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

/**** 
* Classes
****/ 
// Enemy class
var Enemy = Container.expand(function () {
	var self = Container.call(this);
	var sprite = self.attachAsset('enemy', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	// Reduce initial power and scaling of enemies (so a tower can kill in two hits at the beginning)
	self.maxHp = 4 + waveNumber * 2;
	self.hp = self.maxHp;
	self.speed = 3 + 0.35 * waveNumber;
	self.pathIndex = 0;
	self.progress = 0; // 0-1 between path points
	// For hit flash
	self.flash = function () {
		tween(sprite, {
			tint: 0xFFFFFF
		}, {
			duration: 60,
			onFinish: function onFinish() {
				tween(sprite, {
					tint: 0xB22222
				}, {
					duration: 120
				});
			}
		});
	};
	// Called every tick
	self.update = function () {
		// Move along path
		if (self.pathIndex < pathPoints.length - 1) {
			var p0 = pathPoints[self.pathIndex];
			var p1 = pathPoints[self.pathIndex + 1];
			var dx = p1.x - p0.x;
			var dy = p1.y - p0.y;
			var dist = Math.sqrt(dx * dx + dy * dy);
			var step = self.speed;
			var move = step / dist;
			self.progress += move;
			if (self.progress >= 1) {
				self.pathIndex += 1;
				self.progress = 0;
				if (self.pathIndex >= pathPoints.length - 1) {
					// Reached end
					self.x = p1.x;
					self.y = p1.y;
					self.reachedEnd = true;
					return;
				}
			}
			var px = p0.x + dx * self.progress;
			var py = p0.y + dy * self.progress;
			self.x = px;
			self.y = py;
		}
	};
	return self;
});
// Projectile class
var Projectile = Container.expand(function (x, y, angle, damage) {
	var self = Container.call(this);
	var sprite = self.attachAsset('projectile', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.x = x;
	self.y = y;
	self.angle = angle;
	self.speed = 18;
	self.damage = damage;
	self.radius = 15;
	// Called every tick
	self.update = function () {
		self.x += Math.cos(self.angle) * self.speed;
		self.y += Math.sin(self.angle) * self.speed;
	};
	return self;
});
// Tower class
var Tower = Container.expand(function () {
	var self = Container.call(this);
	// Attach base
	var base = self.attachAsset('towerBase', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	// Attach cannon
	var cannon = self.attachAsset('towerCannon', {
		anchorX: 0.5,
		anchorY: 0.8,
		y: -20
	});
	// Range indicator (hidden by default)
	var rangeCircle = self.attachAsset('towerRange', {
		anchorX: 0.5,
		anchorY: 0.5,
		alpha: 0
	});
	// Tower stats
	self.range = 280; // Increased from 200
	self.fireRate = 40; // Faster fire rate (was 60)
	self.cooldown = 0;
	self.level = 1;
	self.damage = 2; // Increased from 1
	self.upgradeCost = 50;
	// For upgrade UI
	self.showRange = function (show) {
		rangeCircle.alpha = show ? 0.2 : 0;
	};
	// Upgrade tower
	self.upgrade = function () {
		if (gold >= 50) {
			gold -= 50;
			self.level += 1;
			self.range += 40;
			self.damage += 1;
			self.fireRate = Math.max(30, self.fireRate - 10);
			self.upgradeCost += 50;
			updateGoldText();
			// Animate upgrade
			tween(self, {
				scaleX: 1.2,
				scaleY: 1.2
			}, {
				duration: 120,
				easing: tween.easeOut,
				onFinish: function onFinish() {
					tween(self, {
						scaleX: 1,
						scaleY: 1
					}, {
						duration: 120,
						easing: tween.easeIn
					});
				}
			});
		}
	};
