import javax.swing.*;
import javax.swing.border.EmptyBorder;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.util.ArrayList;

final class Gui extends JFrame {
  static String message;
  static String answer;
  private String alertMessage;
  private String guesses;
  private Display display;
  private JTextArea textArea;
  private JButton startButton;
  private JButton submitButton;
  private JLabel timerLabel;
  private JButton pauseButton;
  private JButton quitButton;
  private JButton previousButton;
  private JButton sendButton;
  private JButton nextButton;
  private int badGuesses;
  private boolean gameOver;
  private Timer timer;
  private ArrayList<JButton> alphabetButtons = new ArrayList<>();

  Gui() {
    createWindow();
  }

  public enum GuiText {
    START("Start"),
    QUIT("Quit"),
    SKIP("Skip"),
    SUBMIT("Submit"),
    RESET("Reset"),
    SEND("Send"),
    NEXT(">"),
    PREVIOUS("<"),
    PAUSE("Pause");

    private String guiText;

    GuiText(String guiText) {
      this.guiText = guiText;
    }

    @Override
    public String toString() {
      return guiText;
    }
  }

  /**
   * This class defines the panel that occupies the large central area in the
   * main panel.  The paintComponent() method in this class is responsible for
   * drawing the content of that panel.  It shows everything that that the user
   * is supposed to see, based on the current values of all the instance variables.
   */
  private class Display extends JPanel {
    Display() {
      setPreferredSize(new Dimension(1000, 250));
      setBackground(new Color(0x00bcda));
      setFont(new Font("Tahoma", Font.BOLD, 20));
    }

    protected void paintComponent(Graphics g) {
      super.paintComponent(g);
      ((Graphics2D) g).setStroke(new BasicStroke(3));
      if (message != null) {
        g.setColor(Color.DARK_GRAY);
        g.drawString(message, 30, 120);
      }
      if (alertMessage != null) {
        g.setColor(Color.DARK_GRAY);
        g.drawString(alertMessage, 30, 150);
      }
      if (gameOver) {
        alertMessage = "Click on \"Next\" to play again.";
      } else {
        g.drawString("Guesses remaining:  " + (3 - badGuesses), 770, 40);
      }
      g.setColor(Color.DARK_GRAY);
      if (answer != null) {
        for (int i = 0; i < answer.length(); i++) {
          if (String.valueOf(answer.charAt(i)).trim().length() > 0) {
            g.drawLine(30 + i * 70, 210, 70 + i * 70, 210);
            if (guesses.indexOf(answer.charAt(i)) >= 0) {
              g.drawString(String.valueOf(answer.charAt(i)), 45 + i * 70, 195);
            }
          }
        }
      }
    }
  }

  /**
   * The constructor that creates the main panel, which is represented
   * by this class.  It makes all the buttons and subpanels and adds
   * them to the main panel.
   */
  private void createWindow() {
    setJMenuBar(menuBarCreator());

    // The ActionListener that will respond to button clicks.
    ButtonHandler buttonHandler = new ButtonHandler();

    // Create the subpanels and add them to the main panel.
    display = new Display();
    setLayout(new BorderLayout(3, 3));
    add(display, BorderLayout.CENTER);

    // Add timer panel
    JPanel timerPanel = new JPanel();
    timerPanel.setBorder(new EmptyBorder(0, 0, 0, 0));
    timerPanel.setBackground(new Color(0x00bcda));
    add(timerPanel, BorderLayout.PAGE_START);

    // Add timer label
    timerLabel = new JLabel("01:00", SwingConstants.RIGHT);
    timerLabel.setFont(new Font("Arial", Font.BOLD, 20));
    timerLabel.setHorizontalAlignment(JLabel.RIGHT);
    GridBagConstraints c = new GridBagConstraints();
    c.gridx = 1;
    c.fill = GridBagConstraints.HORIZONTAL;
    c.gridy = 0;
    timerLabel.setForeground(Color.black);
    timerPanel.add(timerLabel, c);

    // Add left panel
    JPanel leftPanel = new JPanel(new GridBagLayout());
    c = new GridBagConstraints();
    leftPanel.setBorder(new EmptyBorder(25, 25, 25, 5));
    leftPanel.setBackground(new Color(0x00bcda));
    add(leftPanel, BorderLayout.WEST);

    // Add previous button
    previousButton = new JButton(String.valueOf(GuiText.PREVIOUS));
    previousButton.setFont(new Font("Arial", Font.PLAIN, 60));
    previousButton.addActionListener(buttonHandler);
    c.gridx = 1;
    c.fill = GridBagConstraints.HORIZONTAL;
    c.weighty = 0;
    c.gridy = 0;
    leftPanel.add(previousButton, c);

