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Canvas.java

@@ -5,61 +5,99 @@ import java.io.*;
 import javax.imageio.*;
 import javax.swing.*;
 
-public class Canvas extends JPanel {
+// Canvas class, which draws the board and also acts as a central location of
+// game state that tiles and the face can refer back to
+public class Canvas extends JComponent {
+	// Width of the tileset
 	public static final int TS_WIDTH = 144;
+	// Height of the tileset
 	public static final int TS_HEIGHT = 122;
+	// Y-position of the digits in the tileset
 	public static final int TS_DIGITS_Y = 33;
+	// Y-position of the faces in the tilest
 	public static final int TS_FACES_Y = 55;
+	// Y-position of the miscellaneous stuff in the tileset
 	public static final int TS_MISC_Y = 82;
+	// X-position of the digit backdrop in the tileset
 	public static final int TS_DIGIT_BACKDROP_X = 28;
+	// X-position of the color pixel in the tileset
 	public static final int TS_COLOR_X = 70;
+	// Width of the borders
 	public static final int BORDER_WIDTH = 12;
+	// Height of most of the borders
 	public static final int BORDER_HEIGHT = 11;
+	// Height of the bottom border
 	public static final int BOTTOM_HEIGHT = 12;
+	// Height of the box at the top, without the borders
 	public static final int TOP_BOX_HEIGHT = 33;
+	// The distance of the top items from the top of the screen
 	public static final int TOP_PADDING = 15;
+	// The distance of the flags display from the left of the screen
 	public static final int FLAGS_PADDING = 16;
+	// The distance of the left side of the timer display from the right of the
+	// screen
 	public static final int TIMER_PADDING = 59;
 
+	// The important game attributes as final ints
 	public final int ROWS;
 	public final int COLS;
 	public final int MINES;
 	public final int WIDTH;
 	public final int HEIGHT;
 
+	// JPanel containing all the tiles
 	private final JPanel BOARD_PANEL;
+	// Number displays for the flags and the time
 	private final NumberDisplay FLAGS_DISPLAY;
 	private final NumberDisplay TIMER_DISPLAY;
+	// The face
 	private final Face FACE;
+	// A KeyListener listening for shift to help chord
 	private final KeyListener SHIFT_KEY_LISTENER;
+	// Timer to tick up the time every second
 	private final Timer TIMER;
+	// The virtual representation of the board if we want to actually reference
+	// the tiles instead of casting BOARD_PANEL.getComponents() becuase that's
+	// weird
 	private final Tile[][] BOARD;
-	private final Image BACKGROUND_IMAGE;
+
+	// The image to draw in the background
+	private Image backgroundImage;
 
 	// The tile that the mouse is currently over
 	private Tile currentTile;
 
+	// Whether the game has started yet (before the first click, no mines exist
+	// and the timer doesn't start)
 	private boolean gameStarted;
+	// Whether the game has ended
 	private boolean gameEnded;
+	// Whether the game was lost
 	private boolean gameLost;
+	// The number of tiles left to reveal, to know when to win
+	private int numTilesLeft;
+	// The number of flags left to place, for the digit display
+	private int numFlagsLeft;
+	// The time, also for the digit display
+	private int time;
+	// Input state; not used direclty, but getters for these exist in Tile, and
+	// this is where we can store the data for the entire game
 	private boolean holdingShift;
 	private boolean leftMouseDown;
 	private boolean rightMouseDown;
-	private int numTilesLeft;
-	private int numFlagsLeft;
-	private int time;
 
+	// Set initial values of all the variables
 	private void init() {
 		currentTile = null;
 		gameStarted = false;
 		gameEnded = false;
 		gameLost = false;
-		holdingShift = false;
-		leftMouseDown = false;
-		rightMouseDown = false;
 		numTilesLeft = ROWS * COLS - MINES;
 		numFlagsLeft = MINES;
 		time = 0;
+		holdingShift = false;
+		leftMouseDown = false;
+		rightMouseDown = false;
 
 		addKeyListener(SHIFT_KEY_LISTENER);
 
@@ -67,17 +105,13 @@ public class Canvas extends JPanel {
 		TIMER_DISPLAY.setNum(time);
 	}
 
-	public Canvas(File skin) {
+	// Get the tileset from Options and use it to set the images of all the
-		Difficulty difficulty = Options.getDifficulty();
+	// components inside the canvas and the background image
-		ROWS = difficulty.getRows();
+	private void setImages() {
-		COLS = difficulty.getCols();
+		// Read the tileset image
-		MINES = difficulty.getMines();
-		WIDTH = Tile.SIZE * COLS + 2 * BORDER_WIDTH;
-		HEIGHT = Tile.SIZE * ROWS + 2 * BORDER_HEIGHT + BOTTOM_HEIGHT + TOP_BOX_HEIGHT;
-
 		BufferedImage tileset;
 		try {
-			tileset = ImageIO.read(skin);
+			tileset = ImageIO.read(new File(Options.SKINS_DIR, Options.getSkinName()));
 			// Reject images that are too small to properly form the tileset
 			if (tileset.getWidth() < TS_WIDTH || tileset.getHeight() < TS_HEIGHT)
 				throw new IOException();
@@ -86,20 +120,47 @@ public class Canvas extends JPanel {
 			tileset = new BufferedImage(TS_WIDTH, TS_HEIGHT, BufferedImage.TYPE_INT_RGB);
 		}
 
-		BACKGROUND_IMAGE = getBackgroundImage(tileset);
+		// Set the images of the tiles
-
 		Image[] numberTiles = new Image[9];
 		Image[] specialTiles = new Image[Tile.EXPLODED_MINE_INDEX + 1];
 		for (int i = 0; i < 9; i++)
 			numberTiles[i] = getTileFromSet(tileset, i, 0);
 		for (int i = 0; i <= Tile.EXPLODED_MINE_INDEX; i++)
 			specialTiles[i] = getTileFromSet(tileset, i, Tile.SIZE);
+		for (Tile[] row : BOARD)
+			for (Tile tile : row)
+				tile.setImages(numberTiles, specialTiles);
 
