content: /*
   ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
   ~                                                                               ~
   ~ The MIT License (MIT)                                                         ~
   ~                                                                               ~
   ~ Copyright (c) 2015-2025 miaixz.org OSHI and other contributors.               ~
   ~                                                                               ~
   ~ Permission is hereby granted, free of charge, to any person obtaining a copy  ~
   ~ of this software and associated documentation files (the "Software"), to deal ~
   ~ in the Software without restriction, including without limitation the rights  ~
   ~ to use, copy, modify, merge, publish, distribute, sublicense, and/or sell     ~
   ~ copies of the Software, and to permit persons to whom the Software is         ~
   ~ furnished to do so, subject to the following conditions:                      ~
   ~                                                                               ~
   ~ The above copyright notice and this permission notice shall be included in    ~
   ~ all copies or substantial portions of the Software.                           ~
   ~                                                                               ~
   ~ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR    ~
   ~ IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,      ~
   ~ FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE   ~
   ~ AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER        ~
   ~ LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, ~
   ~ OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN     ~
   ~ THE SOFTWARE.                                                                 ~
   ~                                                                               ~
   ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
  */
  package org.miaixz.bus.health.unix.platform.aix.driver;
  
  import java.time.LocalDateTime;
  import java.time.ZoneId;
  import java.time.format.DateTimeFormatter;
  import java.time.format.DateTimeParseException;
  import java.util.Locale;
  import java.util.regex.Matcher;
  import java.util.regex.Pattern;
  
  import org.miaixz.bus.core.lang.Symbol;
  import org.miaixz.bus.core.lang.annotation.ThreadSafe;
  import org.miaixz.bus.health.Executor;
  
  /**
   * Utility to query logged in users.
   *
   * @author Kimi Liu
   * @since Java 17+
   */
  @ThreadSafe
  public final class Who {
  
      // sample format:
      // system boot 2020-06-16 09:12
      private static final Pattern BOOT_FORMAT_AIX = Pattern.compile("\\D+(\\d{4}-\\d{2}-\\d{2})\\s+(\\d{2}:\\d{2}).*");
      private static final DateTimeFormatter BOOT_DATE_FORMAT_AIX = DateTimeFormatter
              .ofPattern("yyyy-MM-dd HH:mm", Locale.ROOT);
  
      private Who() {
      }
  
      /**
       * Query {@code who -b} to get boot time
       *
       * @return Boot time in milliseconds since the epoch
       */
      public static long queryBootTime() {
          String s = Executor.getFirstAnswer("who -b");
          if (s.isEmpty()) {
              s = Executor.getFirstAnswer("/usr/bin/who -b");
          }
          Matcher m = BOOT_FORMAT_AIX.matcher(s);
          if (m.matches()) {
              try {
                  return LocalDateTime.parse(m.group(1) + Symbol.SPACE + m.group(2), BOOT_DATE_FORMAT_AIX)
                          .atZone(ZoneId.systemDefault()).toInstant().toEpochMilli();
              } catch (DateTimeParseException | NullPointerException e) {
                  // Shouldn't happen with regex matching
              }
          }
          return 0L;
      }
  
  }
  