	// Find nearest enemy in range
	self.findTarget = function () {
		var minDist = self.range;
		var target = null;
		for (var i = 0; i < enemies.length; ++i) {
			var e = enemies[i];
			var dx = e.x - self.x;
			var dy = e.y - self.y;
			var dist = Math.sqrt(dx * dx + dy * dy);
			if (dist < minDist) {
				minDist = dist;
				target = e;
			}
		}
		return target;
	};
	// Called every tick
	self.update = function () {
		if (self.cooldown > 0) {
			self.cooldown -= 1;
		}
		var target = self.findTarget();
		if (target) {
			// Rotate cannon towards target
			var dx = target.x - self.x;
			var dy = target.y - self.y;
			var angle = Math.atan2(dy, dx);
			cannon.rotation = angle - Math.PI / 2;
			// Fire if ready
			if (self.cooldown <= 0) {
				self.cooldown = self.fireRate;
				var proj = new Projectile(self.x, self.y, angle, self.damage);
				projectiles.push(proj);
				game.addChild(proj);
				// LK.getSound('shoot').play();
			}
		}
	};
	return self;
});

/**** 
* Initialize Game
****/ 
var game = new LK.Game({
	backgroundColor: 0x2e2b1b
});

/**** 
* Game Code
****/ 
// LK.init.sound('enemyDie', {volume:0.5});
// LK.init.sound('shoot', {volume:0.5});
// Sounds (not used in MVP, but ready for future)
// Path
// Projectiles
// Enemies
// For debug/upgrade, alpha set in code
// Towers
// Path definition (array of points)
var pathPoints = [{
	x: 200,
	y: 400
}, {
	x: 200,
	y: 1800
}, {
	x: 1000,
	y: 1800
}, {
	x: 1000,
	y: 600
}, {
	x: 1800,
	y: 600
}, {
	x: 1800,
	y: 2300
}];
// Gold, wave, etc.
var gold = 100;
var waveNumber = 1;
var enemies = [];
var towers = [];
var projectiles = [];
var lives = 10;
var enemiesToSpawn = 0;
var spawnTick = 0;
var waveInProgress = false;
// GUI: Gold display
var goldText = new Text2('Gold: 100', {
	size: 90,
	fill: 0xFFD700
});
goldText.anchor.set(1, 0); // Top right
LK.gui.topRight.addChild(goldText);
function updateGoldText() {
	goldText.setText('Gold: ' + gold);
}
// GUI: Wave display
var waveText = new Text2('Wave: 1', {
	size: 70,
	fill: 0xFFFFFF
});
waveText.anchor.set(0.5, 0);
LK.gui.top.addChild(waveText);
function updateWaveText() {
	waveText.setText('Wave: ' + waveNumber);
}
// GUI: Lives display
var livesText = new Text2('Lives: 10', {
	size: 70,
	fill: 0xFF4444
});
livesText.anchor.set(0, 0);
LK.gui.top.addChild(livesText);
function updateLivesText() {
	livesText.setText('Lives: ' + lives);
}
// Draw path tiles
for (var i = 0; i < pathPoints.length - 1; ++i) {
	var p0 = pathPoints[i];
	var p1 = pathPoints[i + 1];
	var dx = p1.x - p0.x;
	var dy = p1.y - p0.y;
	var dist = Math.sqrt(dx * dx + dy * dy);
	var steps = Math.floor(dist / 100);
	for (var s = 0; s <= steps; ++s) {
		var px = p0.x + dx * (s / steps);
		var py = p0.y + dy * (s / steps);
		var tile = LK.getAsset('pathTile', {
			anchorX: 0.5,
			anchorY: 0.5,
			x: px,
			y: py
		});
		game.addChild(tile);
	}
}
// Tower placement
var placingTower = false;
var towerGhost = null;
var towerCost = 50;
// Placeable area: not on path, not too close to other towers, not in top left 100x100
function canPlaceTower(x, y) {
	// Not in top left 100x100
	if (x < 100 && y < 100) return false;
	// Not too close to path
	for (var i = 0; i < pathPoints.length - 1; ++i) {
		var p0 = pathPoints[i];
		var p1 = pathPoints[i + 1];
		var dx = p1.x - p0.x;
		var dy = p1.y - p0.y;