+		// Set the images of the the number displays
+		Image[] digits = getImageSet(tileset, NumberDisplay.MINUS_INDEX + 1, TS_DIGITS_Y,
+				NumberDisplay.DIGIT_WIDTH, NumberDisplay.DIGIT_HEIGHT);
+		Image numberDisplayBackdrop = tileset.getSubimage(TS_DIGIT_BACKDROP_X, TS_MISC_Y,
+				NumberDisplay.BACKDROP_WIDTH, NumberDisplay.BACKDROP_HEIGHT);
+		FLAGS_DISPLAY.setImages(digits, numberDisplayBackdrop);
+		TIMER_DISPLAY.setImages(digits, numberDisplayBackdrop);
+
+		// Set the images of the face
+		FACE.setImages(getImageSet(tileset, Face.PRESSED_INDEX + 1, TS_FACES_Y, Face.SIZE, Face.SIZE));
+
+		// Set the background image
+		backgroundImage = getBackgroundImage(tileset);
+	}
+
+	public Canvas() {
+		// Set game attributes based on the difficulty
+		Difficulty difficulty = Options.getDifficulty();
+		ROWS = difficulty.getRows();
+		COLS = difficulty.getCols();
+		MINES = difficulty.getMines();
+		WIDTH = Tile.SIZE * COLS + 2 * BORDER_WIDTH;
+		HEIGHT = Tile.SIZE * ROWS + 2 * BORDER_HEIGHT + BOTTOM_HEIGHT + TOP_BOX_HEIGHT;
+
+		// Initialize the tiles
 		BOARD = new Tile[ROWS][COLS];
 		BOARD_PANEL = new JPanel(new GridLayout(ROWS, COLS));
 		for (int r = 0; r < ROWS; r++) {
 			for (int c = 0; c < COLS; c++) {
-				BOARD[r][c] = new Tile(this, numberTiles, specialTiles);
+				BOARD[r][c] = new Tile(this);
 				BOARD_PANEL.add(BOARD[r][c]);
 			}
 		}
@@ -119,38 +180,37 @@ public class Canvas extends JPanel {
 			}
 		}
 
-		Image[] digits = getImageSet(tileset, NumberDisplay.MINUS_INDEX, TS_DIGITS_Y,
+		// Initialize the other components
-				NumberDisplay.DIGIT_WIDTH, NumberDisplay.DIGIT_HEIGHT);
+		FLAGS_DISPLAY = new NumberDisplay();
-		Image numberDisplayBackdrop = tileset.getSubimage(TS_DIGIT_BACKDROP_X, TS_MISC_Y,
+		TIMER_DISPLAY = new NumberDisplay();
-				NumberDisplay.BACKDROP_WIDTH, NumberDisplay.BACKDROP_HEIGHT);
+		FACE = new Face(this);
 
-		FLAGS_DISPLAY = new NumberDisplay(numberDisplayBackdrop, digits);
+		// Now that the components are all initialized, set all of their images
-		TIMER_DISPLAY = new NumberDisplay(numberDisplayBackdrop, digits);
+		setImages();
-		FACE = new Face(this, getImageSet(tileset, Face.PRESSED_INDEX, TS_FACES_Y, Face.SIZE, Face.SIZE));
 
+		// Shift+LMB chords, so we need some way of determining if the shift key
+		// is being held.
 		SHIFT_KEY_LISTENER = new KeyAdapter() {
-			// Shift+LMB chords, so we need some way of determining if the shift
-			// key is being held.
 			@Override
 			public void keyPressed(KeyEvent e) {
-				if (e.getKeyCode() == KeyEvent.VK_SHIFT) {
+				updateShift(e, true);
-					holdingShift = true;
-					updateCurrentTile();
-				}
 			}
 
 			@Override
 			public void keyReleased(KeyEvent e) {
-				if (e.getKeyCode() == KeyEvent.VK_SHIFT) {
+				updateShift(e, false);
-					holdingShift = false;
-					updateCurrentTile();
-				}
 			}
 
-			private void updateCurrentTile() {
+			// Helper method to update holdingShift to the new value if shift
+			// was pressed, and additionally update the pressed state of the
+			// current tile if that exists
+			private void updateShift(KeyEvent e, boolean newValue) {
+				if (e.getKeyCode() == KeyEvent.VK_SHIFT) {
+					holdingShift = newValue;
 					if (currentTile != null)
 						currentTile.updatePressedState();
 				}
+			}
 		};
 
 		// 1 second delay
@@ -163,12 +223,13 @@ public class Canvas extends JPanel {
 					return;
 				}
 
+				// Play the tick sound and increment the timer number
 				Sound.TICK.play();
 				TIMER_DISPLAY.setNum(++time);
 			}
 		});
 
-		// Null layout, for manual placement of all game components
+		// Null layout, for fine-tuned placement of all game components
 		setLayout(null);
 		Insets insets = getInsets();
 		placeComponent(BOARD_PANEL, BORDER_WIDTH, 2 * BORDER_HEIGHT + TOP_BOX_HEIGHT, insets);
@@ -182,11 +243,19 @@ public class Canvas extends JPanel {
 		init();
 	}
 
+	// Refresh the skin and repaint
+	public void newSkin() {
+		setImages();
+		repaint();
+	}
+
+	// Stop everything that might be running
 	public void stop() {
 		TIMER.stop();
 		removeKeyListener(SHIFT_KEY_LISTENER);
 	}
 
+	// Restart the game
 	public void restart() {
 		if (!gameStarted)
 			return;
@@ -218,20 +287,22 @@ public class Canvas extends JPanel {
 		TIMER.start();
 	}
 