    // Add right panel
    JPanel rightPanel = new JPanel(new GridBagLayout());
    c = new GridBagConstraints();
    c.fill = GridBagConstraints.VERTICAL;
    rightPanel.setBorder(new EmptyBorder(25, 25, 25, 25));
    rightPanel.setBackground(new Color(0x00bcda));
    add(rightPanel, BorderLayout.EAST);

    // Add next button
    nextButton = new JButton(String.valueOf(GuiText.NEXT));
    nextButton.setFont(new Font("Arial", Font.PLAIN, 60));
    nextButton.addActionListener(buttonHandler);
    c.gridx = 1;
    c.gridy = 0;
    rightPanel.add(nextButton, c);

    // Add actual timer
    initialiseTimer();

    // Add bottom panel
    JPanel bottomPanel = new JPanel(new GridBagLayout());
    GridBagConstraints bottomPanelConstraints = new GridBagConstraints();
    bottomPanelConstraints.fill = GridBagConstraints.HORIZONTAL;
    add(bottomPanel, BorderLayout.PAGE_END);
    setBackground(new Color(100, 0, 0));

    // Add primary button panel to bottom panel
    JPanel primaryButtonPanel = new JPanel();
    primaryButtonPanel.setBorder(new EmptyBorder(20, 20, 20, 20));
    primaryButtonPanel.setBackground(new Color(0xFFFFFF));
    c.gridx = 0;
    c.gridy = 3;
    c.fill = GridBagConstraints.HORIZONTAL;
    bottomPanel.add(primaryButtonPanel, c);

    // Add text area
    textArea = new JTextArea(1, 10);
    c.gridx = 0;
    c.gridy = 0;
    c.fill = GridBagConstraints.HORIZONTAL;
    textArea.setFont(new Font("Arial", Font.PLAIN, 24));
    textArea.setBackground(new Color(0xCCCCCC));
    textArea.setEditable(false);
    primaryButtonPanel.add(textArea, c);

    // Add buttons
    sendButton = new JButton(String.valueOf(GuiText.SEND));
    sendButton.addActionListener(buttonHandler);
    sendButton.setFont(new Font("Arial", Font.PLAIN, 24));
    primaryButtonPanel.add(sendButton);

    // Add secondary button panel
    JPanel secondaryButtonPanel = new JPanel();
    secondaryButtonPanel.setBorder(new EmptyBorder(20, 20, 20, 20));
    secondaryButtonPanel.setBackground(new Color(0xFFFFFF));
    c.gridx = 0;
    c.gridy = 4;
    c.fill = GridBagConstraints.HORIZONTAL;
    bottomPanel.add(secondaryButtonPanel, c);

    // Add secondary buttons
    startButton = new JButton(GuiText.START.toString());
    startButton.addActionListener(buttonHandler);
    startButton.setFont(new Font("Arial", Font.PLAIN, 24));
    secondaryButtonPanel.add(startButton);

    pauseButton = new JButton(GuiText.PAUSE.toString());
    pauseButton.setFont(new Font("Arial", Font.PLAIN, 24));
    pauseButton.addActionListener(buttonHandler);
    secondaryButtonPanel.add(pauseButton);

    quitButton = new JButton(GuiText.QUIT.toString());
    quitButton.setFont(new Font("Arial", Font.PLAIN, 24));
    quitButton.addActionListener(buttonHandler);
    secondaryButtonPanel.add(quitButton);

    submitButton = new JButton(GuiText.SUBMIT.toString());
    submitButton.setFont(new Font("Arial", Font.PLAIN, 24));
    submitButton.addActionListener(buttonHandler);
    secondaryButtonPanel.add(submitButton);

