import java.awt.event.*;
import java.io.*;
import java.nio.file.*;
import java.util.stream.Stream;
import java.util.Arrays;
import javax.swing.*;
import javax.swing.event.*;

public class Main {
	private static enum Difficulty {
		BEGINNER     (9,  9,  10),
		INTERMEDIATE (16, 16, 40),
		EXPERT       (16, 30, 99);

		public final int ROWS;
		public final int COLS;
		public final int MINES;

		Difficulty(int rows, int cols, int mines) {
			this.ROWS = rows;
			this.COLS = cols;
			this.MINES = mines;
		}
	}

	public static final String DEFAULT_SKIN = "winxpskin.bmp";
	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"};

	private static final JFrame FRAME = new JFrame("Minesweeper");

	private static Canvas canvas;
	private static Difficulty difficulty;
	private static String skin;
	private static boolean protectedStart;
	private static boolean sound;

	public static void main(String[] args) {
		difficulty = Difficulty.INTERMEDIATE;
		skin = DEFAULT_SKIN;
		protectedStart = false;
		sound = false;
		setCanvas();

		FRAME.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		FRAME.setResizable(false);
		FRAME.setJMenuBar(getMenuBar());
		FRAME.add(canvas);
		FRAME.pack();
		FRAME.setVisible(true);
	}

	public static boolean isProtectedStart() {
		return protectedStart;
	}

	public static boolean hasSound() {
		return sound;
	}

	private static JMenuBar getMenuBar() {
		ActionListener listener = new ActionListener() {
			@Override
			public void actionPerformed(ActionEvent e) {
				switch (e.getActionCommand()) {
				case "new":
					canvas.restart();
					break;
				case "beginner":
					setDifficulty(Difficulty.BEGINNER);
					break;
				case "intermediate":
					setDifficulty(Difficulty.INTERMEDIATE);
					break;
				case "expert":
					setDifficulty(Difficulty.EXPERT);
					break;
				case "custom":
					setDifficulty(null);
					break;
				case "protectedstart":
					protectedStart = !protectedStart;
					break;
				case "sound":
					sound = !sound;
					Sound.initSounds();
					break;
				case "exit":
					FRAME.dispatchEvent(new WindowEvent(FRAME, WindowEvent.WINDOW_CLOSING));
					break;
				case "help":
					messageHtmlFile(HELP_FILE, "Failed to read help file, just google it lol.",
							"Minesweeper Help", JOptionPane.QUESTION_MESSAGE);
					break;
				case "about":
					messageHtmlFile(ABOUT_FILE, "I love microsoft!!",
							"Minesweeper About", JOptionPane.INFORMATION_MESSAGE);
					break;
				}
			}
		};

		JMenuBar menuBar = new JMenuBar();

		JMenu gameMenu = new JMenu("Game");
		gameMenu.setMnemonic(KeyEvent.VK_G);
		JMenuItem newGameItem = new JMenuItem("New game");
		newGameItem.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_F2, 0));
		addMenuItem(newGameItem, gameMenu, KeyEvent.VK_N, "new", listener);
		gameMenu.addSeparator();
		ButtonGroup difficultyButtons = new ButtonGroup();
		JRadioButtonMenuItem beginnerItem = new JRadioButtonMenuItem("Beginner");
		JRadioButtonMenuItem intermediateItem = new JRadioButtonMenuItem("Intermediate", true);
		JRadioButtonMenuItem expertItem = new JRadioButtonMenuItem("Advanced");
		JRadioButtonMenuItem customItem = new JRadioButtonMenuItem("Custom...");
		difficultyButtons.add(beginnerItem);
		difficultyButtons.add(intermediateItem);
		difficultyButtons.add(expertItem);
		difficultyButtons.add(customItem);
		addMenuItem(beginnerItem, gameMenu, KeyEvent.VK_B, "beginner", listener);
		addMenuItem(intermediateItem, gameMenu, KeyEvent.VK_I, "intermediate", listener);
		addMenuItem(expertItem, gameMenu, KeyEvent.VK_E, "expert", listener);
		addMenuItem(customItem, gameMenu, KeyEvent.VK_C, "custom", listener);
		gameMenu.addSeparator();
		JCheckBoxMenuItem protectedStartItem = new JCheckBoxMenuItem("Protected Start", protectedStart);
		protectedStartItem.setToolTipText("Guarantees the starting tile has no mines next to it");
		addMenuItem(protectedStartItem, gameMenu, KeyEvent.VK_P, "protectedstart", listener);
		JCheckBoxMenuItem soundItem = new JCheckBoxMenuItem("Sound", sound);
		addMenuItem(soundItem, gameMenu, KeyEvent.VK_O, "sound", listener);
		gameMenu.addSeparator();
		addMenuItem("Exit", gameMenu, KeyEvent.VK_X, "exit", listener);
		menuBar.add(gameMenu);