+	// After every tile revealed, check for game ending
 	public void postRevealCheck() {
-		if (gameLost) {
+		if (gameLost) { // Loss
 			Sound.EXPLODE.play();
-			stopGame();
+			endGame();
 			FACE.setFace(Face.DEAD_INDEX);
-		} else if (numTilesLeft == 0) {
+		} else if (numTilesLeft == 0) { // Win
 			Sound.WIN.play();
 			// Automatically flag all remaining tiles on win
 			FLAGS_DISPLAY.setNum(0);
-			stopGame();
+			endGame();
 			FACE.setFace(Face.COOL_INDEX);
 		}
 	}
 
+	// Modify the flag counter
 	public void modifyFlagCount(boolean addedFlag) {
 		if (addedFlag)
 			numFlagsLeft--;
@@ -240,18 +311,25 @@ public class Canvas extends JPanel {
 		FLAGS_DISPLAY.setNum(numFlagsLeft);
 	}
 
+	// Called by tile every single time one is revealed
 	public void revealedSingleTile() {
 		numTilesLeft--;
 	}
 
+	// Called by tile if it is a mine when revealed
 	public void setLoseFlag() {
 		gameLost = true;
 	}
 
+	// Every tile has a MouseListener, but the canvas must be aware of the mouse
+	// button state because other tiles that weren't the one that was initially
+	// clicked also need to know the mouse button state, so Canvas has a setter
+	// for it
 	public void setLeftMouseDown(boolean b) {
 		if (gameEnded)
 			return;
 
+		// Face gets nervous when clicking
 		leftMouseDown = b;
 		if (leftMouseDown)
 			FACE.setFace(Face.SHOCKED_INDEX);
@@ -259,7 +337,9 @@ public class Canvas extends JPanel {
 			FACE.setFace(Face.HAPPY_INDEX);
 	}
 
+	// Ditto
 	public void setRightMouseDown(boolean b) {
+		if (!gameEnded)
 			rightMouseDown = b;
 	}
 
@@ -267,10 +347,16 @@ public class Canvas extends JPanel {
 		return leftMouseDown;
 	}
 
+	// Chording can be done with either the right mouse button or the shift key
 	public boolean isChording() {
 		return holdingShift || rightMouseDown;
 	}
 
+	// Tiles need to know what tile the mouse is currently over because the
+	// MouseReleased event is triggered on the tile that the mouse was pressed
+	// down on, not the one it was released on, but the tile that it was
+	// released on is the one that actually gets revealed, which we would
+	// otherwise have no way of knowing
 	public Tile getCurrentTile() {
 		return currentTile;
 	}
@@ -283,14 +369,18 @@ public class Canvas extends JPanel {
 		return gameLost;
 	}
 
-	private static Image getTileFromSet(BufferedImage tileset, int n, int y) {
+	// Get the nth tile from the tileset, with the initial y-value of y
+	private Image getTileFromSet(BufferedImage tileset, int n, int y) {
 		return tileset.getSubimage(Tile.SIZE * n, y, Tile.SIZE, Tile.SIZE);
 	}
 
-	private Image[] getImageSet(BufferedImage tileset, int lastIndex, int y, int width, int height) {
+	// For the other images, which have a 1-pixel gap between them: return an
-		Image[] img = new Image[lastIndex + 1];
+	// array of images by slicing subimages of the given size from the image,
+	// with a 1-pixel gap between them
+	private Image[] getImageSet(BufferedImage tileset, int n, int y, int width, int height) {
+		Image[] img = new Image[n];
 		int x = 0;
-		for (int i = 0; i <= lastIndex; i++) {
+		for (int i = 0; i < n; i++) {
 			img[i] = tileset.getSubimage(x, y, width, height);
 			x += width + 1;
 		}
@@ -367,7 +457,8 @@ public class Canvas extends JPanel {
 		c.setSize(c.getPreferredSize());
 	}
 
-	private void stopGame() {
+	// Stop the moving parts after a win or a loss
+	private void endGame() {
 		TIMER.stop();
 		gameEnded = true;
 		for (Tile[] row : BOARD)
@@ -377,8 +468,10 @@ public class Canvas extends JPanel {
 
 	// Override the paintComponent method in order to add the background image
 	@Override
-	public void paintComponent(Graphics g) {
+	public void paintComponent(Graphics gr) {
-		super.paintComponent(g);
+		super.paintComponent(gr);
-		g.drawImage(BACKGROUND_IMAGE, 0, 0, this);
+		Graphics2D g = (Graphics2D) gr;
+
+		g.drawImage(backgroundImage, 0, 0, this);
 	}
 }

CustomTextField.java

@@ -1,7 +1,9 @@
 import java.awt.event.*;
 import javax.swing.*;
 
+// Custom text field for use when creating new custom games
 public class CustomTextField extends JTextField {
+	// The number of columns of characters to have
 	private static final int COLS = 4;
 
 	private final int MIN_VALUE;

Difficulty.java

@@ -1,7 +1,7 @@
 import java.awt.*;
-import java.awt.event.*;
 import javax.swing.*;
 
+// Enum with the difficuulty options
 public enum Difficulty {
 	BEGINNER     (9,  9,  10),
 	INTERMEDIATE (16, 16, 40),
@@ -20,6 +20,8 @@ public enum Difficulty {
 	// it's possible to hit the number display cap
 	private static final int MAX_MINES = 999;
 
+	// Use nonfinal ints with getter methods because custom needs to be able to
+	// change its stats
 	private int rows;
 	private int cols;
 	private int mines;
@@ -49,6 +51,8 @@ public enum Difficulty {
 		return mines;
 	}
 
+	// Show a popup window to select attributes of the custom game, return
+	// whether or not it succeeded
 	public static boolean setCustom(JFrame frame) {
 		Difficulty current = Options.getDifficulty();
 
