/*
    * Copyright 2020-2023 The OSHI Project Contributors
    * SPDX-License-Identifier: MIT
    */
   package oshi.software.os;
   
   import java.time.Instant;
   import java.time.LocalDateTime;
   import java.time.ZoneId;
  import java.time.format.DateTimeFormatter;
  import java.util.Locale;
  
  import oshi.annotation.concurrent.Immutable;
  
  /**
   * This class encapsulates information about users who are currently logged in to an operating system.
   */
  @Immutable
  public class OSSession {
      private static final DateTimeFormatter LOGIN_FORMAT = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm", Locale.ROOT);
  
      private final String userName;
      private final String terminalDevice;
      private final long loginTime;
      private final String host;
  
      public OSSession(String userName, String terminalDevice, long loginTime, String host) {
          this.userName = userName;
          this.terminalDevice = terminalDevice;
          this.loginTime = loginTime;
          this.host = host;
      }
  
      /**
       * Gets the login name of the user
       *
       * @return the userName
       */
      public String getUserName() {
          return userName;
      }
  
      /**
       * Gets the terminal device (such as tty, pts, etc.) the user used to log in
       *
       * @return the terminalDevice
       */
      public String getTerminalDevice() {
          return terminalDevice;
      }
  
      /**
       * Gets the time the user logged in
       *
       * @return the loginTime, in milliseconds since the 1970 epoch
       */
      public long getLoginTime() {
          return loginTime;
      }
  
      /**
       * Gets the remote host from which the user logged in
       *
       * @return the host as either an IPv4 or IPv6 representation. If the host is unspecified, may also be an empty
       *         string, depending on the platform.
       */
      public String getHost() {
          return host;
      }
  
      @Override
      public String toString() {
          String loginStr = loginTime == 0 ? "No login"
                  : LocalDateTime.ofInstant(Instant.ofEpochMilli(loginTime), ZoneId.systemDefault()).format(LOGIN_FORMAT);
          String hostStr = "";
          if (!host.isEmpty() && !host.equals("::") && !host.equals("0.0.0.0")) {
              hostStr = ", (" + host + ")";
          }
          return String.format(Locale.ROOT, "%s, %s, %s%s", userName, terminalDevice, loginStr, hostStr);
      }
  }