/**** 
* Classes
****/ 
// Enemy class
// Bullet class
var Bullet = Container.expand(function (startX, startY, targetEnemy, damage, speed) {
	var self = Container.call(this);
	// Bullet properties
	self.targetEnemy = targetEnemy;
	self.damage = damage || 10;
	self.speed = speed || 5;
	self.x = startX;
	self.y = startY;
	// Visual representation of bullet
	var bulletGraphics = self.attachAsset('bullet', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	// Update method - called every frame
	self.update = function () {
		// If target is gone, destroy this bullet
		if (!self.targetEnemy || !self.targetEnemy.parent) {
			self.destroy();
			return;
		}
		// Move toward target
		var dx = self.targetEnemy.x - self.x;
		var dy = self.targetEnemy.y - self.y;
		var distance = Math.sqrt(dx * dx + dy * dy);
		// If we hit the target
		if (distance < self.speed) {
			// Deal damage to enemy
			self.targetEnemy.health -= self.damage;
			// Update health bar visual
			if (self.targetEnemy.health <= 0) {
				// Enemy is defeated
				self.targetEnemy.health = 0;
			} else {
				// Update health bar width based on remaining health percentage
				self.targetEnemy.healthBar.width = self.targetEnemy.health / self.targetEnemy.maxHealth * 70;
			}
			// Remove this bullet
			self.destroy();
		} else {
			// Move toward target
			var angle = Math.atan2(dy, dx);
			self.x += Math.cos(angle) * self.speed;
			self.y += Math.sin(angle) * self.speed;
		}
	};
	return self;
});
// DebugCell class
var DebugCell = Container.expand(function () {
	var self = Container.call(this);
	var cellGraphics = self.attachAsset('cell', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	cellGraphics.tint = Math.random() * 0xffffff;
	// Add a debug arrow to the debug cells
	var debugArrows = [];
	// Add a number label to the debug cells
	var numberLabel = new Text2('0', {
		size: 30,
		fill: 0xFFFFFF,
		weight: 800
	});
	numberLabel.anchor.set(.5, .5);
	self.addChild(numberLabel);
	self.update = function () {};
	self.down = function () {
		return;
		if (self.cell.type == 0 || self.cell.type == 1) {
			self.cell.type = self.cell.type == 1 ? 0 : 1;
			if (grid.pathFind()) {
				self.cell.type = self.cell.type == 1 ? 0 : 1;
				grid.pathFind();
				var notification = game.addChild(new Notification("Path is blocked!"));
				notification.x = 2048 / 2;
				notification.y = grid.height - 50;
			}
			grid.renderDebug();
		}
	};
	self.removeArrows = function () {
		while (debugArrows.length) {
			self.removeChild(debugArrows.pop());
		}
	};
	self.render = function (data) {
		switch (data.type) {
			case 0:
			case 2:
				{
					if (data.pathId != pathId) {
						self.removeArrows();
						numberLabel.setText("-");
						cellGraphics.tint = 0x880000;
						return;
					}
					numberLabel.visible = true;
					var tint = Math.floor(data.score / maxScore * 0x88);
					cellGraphics.tint = 0x88 - tint << 8 | tint;
					while (debugArrows.length > data.targets.length) {
						self.removeChild(debugArrows.pop());
					}
					for (var a = 0; a < data.targets.length; a++) {
						var destination = data.targets[a];
						var ox = destination.x - data.x;
						var oy = destination.y - data.y;
						var angle = Math.atan2(oy, ox);
						if (!debugArrows[a]) {
							debugArrows[a] = LK.getAsset('arrow', {
								anchorX: -.5,
								anchorY: 0.5
							});
							debugArrows[a].alpha = .5;
							self.addChildAt(debugArrows[a], 1);