@@ -71,6 +75,7 @@ public enum Difficulty {
 			}
 		}
 
+		// Initialize the text fields
 		CustomTextField rowsField = new RowsColsField(current.rows, MIN_SIZE, MAX_ROWS);
 		CustomTextField colsField = new RowsColsField(current.cols, MIN_SIZE, MAX_COLS);
 		// Override CustomTextField in order to make it dynamically determine
@@ -89,18 +94,21 @@ public enum Difficulty {
 		};
 
 		// Because Java is lame and doesn't have builtin tuples we make do with
-		// casting an JComponent[][]
+		// a JComponent[][] to store the structure of the input window
 		JComponent[][] items = {
 			{ new JLabel("Height:"), rowsField },
 			{ new JLabel("Width:"),  colsField },
 			{ new JLabel("Mines:"),  minesField },
 		};
 
-		int option = JOptionPane.showConfirmDialog(frame, getMessagePanel(items, 6),
+		// Show the message window now and get the result
+		int option = JOptionPane.showConfirmDialog(frame, getMessagePanel(items),
 				"Custom Board", JOptionPane.OK_CANCEL_OPTION);
+		// If user didn't hit OK, bail out now
 		if (option != JOptionPane.OK_OPTION)
 			return false;
 
+		// Bail out if fields can't be parsed into integers
 		int rows, cols, mines;
 		try {
 			rows = Integer.parseInt(rowsField.getText());
@@ -110,8 +118,9 @@ public enum Difficulty {
 			return false;
 		}
 
-		// Clamp values to the allowed range, just in case something slipped
+		// Even though the text fields should technically only allow valid
-		// through the focusLost events
+		// inputs, we should clamp values to the allowed range, just in case
+		// something slipped through the focusLost events
 		rows = clampInt(rows, MIN_SIZE, MAX_ROWS);
 		cols = clampInt(cols, MIN_SIZE, MAX_COLS);
 		mines = clampInt(mines, MIN_MINES, getMaxMines(rows, cols));
@@ -120,24 +129,38 @@ public enum Difficulty {
 		if (current == CUSTOM && CUSTOM.rows == rows && CUSTOM.cols == cols && CUSTOM.mines == mines)
 			return false;
 
+		// Everything succeeded, so now actually set the new stats
 		CUSTOM.setStats(rows, cols, mines);
 
 		return true;
 	}
 
+	// Helper method to implement something that every language except Java
+	// already has builtin
 	public static int clampInt(int value, int minValue, int maxValue) {
 		return Math.max(Math.min(value, maxValue), minValue);
 	}
 
+	// The regular formula for maximum mines is the product of rows and columns
+	// minus one, but also cap it at 999
 	private static int getMaxMines(int rows, int cols) {
 		return Math.min((rows - 1) * (cols - 1), MAX_MINES);
 	}
 
-	private static JPanel getMessagePanel(JComponent[][] items, int padding) {
+	// Create a JPanel that has the items in a custom gridlike layout in which
+	// every row is as tall as the tallest element in that row and every column
+	// is as wide as the widest element in that column
+	private static JPanel getMessagePanel(JComponent[][] items) {
+		// The padding between the elements and from the walls
+		final int PADDING = 6;
+		// The number of columns
 		final int COLS = 2;
 
+		// Null layout because the only layout manager that can do what we we
+		// want is SpringLayout which the same complexity
 		JPanel messagePanel = new JPanel(null);
 
+		// Add the items to the panel, setting the label alignment along the way
 		for (JComponent[] row : items) {
 			JLabel label = (JLabel) row[0];
 			label.setLabelFor(row[1]);
@@ -146,32 +169,45 @@ public enum Difficulty {
 			messagePanel.add(row[1]);
 		}
 
-		int[] widths = new int[COLS];
+		// The maximum width of all the elements of each column
-		int[] heights = new int[items.length];
+		int[] maxWidths = new int[COLS];
+		// The maximum height of each elements of each row
+		int[] maxHeights = new int[items.length];
+		// The x-position of all elements of each column
 		int[] x = new int[COLS + 1];
+		// The y-position of all the elements of each row
 		int[] y = new int[items.length + 1];
+		// The last value of x and y hold the size of the panel itself
 
-		x[0] = padding;
+		// Set x and maxWidths
+		x[0] = PADDING;
 		for (int c = 0; c < COLS; c++) {
+			// Get the maximum width among items of this row
 			int maxWidth = Integer.MIN_VALUE;
 			for (int r = 0; r < items.length; r++)
 				maxWidth = Math.max(maxWidth, (int) items[r][c].getPreferredSize().getWidth());
-			widths[c] = maxWidth;
+			maxWidths[c] = maxWidth;
-			x[c + 1] = x[c] + maxWidth + padding;
+			// x-coordinate of the next item is the x-coordinate of this one
+			// plus this one's width plus padding
+			x[c + 1] = x[c] + maxWidth + PADDING;
 		}
 
+		// Set y and maxHeights the same way
+		y[0] = PADDING;
 		for (int r = 0; r < items.length; r++) {
 			int maxHeight = Integer.MIN_VALUE;
 			for (int c = 0; c < COLS; c++)
 				maxHeight = Math.max(maxHeight, (int) items[r][c].getPreferredSize().getHeight());
-			heights[r] = maxHeight;
+			maxHeights[r] = maxHeight;
-			y[r + 1] = y[r] + maxHeight + padding;
+			y[r + 1] = y[r] + maxHeight + PADDING;
 		}
 
+		// Actually put into use the values we just got
 		for (int r = 0; r < items.length; r++)
 			for (int c = 0; c < COLS; c++)
-				items[r][c].setBounds(x[c], y[r], widths[c], heights[r]);
+				items[r][c].setBounds(x[c], y[r], maxWidths[c], maxHeights[r]);
 
