/*
    * Copyright (C) 2013 4th Line GmbH, Switzerland
    *
    * The contents of this file are subject to the terms of either the GNU
    * Lesser General Public License Version 2 or later ("LGPL") or the
    * Common Development and Distribution License Version 1 or later
    * ("CDDL") (collectively, the "License"). You may not use this file
    * except in compliance with the License. See LICENSE.txt for more
    * information.
   *
   * 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.
   */
  
  package org.fourthline.cling.support.model;
  
  import java.util.ArrayList;
  import java.util.List;
  
  /**
   * @author Christian Bauer
   */
  public class SortCriterion {
  
      final protected boolean ascending;
      final protected String propertyName;
  
      public SortCriterion(boolean ascending, String propertyName) {
          this.ascending = ascending;
          this.propertyName = propertyName;
      }
  
      public SortCriterion(String criterion) {
          this(criterion.startsWith("+"), criterion.substring(1));
          if (!(criterion.startsWith("-") || criterion.startsWith("+")))
              throw new IllegalArgumentException("Missing sort prefix +/- on criterion: " + criterion);
      }
  
      public boolean isAscending() {
          return ascending;
      }
  
      public String getPropertyName() {
          return propertyName;
      }
  
      public static SortCriterion[] valueOf(String s) {
          if (s == null || s.length() == 0) return new SortCriterion[0];
          List<SortCriterion> list = new ArrayList<>();
          String[] criteria = s.split(",");
          for (String criterion : criteria) {
              list.add(new SortCriterion(criterion.trim()));
          }
          return list.toArray(new SortCriterion[list.size()]);
      }
  
      public static String toString(SortCriterion[] criteria) {
          if (criteria == null) return "";
          StringBuilder sb = new StringBuilder();
          for (SortCriterion sortCriterion : criteria) {
              sb.append(sortCriterion.toString()).append(",");
          }
          if (sb.toString().endsWith(",")) sb.deleteCharAt(sb.length()-1);
          return sb.toString();
      }
  
      @Override
      public String toString() {
          StringBuilder sb = new StringBuilder();
          sb.append(ascending ? "+" : "-");
          sb.append(propertyName);
          return sb.toString();
      }
  }