							//							debugArrows = 
						}
						debugArrows[a].rotation = angle;
						//	debugArrow.rotation = angle;
					}
					break;
				}
			case 1:
				{
					self.removeArrows();
					cellGraphics.tint = 0xaaaaaa;
					numberLabel.visible = false;
					break;
				}
			case 3:
				{
					self.removeArrows();
					cellGraphics.tint = 0x008800;
					numberLabel.visible = false;
					break;
				}
		}
		numberLabel.setText(Math.floor(data.score / 1000) / 10);
	};
});
var Enemy = Container.expand(function () {
	var self = Container.call(this);
	var enemyGraphics = self.attachAsset('enemy', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.speed = .05;
	self.cellX = 0;
	self.cellY = 0;
	self.currentCellX = 0;
	self.currentCellY = 0;
	self.currentTarget = undefined;
	self.maxHealth = 100; // Starting max health
	self.health = self.maxHealth; // Current health
	self.bulletsTargetingThis = []; // Track bullets targeting this enemy
	// Add health bar to the enemy
	var healthBarOutline = self.attachAsset('healthBarOutline', {
		anchorX: 0,
		anchorY: 0.5
	});
	var healthBarBG = self.attachAsset('healthBar', {
		anchorX: 0,
		anchorY: 0.5
	});
	var healthBar = self.attachAsset('healthBar', {
		anchorX: 0,
		anchorY: 0.5
	});
	healthBarBG.y = healthBarOutline.y = healthBar.y = -enemyGraphics.height / 2 - 10; // Position the health bar above the enemy
	healthBarOutline.x = -healthBarOutline.width / 2;
	healthBarBG.x = healthBar.x = -healthBar.width / 2;
	healthBar.tint = 0x00ff00;
	healthBarBG.tint = 0xff0000;
	self.healthBar = healthBar;
});
//Class for the gr0x412e2eles all logic related to grid movement and interaction
var Grid = Container.expand(function (gridWidth, gridHeight) {
	var self = Container.call(this);
	self.cells = [];
	self.spawns = [];
	self.goals = [];
	for (var i = 0; i < gridWidth; i++) {
		self.cells[i] = [];
		for (var j = 0; j < gridHeight; j++) {
			self.cells[i][j] = {
				score: 0,
				pathId: 0,
				towersInRange: [] // Cache for towers in range
			};
		}
	}
	/*
				Cell Types
				0: Transparent floor
				1: Wall
				2: Spawn
				3: Goal
	*/
	for (var i = 0; i < gridWidth; i++) {
		for (var j = 0; j < gridHeight; j++) {
			// Set the type to 1 (wall) if the cell is on the edge of the grid, otherwise set it to 0 (ground)
			var cell = self.cells[i][j];
			var cellType = i === 0 || i === gridWidth - 1 || j <= 4 || j >= gridHeight - 4 ? 1 : 0;
			if (i > 11 - 3 && i <= 11 + 3) {
				if (j === 0) {
					cellType = 2;
					self.spawns.push(cell);
				} else if (j <= 4) {
					cellType = 0;
				} else if (j === gridHeight - 1) {
					cellType = 3;
					self.goals.push(cell);
				} else if (j >= gridHeight - 4) {
					cellType = 0;
				}
			}
			cell.type = cellType;
			cell.x = i;
			cell.y = j;
			/*if (cell.type == 0) {
				if (Math.random() > .5) {
					cell.type = 1;
				}
			}*/
			//Cache neighbours for speed
			cell.upLeft = self.cells[i - 1] && self.cells[i - 1][j - 1];
			cell.up = self.cells[i - 1] && self.cells[i - 1][j];
			cell.upRight = self.cells[i - 1] && self.cells[i - 1][j + 1];
			cell.left = self.cells[i][j - 1];
			cell.right = self.cells[i][j + 1];
			cell.downLeft = self.cells[i + 1] && self.cells[i + 1][j - 1];
			cell.down = self.cells[i + 1] && self.cells[i + 1][j];
			cell.downRight = self.cells[i + 1] && self.cells[i + 1][j + 1];
			cell.neighbors = [cell.upLeft, cell.up, cell.upRight, cell.right, cell.downRight, cell.down, cell.downLeft, cell.left];