+		// Use the last values of x and y to set the size of the panel
 		messagePanel.setPreferredSize(new Dimension(x[COLS], y[items.length]));
 
 		return messagePanel;

Face.java

@@ -2,29 +2,42 @@ import java.awt.*;
 import java.awt.event.*;
 import javax.swing.*;
 
+// The face at the top of the game
 public class Face extends JComponent {
+	// The width and height
 	public static final int SIZE = 26;
+	// The indexes of each face in the array
 	public static final int HAPPY_INDEX = 0;
 	public static final int SHOCKED_INDEX = 1;
 	public static final int DEAD_INDEX = 2;
 	public static final int COOL_INDEX = 3;
 	public static final int PRESSED_INDEX = 4;
 
+	// The main game canvas to refer back to
 	private final Canvas GAME_CANVAS;
-	private final Image[] FACES;
+
+	private Image[] faces;
+	// The current face index
 	private int face;
+	// The last face index, before being pressed, in order to revert on unpress
 	private int unpressedFace;
+	// Whether the face is being pressed right now
 	private boolean pressed;
+	// Whether the mouse is over the face
 	private boolean mouseOver;
 
-	public Face(Canvas gameCanvas, Image[] faces) {
+	public Face(Canvas gameCanvas) {
-		FACES = faces;
 		GAME_CANVAS = gameCanvas;
 		face = HAPPY_INDEX;
 		pressed = false;
 		mouseOver = false;
 		setPreferredSize(new Dimension(SIZE, SIZE));
+		// We want to show the pressed sprite only if the mouse is down while
+		// the mouse is over the face, reverting back when it's no longer over
+		// the face but coming back as soon as the mouse comes back
 		addMouseListener(new MouseAdapter() {
+			// The only way to initiate a pressed face state is when the mouse
+			// is over it and is pressed down
 			@Override
 			public void mousePressed(MouseEvent e) {
 				pressed = true;
@@ -32,6 +45,10 @@ public class Face extends JComponent {
 				setFace(PRESSED_INDEX);
 			}
 
+			// If the face recieves a mouseReleased event while the mouse is
+			// over it, that means that it was a completed click, so restart the
+			// game on the canvas, also resetting back to the happy face that
+			// should be shown at the start of every game
 			@Override
 			public void mouseReleased(MouseEvent e) {
 				pressed = false;
@@ -41,6 +58,8 @@ public class Face extends JComponent {
 				}
 			}
 
+			// If it was previously being pressed, reshow the pressed sprite as
+			// soon as mouse enters
 			@Override
 			public void mouseEntered(MouseEvent e) {
 				mouseOver = true;
@@ -48,6 +67,8 @@ public class Face extends JComponent {
 					setFace(PRESSED_INDEX);
 			}
 
+			// Temporarily show the unpressed face, but keep the pressed boolean
+			// true in case the mouse reenters
 			@Override
 			public void mouseExited(MouseEvent e) {
 				mouseOver = false;
@@ -57,6 +78,10 @@ public class Face extends JComponent {
 		});
 	}
 
+	public void setImages(Image[] faces) {
+		this.faces = faces;
+	}
+
 	public void setFace(int face) {
 		this.face = face;
 		repaint();
@@ -67,6 +92,6 @@ public class Face extends JComponent {
 		super.paintComponent(gr);
 		Graphics2D g = (Graphics2D) gr;
 
-		g.drawImage(FACES[face], 0, 0, this);
+		g.drawImage(faces[face], 0, 0, this);
 	}
 }

Main.java

@@ -7,21 +7,21 @@ import javax.swing.*;
 import javax.swing.event.*;
 
 public class Main {
-	public static final String DEFAULT_SKIN = "winxpskin.bmp";
+	// HTML filenames to be shown in the Help menu
-	public static final String SKINS_DIR = "Skins/";
 	public static final String HELP_FILE = "help.html";
 	public static final String ABOUT_FILE = "about.html";
 
-	private static final String[] VALID_EXTENSIONS = {".bmp", ".png", ".webp"};
+	// Valid file extensions for skins to be listed in the menu
+	private static final String[] VALID_SKINS_EXTENSIONS = {".bmp", ".png", ".webp"};
 
+	// Game frame
 	private static final JFrame FRAME = new JFrame("Minesweeper");
 
+	// The current game Canvas
 	private static Canvas canvas;
-	private static String skin;
 
+	// Entry point: simply create the frame, set the canvas, and show the frame
 	public static void main(String[] args) {
-		skin = DEFAULT_SKIN;
-
 		FRAME.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
 		FRAME.setResizable(false);
 		FRAME.setJMenuBar(getMenuBar());
@@ -30,6 +30,7 @@ public class Main {
 		FRAME.setVisible(true);
 	}
 
+	// Create the menu bar of the frame
 	private static JMenuBar getMenuBar() {
 		// Button group for the difficulty buttons
 		ButtonGroup difficultyButtons = new ButtonGroup();
@@ -46,12 +47,13 @@ public class Main {
 		difficultyButtons.add(expertItem);
 		difficultyButtons.add(customItem);
 
+		// ActionListener for every button except the skins ones
 		ActionListener listener = new ActionListener() {
 			// Keep track of the previously selected difficulty button in case a
-			// Custom press is canceled so we can revert back to whatever it was
+			// Custom press is canceled so we can revert the button selection
-			// before
 			private ButtonModel lastDifficultyButton = difficultyButtons.getSelection();
 
+			// Parse the action command and perform the corresponding action
 			@Override
 			public void actionPerformed(ActionEvent e) {
 				switch (e.getActionCommand()) {
@@ -71,6 +73,8 @@ public class Main {
 					lastDifficultyButton = expertItem.getModel();
 					break;
 				case "custom":
+					// If canceled, set the currently selected button to
+					// whatever it was before
 					if (Difficulty.setCustom(FRAME)) {
 						setDifficulty(Difficulty.CUSTOM);
 						lastDifficultyButton = customItem.getModel();
@@ -102,6 +106,7 @@ public class Main {
 
