maven.doxia.siterenderer.DocumentRenderer;
  import org.apache.maven.doxia.siterenderer.Renderer;
  import org.apache.maven.doxia.siterenderer.RendererException;
  import org.apache.maven.doxia.siterenderer.RenderingContext;
  import org.apache.maven.doxia.siterenderer.SiteRenderingContext;
  import org.apache.maven.doxia.siterenderer.sink.SiteRendererSink;
  import org.apache.maven.plugin.logging.Log;
  import org.apache.maven.reporting.MavenMultiPageReport;
  import org.apache.maven.reporting.MavenReport;
  import org.apache.maven.reporting.MavenReportException;
  import org.apache.maven.reporting.exec.MavenReportExecution;
  import org.codehaus.plexus.util.PathTool;
  import org.codehaus.plexus.util.StringUtils;
  import org.codehaus.plexus.util.WriterFactory;
  
  import static org.apache.maven.shared.utils.logging.MessageUtils.buffer;
  
  /**
   * Renders a Maven report in a Doxia site.
   *
   * @author <a href="mailto:brett@apache.org">Brett Porter</a>
   * @see org.apache.maven.doxia.siterenderer.DoxiaDocumentRenderer
   */
  public class ReportDocumentRenderer implements DocumentRenderer {
      private final MavenReport report;
  
      private final RenderingContext renderingContext;
  
      private final String reportMojoInfo;
  
      private final ClassLoader classLoader;
  
      private final Log log;
  
      public ReportDocumentRenderer(
              MavenReportExecution mavenReportExecution, RenderingContext renderingContext, Log log) {
          this.report = mavenReportExecution.getMavenReport();
  
          this.renderingContext = renderingContext;
  
          // full MavenReportExecution prepared by maven-reporting-impl
          this.reportMojoInfo = mavenReportExecution.getPlugin().getArtifactId()
                  + ':'
                  + mavenReportExecution.getPlugin().getVersion()
                  + ':'
                  + mavenReportExecution.getGoal();
  
          this.classLoader = mavenReportExecution.getClassLoader();
  
          this.log = log;
      }
  
      private static class MultiPageSubSink extends SiteRendererSink {
          private File outputDir;
  
          private String outputName;
  
          MultiPageSubSink(File outputDir, String outputName, RenderingContext context) {
              super(context);
              this.outputName = outputName;
              this.outputDir = outputDir;
          }
  
          public String getOutputName() {
              return outputName;
          }
  
          public File getOutputDir() {
             return outputDir;
         }
     }
 
     private static class MultiPageSinkFactory implements SinkFactory {
         /**
          * The report that is (maybe) generating multiple pages
          */
         private MavenReport report;
 
         /**
          * The main RenderingContext, which is the base for the RenderingContext of subpages
          */
         private RenderingContext context;
 
         /**
          * List of sinks (subpages) associated to this report
          */
         private List<MultiPageSubSink> sinks = new ArrayList<MultiPageSubSink>();
 
         MultiPageSinkFactory(MavenReport report, RenderingContext context) {
             this.report = report;
             this.context = context;
         }
 
         @Override
         public Sink createSink(File outputDir, String outputName) {
             // Create a new context, similar to the main one, but with a different output name
             String outputRelativeToTargetSite = PathTool.getRelativeFilePath(
                     report.getReportOutputDirectory().getPath(), new File(outputDir, outputName).getPath());
 
             RenderingContext subSinkContext = new RenderingContext(
                     context.getBasedir(),
                     context.getBasedirRelativePath(),
                     outputRelativeToTargetSite,
                     context.getParserId(),
                     context.getExtension(),
                     context.isEditable(),
                     context.getGenerator());
 
             // Create a sink for this subpage, based on this new context
             MultiPageSubSink sink = new MultiPageSubSink(outputDir, outputName, subSinkContext);
 
             // Add it to the list of sinks associated to this report
             sinks.add(sink);
 
             return sink;
         }
 
         @Override
         public Sink createSink(File arg0, String arg1, String arg2) throws IOException {
             // Not used
             return null;
         }
 
         @Override
         public Sink createSink(OutputStream arg0) throws IOException {
             // Not used
             return null;
         }
 
         @Override
         public Sink createSink(OutputStream arg0, String arg1) throws IOException {
             // Not used
             return null;
         }
 
         public List<MultiPageSubSink> sinks() {
             return sinks;
         }
     }
 