    // Add keyboard panel
    JPanel keyboardPanel = new JPanel();
    keyboardPanel.setBorder(new EmptyBorder(20, 20, 20, 20));
    keyboardPanel.setBackground(new Color(0xFFFFFF));
    c.gridx = 0;
    c.gridy = 5;
    c.fill = GridBagConstraints.HORIZONTAL;
    bottomPanel.add(keyboardPanel, c);
    keyboardPanel.setLayout(new GridLayout(3, 10, 5, 5));
    for (char alphabet = 'a'; alphabet <= 'z'; alphabet++) {
      JButton button = new JButton(String.valueOf(alphabet));
      button.addActionListener(buttonHandler);
      button.setFont(new Font("Arial", Font.PLAIN, 20));
      keyboardPanel.add(button);
      alphabetButtons.add(button);
    }

    disablePrimaryButtons();
  }

  private void initialiseTimer() {
    timer = new Timer(1000, new ActionListener() {
      int time = 60;
      @Override
      public void actionPerformed(ActionEvent e) {
        time--;
        timerLabel.setText(format(time / 60) + ":" + format(time % 60));
        if (time == 0) {
          timer = (Timer) e.getSource();
          timer.stop();
        }
      }
    });
  }

  private static String format(int i) {
    String result = String.valueOf(i);
    if (result.length() == 1) {
      result = "0" + result;
    }
    return result;
  }

  private boolean wordIsComplete() {
    String answerWithoutSpaces = answer.replaceAll(" ", "");
    for (int i = 0; i < answerWithoutSpaces.length(); i++) {
      char ch = answerWithoutSpaces.charAt(i);
      if (this.guesses.indexOf(ch) == -1) {
        return false;
      }
    }
    return true;
  }

  private void disablePrimaryButtons() {
    startButton.setEnabled(true);
  }

  private JMenuBar menuBarCreator() {
    // Create the menu bar
    JMenuBar menuBar = new JMenuBar();
    JMenu menuFile = new JMenu("File");
    JMenu menuHelp = new JMenu("Help");

    JMenuItem menuFileExit = new JMenuItem("Exit");
    JMenuItem menuHelpAbout = new JMenuItem("About");
    JMenuItem menuHelpRules = new JMenuItem("Rules");

    // Exit action
    menuFileExit.addActionListener(e -> System.exit(0));

    // Make the shortcuts for the items
    menuFile.setMnemonic(KeyEvent.VK_F);
    menuHelp.setMnemonic(KeyEvent.VK_H);

    // Out the menu parts with each other
    menuBar.add(menuFile);
    menuBar.add(menuHelp);
    menuFile.add(menuFileExit);
    menuHelp.add(menuHelpRules);
    menuHelp.add(menuHelpAbout);
    menuHelp.add(menuHelpRules);

    return menuBar;
  }

  /**
   * This class defines a listener that will respond to the events that occur
   * when the user clicks any of the buttons in the button.  The buttons are
   * labeled "Next word", "Give up", "Quit", "A", "B", "C", ..., "Z".
   */
  private class ButtonHandler implements ActionListener {
    @Override
    public void actionPerformed(java.awt.event.ActionEvent e) {
      // The text from the button that the user clicked.
      String cmd = e.getActionCommand();
      // Respond to Quit button by ending the program.
      if (cmd.equals(GuiText.QUIT.toString())) {
        System.exit(0);
      } else if (cmd.equals(GuiText.START.toString())) {
        timer.start();
        startGame();
      } else if (cmd.equals(GuiText.NEXT.toString())) {
        timer.stop();
        initialiseTimer();
        timer.start();
        alertMessage = "";
        guesses = "";
        QuestionList.selectRandomQuestion();
      } else if (cmd.equals(GuiText.SUBMIT.toString())) {
        processQuestionResponse(textArea.getText());
      } else if (cmd.equals(GuiText.RESET.toString())) {
        textArea.setText("");
      } else {
        textArea.setText(cmd);
      }
      // Causes the display to be redrawn, to show any changes made.
      display.repaint();
    }
  }

  private void startGame() {
    this.guesses = "";
    this.badGuesses = 0;
    QuestionList.loadQuestions();
    QuestionList.selectRandomQuestion();
  }

  private void processQuestionResponse(String response) {
    char guess = response.toUpperCase().charAt(0);
    guesses = String.valueOf(guesses) + guess;
    if (wordIsComplete()) {
      alertMessage = "Correct answer! Click on \"Next\" to play again.";
      nextButton.setEnabled(true);
      for (JButton b : alphabetButtons)
        b.setEnabled(false);
    } else if (answer.indexOf(guess) >= 0) {
      alertMessage = String.format("Yes, %s is in the word. Pick your next letter.", guess);
    } else {
      badGuesses = badGuesses + 1;
      if (badGuesses == 3) {
        alertMessage = String.format("Sorry, you're hung! The answer was '%s'", answer);
        nextButton.setEnabled(true);
        for (JButton b : alphabetButtons)
          b.setEnabled(false);
        gameOver = true;
      } else {
        alertMessage = String.format("Sorry, %s is not in the word. Pick your next letter.", guess);
      }
    }
    display.repaint();
  }
}