content: /*
   This file is part of Airsonic.
  
   Airsonic is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation, either version 3 of the License, or
   (at your option) any later version.
  
   Airsonic 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 General Public License
   along with Airsonic.  If not, see <http://www.gnu.org/licenses/>.
  
   Copyright 2016 (C) Airsonic Authors
   Based upon Subsonic, Copyright 2009 (C) Sindre Mehus
   */
  package org.airsonic.player.util;
  
  import com.fasterxml.jackson.core.JsonProcessingException;
  import com.fasterxml.jackson.core.type.TypeReference;
  import com.fasterxml.jackson.databind.DeserializationFeature;
  import com.fasterxml.jackson.databind.ObjectMapper;
  import org.apache.commons.lang3.SystemUtils;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  import org.springframework.util.MultiValueMap;
  import org.springframework.web.util.UriComponentsBuilder;
  
  import javax.servlet.ServletResponse;
  import javax.servlet.http.HttpServletRequest;
  import javax.servlet.http.HttpServletResponse;
  import javax.validation.ConstraintViolation;
  import javax.validation.Validation;
  import javax.validation.Validator;
  import javax.validation.ValidatorFactory;
  
  import java.util.*;
  
  /**
   * Miscellaneous general utility methods.
   *
   * @author Sindre Mehus
   */
  public final class Util {
  
      private static final Logger LOG = LoggerFactory.getLogger(Util.class);
      private static final String URL_SENSITIVE_REPLACEMENT_STRING = "<hidden>";
  
      /**
       * Disallow external instantiation.
       */
      private Util() {
      }
  
      public static String getDefaultMusicFolder() {
          String def = isWindows() ? "c:\\music" : "/var/music";
          return System.getProperty("airsonic.defaultMusicFolder", def);
      }
  
      public static String getDefaultPodcastFolder() {
          String def = isWindows() ? "c:\\music\\Podcast" : "/var/music/Podcast";
          return System.getProperty("airsonic.defaultPodcastFolder", def);
      }
  
      public static String getDefaultPlaylistFolder() {
          String def = isWindows() ? "c:\\playlists" : "/var/playlists";
          return System.getProperty("airsonic.defaultPlaylistFolder", def);
      }
  
      public static boolean isWindows() {
          return SystemUtils.IS_OS_WINDOWS;
      }
  
      /**
       * Similar to {@link ServletResponse#setContentLength(int)}, but this
       * method supports lengths bigger than 2GB.
       * <p/>
       * See http://blogger.ziesemer.com/2008/03/suns-version-of-640k-2gb.html
       *
       * @param response The HTTP response.
       * @param length   The content length.
       */
      public static void setContentLength(HttpServletResponse response, long length) {
          if (length <= Integer.MAX_VALUE) {
              response.setContentLength((int) length);
          } else {
              response.setHeader("Content-Length", String.valueOf(length));
          }
      }
  
      public static <T> List<T> subList(List<T> list, long offset, long max) {
          return list.subList((int) offset, Math.min(list.size(), (int) (offset + max)));
      }
  
      public static List<Integer> toIntegerList(int[] values) {
          if (values == null) {
              return Collections.emptyList();
          }
          List<Integer> result = new ArrayList<Integer>(values.length);
          for (int value : values) {
              result.add(value);
          }
          return result;
      }
  
      public static int[] toIntArray(List<Integer> values) {
          if (values == null) {
              return new int[0];
          }
          int[] result = new int[values.size()];
          for (int i = 0; i < result.length; i++) {
              result[i] = values.get(i);
          }
          return result;
      }
  
      private static ObjectMapper objectMapper = new ObjectMapper();
      static {
          objectMapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
      }
  
      public static String debugObject(Object object) {
          try {
              return objectMapper.writerWithDefaultPrettyPrinter().writeValueAsString(object);
          } catch (JsonProcessingException e) {
              LOG.warn("Cant output debug object", e);
              return "";
          }
      }
  
      /**
       * Return a complete URL for the given HTTP request,
       * including the query string.
       *
       * @param request An HTTP request instance
       * @return The associated URL
       */
      public static String getURLForRequest(HttpServletRequest request) {
          String url = request.getRequestURL().toString();
          String queryString = request.getQueryString();
          if (queryString != null && !queryString.isEmpty()) url += "?" + queryString;
          return url;
      }
  
      /**
       * Return an URL for the given HTTP request, with anonymized sensitive parameters.
       *
       * @param request An HTTP request instance
       * @return The associated anonymized URL
       */
      public static String getAnonymizedURLForRequest(HttpServletRequest request) {
  
          String url = getURLForRequest(request);
          UriComponentsBuilder builder = UriComponentsBuilder.fromUriString(url);
          MultiValueMap<String, String> components = builder.build().getQueryParams();
  
          // Subsonic REST API authentication (see RESTRequestParameterProcessingFilter)
          if (components.containsKey("p")) builder.replaceQueryParam("p", URL_SENSITIVE_REPLACEMENT_STRING);  // Cleartext password
          if (components.containsKey("t")) builder.replaceQueryParam("t", URL_SENSITIVE_REPLACEMENT_STRING);  // Token
          if (components.containsKey("s")) builder.replaceQueryParam("s", URL_SENSITIVE_REPLACEMENT_STRING);  // Salt
          if (components.containsKey("u")) builder.replaceQueryParam("u", URL_SENSITIVE_REPLACEMENT_STRING);  // Username
  
          return builder.build().toUriString();
      }
  
      /**
       * Return true if the given object is an instance of the class name in argument.
       * If the class doesn't exist, returns false.
       */
      public static boolean isInstanceOfClassName(Object o, String className) {
          try {
              return Class.forName(className).isInstance(o);
          } catch (ClassNotFoundException e) {
              return false;
          }
      }
  
      public static Map<String, String> objectToStringMap(Object object) {
          TypeReference<HashMap<String, String>> typeReference = new TypeReference<HashMap<String, String>>() {};
          return objectMapper.convertValue(object, typeReference);
      }
  
      public static <T> T stringMapToObject(Class<T> clazz, Map<String, String> data) {
          return objectMapper.convertValue(data, clazz);
      }
  
      private static Validator validator;
      static {
          ValidatorFactory factory = Validation.buildDefaultValidatorFactory();
          validator = factory.getValidator();
      }
  
      public static <T> T stringMapToValidObject(Class<T> clazz, Map<String, String> data) {
          T object = stringMapToObject(clazz, data);
          Set<ConstraintViolation<T>> validate = validator.validate(object);
          if (validate.isEmpty()) {
              return object;
          } else {
              throw new IllegalArgumentException("Created object was not valid");
          }
      }
  }
  