 		JMenuBar menuBar = new JMenuBar();
 
+		// Create the Game item in the menu bar
 		JMenu gameMenu = new JMenu("Game");
 		gameMenu.setMnemonic(KeyEvent.VK_G);
 		JMenuItem newGameItem = new JMenuItem("New game");
@@ -123,6 +128,7 @@ public class Main {
 		addMenuItem("Exit", gameMenu, KeyEvent.VK_X, "exit", listener);
 		menuBar.add(gameMenu);
 
+		// Create the Help item in the menu bar
 		JMenu helpMenu = new JMenu("Help");
 		helpMenu.setMnemonic(KeyEvent.VK_H);
 		JMenuItem helpItem = new JMenuItem("Help");
@@ -132,28 +138,32 @@ public class Main {
 		addMenuItem("About", helpMenu, KeyEvent.VK_A, "about", listener);
 		menuBar.add(helpMenu);
 
+		// Create the Skins item in the menu bar (this one is special)
 		JMenu skinsMenu = new JMenu("Skins");
 		skinsMenu.setMnemonic(KeyEvent.VK_S);
 		// The Skins menu should dynamically generate a menu of all image files
-		// in the skins directory when clicked in order to select one
+		// in the Skins directory when clicked in order to select one
 		skinsMenu.addMenuListener(new MenuListener() {
+			// Skins have a separate ActionListener from the other buttons so we
+			// can simply set the action command to the name of the new skin
+			// without worrying about collisions or messiness
 			private static ActionListener skinListener = new ActionListener() {
 				@Override
 				public void actionPerformed(ActionEvent e) {
 					// Set the skin to the new one if it isn't already that
 					String newSkin = e.getActionCommand();
-					if (newSkin.equals(skin))
+					if (newSkin.equals(Options.getSkinName()))
 						return;
 
-					skin = newSkin;
+					Options.setSkinName(newSkin);
-					replaceCanvas();
+					canvas.newSkin();
 				}
 			};
 
 			@Override
 			public void menuSelected(MenuEvent e) {
 				// Get a stream of all files in the skins directory
-				try (Stream<Path> dirStream = Files.list(Paths.get(SKINS_DIR))) {
+				try (Stream<Path> dirStream = Files.list(Paths.get(Options.SKINS_DIR))) {
 					dirStream
 							// Filter for only regular files
 							.filter(Files::isRegularFile)
@@ -162,19 +172,17 @@ public class Main {
 							.map(Path::toString)
 							// Only allow a filename if it ends with one of the
 							// valid extensions
-							.filter(name -> Arrays.stream(VALID_EXTENSIONS)
+							.filter(name -> Arrays.stream(VALID_SKINS_EXTENSIONS)
-									// Use regionMatches to effectively
+									.anyMatch(ext -> name.toLowerCase().endsWith(ext)))
-									// case-insensitively endsWith()
+							// Because Files.list() does not guarantee an order,
-									.anyMatch(ext -> name.regionMatches(true,
+							// and alphabetically sorted files look objectively
-											name.length() - ext.length(), ext, 0, ext.length())))
+							// nicer in directory listings
-							// Because Files.list does not guarantee an order, and
-							// alphabetical files look objectively nicer in lists
 							.sorted()
 							// Create a radio button menu item for each one,
 							// remembering to have it pre-selected if it's already
 							// the current skin
-							.forEach(name -> addMenuItem(new JRadioButtonMenuItem(name, name.equals(skin)),
+							.forEach(name -> addMenuItem(new JRadioButtonMenuItem(name,
-									skinsMenu, name, skinListener));
+									name.equals(Options.getSkinName())), skinsMenu, name, skinListener));
 				} catch (IOException ignore) {
 					// It's fine to leave it blank if we can't get results
 				}
@@ -196,27 +204,8 @@ public class Main {
 		return menuBar;
 	}
 
-	private static void messageHtmlFile(String file, String failText, String title, int messageType) {
+	// Helper items for adding menu items without needing a million copy-pasted
-		String text;
+	// lines
-		try {
-			// For some reason, JLabels just stop parsing HTML after they hit a
-			// newline, so swap the newlines out with spaces
-			text = Files.readString(Paths.get(file)).replace('\n', ' ');
-		} catch (IOException e) {
-			text = failText;
-		}
-		JOptionPane.showMessageDialog(FRAME, text, title, messageType);
-	}
-
-	private static void setDifficulty(Difficulty newDifficulty) {
-		// Reject switching difficulty to the already-existing one unless Custom
-		if (Options.getDifficulty() == newDifficulty && newDifficulty != Difficulty.CUSTOM)
-			return;
-
-		Options.setDifficulty(newDifficulty);
-		replaceCanvas();
-	}
-
 	private static void addMenuItem(String menuTitle, JMenu menu, int mnemonic, String actionCommand,
 			ActionListener listener) {
 		addMenuItem(new JMenuItem(menuTitle), menu, mnemonic, actionCommand, listener);
@@ -235,17 +224,40 @@ public class Main {
 		menu.add(menuItem);
 	}
 
-	private static void replaceCanvas() {
+	// Read the given HTML file and message it with JOptionPane, using failText
+	// instead in case of failure
+	private static void messageHtmlFile(String file, String failText, String title, int messageType) {
+		String text;
+		try {
+			// For some reason, JLabels just stop parsing HTML after they hit a
+			// newline, so swap the newlines out with spaces
+			text = Files.readString(Paths.get(file)).replace('\n', ' ');
+		} catch (IOException e) {
+			text = failText;
+		}
+		JOptionPane.showMessageDialog(FRAME, text, title, messageType);
+	}
+
+	// Maybe change the difficulty to the new difficulty
+	private static void setDifficulty(Difficulty newDifficulty) {
+		// Reject switching difficulty to the already-existing one unless
+		// Custom, because that will still be different
+		if (Options.getDifficulty() == newDifficulty && newDifficulty != Difficulty.CUSTOM)
+			return;
+
+		Options.setDifficulty(newDifficulty);
+
+		// Replace the canvas with a new one, which will get the new difficulty
 		canvas.stop();
 		canvas.removeAll();
 		FRAME.remove(canvas);
-
 		setCanvas();
 		canvas.requestFocusInWindow();
-}
+	}
 
