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

/**** 
* Classes
****/ 
// Hero class: follows face position
var Hero = Container.expand(function () {
	var self = Container.call(this);
	var heroAsset = self.attachAsset('hero', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	// For collision detection, keep radius
	self.radius = heroAsset.width / 2;
	// No update needed; position is set by facekit in main game loop
	return self;
});
// Obstacle class: moves horizontally or vertically
var Obstacle = Container.expand(function () {
	var self = Container.call(this);
	var obstacleAsset = self.attachAsset('obstacle', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	// Movement direction: 'horizontal' or 'vertical'
	self.direction = 'horizontal';
	self.speed = 8;
	self.amplitude = 400;
	self.baseX = 0;
	self.baseY = 0;
	self.phase = 0;
	self.width = obstacleAsset.width;
	self.height = obstacleAsset.height;
	// For collision, use bounding box
	self.update = function () {
		if (self.direction === 'horizontal') {
			self.x = self.baseX + Math.sin((LK.ticks + self.phase) * 0.02) * self.amplitude;
		} else {
			self.y = self.baseY + Math.sin((LK.ticks + self.phase) * 0.02) * self.amplitude;
		}
	};
	return self;
});
// Target class: collectible, static
var Target = Container.expand(function () {
	var self = Container.call(this);
	var targetAsset = self.attachAsset('target', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.radius = targetAsset.width / 2;
	// No update needed; handled in main game loop
	return self;
});

/**** 
* Initialize Game
****/ 
var game = new LK.Game({
	backgroundColor: 0x181c24
});

