Chapter1.java

import javax.swing.*;              // Import Swing components for GUI
import java.awt.*;                 // Import AWT for layout and graphics
import java.sql.Connection;        // Import for SQL connection
import java.sql.DriverManager;     // Import for managing SQL driver
import java.sql.PreparedStatement; // Import for prepared SQL statements

public class chapter1 extends JFrame {
    private static String username;     // Field to store the username
    private HomePage homePage;          // Reference to the HomePage instance
    private JPanel panel;               // Main panel for the GUI
    private JTextArea questionLabel;    // Text area for displaying questions
    private JRadioButton[] options;     // Array of radio buttons for answer options
    private ButtonGroup group;          // Group to manage radio button selection
    private JButton nextButton;         // Button to go to the next question
    private JButton previousButton;     // Button to go back to the previous question

    @Override
    public void setVisible(boolean b) {
        super.setVisible(b); // Call the superclass method to set visibility
    }

    // Array of questions for the quiz
    private String[] questions = {
            "What is the main function of an operating system (OS) in a computer?",
            "Which of these is NOT an example of an operating system?",
            "What is the purpose of the Java Development Kit (JDK)?",
            "In Java, what is the purpose of the 'main' method?",
            "Which of the following is a reserved word in Java?",
            "In Java, which character is used to terminate each statement?",
            "What type of error is caused by dividing a number by zero in Java?",
            "What is 'bytecode' in the Java programming process?",
            "Which tool would you use to create, compile, and run Java programs?",
            "What is a common practice for enhancing readability in Java code?"
    };

    // 2D array of answer options for each question
    private String[][] optionsForQuestions = {
            {"A. Runs application programs without errors", "B. Manages and controls the computer’s activities", "C. Provides internet access", "D. Compiles programming code"},
            {"A. Microsoft Windows", "B. Mac OS", "C. Google Chrome", "D. Linux"},
            {"A. Provides a runtime environment for Java programs", "B. Allows Java code to be written and executed", "C. Manages operating systems", "D. Is used exclusively for debugging Java programs"},
            {"A. Stores data for the program", "B. Starts the execution of a Java program", "C. Compiles the program", "D. Displays errors in the code"},
            {"A. System", "B. Main", "C. Class", "D. Print"},
            {"A. Colon (:)", "B. Period (.)", "C. Semicolon (;)", "D. Exclamation mark (!)" },
            {"A. Syntax error", "B. Runtime error", "C. Logic error", "D. None of the above"},
            {"A. The final executable code", "B. A compiled form of Java code", "C. A code generated by the OS", "D. A code that causes syntax errors"},
            {"A. Notepad", "B. Browser", "C. IDE", "D. File Manager"},
            {"A. Using single spaces between lines of code", "B. Indenting two spaces and using blank lines to separate code segments", "C. Writing all code in a single line", "D. Avoiding comments to reduce code length"}
    };

    private String[] correctAnswers = {"B", "C", "B", "B", "C", "C", "B", "B", "C", "B"}; // Array of correct answers
    private int currentQuestionIndex = 0; // Index of the current question
    private int score = 0; // User's score
    private String[] selectedAnswers = new String[10]; // Array to store user's selected answers

    // Constructor for the chapter1 class
    public chapter1(String username, HomePage homePage) {
        this.username = username; // Initialize username
        this.homePage = homePage; // Initialize homePage reference
        setTitle("Java Quiz - Chapter 1"); // Set the window title
        setSize(800, 600); // Set the window size
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); // Close application on exit
        getContentPane().setBackground(new Color(50, 64, 113)); // Set background color

        panel = new JPanel(); // Create a new panel
        panel.setLayout(null); // Use absolute positioning for custom placements
        panel.setOpaque(false); // Make the panel transparent

        // Set up the question label
        questionLabel = new JTextArea();
        questionLabel.setFont(new Font("Arial Rounded MT Bold", Font.PLAIN, 24)); // Set font style and size
        questionLabel.setForeground(Color.WHITE); // Set text color
        questionLabel.setOpaque(false); // Make it transparent
        questionLabel.setEditable(false); // Make it non-editable
        questionLabel.setLineWrap(true); // Enable line wrapping
        questionLabel.setWrapStyleWord(true); // Wrap at word boundaries
        questionLabel.setBounds(50, 50, 700, 100); // Set position and size
        panel.add(questionLabel); // Add to the panel

        options = new JRadioButton[4]; // Initialize the options array
        group = new ButtonGroup(); // Initialize the button group

        // Create radio buttons for answer options
        for (int i = 0; i < 4; i++) {
            options[i] = new JRadioButton(); // Create a new radio button
            options[i].setFont(new Font("Arial Rounded MT Bold", Font.PLAIN, 18)); // Set font
            options[i].setForeground(Color.WHITE); // Set text color
            options[i].setBackground(new Color(50, 64, 113)); // Set background color
            options[i].setBounds(50, 150 + i * 50, 700, 30); // Set position and size
            group.add(options[i]); // Add to the button group
            panel.add(options[i]); // Add to the panel
        }