			cell.targets = [];
			if (j > 3 && j <= gridHeight - 4) {
				var debugCell = new DebugCell();
				self.addChild(debugCell);
				debugCell.cell = cell;
				debugCell.x = i * CELL_SIZE;
				debugCell.y = j * CELL_SIZE;
				cell.debugCell = debugCell;
			}
		}
	}
	self.getCell = function (x, y) {
		return self.cells[x] && self.cells[x][y];
	};
	self.pathFind = function () {
		var before = new Date().getTime();
		var toProcess = self.goals.concat([]);
		maxScore = 0;
		pathId += 1;
		for (var a = 0; a < toProcess.length; a++) {
			toProcess[a].pathId = pathId;
		}
		function processNode(node, targetValue, targetNode) {
			if (node && node.type != 1) {
				if (node.pathId < pathId || targetValue < node.score) {
					node.targets = [targetNode];
				} else if (node.pathId == pathId && targetValue == node.score) {
					node.targets.push(targetNode);
				}
				if (node.pathId < pathId || targetValue < node.score) {
					node.score = targetValue;
					if (node.pathId != pathId) {
						toProcess.push(node);
					}
					node.pathId = pathId;
					if (targetValue > maxScore) {
						maxScore = targetValue;
					}
				}
			}
		}
		while (toProcess.length) {
			var nodes = toProcess;
			toProcess = [];
			for (var a = 0; a < nodes.length; a++) {
				var node = nodes[a];
				var targetScore = node.score + 14142;
				// Check for diagonal movement and ensure both adjacent cells are not walls
				if (node.up && node.left && node.up.type != 1 && node.left.type != 1) {
					processNode(node.upLeft, targetScore, node);
				}
				if (node.up && node.right && node.up.type != 1 && node.right.type != 1) {
					processNode(node.upRight, targetScore, node);
				}
				if (node.down && node.right && node.down.type != 1 && node.right.type != 1) {
					processNode(node.downRight, targetScore, node);
				}
				if (node.down && node.left && node.down.type != 1 && node.left.type != 1) {
					processNode(node.downLeft, targetScore, node);
				}
				targetScore = node.score + 10000;
				processNode(node.up, targetScore, node);
				processNode(node.right, targetScore, node);
				processNode(node.down, targetScore, node);
				processNode(node.left, targetScore, node);
			}
		}
		for (var a = 0; a < self.spawns.length; a++) {
			if (self.spawns[a].pathId != pathId) {
				console.warn("Spawn blocked");
				return true;
			}
		}
		for (var a = 0; a < enemies.length; a++) {
			var enemy = enemies[a];
			var target = self.getCell(enemy.cellX, enemy.cellY);
			if (enemy.currentTarget) {
				if (enemy.currentTarget.pathId != pathId) {
					if (!target || target.pathId != pathId) {
						console.warn("Enemy blocked");
						return true;
					}
				}
			} else if (!target || target.pathId != pathId) {
				console.warn("Enemy blocked");
				return true;
			}
		}
		console.log("Speed", new Date().getTime() - before);
	};
	self.renderDebug = function () {
		for (var i = 0; i < gridWidth; i++) {
			for (var j = 0; j < gridHeight; j++) {
				var debugCell = self.cells[i][j].debugCell;
				if (debugCell) {
					debugCell.render(self.cells[i][j]);
				}
			}
		}
	};
	self.updateEnemy = function (enemy) {
		var cell = grid.getCell(enemy.cellX, enemy.cellY);
		if (cell.type == 3) {
			return true;
		}
		if (!enemy.currentTarget) {
			enemy.currentTarget = cell.targets[0];
		}
		if (enemy.currentTarget) {
			//Allows enemies to change direction right away.
