package horstmann.ch02_mail;
/**
   Connects a phone to the mail system. The purpose of this
   class is to keep track of the state of a connection, since
   the phone itself is just a source of individual key presses.
 */
@SuppressWarnings("all")
public class Connection
{
  /**
      Construct a Connection object.
      @param s a MailSystem object
      @param p a Telephone object
   */
  public Connection(MailSystem s, Telephone p)
  {
    system = s;
    phone = p;
    resetConnection();
  }

  /**
      Respond to the user's pressing a key on the phone touchpad
      @param key the phone key pressed by the user
   */
  public void dial(String key)
  {
    if (state == CONNECTED)
      connect(key);
    else if (state == RECORDING)
      login(key);
    else if (state == CHANGE_PASSCODE)
      changePasscode(key);
    else if (state == CHANGE_GREETING)
      changeGreeting(key);
    else if (state == MAILBOX_MENU)
      mailboxMenu(key);
    else if (state == MESSAGE_MENU)
      messageMenu(key);
  }

  /**
      Record voice.
      @param voice voice spoken by the user
   */
  public void record(String voice)
  {
    if (state == RECORDING || state == CHANGE_GREETING)
      currentRecording += voice;
  }

  /**
      The user hangs up the phone.
   */
  public void hangup()
  {
    if (state == RECORDING)
      currentMailbox.addMessage(new Message(currentRecording));
    resetConnection();
  }

  /**
      Reset the connection to the initial state and prompt
      for mailbox number
   */
  private void resetConnection()
  {
    currentRecording = "";
    accumulatedKeys = "";
    state = CONNECTED;
    phone.speak(INITIAL_PROMPT);
  }

  /**
      Try to connect the user with the specified mailbox.
      @param key the phone key pressed by the user
   */
  private void connect(String key)
  {
    if (key.equals("#"))
    {
      currentMailbox = system.findMailbox(accumulatedKeys);
      if (currentMailbox != null)
      {
        state = RECORDING;
        phone.speak(currentMailbox.getGreeting());
      }
      else
        phone.speak("Incorrect mailbox number. Try again!");
      accumulatedKeys = "";
    }
    else
      accumulatedKeys += key;
  }

  /**
      Try to log in the user.
      @param key the phone key pressed by the user
   */
  private void login(String key)
  {
    if (key.equals("#"))
    {
      if (currentMailbox.checkPasscode(accumulatedKeys))
      {
        state = MAILBOX_MENU;
        phone.speak(MAILBOX_MENU_TEXT);
      }
      else
        phone.speak("Incorrect passcode. Try again!");
      accumulatedKeys = "";
    }
    else
      accumulatedKeys += key;
  }

  /**
      Change passcode.
      @param key the phone key pressed by the user
   */
  private void changePasscode(String key)
  {
    if (key.equals("#"))
    {
      currentMailbox.setPasscode(accumulatedKeys);
      state = MAILBOX_MENU;
      phone.speak(MAILBOX_MENU_TEXT);
      accumulatedKeys = "";
    }
    else
      accumulatedKeys += key;
  }

  /**
      Change greeting.
      @param key the phone key pressed by the user
   */
  private void changeGreeting(String key)
  {
    if (key.equals("#"))
    {
      currentMailbox.setGreeting(currentRecording);
      currentRecording = "";
      state = MAILBOX_MENU;
      phone.speak(MAILBOX_MENU_TEXT);
    }
  }

  /**
      Respond to the user's selection from mailbox menu.
      @param key the phone key pressed by the user
   */
  private void mailboxMenu(String key)
  {
    if (key.equals("1"))
    {
      state = MESSAGE_MENU;
      phone.speak(MESSAGE_MENU_TEXT);
    }
    else if (key.equals("2"))
    {
      state = CHANGE_PASSCODE;
      phone.speak("Enter new passcode followed by the # key");
    }
    else if (key.equals("3"))
    {
      state = CHANGE_GREETING;
      phone.speak("Record your greeting, then press the # key");
    }
  }

  /**
      Respond to the user's selection from message menu.
      @param key the phone key pressed by the user
   */
  private void messageMenu(String key)
  {
    if (key.equals("1"))
    {
      String output = "";
      Message m = currentMailbox.getCurrentMessage();
      if (m == null) output += "No messages." + "\n";
      else output += m.getText() + "\n";
      output += MESSAGE_MENU_TEXT;
      phone.speak(output);
    }
    else if (key.equals("2"))
    {
      currentMailbox.saveCurrentMessage();
      phone.speak(MESSAGE_MENU_TEXT);
    }
    else if (key.equals("3"))
    {
      currentMailbox.removeCurrentMessage();
      phone.speak(MESSAGE_MENU_TEXT);
    }
    else if (key.equals("4"))
    {
      state = MAILBOX_MENU;
      phone.speak(MAILBOX_MENU_TEXT);
    }
  }

  private MailSystem system;
  private Mailbox currentMailbox;
  private String currentRecording;
  private String accumulatedKeys;
  private Telephone phone;
  private int state;

  private static final int DISCONNECTED = 0;
  private static final int CONNECTED = 1;
  private static final int RECORDING = 2;
  private static final int MAILBOX_MENU = 3;
  private static final int MESSAGE_MENU = 4;
  private static final int CHANGE_PASSCODE = 5;
  private static final int CHANGE_GREETING = 6;

  private static final String INITIAL_PROMPT =
      "Enter mailbox number followed by #";
  private static final String MAILBOX_MENU_TEXT =
      "Enter 1 to listen to your messages\n"
          + "Enter 2 to change your passcode\n"
          + "Enter 3 to change your greeting";
  private static final String MESSAGE_MENU_TEXT =
      "Enter 1 to listen to the current message\n"
          + "Enter 2 to save the current message\n"
          + "Enter 3 to delete the current message\n"
          + "Enter 4 to return to the main menu";
}