/**** 
* Plugins
****/ 
var tween = LK.import("@upit/tween.v1");

/**** 
* Classes
****/ 
// PuzzleTile: Represents a single tile in the puzzle grid.
var PuzzleTile = Container.expand(function () {
	var self = Container.call(this);
	// Properties
	self.gridX = 0; // grid position x
	self.gridY = 0; // grid position y
	self.correctX = 0; // correct grid position x
	self.correctY = 0; // correct grid position y
	self.tileIndex = 0; // index in the tile array
	self.isEmpty = false; // is this the empty tile?
	// The tile's visual
	var tileAsset = self.attachAsset('tile', {
		anchorX: 0,
		anchorY: 0
	});
	// For MVP, we color each tile differently for visual distinction
	self.setColor = function (color) {
		tileAsset.color = color;
		tileAsset.tint = color;
	};
	// Set the label (number) for the tile
	self.setLabel = function (label) {
		if (self.labelText) {
			self.labelText.setText(label);
		} else {
			var txt = new Text2(label + '', {
				size: 120,
				fill: 0x222222
			});
			txt.anchor.set(0.5, 0.5);
			txt.x = tileAsset.width / 2;
			txt.y = tileAsset.height / 2;
			self.addChild(txt);
			self.labelText = txt;
		}
	};
	// Hide label for empty tile
	self.hideLabel = function () {
		if (self.labelText) {
			self.labelText.visible = false;
		}
	};
	// Show label
	self.showLabel = function () {
		if (self.labelText) {
			self.labelText.visible = true;
		}
	};
	// Animate to a new position
	self.moveTo = function (x, y, duration) {
		tween(self, {
			x: x,
			y: y
		}, {
			duration: duration || 200,
			easing: tween.cubicOut
		});
	};
	return self;
});

/**** 
* Initialize Game
****/ 
var game = new LK.Game({
	backgroundColor: 0x222222
});

/**** 
* Game Code
****/ 
// In the future, this can be replaced with a real image or a procedurally generated pattern.
// For MVP, we use a colored box as a placeholder for each tile, with a random color per game.
// We'll use a single image asset for the puzzle, which will be randomly generated each game.
// --- Puzzle Settings ---
var gridSize = 4; // 4x4 grid (15-puzzle style)
var tileSize = 400; // px, will be scaled to fit screen
var tileSpacing = 12; // px gap between tiles
var puzzleOffsetX = 0;
var puzzleOffsetY = 0;
var puzzleWidth = gridSize * tileSize + (gridSize - 1) * tileSpacing;
var puzzleHeight = gridSize * tileSize + (gridSize - 1) * tileSpacing;
// --- State ---
var tiles = []; // 2D array [y][x] of PuzzleTile
var tileList = []; // flat array of all PuzzleTile
var emptyTile = null; // reference to the empty tile
var moveCount = 0;
var startTime = 0;
var timerInterval = null;
var isSolved = false;
// --- UI ---
var moveText = new Text2('Moves: 0', {
	size: 90,
	fill: 0xFFFFFF
});
moveText.anchor.set(0.5, 0);
LK.gui.top.addChild(moveText);
var timeText = new Text2('Time: 0s', {
	size: 90,
	fill: 0xFFFFFF
});
timeText.anchor.set(0.5, 0);
LK.gui.top.addChild(timeText);
// Position UI
moveText.x = LK.gui.top.width / 2 - 200;
moveText.y = 20;
timeText.x = LK.gui.top.width / 2 + 200;
timeText.y = 20;
// --- Remix Button ---
var remixBtn = new Text2('Remix', {
	size: 90,
	fill: 0xFFD700
});
remixBtn.anchor.set(0.5, 0);
remixBtn.x = LK.gui.top.width / 2;
remixBtn.y = 120;
remixBtn.interactive = true;
remixBtn.buttonMode = true;
remixBtn.down = function (x, y, obj) {
	if (isSolved) return;
	shufflePuzzle();
	moveCount = 0;
	startTime = Date.now();
	updateUI();
};
LK.gui.top.addChild(remixBtn);
