package name.neuhalfen.projects.crypto.bouncycastle.openpgp.reencryption;

import java.io.IOException;
import java.io.OutputStream;
import javax.annotation.Nullable;

/**
 * Strategy for handling the content of an encrypted ZIP file. <p> The data flow is: <p> [encrypted
 * data from e.g test.zip.gpg] * for each file/dir -- [name sanitation] --
 * ZipEntityStrategy::handleDirectory -- e.g. create directory OR -- output :=
 * ZipEntityStrategy::createOutputStream -- e.g. create a FileOutputStream --
 * writeEncryptedFileContent(output)
 */
public interface ZipEntityStrategy {


  /**
   * Sanitize the names of entities in ZIP files. These can contain absolute paths, and path
   * traversals.
   *
   * @param nameFromZip name of the file/directory as seen in the ZIP
   *
   * @return rewritten name
   */
  String rewriteName(String nameFromZip);

  /**
   * Handle a directory. The names are guaranteed to have be sanitized by  {@link
   * #rewriteName(String)}
   *
   * @param sanitizedDirectoryName Name of the directory as returned by {@link
   *     #rewriteName(String)}
   *
   * @throws IOException Well, can happen
   */
  void handleDirectory(String sanitizedDirectoryName) throws IOException;

  /**
   * Create an outputstream that will receive the (re-)encrypted  content of one file in the ZIP
   *
   * @param sanitizedFileName Name of the file as returned by {@link #rewriteName(String)}
   *
   * @return data sink. Null: Ignore the file
   *
   * @throws IOException Well, can happen
   */
  @Nullable
  OutputStream createOutputStream(String sanitizedFileName) throws IOException;
}