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

/**** 
* Classes
****/ 
// Bird class
var Bird = Container.expand(function () {
	var self = Container.call(this);
	// Attach a red ellipse as the bird
	var birdAsset = self.attachAsset('bird', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	// Physics properties
	self.vx = 0;
	self.vy = 0;
	self.launched = false;
	self.radius = birdAsset.width / 2;
	self.gravity = 0.7;
	self.friction = 0.995;
	self.bounce = 0.5;
	self.stopped = false;
	// Called every tick
	self.update = function () {
		// Track lastX and lastY for physics events
		if (typeof self.lastX === "undefined") self.lastX = self.x;
		if (typeof self.lastY === "undefined") self.lastY = self.y;
		if (self.launched && !self.stopped) {
			// Standard projectile physics, no tracking or homing
			self.vy += self.gravity;
			self.x += self.vx;
			self.y += self.vy;
			// Friction
			self.vx *= self.friction;
			self.vy *= self.friction;
			// Floor collision
			if (self.y + self.radius > groundY) {
				self.y = groundY - self.radius;
				if (Math.abs(self.vy) > 2) {
					self.vy = -self.vy * self.bounce;
					self.vx *= 0.8;
				} else {
					self.vy = 0;
					self.vx *= 0.8;
					if (Math.abs(self.vx) < 1) {
						self.stopped = true;
					}
				}
			}
			// Wall collision
			if (self.x - self.radius < 0) {
				self.x = self.radius;
				self.vx = -self.vx * self.bounce;
			}
			if (self.x + self.radius > 2048) {
				self.x = 2048 - self.radius;
				self.vx = -self.vx * self.bounce;
			}
		}
		// Update lastX and lastY after movement
		self.lastX = self.x;
		self.lastY = self.y;
	};
	// Simple circle collision
	self.intersectsCircle = function (other) {
		var dx = self.x - other.x;
		var dy = self.y - other.y;
		var dist = Math.sqrt(dx * dx + dy * dy);
		return dist < self.radius + other.radius;
	};
	return self;
});
// Block class (rectangular, can be horizontal or vertical)
var Block = Container.expand(function () {
	var self = Container.call(this);
	// Attach a brown box as the block
	var blockAsset = self.attachAsset('block', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.width = blockAsset.width;
	self.height = blockAsset.height;
	self.vx = 0;
	self.vy = 0;
	self.gravity = 0.7;
	self.friction = 0.98;
	self.bounce = 0.3;
	self.stopped = false;
	// Called every tick
	self.update = function () {
		if (!self.stopped) {
			self.vy += self.gravity;
			self.x += self.vx;
			self.y += self.vy;
			self.vx *= self.friction;
			self.vy *= self.friction;
			// Floor collision
			if (self.y + self.height / 2 > groundY) {
				self.y = groundY - self.height / 2;
				if (Math.abs(self.vy) > 2) {
					self.vy = -self.vy * self.bounce;
					self.vx *= 0.8;
				} else {
					self.vy = 0;
					self.vx *= 0.8;
					if (Math.abs(self.vx) < 1) {
						self.stopped = true;
					}
				}
			}
			// Wall collision
			if (self.x - self.width / 2 < 0) {
				self.x = self.width / 2;
				self.vx = -self.vx * self.bounce;
			}
			if (self.x + self.width / 2 > 2048) {
				self.x = 2048 - self.width / 2;
				self.vx = -self.vx * self.bounce;
			}
		}
	};
	// Simple rectangle collision with circle (bird)
	self.intersectsCircle = function (circle) {
		var cx = circle.x;
		var cy = circle.y;
		var rx = self.x;
		var ry = self.y;
		var hw = self.width / 2;
		var hh = self.height / 2;
		// Closest point on rectangle to circle center
		var closestX = Math.max(rx - hw, Math.min(cx, rx + hw));
		var closestY = Math.max(ry - hh, Math.min(cy, ry + hh));
		var dx = cx - closestX;
		var dy = cy - closestY;
		return dx * dx + dy * dy < circle.radius * circle.radius;
	};
	return self;
});
// Pig class
var Pig = Container.expand(function () {
	var self = Container.call(this);
	// Attach a green ellipse as the pig
	var pigAsset = self.attachAsset('pig', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.radius = pigAsset.width / 2;
	self.alive = true;
	// Physics properties for pigs
	self.vx = 0;
	self.vy = 0;
	self.gravity = 0.7;
	self.friction = 0.98;
	self.bounce = 0.3;
	self.stopped = false;
	// Called every tick
	self.update = function () {
		if (!self.alive) return;
		// Track lastX and lastY for physics events
		if (typeof self.lastX === "undefined") self.lastX = self.x;