			if (cell.score < enemy.currentTarget.score) {
				enemy.currentTarget = cell;
			}
			var ox = enemy.currentTarget.x - enemy.currentCellX;
			var oy = enemy.currentTarget.y - enemy.currentCellY;
			var dist = Math.sqrt(ox * ox + oy * oy);
			if (dist < enemy.speed) {
				enemy.cellX = Math.round(enemy.currentCellX);
				enemy.cellY = Math.round(enemy.currentCellY);
				enemy.currentTarget = undefined;
				return;
			}
			var angle = Math.atan2(oy, ox);
			enemy.currentCellX += Math.cos(angle) * enemy.speed;
			enemy.currentCellY += Math.sin(angle) * enemy.speed;
		}
		enemy.x = grid.x + enemy.currentCellX * CELL_SIZE;
		enemy.y = grid.y + enemy.currentCellY * CELL_SIZE;
	};
});
// Notification class
var Notification = Container.expand(function (message) {
	var self = Container.call(this);
	var notificationGraphics = self.attachAsset('notification', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	var notificationText = new Text2(message, {
		size: 50,
		fill: 0x000000,
		weight: 800
	});
	notificationText.anchor.set(0.5, 0.5);
	notificationGraphics.width = notificationText.width + 30;
	self.addChild(notificationText);
	self.alpha = 1;
	var fadeOutTime = 120; // 2 seconds at 60FPS
	self.update = function () {
		if (fadeOutTime > 0) {
			fadeOutTime--;
			self.alpha = Math.min(fadeOutTime / 120 * 2, 1);
		} else {
			self.destroy();
		}
	};
	return self;
});
// Tower class that can be placed on the grid
var Tower = Container.expand(function (id) {
	var self = Container.call(this);
	// Tower attributes
	self.id = id || 'default';
	self.level = 1;
	self.maxLevel = 6;
	self.gridX = 0;
	self.gridY = 0;
	self.range = 3 * CELL_SIZE; // initial range (3 grid cells)
	self.cellsInRange = []; // Cache for cells in range
	self.fireRate = 60; // frames between shots
	self.bulletSpeed = 5;
	self.damage = 10;
	self.lastFired = 0;
	self.targetEnemy = null;
	// Create the tower base (a square)
	var baseGraphics = self.attachAsset('tower', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	// Level indicators (dots at bottom of tower)
	var levelIndicators = [];
	var maxDots = self.maxLevel;
	var dotSpacing = baseGraphics.width / (maxDots + 1);
	var dotSize = CELL_SIZE / 6;
	for (var i = 0; i < maxDots; i++) {
		var dot = new Container();
		var towerLevelIndicator = dot.attachAsset('towerLevelIndicator', {
			anchorX: 0.5,
			anchorY: 0.5
		});
		towerLevelIndicator.width = dotSize;
		towerLevelIndicator.height = dotSize;
		towerLevelIndicator.tint = 0xCCCCCC; // Gray dots by default
		// Position dot at bottom of tower
		dot.x = -CELL_SIZE + dotSpacing * (i + 1);
		dot.y = CELL_SIZE * 0.7;
		self.addChild(dot);
		levelIndicators.push(dot);
	}
	// Create the gun turret that will rotate
	var gunContainer = new Container();
	self.addChild(gunContainer);
	var gunGraphics = gunContainer.attachAsset('defense', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	//gunGraphics.y = -CELL_SIZE * 0.3; // Position the gun slightly up from center
	// Update the level indicators
	self.updateLevelIndicators = function () {
		for (var i = 0; i < maxDots; i++) {
			var dot = levelIndicators[i];
			var towerLevelIndicator = dot.children[0];
			// Light up dots up to current level
			if (i < self.level) {
				towerLevelIndicator.alpha = 1; // Fully visible for active levels
			} else {
				towerLevelIndicator.alpha = 0.3; // Semi-transparent for inactive levels
			}
		}
	};
	// Initialize level indicators
	self.updateLevelIndicators();
	// Method to upgrade the tower
	self.upgrade = function () {
		if (self.level < self.maxLevel) {
			// Calculate upgrade cost based on level
			var upgradeCost = 10 + self.level * 5;
			// Check if player has enough gold
			if (gold >= upgradeCost) {
				gold -= upgradeCost;
				self.level++;
				// Increase stats based on level
				self.range = (3 + self.level * 0.5) * CELL_SIZE;
				self.fireRate = Math.max(20, 60 - self.level * 8); // Faster firing rate
				self.damage = 10 + self.level * 5;
				self.bulletSpeed = 5 + self.level * 0.5;
				// Update level indicators
				self.updateLevelIndicators();
				// Update UI to reflect gold change
				updateUI();
				return true;
			} else {