// --- Helper Functions ---
// Generate a random color palette for the puzzle
function generateColorPalette(n) {
	var colors = [];
	var baseHue = Math.floor(Math.random() * 360);
	for (var i = 0; i < n; i++) {
		// HSL to RGB conversion
		var hue = (baseHue + i * (360 / n)) % 360;
		var rgb = hslToRgb(hue / 360, 0.6, 0.6);
		var color = rgb[0] << 16 | rgb[1] << 8 | rgb[2];
		colors.push(color);
	}
	return colors;
}
// HSL to RGB helper
function hslToRgb(h, s, l) {
	var r, g, b;
	if (s == 0) {
		r = g = b = l;
	} else {
		var hue2rgb = function hue2rgb(p, q, t) {
			if (t < 0) t += 1;
			if (t > 1) t -= 1;
			if (t < 1 / 6) return p + (q - p) * 6 * t;
			if (t < 1 / 2) return q;
			if (t < 2 / 3) return p + (q - p) * (2 / 3 - t) * 6;
			return p;
		};
		var q = l < 0.5 ? l * (1 + s) : l + s - l * s;
		var p = 2 * l - q;
		r = hue2rgb(p, q, h + 1 / 3);
		g = hue2rgb(p, q, h);
		b = hue2rgb(p, q, h - 1 / 3);
	}
	return [Math.round(r * 255), Math.round(g * 255), Math.round(b * 255)];
}
// Shuffle an array in-place
function shuffleArray(arr) {
	for (var i = arr.length - 1; i > 0; i--) {
		var j = Math.floor(Math.random() * (i + 1));
		var tmp = arr[i];
		arr[i] = arr[j];
		arr[j] = tmp;
	}
}
// Check if the puzzle is solved
function checkSolved() {
	for (var y = 0; y < gridSize; y++) {
		for (var x = 0; x < gridSize; x++) {
			var tile = tiles[y][x];
			if (tile.gridX !== tile.correctX || tile.gridY !== tile.correctY) {
				return false;
			}
		}
	}
	return true;
}
// Update move and time UI
function updateUI() {
	moveText.setText('Moves: ' + moveCount);
	var elapsed = Math.floor((Date.now() - startTime) / 1000);
	timeText.setText('Time: ' + elapsed + 's');
}
// --- Puzzle Generation ---
function createPuzzle() {
	// Remove old tiles
	for (var i = 0; i < tileList.length; i++) {
		tileList[i].destroy();
	}
	tiles = [];
	tileList = [];
	emptyTile = null;
	isSolved = false;
	moveCount = 0;
	updateUI();
	// Generate color palette
	var numTiles = gridSize * gridSize;
	var colors = generateColorPalette(numTiles - 1);
	// Calculate tile size to fit screen
	var maxWidth = 2048 - 200;
	var maxHeight = 2732 - 400;
	tileSize = Math.floor(Math.min((maxWidth - (gridSize - 1) * tileSpacing) / gridSize, (maxHeight - (gridSize - 1) * tileSpacing) / gridSize));
	puzzleWidth = gridSize * tileSize + (gridSize - 1) * tileSpacing;
	puzzleHeight = gridSize * tileSize + (gridSize - 1) * tileSpacing;
	puzzleOffsetX = Math.floor((2048 - puzzleWidth) / 2);
	puzzleOffsetY = Math.floor((2732 - puzzleHeight) / 2) + 80;
	// Create tiles in solved order
	var idx = 0;
	for (var y = 0; y < gridSize; y++) {
		tiles[y] = [];
		for (var x = 0; x < gridSize; x++) {
			var tile = new PuzzleTile();
			tile.gridX = x;
			tile.gridY = y;
			tile.correctX = x;
			tile.correctY = y;
			tile.tileIndex = idx;
			tile.x = puzzleOffsetX + x * (tileSize + tileSpacing);
			tile.y = puzzleOffsetY + y * (tileSize + tileSpacing);
			tile.width = tileSize;
			tile.height = tileSize;
			tile.setColor(colors[idx] || 0x222222);
			tile.setLabel(idx + 1);
			tile.isEmpty = false;
			tileList.push(tile);
			tiles[y][x] = tile;
			game.addChild(tile);
			idx++;
		}
	}
	// Make last tile the empty tile
	var lastTile = tiles[gridSize - 1][gridSize - 1];
	lastTile.isEmpty = true;
	lastTile.setColor(0x222222);
	lastTile.hideLabel();
	emptyTile = lastTile;
	// Shuffle tiles
	shufflePuzzle();
	// Start timer
	startTime = Date.now();
