package edu.jiangxin.apktoolbox.file.password.recovery.checker;
   
   import org.apache.commons.compress.archivers.sevenz.SevenZArchiveEntry;
   import org.apache.commons.compress.archivers.sevenz.SevenZFile;
   import org.apache.commons.compress.utils.MultiReadOnlySeekableByteChannel;
   import org.apache.commons.io.FilenameUtils;
   import org.apache.commons.io.IOUtils;
   
   import java.io.BufferedInputStream;
  import java.io.File;
  import java.io.IOException;
  import java.nio.channels.SeekableByteChannel;
  import java.util.ArrayList;
  import java.util.List;
  
  public final class SevenZipChecker extends FileChecker {
      private static final boolean DEBUG = true;
  
      private boolean isSplitFile = false;
  
      private File[] splitFiles;
  
      public SevenZipChecker() {
          super();
      }
  
      @Override
      public String[] getFileExtensions() {
          return new String[]{"7z", "001"};
      }
  
      @Override
      public String getFileDescription() {
          return "*.7z";
      }
  
      @Override
      public String getDescription() {
          return "7Zip Checker";
      }
  
      @Override
      public boolean prepareChecker() {
          return true;
      }
  
      @Override
      public void attachFile(File file) {
          super.attachFile(file);
          isSplitFile = isSplitFile();
          splitFiles = getSplitFiles();
      }
  
      @Override
      public boolean checkPassword(String password) {
          if (DEBUG) {
              logger.info("checkPassword: " + password);
          }
          if (isSplitFile) {
              SevenZFile.Builder builder = new SevenZFile.Builder();
              SeekableByteChannel channel = null;
              SevenZFile sevenZFile = null;
              try {
                  channel = MultiReadOnlySeekableByteChannel.forFiles(splitFiles);
                  builder.setSeekableByteChannel(channel).setPassword(password.toCharArray());
                  sevenZFile = builder.get();
                  tryToRead(sevenZFile);
                  return true;
              } catch (IOException e) {
                  return false;
              } finally {
                  IOUtils.closeQuietly(channel);
                  IOUtils.closeQuietly(sevenZFile);
              }
  
          } else {
              SevenZFile sevenZFile = null;
              try {
                  SevenZFile.Builder builder = new SevenZFile.Builder().setFile(file).setPassword(password.toCharArray());
                  builder.setFile(file).setPassword(password.toCharArray());
                  sevenZFile = builder.get();
                  tryToRead(sevenZFile);
                  return true;
              } catch (IOException e) {
                  return false;
              } finally {
                  IOUtils.closeQuietly(sevenZFile);
              }
          }
      }
  
      private void tryToRead(SevenZFile sevenZFile) throws IOException {
          SevenZArchiveEntry entry = sevenZFile.getNextEntry();
          while (entry != null) {
              try (BufferedInputStream bis = new BufferedInputStream(sevenZFile.getInputStream(entry))) {
                  byte[] buffer = new byte[1024];
                  while (bis.read(buffer) != -1) {
                      // do nothing
                  }
             }
             entry = sevenZFile.getNextEntry();
         }
     }
 
     private boolean isSplitFile() {
         String extension = FilenameUtils.getExtension(file.getName());
         logger.info("isSplitFile extension: {}", extension);
         return "001".equals(extension);
     }
 
     private File[] getSplitFiles() {
         List<File> fileList = new ArrayList<>();
         String baseName = FilenameUtils.getBaseName(file.getName());
         String parent = file.getParent();
         logger.info("getSplitFiles baseName: {}", baseName);
         for (int i = 1; i < 1000; i++) {
             File file = new File(parent, baseName + "." + String.format("%03d", i));
             if (file.exists()) {
                 fileList.add(file);
             } else {
                 break;
             }
         }
         logger.info("getSplitFiles: {}", fileList);
         return fileList.toArray(new File[0]);
     }
 }