				// Show notification for not enough gold
				var notification = game.addChild(new Notification("Not enough gold to upgrade!"));
				notification.x = 2048 / 2;
				notification.y = grid.height - 50;
				return false;
			}
		}
		return false;
	};
	// Method to find the nearest enemy within range
	self.findTarget = function () {
		var closestEnemy = null;
		var closestScore = Infinity; // Use pathfinding score to determine proximity to goal
		for (var i = 0; i < self.cellsInRange.length; i++) {
			var cell = self.cellsInRange[i];
			for (var j = 0; j < enemies.length; j++) {
				var enemy = enemies[j];
				if (enemy.cellX === cell.x && enemy.cellY === cell.y) {
					// Check if this enemy is closer to the goal based on pathfinding score
					if (cell.score < closestScore) {
						closestScore = cell.score;
						closestEnemy = enemy;
					}
				}
			}
		}
		// Reset targetEnemy if no valid target is found
		if (!closestEnemy) {
			self.targetEnemy = null;
		}
		return closestEnemy;
	};
	// Update method
	self.update = function () {
		// Always find the target every frame to ensure state consistency
		self.targetEnemy = self.findTarget();
		// Rotate gun toward target
		if (self.targetEnemy) {
			var dx = self.targetEnemy.x - self.x;
			var dy = self.targetEnemy.y - self.y;
			var angle = Math.atan2(dy, dx);
			// Rotate the gun container
			gunContainer.rotation = angle;
			// Fire at target if cooldown is complete
			if (LK.ticks - self.lastFired >= self.fireRate) {
				self.fire();
				self.lastFired = LK.ticks;
			}
		}
	};
	// Check if enemy is in range
	self.isInRange = function (enemy) {
		if (!enemy) {
			return false;
		}
		var dx = enemy.x - self.x;
		var dy = enemy.y - self.y;
		var distance = Math.sqrt(dx * dx + dy * dy);
		return distance <= self.range;
	};
	// Fire at the current target
	self.fire = function () {
		if (self.targetEnemy) {
			// Verify the target is alive and calculate damage including future damage
			var potentialDamage = 0;
			for (var i = 0; i < self.targetEnemy.bulletsTargetingThis.length; i++) {
				potentialDamage += self.targetEnemy.bulletsTargetingThis[i].damage;
			}
			// Only shoot if enemy would still be alive after all current bullets hit
			if (self.targetEnemy.health > potentialDamage) {
				// Calculate bullet starting position
				var bulletX = self.x + Math.cos(gunContainer.rotation) * 40;
				var bulletY = self.y + Math.sin(gunContainer.rotation) * 40;
				// Create a new bullet
				var bullet = new Bullet(bulletX, bulletY, self.targetEnemy, self.damage, self.bulletSpeed);
				game.addChild(bullet);
				// Add bullet to global bullets array and to enemy's tracking array
				bullets.push(bullet);
				self.targetEnemy.bulletsTargetingThis.push(bullet);
			}
		}
	};
	// Place tower on the grid
	self.placeOnGrid = function (gridX, gridY) {
		self.gridX = gridX;
		self.gridY = gridY;
		// Adjust by half a cell size to align with grid cell centers
		self.x = grid.x + gridX * CELL_SIZE + CELL_SIZE / 2;
		self.y = grid.y + gridY * CELL_SIZE + CELL_SIZE / 2;
		// Mark these grid cells as occupied
		for (var i = 0; i < 2; i++) {
			for (var j = 0; j < 2; j++) {
				var cell = grid.getCell(gridX + i, gridY + j);
				if (cell) {
					cell.type = 1; // Mark as wall/occupied
				}
			}
		}
		// Calculate cells in range
		self.cellsInRange = [];
		for (var i = -Math.floor(self.range / CELL_SIZE); i <= Math.floor(self.range / CELL_SIZE); i++) {
			for (var j = -Math.floor(self.range / CELL_SIZE); j <= Math.floor(self.range / CELL_SIZE); j++) {
				var cell = grid.getCell(gridX + i, gridY + j);
				if (cell) {
					self.cellsInRange.push(cell);
					cell.towersInRange.push(self);
				}
			}
		}
	};
	return self;
});
// TowerPreview class for showing where towers can be placed
var TowerPreview = Container.expand(function () {
	var self = Container.call(this);
	// Define tower range (in grid cells)
	var towerRange = 3;
	var rangeInPixels = towerRange * CELL_SIZE;
	// Create the range indicator (circle)
	var rangeIndicator = new Container();
	self.addChild(rangeIndicator);
	// Since we don't have direct access to Graphics,
	// we'll create a white semi-transparent circle shape asset