		var dist = Math.sqrt(dx * dx + dy * dy);
		var steps = Math.floor(dist / 40);
		for (var s = 0; s <= steps; ++s) {
			var px = p0.x + dx * (s / steps);
			var py = p0.y + dy * (s / steps);
			var d = Math.sqrt((x - px) * (x - px) + (y - py) * (y - py));
			if (d < 100) return false;
		}
	}
	// Not too close to other towers
	for (var t = 0; t < towers.length; ++t) {
		var tw = towers[t];
		var d = Math.sqrt((x - tw.x) * (x - tw.x) + (y - tw.y) * (y - tw.y));
		if (d < 180) return false;
	}
	return true;
}
// Tower upgrade UI
var upgradeBtn = new Text2('Upgrade\n(50)', {
	size: 70,
	fill: 0x44BB44
});
upgradeBtn.anchor.set(0.5, 1);
// Not added to GUI yet; will be added near selected tower
var selectedTower = null;
// Handle upgrade button
upgradeBtn.down = function (x, y, obj) {
	if (selectedTower) {
		selectedTower.upgrade();
		// Update upgrade button cost
		upgradeBtn.setText('Upgrade\n(' + selectedTower.upgradeCost + ')');
	}
};
// Handle game touch events
game.down = function (x, y, obj) {
	// If placing tower
	if (placingTower) {
		if (canPlaceTower(x, y) && gold >= towerCost) {
			var t = new Tower();
			t.x = x;
			t.y = y;
			towers.push(t);
			game.addChild(t);
			gold -= towerCost;
			updateGoldText();
			placingTower = false;
			if (towerGhost) {
				towerGhost.destroy();
				towerGhost = null;
			}
		}
		return;
	}
	// Allow tower placement by clicking anywhere on the roadside (not on path, not in top left 100x100)
	if (!placingTower && gold >= towerCost) {
		if (canPlaceTower(x, y)) {
			var t = new Tower();
			t.x = x;
			t.y = y;
			towers.push(t);
			game.addChild(t);
			gold -= towerCost;
			updateGoldText();
			if (towerGhost) {
				towerGhost.destroy();
				towerGhost = null;
			}
			placingTower = false;
			return;
		}
	}
	// If clicking on a tower, select it or upgrade on double click
	var found = null;
	for (var i = 0; i < towers.length; ++i) {
		var tw = towers[i];
		var dx = x - tw.x;
		var dy = y - tw.y;
		if (Math.abs(dx) < 60 && Math.abs(dy) < 60) {
			found = tw;
			break;
		}
	}
	if (found) {
		// Double click detection for upgrade
		if (!found._lastClickTime) found._lastClickTime = 0;
		var now = Date.now();
		if (now - found._lastClickTime < 400) {
			// Double click detected, upgrade tower
			found.upgrade();
			// Update upgrade button cost if visible
			if (upgradeBtn.parent && selectedTower === found) {
				upgradeBtn.setText('Upgrade\n(' + found.upgradeCost + ')');
			}
			found._lastClickTime = 0;
			return;
		} else {
			found._lastClickTime = now;
		}
		if (selectedTower && selectedTower !== found) {
			selectedTower.showRange(false);
		}
		selectedTower = found;
		selectedTower.showRange(true);
		// Show upgrade button near tower (above)
		upgradeBtn.setText('Upgrade\n(' + selectedTower.upgradeCost + ')');
		LK.gui.bottom.addChild(upgradeBtn);
		return;
	}
	// Deselect tower if clicking elsewhere
	if (selectedTower) {
		selectedTower.showRange(false);
		selectedTower = null;
		if (upgradeBtn.parent) upgradeBtn.parent.removeChild(upgradeBtn);
	}
};
// Move handler for tower ghost
game.move = function (x, y, obj) {
	if (placingTower && towerGhost) {
		towerGhost.x = x;
		towerGhost.y = y;
		if (canPlaceTower(x, y) && gold >= towerCost) {
			towerGhost.alpha = 0.5;
		} else {
			towerGhost.alpha = 0.2;
