import java.awt.*;
import java.util.HashSet;
import java.awt.event.*;
import javax.swing.*;

public class Tile extends JComponent {
	public static final int SIZE = 16;
	public static final int REGULAR_INDEX = 0;
	public static final int PRESSED_INDEX = 1;
	public static final int MINE_INDEX = 2;
	public static final int FLAGGED_INDEX = 3;
	public static final int NOT_MINE_INDEX = 4;
	public static final int EXPLODED_MINE_INDEX = 5;

	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
	// numbers and autorevealing zeros and chording
	private final HashSet<Tile> ADJACENT_TILES;

	// 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
	private boolean revealed;
	// Whether or not this mine has been flagged
	private boolean flagged;
	private boolean pressed;
	private boolean mouseOver;
	private boolean gameEnded;

	private void init() {
		mine = false;
		num = 0;
		revealed = false;
		flagged = false;
		pressed = false;
		mouseOver = false;
		gameEnded = false;
		addMouseListener(TILE_MOUSE_LISTENER);
	}

	public Tile(Canvas gameCanvas, Image[] numberTiles, Image[] specialTiles) {
		GAME_CANVAS = gameCanvas;
		NUMBER_TILES = numberTiles;
		SPECIAL_TILES = specialTiles;
		ADJACENT_TILES = new HashSet<Tile>();

		TILE_MOUSE_LISTENER = new MouseAdapter() {
			@Override
			public void mousePressed(MouseEvent e) {
				boolean rightClicked = false;
				switch (e.getButton()) {
				case MouseEvent.BUTTON1:
					GAME_CANVAS.setLeftMouseDown(true);
					break;
				case MouseEvent.BUTTON3:
					rightClicked = true;
					GAME_CANVAS.setRightMouseDown(true);
					break;
				default:
					return;
				}

				Tile tile = GAME_CANVAS.getCurrentTile();
				if (tile == null)
					return;

				if (rightClicked)
					tile.rightClickAction();
				tile.updatePressedState();
			}

			@Override
			public void mouseReleased(MouseEvent e) {
				boolean leftClicked = false;
				switch (e.getButton()) {
				case MouseEvent.BUTTON1:
					leftClicked = true;
					GAME_CANVAS.setLeftMouseDown(false);
					break;
				case MouseEvent.BUTTON3:
					GAME_CANVAS.setRightMouseDown(false);
					break;
				default:
					return;
				}

				Tile tile = GAME_CANVAS.getCurrentTile();
				if (tile == null)
					return;

				if (leftClicked)
					tile.leftClickAction();
				tile.updatePressedState();
			}

			@Override
			public void mouseEntered(MouseEvent e) {
				GAME_CANVAS.setCurrentTile(Tile.this);
				mouseOver = true;
				updatePressedState();
			}

			@Override
			public void mouseExited(MouseEvent e) {
				if (GAME_CANVAS.getCurrentTile() == Tile.this)
					GAME_CANVAS.setCurrentTile(null);
				mouseOver = false;
				updatePressedState();
			}
		};

		setPreferredSize(new Dimension(SIZE, SIZE));

		init();
	}

	public void restart() {
		removeMouseListener(TILE_MOUSE_LISTENER);
		init();
	}

	public void addAdjacentTile(Tile tile) {
		ADJACENT_TILES.add(tile);
	}

	// At the start of the game, place a mine at this tile, unless it is
	// adjacent to or is the starting tile, or is already a mine. Returns
	// whether or not a mine was actually placed.
	public boolean makeMine(Tile startTile) {
		if (mine || this == startTile || Options.isProtectedStart() && ADJACENT_TILES.contains(startTile))
			return false;

		mine = true;
		// Increment the number on the adjacent tiles when a new mine is decided
		for (Tile tile : ADJACENT_TILES)
			tile.num++;
		return true;
	}

	public void gameEnd() {
		removeMouseListener(TILE_MOUSE_LISTENER);
		gameEnded = true;
		// Only repaint the tiles that actually change
		if (mine || flagged)
			repaint();
	}

	public void updatePressedState() {
		if (pressed != (GAME_CANVAS.isLeftMouseDown() && mouseOver)) {
			pressed = !pressed;
			repaint();
		}
		boolean pressAdjacent = pressed && GAME_CANVAS.isChording();
		for (Tile tile : ADJACENT_TILES) {
			if (tile.pressed != pressAdjacent) {
				tile.pressed = pressAdjacent;
				tile.repaint();
			}
		}
	}

	private void rightClickAction() {
		if (revealed)
			return;

		flagged = !flagged;
		GAME_CANVAS.modifyFlagCount(flagged);
		repaint();
	}

	private void leftClickAction() {
		if (GAME_CANVAS.isChording()) {
			if (!revealed)
				return;

			int adjacentFlags = 0;
			for (Tile tile : ADJACENT_TILES)
				if (tile.flagged)
					adjacentFlags++;
			if (adjacentFlags != num)
				return;

			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();
		}
		GAME_CANVAS.postRevealCheck();
	}

	private void reveal() {
		if (revealed)
			return;

		revealed = true;
		repaint();

		if (mine) {
			GAME_CANVAS.setLoseFlag();
		} else {
			GAME_CANVAS.revealedSingleTile();
			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];
			if (revealed)
				return SPECIAL_TILES[EXPLODED_MINE_INDEX];
			return SPECIAL_TILES[MINE_INDEX];
		}
		if (revealed)
			return NUMBER_TILES[num];
		if (flagged) {
			// Correctly flagged mines would have been caught earlier
			if (gameEnded)
				return SPECIAL_TILES[NOT_MINE_INDEX];
			return SPECIAL_TILES[FLAGGED_INDEX];
		}
		// Tiles are only interactable if the game is ongoing
		if (pressed && !gameEnded)
			return SPECIAL_TILES[PRESSED_INDEX];
		return SPECIAL_TILES[REGULAR_INDEX];
	}

	@Override
	public void paintComponent(Graphics gr) {
		super.paintComponent(gr);
		Graphics2D g = (Graphics2D) gr;

		g.drawImage(getImage(), 0, 0, this);
	}
}