/*
    * Copyright 2020-2022 The OSHI Project Contributors
    * SPDX-License-Identifier: MIT
    */
   package oshi.driver.unix.aix;
   
   import java.util.regex.Matcher;
   import java.util.regex.Pattern;
   
  import oshi.annotation.concurrent.ThreadSafe;
  import oshi.util.ExecutingCommand;
  import oshi.util.ParseUtil;
  
  /**
   * Utility to query up time.
   */
  @ThreadSafe
  public final class Uptime {
  
      private static final long MINUTE_MS = 60L * 1000L;
      private static final long HOUR_MS = 60L * MINUTE_MS;
      private static final long DAY_MS = 24L * HOUR_MS;
  
      // sample format:
      // 18:36pm up 10 days 8:11, 2 users, load average: 3.14, 2.74, 2.41
  
      private static final Pattern UPTIME_FORMAT_AIX = Pattern
              .compile(".*\\sup\\s+((\\d+)\\s+days?,?\\s+)?\\b((\\d+):)?(\\d+)(\\s+min(utes?)?)?,\\s+\\d+\\s+user.+"); // NOSONAR:squid:S5843
  
      private Uptime() {
      }
  
      /**
       * Query {@code uptime} to get up time
       *
       * @return Up time in milliseconds
       */
      public static long queryUpTime() {
          long uptime = 0L;
          String s = ExecutingCommand.getFirstAnswer("uptime");
          if (s.isEmpty()) {
              s = ExecutingCommand.getFirstAnswer("w");
          }
          if (s.isEmpty()) {
              s = ExecutingCommand.getFirstAnswer("/usr/bin/uptime");
          }
          Matcher m = UPTIME_FORMAT_AIX.matcher(s);
          if (m.matches()) {
              if (m.group(2) != null) {
                  uptime += ParseUtil.parseLongOrDefault(m.group(2), 0L) * DAY_MS;
              }
              if (m.group(4) != null) {
                  uptime += ParseUtil.parseLongOrDefault(m.group(4), 0L) * HOUR_MS;
              }
              uptime += ParseUtil.parseLongOrDefault(m.group(5), 0L) * MINUTE_MS;
          }
          return uptime;
      }
  }