+	// Create a new canvas and put it in the frame
 	private static void setCanvas() {
-		canvas = new Canvas(new File(SKINS_DIR, skin));
+		canvas = new Canvas();
 		FRAME.add(canvas);
 		FRAME.pack();
 	}

NumberDisplay.java

@@ -1,28 +1,37 @@
 import java.awt.*;
 import javax.swing.*;
 
+// The number displays in the game
 public class NumberDisplay extends JComponent {
+	// The dimensions of each individual digit
 	public static final int DIGIT_WIDTH = 11;
 	public static final int DIGIT_HEIGHT = 21;
+	// The dimensions of the big box
 	public static final int BACKDROP_WIDTH = 41;
 	public static final int BACKDROP_HEIGHT = 25;
+	// The index of the minus sign
 	public static final int MINUS_INDEX = 10;
 
+	// The x-positions of each digit: units -> tens -> hundreds
 	private static final int[] DIGIT_X = {28, 15, 2};
+	// The y-position of each digit
 	private static final int DIGIT_Y = 2;
 
-	public final Image BACKDROP;
+	public Image backdrop;
-	public final Image[] DIGITS;
+	public Image[] digits;
 
 	private int num;
 	private boolean negative;
 
-	public NumberDisplay(Image backdrop, Image[] digits) {
+	public NumberDisplay() {
-		BACKDROP = backdrop;
-		DIGITS = digits;
 		setPreferredSize(new Dimension(BACKDROP_WIDTH, BACKDROP_HEIGHT));
 	}
 
+	public void setImages(Image[] digits, Image backdrop) {
+		this.digits = digits;
+		this.backdrop = backdrop;
+	}
+
 	public void setNum(int num) {
 		setClamped(num);
 		repaint();
@@ -44,17 +53,20 @@ public class NumberDisplay extends JComponent {
 		super.paintComponent(gr);
 		Graphics2D g = (Graphics2D) gr;
 
-		g.drawImage(BACKDROP, 0, 0, this);
+		g.drawImage(backdrop, 0, 0, this);
-		// Preserve the original num for divison, in case we repaint twice
+		// Preserve the original num for in-place divison, because we don't want
-		// without updating the number
+		// non-graphical side effects in paintComponent
 		int num = this.num;
 		for (int i = 0; i < 3; i++) {
 			int digitsIndex;
+			// Get the index of the proper digit for this position, drawing the
+			// minus sign in the hundreds digit if necessary
 			if (negative && i == 2)
 				digitsIndex = MINUS_INDEX;
 			else
 				digitsIndex = num % 10;
-			g.drawImage(DIGITS[digitsIndex], DIGIT_X[i], DIGIT_Y, this);
+			g.drawImage(digits[digitsIndex], DIGIT_X[i], DIGIT_Y, this);
+			// Next digit
 			num /= 10;
 		}
 	}

Options.java

@@ -1,11 +1,16 @@
 // Public class that stores all the global static options
 public class Options {
+	// Directory with all the skins files
+	public static final String SKINS_DIR = "Skins/";
+
 	// Whether or not sound is enabled
 	private static boolean sound = false;
 	// Whether or not to force starting at 0
 	private static boolean protectedStart = false;
 	// The difficulty
 	private static Difficulty difficulty = Difficulty.INTERMEDIATE;
+	// The skin
+	private static String skinName = "winxpskin.bmp";
 
 	public static boolean hasSound() {
 		return sound;
@@ -31,6 +36,14 @@ public class Options {
 		Options.difficulty = difficulty;
 	}
 
+	public static String getSkinName() {
+		return skinName;
+	}
+
+	public static void setSkinName(String skinName) {
+		Options.skinName = skinName;
+	}
+
 	// No constructing >:(
 	private Options() {
 	}

Tile.java

@@ -1,10 +1,13 @@
 import java.awt.*;
-import java.util.HashSet;
+import java.util.ArrayList;
 import java.awt.event.*;
 import javax.swing.*;
 
+// A single tile on the game board
 public class Tile extends JComponent {
+	// The size of the tile
 	public static final int SIZE = 16;
+	// The indexes of each special image in the special tiles array
 	public static final int REGULAR_INDEX = 0;
 	public static final int PRESSED_INDEX = 1;
 	public static final int MINE_INDEX = 2;
@@ -12,27 +15,35 @@ public class Tile extends JComponent {
 	public static final int NOT_MINE_INDEX = 4;
 	public static final int EXPLODED_MINE_INDEX = 5;
 
+	// The main game canvas to refer back to
 	private final Canvas GAME_CANVAS;
-	private final Image[] NUMBER_TILES;
-	private final Image[] SPECIAL_TILES;
 
 	// Store the mouse listener for convenient removal once the game ends
 	private final MouseListener TILE_MOUSE_LISTENER;
 
-	// A set of all the Tiles that are adjacent to this one, for calculating
+	// A collection of all the Tiles that are adjacent to this one, for
-	// numbers and autorevealing zeros and chording
+	// calculating numbers and autorevealing zeros and chording
-	private final HashSet<Tile> ADJACENT_TILES;
+	private final ArrayList<Tile> ADJACENT_TILES;
+
+	// The numbered tiles 0-9
+	private Image[] numberTiles;
+	// All the other possible tiles (see *_INDEX above)
+	private Image[] specialTiles;
 