/**** 
* Game Code
****/ 
// Music (optional, will not be played in MVP)
// Sound for hitting obstacle
// Sound for collecting target
// Obstacle: box, red, variable size
// Target: ellipse, green, smaller
// Hero: ellipse, bright color, medium size
// Game area: 2048x2732
// Keep all gameplay elements away from top-left 100x100
// Score display
var scoreTxt = new Text2('0', {
	size: 120,
	fill: 0xFFFFFF
});
scoreTxt.anchor.set(0.5, 0);
LK.gui.top.addChild(scoreTxt);
// Main game objects
var hero = new Hero();
game.addChild(hero);
// Target
var target = null;
// Obstacles array
var obstacles = [];
// Game state
var score = 0;
var difficulty = 1;
var lastTargetTime = 0;
var lastObstacleTime = 0;
var gameStarted = false;
var gameOver = false;
// Helper: clamp hero inside screen
function clampHeroPosition(x, y) {
	var r = hero.radius;
	var minX = r + 40;
	var maxX = 2048 - r - 40;
	var minY = r + 140; // leave space for GUI
	var maxY = 2732 - r - 40;
	if (x < minX) x = minX;
	if (x > maxX) x = maxX;
	if (y < minY) y = minY;
	if (y > maxY) y = maxY;
	return {
		x: x,
		y: y
	};
}
// Helper: random position for target, not too close to hero or edges
function randomTargetPosition() {
	var margin = 200;
	var r = 0;
	var tx = 0,
		ty = 0;
	do {
		tx = margin + Math.random() * (2048 - 2 * margin);
		ty = margin + 200 + Math.random() * (2732 - 2 * margin - 200);
		r = Math.sqrt((tx - hero.x) * (tx - hero.x) + (ty - hero.y) * (ty - hero.y));
	} while (r < 400); // not too close to hero
	return {
		x: tx,
		y: ty
	};
}
// Helper: spawn target
function spawnTarget() {
	if (target) {
		target.destroy();
	}
	target = new Target();
	var pos = randomTargetPosition();
	target.x = pos.x;
	target.y = pos.y;
	game.addChild(target);
}
// Helper: spawn obstacle
function spawnObstacle() {
	var obs = new Obstacle();
	// Randomize direction
	obs.direction = Math.random() < 0.5 ? 'horizontal' : 'vertical';
	obs.amplitude = 200 + Math.random() * 600;
	obs.phase = Math.floor(Math.random() * 1000);
	obs.speed = 6 + difficulty * 2 + Math.random() * 2;
	// Randomize base position, avoid top 200px and bottom 200px
	if (obs.direction === 'horizontal') {
		obs.baseY = 300 + Math.random() * (2732 - 600);
		obs.baseX = 1024;
		obs.x = obs.baseX;
		obs.y = obs.baseY;
	} else {
		obs.baseX = 300 + Math.random() * (2048 - 600);
		obs.baseY = 1366;
		obs.x = obs.baseX;
		obs.y = obs.baseY;
	}
	obstacles.push(obs);
	game.addChild(obs);
}
// Helper: check collision (circle vs circle)
function circlesIntersect(x1, y1, r1, x2, y2, r2) {
	var dx = x1 - x2;
	var dy = y1 - y2;
	var dist = dx * dx + dy * dy;
	var rad = r1 + r2;
	return dist <= rad * rad;
}
// Helper: check collision (circle vs box)
function circleBoxIntersect(cx, cy, cr, bx, by, bw, bh) {
	// bx,by: center of box
	var dx = Math.abs(cx - bx);
	var dy = Math.abs(cy - by);
	var hw = bw / 2;
	var hh = bh / 2;
	if (dx > hw + cr) return false;
	if (dy > hh + cr) return false;
	if (dx <= hw) return true;
	if (dy <= hh) return true;
	var cornerDist = (dx - hw) * (dx - hw) + (dy - hh) * (dy - hh);
	return cornerDist <= cr * cr;
}
// Helper: increase difficulty
function updateDifficulty() {
	difficulty = 1 + Math.floor(score / 5);
}
// Game start: place hero in center, spawn target, clear obstacles
function startGame() {
	score = 0;
	scoreTxt.setText(score);
	gameOver = false;
	// Place hero in center
	hero.x = 2048 / 2;
	hero.y = 2732 / 2;
	// Remove old target
	if (target) {
		target.destroy();
		target = null;
	}
	// Remove obstacles
	for (var i = 0; i < obstacles.length; ++i) {
		obstacles[i].destroy();
	}
	obstacles = [];
	// Spawn first target
	spawnTarget();
	// Spawn initial obstacles
	for (var i = 0; i < 2; ++i) {
		spawnObstacle();
	}
	lastTargetTime = LK.ticks;
	lastObstacleTime = LK.ticks;
	updateDifficulty();
	gameStarted = true;
}
// Game over
function triggerGameOver() {
	if (gameOver) return;
	gameOver = true;
	LK.effects.flashScreen(0xff0000, 800);
	LK.getSound('hit').play();
	LK.showGameOver();
}
// Main update loop
game.update = function () {
	// If game is not started, wait for facekit to be ready and face detected before starting
	if (!gameStarted) {
		// Wait for facekit to be initialized and a face to be detected
		if (facekit.ready && facekit.mouthCenter && facekit.mouthCenter.x && facekit.mouthCenter.y) {
			startGame();
		}
		return;
	}
	if (gameOver) return;
	// 1. Update hero position from facekit
	var fx = facekit.mouthCenter.x;
	var fy = facekit.mouthCenter.y;
	// If facekit not ready, keep hero in center
	if (!fx || !fy) {
		fx = 2048 / 2;
		fy = 2732 / 2;
	}
	var pos = clampHeroPosition(fx, fy);
	hero.x = pos.x;
	hero.y = pos.y;
	// 2. Update obstacles
	for (var i = obstacles.length - 1; i >= 0; --i) {
		var obs = obstacles[i];
		obs.update();
		// Remove obstacles that have drifted off screen (shouldn't happen, but safety)
		if (obs.x < -300 || obs.x > 2348 || obs.y < -300 || obs.y > 3032) {
			obs.destroy();
			obstacles.splice(i, 1);
		}
	}
	// 3. Check collision: hero vs target
	if (target && circlesIntersect(hero.x, hero.y, hero.radius, target.x, target.y, target.radius)) {
		// Collect target
		LK.getSound('collect').play();
		score += 1;
		scoreTxt.setText(score);
		spawnTarget();
		updateDifficulty();
		// Add new obstacle every 3 points, up to 8
		if (score % 3 === 0 && obstacles.length < 8) {
			spawnObstacle();
		}
	}
	// 4. Check collision: hero vs obstacles
	for (var j = 0; j < obstacles.length; ++j) {
		var obs2 = obstacles[j];
		if (circleBoxIntersect(hero.x, hero.y, hero.radius * 0.85, obs2.x, obs2.y, obs2.width, obs2.height)) {
			triggerGameOver();
			return;
		}
	}
	// 5. Increase obstacle speed with difficulty
	for (var k = 0; k < obstacles.length; ++k) {
		obstacles[k].amplitude = 200 + difficulty * 60 + Math.random() * 100;
		obstacles[k].speed = 6 + difficulty * 2 + Math.random() * 2;
	}
};
// No touch controls needed; facekit only
// On game over, restart on next update
LK.on('gameover', function () {
	// Wait for LK to reset, then restart
	gameStarted = false;
});
// On you win (not used in MVP, but for future)
LK.on('youwin', function () {
	gameStarted = false;
});

===================================================================
--- original.js
+++ change.js
@@ -226,11 +226,14 @@
 	LK.showGameOver();
 }
 // Main update loop
 game.update = function () {
-	// If game is not started, start it
+	// If game is not started, wait for facekit to be ready and face detected before starting
 	if (!gameStarted) {
-		startGame();
+		// Wait for facekit to be initialized and a face to be detected
+		if (facekit.ready && facekit.mouthCenter && facekit.mouthCenter.x && facekit.mouthCenter.y) {
+			startGame();
+		}
 		return;
 	}
 	if (gameOver) return;
 	// 1. Update hero position from facekit