/*
    * 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.model;
  
  import java.util.Date;
  
  /**
   * @author Christian Bauer
   */
  public class ExpirationDetails {
  
      public static final int UNLIMITED_AGE = 0;
  
      private int maxAgeSeconds = UNLIMITED_AGE;
      private long lastRefreshTimestampSeconds = getCurrentTimestampSeconds();
  
      public ExpirationDetails() {
      }
  
      public ExpirationDetails(int maxAgeSeconds) {
          this.maxAgeSeconds = maxAgeSeconds;
      }
  
      public int getMaxAgeSeconds() {
          return maxAgeSeconds;
      }
  
      public long getLastRefreshTimestampSeconds() {
          return lastRefreshTimestampSeconds;
      }
  
      public void setLastRefreshTimestampSeconds(long lastRefreshTimestampSeconds) {
          this.lastRefreshTimestampSeconds = lastRefreshTimestampSeconds;
      }
  
      public void stampLastRefresh() {
          setLastRefreshTimestampSeconds(getCurrentTimestampSeconds());
      }
  
      public boolean hasExpired() {
          return hasExpired(false);
      }
  
      /**
       * @param halfTime If <code>true</code> then half maximum age is used to determine expiration.
       * @return <code>true</code> if the maximum age has been reached.
       */
      public boolean hasExpired(boolean halfTime) {
          // Note: Uses direct field access for performance reasons on Android
          return maxAgeSeconds != UNLIMITED_AGE &&
                  (lastRefreshTimestampSeconds + (maxAgeSeconds/(halfTime ? 2 : 1))) < getCurrentTimestampSeconds();
      }
  
      public long getSecondsUntilExpiration() {
          // Note: Uses direct field access for performance reasons on Android
          return maxAgeSeconds == UNLIMITED_AGE
                  ? Integer.MAX_VALUE
                  : (lastRefreshTimestampSeconds + maxAgeSeconds) - getCurrentTimestampSeconds();
      }
  
      protected long getCurrentTimestampSeconds() {
          return new Date().getTime()/1000;
      }
  
      // Performance optimization on Android
      private static  String simpleName = ExpirationDetails.class.getSimpleName();
  	@Override
      public String toString() {
          return "(" + simpleName + ")" + " MAX AGE: " + maxAgeSeconds;
      }
  }