        // Set up the Next button
        nextButton = new RoundedButton("Next");
        nextButton.setBounds(350, 450, 150, 50); // Set position and size
        nextButton.addActionListener(e -> { // Add action listener for Next button
            storeSelectedAnswer(); // Store the selected answer
            if (currentQuestionIndex < questions.length - 1) {
                currentQuestionIndex++; // Move to the next question
                displayQuestion(); // Display the new question
            } else {
                calculateFinalScore(); // Calculate the final score
                storeProgressInFile(username, score); // Store progress in the database
                if (score >= 8) {
                    new congrats1(username, homePage, score); // Open the congratulations screen
                } else {
                    new GameOver1(username); // Open the game over screen
                }
                dispose(); // Close the current frame
            }
        });
        panel.add(nextButton); // Add Next button to the panel

        // Set up the Previous button
        previousButton = new RoundedButton("Previous");
        previousButton.setBounds(130, 450, 150, 50); // Set position and size
        previousButton.addActionListener(e -> { // Add action listener for Previous button
            storeSelectedAnswer(); // Store the selected answer
            if (currentQuestionIndex > 0) {
                currentQuestionIndex--; // Move to the previous question
                displayQuestion(); // Display the new question
            }
        });
        panel.add(previousButton); // Add Previous button to the panel

        displayQuestion(); // Display the first question
        add(panel); // Add the main panel to the frame
        setVisible(true); // Make the frame visible
    }

    // Method to display the current question and options
    private void displayQuestion() {
        questionLabel.setText("Question " + (currentQuestionIndex + 1) + ": " + questions[currentQuestionIndex]); // Update the question text
        group.clearSelection(); // Clear previous selections
        for (int i = 0; i < 4; i++) {
            options[i].setText(optionsForQuestions[currentQuestionIndex][i]); // Set text for each option
            // Check if the answer was previously selected
            if (selectedAnswers[currentQuestionIndex] != null && selectedAnswers[currentQuestionIndex].equals(String.valueOf((char) ('A' + i)))) {
                options[i].setSelected(true); // Select the radio button
            }
        }
    }

    // Method to store the selected answer
    private void storeSelectedAnswer() {
        String selectedOption = ""; // Variable to hold the selected option
        for (int i = 0; i < 4; i++) {
            if (options[i].isSelected()) {
                selectedOption = String.valueOf((char) ('A' + i)); // Get the selected option
                break; // Exit the loop once found
            }
        }
        selectedAnswers[currentQuestionIndex] = selectedOption; // Store the selected answer
    }

    // Method to calculate the final score based on selected answers
    private void calculateFinalScore() {
        score = 0; // Reset score
        for (int i = 0; i < selectedAnswers.length; i++) {
            // Check if selected answer is correct
            if (selectedAnswers[i] != null && selectedAnswers[i].equals(correctAnswers[i])) {
                score++; // Increment score for correct answers
            }
        }
    }

    // Method to store progress in the database
    private void storeProgressInFile(String username, int score) {
        // Print the score and username for debugging
        System.out.println(score + "   " + username);
        if (score >= 8) { // Check if the score is sufficient for completion
            String url = "jdbc:mysql://localhost:3306/java"; // Database URL
            String dbUser = "root"; // Database username
            String dbPassword = "#mnta$mn$ta07.inn05/22"; // Database password

            try {
                // Establish a connection to the database
                Connection connection = DriverManager.getConnection(url, dbUser, dbPassword);
                String sql = "update users set chapter1_score =? where username = ?"; // SQL query to update score
                PreparedStatement preparedStatement = connection.prepareStatement(sql);
                preparedStatement.setInt(1, score); // Set score parameter
                preparedStatement.setString(2, username); // Set username parameter
                int noodrecordsupdated = preparedStatement.executeUpdate(); // Execute the update
                System.out.println(noodrecordsupdated); // Print number of records updated
            } catch (Exception e) {
                e.printStackTrace(); // Print any exceptions for debugging
            }
        }
    }

    // Main method to launch the chapter1 quiz
    public static void main(String[] args) {
        new chapter1("testUser", new HomePage()); // Create an instance of chapter1 with a test username
    }

    // Inner class for creating rounded buttons
    static class RoundedButton extends JButton {
        public RoundedButton(String text) {
            super(text); // Call superclass constructor
            setBackground(hexToColor("#fbb748")); // Set button background color
            setForeground(Color.WHITE); // Set text color
            setBorderPainted(false); // Disable border painting
            setFocusPainted(false); // Disable focus painting
            setContentAreaFilled(false); // Disable content area filling
            setFont(new Font("Arial Rounded MT Bold", Font.PLAIN, 16)); // Set font
            setMargin(new Insets(0, 0, 0, 0)); // Set margin to zero
            setOpaque(false); // Make the button transparent
            setBorder(BorderFactory.createEmptyBorder()); // Set an empty border
        }

        // Custom paint method to create rounded corners
        protected void paintComponent(Graphics g) {
            g.setColor(getBackground()); // Set background color
            g.fillRoundRect(0, 0, getWidth(), getHeight(), 30, 30); // Draw rounded rectangle
            super.paintComponent(g); // Call superclass paint method
        }
    }

    // Utility method to convert hex color string to Color object
    private static Color hexToColor(String hex) {
        return new Color(
                Integer.parseInt(hex.substring(1, 3), 16), // Red component
                Integer.parseInt(hex.substring(3, 5), 16), // Green component
                Integer.parseInt(hex.substring(5, 7), 16)  // Blue component
        );
    }
}