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

/**** 
* Classes
****/ 
// Bird class
var Bird = Container.expand(function () {
	var self = Container.call(this);
	// Attach a yellow ellipse as the bird
	var birdAsset = self.attachAsset('bird', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	// Bird physics
	self.velocityY = 0;
	self.gravity = 1.2; // Gravity per frame
	self.flapStrength = -28; // Negative for upward movement
	// Bird size for collision
	self.radius = birdAsset.width * 0.45;
	// Flap method
	self.flap = function () {
		self.velocityY = self.flapStrength;
		// Animate a quick upward tilt
		tween(self, {
			rotation: -0.3
		}, {
			duration: 80,
			easing: tween.cubicOut,
			onFinish: function onFinish() {
				// Return to downward tilt
				tween(self, {
					rotation: 0.4
				}, {
					duration: 300,
					easing: tween.cubicIn
				});
			}
		});
	};
	// Update method
	self.update = function () {
		self.velocityY += self.gravity;
		self.y += self.velocityY;
		// Clamp rotation based on velocity
		if (self.velocityY > 0) {
			self.rotation = 0.4;
		} else if (self.velocityY < 0) {
			self.rotation = -0.3;
		}
	};
	return self;
});
// PipePair class (top and bottom pipes)
var PipePair = Container.expand(function () {
	var self = Container.call(this);
	// Pipe config
	self.pipeWidth = 220;
	self.gapHeight = 520;
	self.speed = 7;
	// Randomize gap position
	var minGapY = 400;
	var maxGapY = 2732 - 400 - self.gapHeight;
	self.gapY = minGapY + Math.floor(Math.random() * (maxGapY - minGapY));
	// Top pipe
	var topPipe = self.attachAsset('pipe', {
		anchorX: 0,
		anchorY: 1,
		width: self.pipeWidth,
		height: self.gapY,
		color: 0x3bb54a,
		shape: 'box',
		x: 0,
		y: self.gapY
	});
	// Bottom pipe
	var bottomPipe = self.attachAsset('pipe', {
		anchorX: 0,
		anchorY: 0,
		width: self.pipeWidth,
		height: 2732 - (self.gapY + self.gapHeight),
		color: 0x3bb54a,
		shape: 'box',
		x: 0,
		y: self.gapY + self.gapHeight
	});
	// For collision
	self.topPipe = topPipe;
	self.bottomPipe = bottomPipe;
	// Scoring flag
	self.passed = false;
	// Update method
	self.update = function () {
		self.x -= self.speed;
	};
	// Collision check with bird
	self.collidesWith = function (bird) {
		// Bird bounding box
		var bx = bird.x;
		var by = bird.y;
		var br = bird.radius;
		// Top pipe rect
		var tx = self.x;
		var ty = 0;
		var tw = self.pipeWidth;
		var th = self.gapY;
		// Bottom pipe rect
		var bx2 = self.x;
		var by2 = self.gapY + self.gapHeight;
		var bw2 = self.pipeWidth;
		var bh2 = 2732 - by2;
		// Circle-rectangle collision
		function circleRectCollide(cx, cy, cr, rx, ry, rw, rh) {
			var closestX = Math.max(rx, Math.min(cx, rx + rw));
			var closestY = Math.max(ry, Math.min(cy, ry + rh));
			var dx = cx - closestX;
			var dy = cy - closestY;
			return dx * dx + dy * dy < cr * cr;
		}
		if (circleRectCollide(bx, by, br, tx, ty, tw, th)) return true;
		if (circleRectCollide(bx, by, br, bx2, by2, bw2, bh2)) return true;
		return false;
	};
	return self;
});

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

/**** 
* Game Code
****/ 
// Game constants
var BIRD_START_X = 600;
var BIRD_START_Y = 1200;
var PIPE_INTERVAL = 90; // Frames between pipes
var GROUND_HEIGHT = 180;
// Create bird asset (ellipse)
// Create pipe asset (box)
// Ground asset (for collision)
// Score text
var scoreTxt = new Text2('0', {
	size: 180,
	fill: 0xFFFFFF
});
scoreTxt.anchor.set(0.5, 0);
LK.gui.top.addChild(scoreTxt);
// Bird instance
var bird = new Bird();
game.addChild(bird);
bird.x = BIRD_START_X;
bird.y = BIRD_START_Y;
// Ground instance
var ground = LK.getAsset('ground', {
	anchorX: 0,
	anchorY: 0,
	x: 0,
	y: 2732 - GROUND_HEIGHT
});
game.addChild(ground);
// Pipes array
var pipes = [];
// Game state
var gameStarted = false;
var gameOver = false;
var frameCount = 0;
// For tap/flap
game.down = function (x, y, obj) {
	if (gameOver) return;
	if (!gameStarted) {
		gameStarted = true;
	}
	bird.flap();
};
// Main update loop
game.update = function () {
	if (gameOver) return;
	if (gameStarted) {
		bird.update();
		// Add new pipes
		if (frameCount % PIPE_INTERVAL === 0) {
			var pipePair = new PipePair();
			pipePair.x = 2048;
			game.addChild(pipePair);
			pipes.push(pipePair);
		}
		// Update pipes and check for collisions
		for (var i = pipes.length - 1; i >= 0; i--) {
			var pipe = pipes[i];
			pipe.update();
			// Collision
			if (pipe.collidesWith(bird)) {
				endGame();
				return;
			}
			// Score: when bird passes the pipe
			if (!pipe.passed && pipe.x + pipe.pipeWidth < bird.x) {
				pipe.passed = true;
				LK.setScore(LK.getScore() + 1);
				scoreTxt.setText(LK.getScore());
			}
			// Remove off-screen pipes
			if (pipe.x + pipe.pipeWidth < 0) {
				pipe.destroy();
				pipes.splice(i, 1);
			}
		}
		// Ground collision
		if (bird.y + bird.radius > 2732 - GROUND_HEIGHT) {
			bird.y = 2732 - GROUND_HEIGHT - bird.radius;
			endGame();
			return;
		}
		// Ceiling clamp
		if (bird.y - bird.radius < 0) {
			bird.y = bird.radius;
			bird.velocityY = 0;
		}
		frameCount++;
	} else {
		// Idle bird bobbing
		bird.y = BIRD_START_Y + Math.sin(LK.ticks / 20) * 30;
	}
};
// End game function
function endGame() {
	if (gameOver) return;
	gameOver = true;
	// Flash red
	LK.effects.flashScreen(0xff0000, 600);
	// Show game over popup
	LK.showGameOver();
}
// Reset on game restart
game.on('destroy', function () {
	// Clean up
	for (var i = 0; i < pipes.length; i++) {
		pipes[i].destroy();
	}
	pipes = [];
	gameStarted = false;
	gameOver = false;
	frameCount = 0;
	LK.setScore(0);
	scoreTxt.setText('0');
	bird.x = BIRD_START_X;
	bird.y = BIRD_START_Y;
	bird.velocityY = 0;
	bird.rotation = 0;
});