	if (timerInterval) LK.clearInterval(timerInterval);
	timerInterval = LK.setInterval(updateUI, 500);
}
// Shuffle the puzzle by simulating random valid moves
function shufflePuzzle() {
	var moves = [[0, 1], [1, 0], [0, -1], [-1, 0]];
	var prevX = emptyTile.gridX,
		prevY = emptyTile.gridY;
	var shuffleCount = 200 + Math.floor(Math.random() * 100);
	for (var i = 0; i < shuffleCount; i++) {
		var possible = [];
		for (var d = 0; d < moves.length; d++) {
			var nx = emptyTile.gridX + moves[d][0];
			var ny = emptyTile.gridY + moves[d][1];
			if (nx >= 0 && nx < gridSize && ny >= 0 && ny < gridSize) {
				if (!(nx === prevX && ny === prevY)) {
					possible.push([nx, ny]);
				}
			}
		}
		if (possible.length === 0) continue;
		var pick = possible[Math.floor(Math.random() * possible.length)];
		var tile = tiles[pick[1]][pick[0]];
		swapWithEmpty(tile, false);
		prevX = emptyTile.gridX;
		prevY = emptyTile.gridY;
	}
	// After shuffling, update all tile positions visually
	for (var y = 0; y < gridSize; y++) {
		for (var x = 0; x < gridSize; x++) {
			var tile = tiles[y][x];
			tile.x = puzzleOffsetX + x * (tileSize + tileSpacing);
			tile.y = puzzleOffsetY + y * (tileSize + tileSpacing);
			tile.gridX = x;
			tile.gridY = y;
		}
	}
}
// Swap a tile with the empty tile (if adjacent)
function swapWithEmpty(tile, animate) {
	if (tile.isEmpty) return false;
	var dx = Math.abs(tile.gridX - emptyTile.gridX);
	var dy = Math.abs(tile.gridY - emptyTile.gridY);
	if (dx === 1 && dy === 0 || dx === 0 && dy === 1) {
		// Swap in tiles array
		var tx = tile.gridX,
			ty = tile.gridY;
		var ex = emptyTile.gridX,
			ey = emptyTile.gridY;
		tiles[ty][tx] = emptyTile;
		tiles[ey][ex] = tile;
		// Swap grid positions
		var tmpX = tile.gridX,
			tmpY = tile.gridY;
		tile.gridX = emptyTile.gridX;
		tile.gridY = emptyTile.gridY;
		emptyTile.gridX = tmpX;
		emptyTile.gridY = tmpY;
		// Animate movement
		var tileTargetX = puzzleOffsetX + tile.gridX * (tileSize + tileSpacing);
		var tileTargetY = puzzleOffsetY + tile.gridY * (tileSize + tileSpacing);
		var emptyTargetX = puzzleOffsetX + emptyTile.gridX * (tileSize + tileSpacing);
		var emptyTargetY = puzzleOffsetY + emptyTile.gridY * (tileSize + tileSpacing);
		if (animate !== false) {
			tile.moveTo(tileTargetX, tileTargetY, 120);
			emptyTile.moveTo(emptyTargetX, emptyTargetY, 120);
		} else {
			tile.x = tileTargetX;
			tile.y = tileTargetY;
			emptyTile.x = emptyTargetX;
			emptyTile.y = emptyTargetY;
		}
		return true;
	}
	return false;
}
// --- Input Handling ---
// Find which tile was pressed
function getTileAtPos(x, y) {
	for (var i = 0; i < tileList.length; i++) {
		var tile = tileList[i];
		if (tile.isEmpty) continue;
		var tx = tile.x,
			ty = tile.y;
		var tw = tile.width,
			th = tile.height;
		if (x >= tx && x <= tx + tw && y >= ty && y <= ty + th) {
			return tile;
		}
	}
	return null;
}
// Handle tap/click on the puzzle
game.down = function (x, y, obj) {
	if (isSolved) return;
	var tile = getTileAtPos(x, y);
	if (!tile) return;
	var moved = swapWithEmpty(tile, true);
	if (moved) {
		moveCount++;
		updateUI();
		if (checkSolved()) {
			isSolved = true;
			updateUI();
			LK.effects.flashScreen(0x44ff44, 800);
			LK.setTimeout(function () {
				LK.showYouWin();
			}, 900);
		}
	}
};
// --- Game Update ---
game.update = function () {
	// No per-frame logic needed for MVP
};
// --- Start Game ---
createPuzzle();