/*
    * Copyright 2012-2025 CodeLibs Project and the Others.
    *
    * Licensed 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.codelibs.fess.helper;
  
  import java.io.IOException;
  import java.nio.file.FileVisitOption;
  import java.nio.file.Files;
  import java.nio.file.Path;
  import java.nio.file.StandardCopyOption;
  import java.util.Comparator;
  import java.util.stream.Stream;
  import java.util.zip.ZipEntry;
  import java.util.zip.ZipInputStream;
  
  import org.apache.logging.log4j.LogManager;
  import org.apache.logging.log4j.Logger;
  import org.codelibs.core.lang.StringUtil;
  import org.codelibs.core.stream.StreamUtil;
  import org.codelibs.fess.exception.ThemeException;
  import org.codelibs.fess.helper.PluginHelper.Artifact;
  import org.codelibs.fess.helper.PluginHelper.ArtifactType;
  import org.codelibs.fess.util.ResourceUtil;
  
  /**
   * Helper class for managing theme installation and uninstallation.
   * Handles the extraction and deployment of theme files from JAR artifacts.
   */
  public class ThemeHelper {
      private static final Logger logger = LogManager.getLogger(ThemeHelper.class);
  
      /**
       * Default constructor for ThemeHelper.
       */
      public ThemeHelper() {
          // Default constructor
      }
  
      /**
       * Installs a theme from the given artifact.
       * Extracts theme files from the JAR and deploys them to appropriate directories.
       *
       * @param artifact the theme artifact to install
       * @throws ThemeException if installation fails
       */
      public void install(final Artifact artifact) {
          final Path jarPath = getJarFile(artifact);
          final String themeName = getThemeName(artifact);
          if (logger.isDebugEnabled()) {
              logger.debug("Theme: name={}", themeName);
          }
          try (ZipInputStream zis = new ZipInputStream(Files.newInputStream(jarPath))) {
              ZipEntry entry;
              while ((entry = zis.getNextEntry()) != null) {
                  if (!entry.isDirectory()) {
                      final String[] names = StreamUtil.split(entry.getName(), "/")
                              .get(stream -> stream.filter(s -> !"..".equals(s)).toArray(n -> new String[n]));
                      if (names.length < 2) {
                          continue;
                      }
                      if (logger.isDebugEnabled()) {
                          logger.debug("Loading entry: name={}", entry.getName());
                      }
                      if ("view".equals(names[0])) {
                          names[0] = themeName;
                          final Path path = ResourceUtil.getViewTemplatePath(names);
                          Files.createDirectories(path.getParent());
                          Files.copy(zis, path, StandardCopyOption.REPLACE_EXISTING);
                      } else if ("css".equals(names[0])) {
                          names[0] = themeName;
                          final Path path = ResourceUtil.getCssPath(names);
                          Files.createDirectories(path.getParent());
                          Files.copy(zis, path, StandardCopyOption.REPLACE_EXISTING);
                      } else if ("js".equals(names[0])) {
                          names[0] = themeName;
                          final Path path = ResourceUtil.getJavaScriptPath(names);
                          Files.createDirectories(path.getParent());
                          Files.copy(zis, path, StandardCopyOption.REPLACE_EXISTING);
                      } else if ("images".equals(names[0])) {
                          names[0] = themeName;
                          final Path path = ResourceUtil.getImagePath(names);
                          Files.createDirectories(path.getParent());
                          Files.copy(zis, path, StandardCopyOption.REPLACE_EXISTING);
                      }
                  }
              }
          } catch (final IOException e) {
             throw new ThemeException("Failed to install " + artifact, e);
         }
     }
 
     /**
      * Uninstalls a theme by removing all its associated files and directories.
      *
      * @param artifact the theme artifact to uninstall
      */
     public void uninstall(final Artifact artifact) {
         final String themeName = getThemeName(artifact);
 
         final Path viewPath = ResourceUtil.getViewTemplatePath(themeName);
         closeQuietly(viewPath);
         final Path imagePath = ResourceUtil.getImagePath(themeName);
         closeQuietly(imagePath);
         final Path cssPath = ResourceUtil.getCssPath(themeName);
         closeQuietly(cssPath);
         final Path jsPath = ResourceUtil.getJavaScriptPath(themeName);
         closeQuietly(jsPath);
     }
 
     /**
      * Extracts the theme name from the artifact name.
      *
      * @param artifact the theme artifact
      * @return the theme name
      * @throws ThemeException if theme name cannot be determined
      */
     protected String getThemeName(final Artifact artifact) {
         final String themeName = artifact.getName().substring(ArtifactType.THEME.getId().length() + 1);
         if (StringUtil.isBlank(themeName)) {
             throw new ThemeException("Theme name is empty: " + artifact);
         }
         return themeName;
     }
 
     /**
      * Recursively deletes a directory and all its contents.
      * Does not throw exceptions, only logs warnings if deletion fails.
      *
      * @param dir the directory to delete
      */
     protected void closeQuietly(final Path dir) {
         if (Files.notExists(dir)) {
             if (logger.isDebugEnabled()) {
                 logger.debug("Path does not exist: path={}", dir);
             }
             return;
         }
         try (Stream<Path> walk = Files.walk(dir, FileVisitOption.FOLLOW_LINKS)) {
             walk.sorted(Comparator.reverseOrder()).forEach(f -> {
                 if (logger.isDebugEnabled()) {
                     logger.debug("Deleting: path={}", f);
                 }
                 try {
                     Files.delete(f);
                 } catch (final IOException e) {
                     logger.warn("Failed to delete: path={}", f, e);
                 }
             });
             Files.deleteIfExists(dir);
         } catch (final IOException e) {
             logger.warn("Failed to delete: path={}", dir, e);
         }
     }
 
     /**
      * Gets the JAR file path for the given artifact.
      *
      * @param artifact the theme artifact
      * @return the path to the JAR file
      * @throws ThemeException if the JAR file does not exist
      */
     protected Path getJarFile(final Artifact artifact) {
         final Path jarPath = ResourceUtil.getPluginPath(artifact.getFileName());
         if (!Files.exists(jarPath)) {
             throw new ThemeException(artifact.getFileName() + " does not exist.");
         }
         return jarPath;
     }
 
 }