		if (typeof self.lastY === "undefined") self.lastY = self.y;
		if (!self.stopped) {
			self.vy += self.gravity;
			self.x += self.vx;
			self.y += self.vy;
			self.vx *= self.friction;
			self.vy *= self.friction;
			// Floor collision
			if (self.y + self.radius > groundY) {
				self.y = groundY - self.radius;
				if (Math.abs(self.vy) > 2) {
					self.vy = -self.vy * self.bounce;
					self.vx *= 0.8;
				} else {
					self.vy = 0;
					self.vx *= 0.8;
					if (Math.abs(self.vx) < 1) {
						self.stopped = true;
					}
				}
			}
			// Wall collision
			if (self.x - self.radius < 0) {
				self.x = self.radius;
				self.vx = -self.vx * self.bounce;
			}
			if (self.x + self.radius > 2048) {
				self.x = 2048 - self.radius;
				self.vx = -self.vx * self.bounce;
			}
		}
		// Update lastX and lastY after movement
		self.lastX = self.x;
		self.lastY = self.y;
	};
	return self;
});

/**** 
* Initialize Game
****/ 
var game = new LK.Game({
	backgroundColor: 0x87ceeb // Sky blue
});

/**** 
* Game Code
****/ 
// --- Game Variables ---
// --- Asset Initialization (shapes) ---
var birds = [];
var pigs = [];
var blocks = [];
var currentBird = null;
var birdIndex = 0;
var isDragging = false;
var dragStart = {
	x: 0,
	y: 0
};
var dragEnd = {
	x: 0,
	y: 0
};
var slingshotX = 180;
var slingshotY = 2450;
var slingshotBandLength = 180;
var maxBirds = 3;
var groundY = 2650;
var level = 1;
var launching = false;
var score = 0;
// --- GUI ---
var scoreTxt = new Text2('0', {
	size: 120,
	fill: 0xFFFFFF
});
scoreTxt.anchor.set(0.5, 0);
LK.gui.top.addChild(scoreTxt);
var birdsLeftTxt = new Text2('', {
	size: 80,
	fill: 0xFFFFFF
});
birdsLeftTxt.anchor.set(0.5, 0);
LK.gui.topRight.addChild(birdsLeftTxt);
// --- Draw Ground ---
var ground = LK.getAsset('ground', {
	anchorX: 0,
	anchorY: 0
});
ground.x = 0;
ground.y = groundY;
game.addChild(ground);
// --- Draw Slingshot ---
var slingshot = LK.getAsset('slingshot', {
	anchorX: 0.5,
	anchorY: 1
});
slingshot.x = slingshotX;
slingshot.y = slingshotY + 90;
game.addChild(slingshot);
// --- Level Setup ---
function setupLevel() {
	// Clear previous
	for (var i = 0; i < birds.length; i++) birds[i].destroy();
	for (var i = 0; i < pigs.length; i++) pigs[i].destroy();
	for (var i = 0; i < blocks.length; i++) blocks[i].destroy();
	birds = [];
	pigs = [];
	blocks = [];
	birdIndex = 0;
	score = 0;
	LK.setScore(0);
	scoreTxt.setText('0');
	launching = false;
	// Place birds
	for (var i = 0; i < maxBirds; i++) {
		var bird = new Bird();
		bird.x = slingshotX - 120 - i * 80;
		bird.y = slingshotY + 40;
		birds.push(bird);
		game.addChild(bird);
	}
	currentBird = birds[birdIndex];
	// Place blocks (simple structure, now using Block class with physics)
	var block1 = new Block();
	block1.x = 1500;
	block1.y = groundY - 100;
	blocks.push(block1);
	game.addChild(block1);
	var block2 = new Block();
	block2.x = 1500 - 100;
	block2.y = groundY - 60;
	blocks.push(block2);
	game.addChild(block2);
	var block3 = new Block();
	block3.x = 1500 + 100;
	block3.y = groundY - 60;
	blocks.push(block3);
	game.addChild(block3);
	// Place pigs on top of blocks
	var pig1 = new Pig();
	pig1.x = block1.x;
	pig1.y = block1.y - block1.height / 2 - pig1.radius;
	pigs.push(pig1);
	game.addChild(pig1);
	var pig2 = new Pig();
	pig2.x = block2.x;
	pig2.y = block2.y - block2.height / 2 - pig2.radius;
	pigs.push(pig2);
	game.addChild(pig2);
	var pig3 = new Pig();
	pig3.x = block3.x;
	pig3.y = block3.y - block3.height / 2 - pig3.radius;
	pigs.push(pig3);
	game.addChild(pig3);
	updateBirdsLeft();
}
// --- Update birds left text ---
function updateBirdsLeft() {
	birdsLeftTxt.setText('Birds: ' + (maxBirds - birdIndex));
}
// --- Drag and Launch Logic ---
function getDistance(x1, y1, x2, y2) {
	var dx = x2 - x1;
	var dy = y2 - y1;
	return Math.sqrt(dx * dx + dy * dy);
}
function getAngle(x1, y1, x2, y2) {
	return Math.atan2(y2 - y1, x2 - x1);
}
// Only allow drag if not launched
game.down = function (x, y, obj) {
	if (launching) return;
	if (!currentBird || currentBird.launched) return;
	// Only allow drag if touch is near the bird
	var dist = getDistance(x, y, currentBird.x, currentBird.y);
	if (dist < currentBird.radius * 1.5) {
		isDragging = true;