     @Override
     public void renderDocument(Writer writer, Renderer renderer, SiteRenderingContext siteRenderingContext)
             throws RendererException, FileNotFoundException {
         Locale locale = siteRenderingContext.getLocale();
         String localReportName = report.getName(locale);
 
         String msg = "Generating \"" + buffer().strong(localReportName) + "\" report";
         // CHECKSTYLE_OFF: MagicNumber
         log.info(
                 reportMojoInfo == null
                         ? (msg + '.')
                         : (StringUtils.rightPad(msg, 40)
                                 + buffer().strong(" --- ").mojo(reportMojoInfo)));
         // CHECKSTYLE_ON: MagicNumber
 
         // main sink
         SiteRendererSink mainSink = new SiteRendererSink(renderingContext);
         // sink factory, for multi-page reports that need sub-sinks
         MultiPageSinkFactory multiPageSinkFactory = new MultiPageSinkFactory(report, renderingContext);
 
         ClassLoader originalClassLoader = Thread.currentThread().getContextClassLoader();
         try {
             if (classLoader != null) {
                 Thread.currentThread().setContextClassLoader(classLoader);
             }
 
             if (report instanceof MavenMultiPageReport) {
                 // extended multi-page API
                 ((MavenMultiPageReport) report).generate(mainSink, multiPageSinkFactory, locale);
             } else {
                 // old single-page-only API
                 report.generate(mainSink, locale);
             }
         } catch (MavenReportException e) {
             String report = (reportMojoInfo == null) ? ('"' + localReportName + '"') : reportMojoInfo;
             throw new RendererException("Error generating " + report + " report", e);
         } catch (RuntimeException re) {
             // MSITE-836: if report generation throws a RuntimeException, transform to RendererException
             String report = (reportMojoInfo == null) ? ('"' + localReportName + '"') : reportMojoInfo;
             throw new RendererException("Error generating " + report + " report", re);
         } catch (LinkageError e) {
             String report = (reportMojoInfo == null) ? ('"' + localReportName + '"') : reportMojoInfo;
             log.warn(
                     "An issue has occurred with " + report + " report, skipping LinkageError " + e.getMessage()
                             + ", please report an issue to Maven dev team.",
                     e);
         } finally {
             if (classLoader != null) {
                 Thread.currentThread().setContextClassLoader(originalClassLoader);
             }
             mainSink.close();
         }
 
         if (report.isExternalReport()) {
             // external reports are rendered from their own: no Doxia site rendering needed
             return;
         }
 
         // render main sink document content
         renderer.mergeDocumentIntoSite(writer, mainSink, siteRenderingContext);
 
         // render sub-sinks, eventually created by multi-page reports
         String outputName = "";
         try {
             List<MultiPageSubSink> sinks = multiPageSinkFactory.sinks();
 
             log.debug("Multipage report: " + sinks.size() + " subreports");
 
             for (MultiPageSubSink mySink : sinks) {
                 outputName = mySink.getOutputName();
                 log.debug("  Rendering " + outputName);
 
                 // Create directories if necessary
                 if (!mySink.getOutputDir().exists()) {
                     mySink.getOutputDir().mkdirs();
                 }
 
                 File outputFile = new File(mySink.getOutputDir(), outputName);
 
                 try (Writer out = WriterFactory.newWriter(outputFile, siteRenderingContext.getOutputEncoding())) {
                     renderer.mergeDocumentIntoSite(out, mySink, siteRenderingContext);
                     mySink.close();
                     mySink = null;
                 } finally {
                     if (mySink != null) {
                         mySink.close();
                     }
                 }
             }
         } catch (IOException e) {
             throw new RendererException("Cannot create writer to " + outputName, e);
         }
     }
 
     @Override
     public String getOutputName() {
         return renderingContext.getOutputName();
     }
 
     @Override
     public RenderingContext getRenderingContext() {
         return renderingContext;
     }
 
     @Override
     public boolean isOverwrite() {
         // TODO: would be nice to query the report to see if it is modified
         return true;
     }
 
     /**
      * @return true if the current report is external, false otherwise
      */
     @Override
     public boolean isExternalReport() {
         return report.isExternalReport();
     }
 
     public String getReportMojoInfo() {
         return reportMojoInfo;
     }
 }