package fr.ifremer.quadrige3.synchro.server.resource;
   
   /*-
    * #%L
    * Quadrige3 Core :: Quadrige3 Synchro server
    * $Id:$
    * $HeadURL:$
    * %%
    * Copyright (C) 2017 Ifremer
   * %%
   * This program is free software: you can redistribute it and/or modify
   * it under the terms of the GNU Affero General Public License as published by
   * the Free Software Foundation, either version 3 of the License, or
   * (at your option) any later version.
   * 
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.
   * 
   * You should have received a copy of the GNU Affero General Public License
   * along with this program.  If not, see <http://www.gnu.org/licenses/>.
   * #L%
   */
  
  
  import fr.ifremer.quadrige3.core.dao.technical.Files;
  import fr.ifremer.quadrige3.synchro.server.config.SynchroServerConfiguration;
  import fr.ifremer.quadrige3.synchro.server.security.SecurityContextHelper;
  import org.apache.commons.io.FileUtils;
  import org.apache.commons.io.FilenameUtils;
  import org.apache.commons.lang3.StringUtils;
  import org.apache.wicket.WicketRuntimeException;
  import org.apache.wicket.request.resource.AbstractResource;
  import org.springframework.util.MimeTypeUtils;
  
  import java.io.*;
  
  public class DownloadFileResource extends AbstractResource {
  
      private static final long serialVersionUID = 1L;
  
      private static final String PARAM_TYPE = "type";
      private static final String PARAM_FILE = "file";
  
      @Override
      protected ResourceResponse newResourceResponse(Attributes attributes) {
  
          String type = attributes.getParameters().get(PARAM_TYPE).toString();
          String fileName = attributes.getParameters().get(PARAM_FILE).toString();
          ResourceResponse resourceResponse = new ResourceResponse();
  
          // Make sure type and filename are filled
          if (StringUtils.isBlank(type) || StringUtils.isBlank(fileName)) {
              resourceResponse.setError(404);
              return resourceResponse;
          }
  
          final File file = getFile(type, fileName);
          if (file == null || !file.exists()) {
              resourceResponse.setError(404);
              return resourceResponse;
          }
  
          // Set mime type
          String contentType = "application/download";
          if (FilenameUtils.isExtension(file.getName(), "properties")) {
              contentType = MimeTypeUtils.TEXT_PLAIN.getType();
          }
          resourceResponse.setContentType(contentType);
  
          // Set filename
          resourceResponse.setFileName(fileName);
  
          long fileLength = FileUtils.sizeOf(file);
          resourceResponse.setContentLength(fileLength);
  
          resourceResponse.setWriteCallback(new WriteCallback() {
              @Override
              public void writeData(Attributes attributes) {
  
                  try (OutputStream os = attributes.getResponse().getOutputStream();
                       InputStream is = new BufferedInputStream(new FileInputStream(file))) {
  
                      Files.copyStream(is, os);
  
                  } catch (IOException e) {
                      throw new WicketRuntimeException("Error while writing file content to response", e);
                  }
              }
          });
          
          return resourceResponse;
      }
  
      private File getFile(String type, String filename) {
          SynchroServerConfiguration config = SynchroServerConfiguration.getInstance();
  
          int userId = SecurityContextHelper.getPrincipalUserId();
         if ("import".equalsIgnoreCase(type)) {
             return new File(config.getSynchroImportDirectoryByUser(userId), filename);
         }
         if ("export".equalsIgnoreCase(type)) {
             return new File(config.getSynchroExportDirectoryByUser(userId), filename);
         }
         if ("install".equalsIgnoreCase(type)) {
             return new File(config.getSynchroDirectory(), filename);
         }
 
         return null;
     }
 }