		JMenu helpMenu = new JMenu("Help");
		helpMenu.setMnemonic(KeyEvent.VK_H);
		JMenuItem helpItem = new JMenuItem("Help");
		helpItem.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_F1, 0));
		addMenuItem(helpItem, helpMenu, KeyEvent.VK_H, "help", listener);
		helpMenu.addSeparator();
		addMenuItem("About", helpMenu, KeyEvent.VK_A, "about", listener);
		menuBar.add(helpMenu);

		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
		skinsMenu.addMenuListener(new MenuListener() {
			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))
						return;

					skin = newSkin;
					replaceCanvas();
				}
			};

			@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))) {
					dirStream
						// Filter for only regular files
						.filter(file -> Files.isRegularFile(file))
						// Cut off the directory name from the resulting string
						.map(Path::getFileName)
						.map(Path::toString)
						// Only allow a filename if it ends with one of the
						// valid extensions
						.filter(name -> Arrays.stream(VALID_EXTENSIONS)
								// Use regionMatches to effectively
								// case-insensitively endsWith()
								.anyMatch(ext -> name.regionMatches(true,
										name.length() - ext.length(), ext, 0, ext.length())))
						// 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)),
										skinsMenu, name, skinListener));
				} catch (IOException ignore) {
					// It's fine to leave it blank if we can't get results
				}
			}

			@Override
			public void menuDeselected(MenuEvent e) {
				// Remove skins when we're done so they don't duplicate every
				// time we open the menu
				skinsMenu.removeAll();
			}

			@Override
			public void menuCanceled(MenuEvent e) {
			}
		});
		menuBar.add(skinsMenu);

		return menuBar;
	}

	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);
	}

	private static void setDifficulty(Difficulty newDifficulty) {
		if (newDifficulty == null);
		else if (difficulty == newDifficulty)
			return;

		difficulty = newDifficulty;
		replaceCanvas();
	}

	private static void addMenuItem(String menuTitle, JMenu menu, int mnemonic, String actionCommand,
			ActionListener listener) {
		addMenuItem(new JMenuItem(menuTitle), menu, mnemonic, actionCommand, listener);
	}

	private static void addMenuItem(JMenuItem menuItem, JMenu menu, int mnemonic, String actionCommand,
			ActionListener listener) {
		menuItem.setMnemonic(mnemonic);
		addMenuItem(menuItem, menu, actionCommand, listener);
	}

	private static void addMenuItem(JMenuItem menuItem, JMenu menu, String actionCommand,
			ActionListener listener) {
		menuItem.setActionCommand(actionCommand);
		menuItem.addActionListener(listener);
		menu.add(menuItem);
	}

	private static void replaceCanvas() {
		canvas.stop();
		canvas.removeAll();
		FRAME.remove(canvas);
		setCanvas();
	}

	private static void setCanvas() {
		canvas = getCanvas();
		FRAME.add(canvas);
		FRAME.pack();
	}

	private static Canvas getCanvas() {
		File skinFile = new File(SKINS_DIR, skin);
		if (difficulty == null) {
			// TODO: Make the difficulty actually change
			return new Canvas(40, 50, 500, skinFile);
		}
		return new Canvas(difficulty.ROWS, difficulty.COLS, difficulty.MINES, skinFile);
	}

	// No construction >:(
	private Main() {
	}
}