		}
	}
};
// Remove ghost on up
game.up = function (x, y, obj) {
	if (placingTower && towerGhost) {
		if (towerGhost.parent) {
			towerGhost.parent.removeChild(towerGhost);
		}
		towerGhost = null;
		placingTower = false;
	}
};
// Start wave button (bottom center)
var startBtn = new Text2('Start Wave', {
	size: 90,
	fill: 0x44AAFF
});
startBtn.anchor.set(0.5, 1);
LK.gui.bottom.addChild(startBtn);
startBtn.down = function (x, y, obj) {
	if (!waveInProgress) {
		startWave();
	}
};
// Start a new wave
function startWave() {
	waveInProgress = true;
	enemiesToSpawn = 10 + (waveNumber - 1) * 2;
	spawnTick = 0;
	updateWaveText();
}
// Main update loop
game.update = function () {
	// Spawn enemies
	if (waveInProgress && enemiesToSpawn > 0) {
		if (LK.ticks % 30 === 0) {
			var e = new Enemy();
			var p = pathPoints[0];
			e.x = p.x;
			e.y = p.y;
			enemies.push(e);
			game.addChild(e);
			enemiesToSpawn -= 1;
		}
	}
	// Update enemies
	for (var i = enemies.length - 1; i >= 0; --i) {
		var e = enemies[i];
		e.update();
		// Check if reached end
		if (e.reachedEnd) {
			lives -= 1;
			updateLivesText();
			e.destroy();
			enemies.splice(i, 1);
			if (lives <= 0) {
				LK.effects.flashScreen(0xff0000, 1000);
				LK.showGameOver();
				return;
			}
			continue;
		}
	}
	// Update towers
	for (var i = 0; i < towers.length; ++i) {
		towers[i].update();
	}
	// Update projectiles
	for (var i = projectiles.length - 1; i >= 0; --i) {
		var p = projectiles[i];
		p.update();
		// Remove if out of bounds
		if (p.x < 0 || p.x > 2048 || p.y < 0 || p.y > 2732) {
			p.destroy();
			projectiles.splice(i, 1);
			continue;
		}
		// Check collision with enemies
		var hit = false;
		for (var j = enemies.length - 1; j >= 0; --j) {
			var e = enemies[j];
			var dx = p.x - e.x;
			var dy = p.y - e.y;
			var dist = Math.sqrt(dx * dx + dy * dy);
			if (dist < 50) {
				e.hp -= p.damage;
				e.flash();
				if (e.hp <= 0) {
					// Enemy dies
					gold += 10;
					updateGoldText();
					// LK.getSound('enemyDie').play();
					e.destroy();
					enemies.splice(j, 1);
				}
				p.destroy();
				projectiles.splice(i, 1);
				hit = true;
				break;
			}
		}
		if (hit) continue;
	}
	// Check if wave is over
	if (waveInProgress && enemiesToSpawn === 0 && enemies.length === 0) {
		waveInProgress = false;
		waveNumber += 1;
		updateWaveText();
		// Win condition: survive 10 waves
		if (waveNumber > 10) {
			LK.effects.flashScreen(0x44ff44, 1000);
			LK.showYouWin();
			return;
		}
		// Automatically start next wave after a short delay (e.g. 2 seconds)
		LK.setTimeout(function () {
			if (!waveInProgress && lives > 0 && waveNumber <= 10) {
				startWave();
			}
		}, 2000);
	}
};

===================================================================
--- original.js
+++ change.js
@@ -350,12 +350,11 @@
 			}
 		}
 		return;
 	}
-	// Allow tower placement by clicking anywhere on the side of the screen (not on path, not in top left 100x100)
+	// Allow tower placement by clicking anywhere on the roadside (not on path, not in top left 100x100)
 	if (!placingTower && gold >= towerCost) {
-		// Left side (x < 400) or right side (x > 1648)
-		if ((x < 400 || x > 1648) && canPlaceTower(x, y)) {
+		if (canPlaceTower(x, y)) {
 			var t = new Tower();
 			t.x = x;
 			t.y = y;
 			towers.push(t);