		dragStart.x = x;
		dragStart.y = y;
	}
};
game.move = function (x, y, obj) {
	if (isDragging && currentBird && !currentBird.launched) {
		// Limit drag distance
		var dx = x - slingshotX;
		var dy = y - slingshotY;
		var dist = getDistance(x, y, slingshotX, slingshotY);
		if (dist > slingshotBandLength) {
			var angle = getAngle(slingshotX, slingshotY, x, y);
			dx = Math.cos(angle) * slingshotBandLength;
			dy = Math.sin(angle) * slingshotBandLength;
		}
		currentBird.x = slingshotX + dx;
		currentBird.y = slingshotY + dy;
		dragEnd.x = currentBird.x;
		dragEnd.y = currentBird.y;
	}
};
game.up = function (x, y, obj) {
	if (isDragging && currentBird && !currentBird.launched) {
		isDragging = false;
		// Calculate launch velocity
		var dx = slingshotX - currentBird.x;
		var dy = slingshotY - currentBird.y;
		currentBird.vx = dx * 0.18;
		currentBird.vy = dy * 0.18;
		currentBird.launched = true;
		launching = true;
		// Animate slingshot back
		tween(currentBird, {
			x: currentBird.x,
			y: currentBird.y
		}, {
			duration: 80
		});
	}
};
// --- Main Game Loop ---
game.update = function () {
	// Update all birds
	for (var i = 0; i < birds.length; i++) {
		birds[i].update();
	}
	// Update all pigs
	for (var i = 0; i < pigs.length; i++) {
		pigs[i].update();
	}
	// Update all blocks
	for (var i = 0; i < blocks.length; i++) {
		blocks[i].update();
	}
	// Bird-block collision
	for (var i = 0; i < birds.length; i++) {
		var bird = birds[i];
		if (!bird.launched) continue;
		if (bird.stopped) continue;
		// Collide with blocks
		for (var j = 0; j < blocks.length; j++) {
			var block = blocks[j];
			if (block.stopped) continue;
			if (block.intersectsCircle(bird)) {
				// Simple response: knock block, slow bird
				var angle = getAngle(bird.x, bird.y, block.x, block.y);
				var force = Math.sqrt(bird.vx * bird.vx + bird.vy * bird.vy) * 0.5;
				block.vx += Math.cos(angle) * force * 0.7;
				block.vy += Math.sin(angle) * force * 0.7;
				bird.vx *= 0.6;
				bird.vy *= 0.6;
			}
		}
	}
	// Bird-pig collision
	for (var i = 0; i < birds.length; i++) {
		var bird = birds[i];
		if (!bird.launched) continue;
		if (bird.stopped) continue;
		for (var j = 0; j < pigs.length; j++) {
			var pig = pigs[j];
			if (!pig.alive) continue;
			if (bird.intersectsCircle(pig)) {
				pig.alive = false;
				pig.visible = false;
				LK.setScore(LK.getScore() + 1000);
				scoreTxt.setText(LK.getScore());
			}
		}
	}
	// Block-pig collision (falling blocks can kill pigs)
	for (var i = 0; i < blocks.length; i++) {
		var block = blocks[i];
		if (block.stopped) continue;
		for (var j = 0; j < pigs.length; j++) {
			var pig = pigs[j];
			if (!pig.alive) continue;
			// Treat pig as circle, block as rectangle
			if (block.intersectsCircle(pig)) {
				pig.alive = false;
				pig.visible = false;
				LK.setScore(LK.getScore() + 1000);
				scoreTxt.setText(LK.getScore());
			}
		}
	}
	// Remove dead pigs
	var allPigsDead = true;
	for (var i = 0; i < pigs.length; i++) {
		if (pigs[i].alive) {
			allPigsDead = false;
			break;
		}
	}
	// If all pigs dead, win (only if there was at least one pig)
	if (pigs.length > 0 && allPigsDead) {
		LK.showYouWin();
		return;
	}
	// If current bird stopped, move to next bird
	if (currentBird && currentBird.launched && currentBird.stopped && !isDragging && launching) {
		birdIndex++;
		updateBirdsLeft();
		if (birdIndex < birds.length) {
			currentBird = birds[birdIndex];
			// Move next bird to slingshot
			tween(currentBird, {
				x: slingshotX,
				y: slingshotY
			}, {
				duration: 300,
				easing: tween.easeOut,
				onFinish: function onFinish() {
					launching = false;
				}
			});
		} else {
			// Out of birds, game over
			LK.showGameOver();
			return;
		}
		launching = false;
	}
};
// --- Start Game ---
setupLevel();

===================================================================
--- original.js
+++ change.js
@@ -284,9 +284,9 @@
 		birds.push(bird);
 		game.addChild(bird);
 	}
 	currentBird = birds[birdIndex];
-	// Place blocks (simple structure)
+	// Place blocks (simple structure, now using Block class with physics)
 	var block1 = new Block();
 	block1.x = 1500;
 	block1.y = groundY - 100;
 	blocks.push(block1);