 	// Whether or not the tile is a mine
 	private boolean mine;
 	// The number of mines adjacent to the current one
 	private int num;
-	// Whether or not this mine has been revealed already
+	// Tile state
 	private boolean revealed;
-	// Whether or not this mine has been flagged
 	private boolean flagged;
+	// Whether this tile should show the pressed sprite (the mouse is down and
+	// this tile is either the currently moused-over tile or is adjacent to it
+	// while chording)
 	private boolean pressed;
+	// Whether the mouse is over the tile
 	private boolean mouseOver;
+	// Whether the game has ended
 	private boolean gameEnded;
 
 	private void init() {
@@ -46,12 +57,13 @@ public class Tile extends JComponent {
 		addMouseListener(TILE_MOUSE_LISTENER);
 	}
 
-	public Tile(Canvas gameCanvas, Image[] numberTiles, Image[] specialTiles) {
+	public Tile(Canvas gameCanvas) {
 		GAME_CANVAS = gameCanvas;
-		NUMBER_TILES = numberTiles;
+		ADJACENT_TILES = new ArrayList<Tile>();
-		SPECIAL_TILES = specialTiles;
-		ADJACENT_TILES = new HashSet<Tile>();
 
+		// Every tile has its own mouse listener in order for the game to always
+		// know when the mouse moves over from one tile to the other in order to
+		// update the pressed state of the tiles
 		TILE_MOUSE_LISTENER = new MouseAdapter() {
 			@Override
 			public void mousePressed(MouseEvent e) {
@@ -122,11 +134,17 @@ public class Tile extends JComponent {
 		init();
 	}
 
+	public void setImages(Image[] numberTiles, Image[] specialTiles) {
+		this.numberTiles = numberTiles;
+		this.specialTiles = specialTiles;
+	}
+
 	public void restart() {
 		removeMouseListener(TILE_MOUSE_LISTENER);
 		init();
 	}
 
+	// Update ADJACENT_TILES at the start of the game
 	public void addAdjacentTile(Tile tile) {
 		ADJACENT_TILES.add(tile);
 	}
@@ -145,6 +163,7 @@ public class Tile extends JComponent {
 		return true;
 	}
 
+	// Flip gameEnded and repaint one last time
 	public void gameEnd() {
 		removeMouseListener(TILE_MOUSE_LISTENER);
 		gameEnded = true;
@@ -153,6 +172,7 @@ public class Tile extends JComponent {
 			repaint();
 	}
 
+	// Update the pressed state, whenever something pressing-related happens
 	public void updatePressedState() {
 		if (pressed != (GAME_CANVAS.isLeftMouseDown() && mouseOver)) {
 			pressed = !pressed;
@@ -167,6 +187,7 @@ public class Tile extends JComponent {
 		}
 	}
 
+	// Flag on unrevealed tiles on right click
 	private void rightClickAction() {
 		if (revealed)
 			return;
@@ -176,11 +197,13 @@ public class Tile extends JComponent {
 		repaint();
 	}
 
+	// Chord or reveal tiles on left click
 	private void leftClickAction() {
 		if (GAME_CANVAS.isChording()) {
 			if (!revealed)
 				return;
 
+			// Check that chording should happen
 			int adjacentFlags = 0;
 			for (Tile tile : ADJACENT_TILES)
 				if (tile.flagged)
@@ -188,12 +211,14 @@ public class Tile extends JComponent {
 			if (adjacentFlags != num)
 				return;
 
+			// Chord
 			for (Tile tile : ADJACENT_TILES)
 				if (!tile.flagged)
 					tile.reveal();
 		} else {
 			if (flagged || revealed)
 				return;
+
 			// Ensure that mines are placed before revealing anything
 			GAME_CANVAS.tryStartGame(this);
 			reveal();
@@ -201,6 +226,7 @@ public class Tile extends JComponent {
 		GAME_CANVAS.postRevealCheck();
 	}
 
+	// Reveal the current tile
 	private void reveal() {
 		if (revealed)
 			return;
@@ -210,37 +236,39 @@ public class Tile extends JComponent {
 
 		if (mine) {
 			GAME_CANVAS.setLoseFlag();
-		} else {
+			return;
+		}
+
 		GAME_CANVAS.revealedSingleTile();
+		// Recursively reveal all adjacent tiles if this one is 0
 		if (num == 0)
 			for (Tile tile : ADJACENT_TILES)
 				if (!tile.flagged)
 					tile.reveal();
 	}
-	}
 
 	// Determine what image should be drawn at this tile
 	private Image getImage() {
 		if (gameEnded && mine) {
 			// Automatically flag mines at wins, losses keep correct flags
 			if (!GAME_CANVAS.isGameLost() || flagged)
-				return SPECIAL_TILES[FLAGGED_INDEX];
+				return specialTiles[FLAGGED_INDEX];
 			if (revealed)
-				return SPECIAL_TILES[EXPLODED_MINE_INDEX];
+				return specialTiles[EXPLODED_MINE_INDEX];
-			return SPECIAL_TILES[MINE_INDEX];
+			return specialTiles[MINE_INDEX];
 		}
 		if (revealed)
-			return NUMBER_TILES[num];
+			return numberTiles[num];
 		if (flagged) {
 			// Correctly flagged mines would have been caught earlier
 			if (gameEnded)
-				return SPECIAL_TILES[NOT_MINE_INDEX];
+				return specialTiles[NOT_MINE_INDEX];
-			return SPECIAL_TILES[FLAGGED_INDEX];
+			return specialTiles[FLAGGED_INDEX];
 		}
 		// Tiles are only interactable if the game is ongoing
 		if (pressed && !gameEnded)
-			return SPECIAL_TILES[PRESSED_INDEX];
+			return specialTiles[PRESSED_INDEX];
-		return SPECIAL_TILES[REGULAR_INDEX];
+		return specialTiles[REGULAR_INDEX];
 	}
 
 	@Override