	var rangeGraphics = rangeIndicator.attachAsset('rangeCircle', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	rangeGraphics.alpha = 0.3; // Make it semi-transparent
	// Create the preview square (2x2 grid cells)
	var previewGraphics = self.attachAsset('towerpreview', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	// Set the size to cover 2x2 grid cells
	previewGraphics.width = CELL_SIZE * 2;
	previewGraphics.height = CELL_SIZE * 2;
	// Initial state
	self.canPlace = false;
	self.gridX = 0;
	self.gridY = 0;
	self.blockedByEnemy = false; // Track if placement is blocked by enemy
	// Update the preview color based on placement possibility
	self.updatePlacementStatus = function () {
		// First check if placement is valid from a grid perspective
		var validGridPlacement = true;
		// Check if we're in the valid placement area (main square of the board)
		if (self.gridY <= 4 || self.gridY + 1 >= grid.cells[0].length - 4) {
			validGridPlacement = false;
		} else {
			// Check each of the 2x2 cells
			for (var i = 0; i < 2; i++) {
				for (var j = 0; j < 2; j++) {
					var cell = grid.getCell(self.gridX + i, self.gridY + j);
					// Can't place if any cell is undefined or not of type 0 (empty ground)
					if (!cell || cell.type !== 0) {
						validGridPlacement = false;
						break;
					}
				}
				if (!validGridPlacement) {
					break;
				}
			}
		}
		// Now check if any enemy is occupying the space where the tower would be placed
		self.blockedByEnemy = false;
		if (validGridPlacement) {
			for (var i = 0; i < enemies.length; i++) {
				var enemy = enemies[i];
				if (enemy.cellX >= self.gridX && enemy.cellX < self.gridX + 2 && enemy.cellY >= self.gridY && enemy.cellY < self.gridY + 2) {
					self.blockedByEnemy = true;
					break;
				}
			}
		}
		// Set final placement status
		self.canPlace = validGridPlacement && !self.blockedByEnemy;
		// If we can place, tint green, otherwise red
		previewGraphics.tint = self.canPlace ? 0x00FF00 : 0xFF0000;
	};
	// Check if the tower can be placed at the current position
	self.checkPlacement = function () {
		self.updatePlacementStatus();
	};
	// Snap the preview to the grid
	self.snapToGrid = function (x, y) {
		// Convert screen coordinates to grid coordinates
		// Offset by the grid's position
		var gridPosX = x - grid.x;
		var gridPosY = y - grid.y;
		// Convert to grid coordinates and round down to get the top-left cell
		self.gridX = Math.floor(gridPosX / CELL_SIZE);
		self.gridY = Math.floor(gridPosY / CELL_SIZE);
		// Position the preview at the intersection of the four cells
		// Adding CELL_SIZE to gridX and gridY gives us the center point
		// Adjust by half a cell size to align with grid cell centers
		self.x = grid.x + self.gridX * CELL_SIZE + CELL_SIZE / 2; // Center of the 2x2 grid
		self.y = grid.y + self.gridY * CELL_SIZE + CELL_SIZE / 2; // Center of the 2x2 grid
		// Check if we can place the tower here
		self.checkPlacement();
	};
	return self;
});

/**** 
* Initialize Game
****/ 
var game = new LK.Game({
	backgroundColor: 0x333333 //Init game with black background 
});

/**** 
* Game Code
****/ 
// Define cell size as a global constant
var CELL_SIZE = 76;
var pathId = 1;
var maxScore = 0;
var enemies = [];
var towers = [];
var bullets = []; // Array to store active bullets
var defenses = [];
// Game resources and scores
var gold = 80;
var lives = 20;
var score = 0;
// Create UI elements for resources
var goldText = new Text2('Gold: ' + gold, {
	size: 40,
	fill: 0xFFD700,
	weight: 800
});
goldText.anchor.set(0.5, 0.5);
var livesText = new Text2('Lives: ' + lives, {
	size: 40,
	fill: 0x00FF00,
	weight: 800
});
livesText.anchor.set(0.5, 0.5);
var scoreText = new Text2('Score: ' + score, {
	size: 40,
	fill: 0xFF0000,
	weight: 800
});
scoreText.anchor.set(0.5, 0.5);
// Position UI elements at the top of the screen
// Avoid top left corner (pause button area)
// Center the UI elements with proper spacing
var topMargin = 60;
var centerX = 2048 / 2;
var spacing = 300; // Reduced spacing between elements
// Position the elements centered on the screen
// First, attach to the top center container
LK.gui.top.addChild(goldText);
LK.gui.top.addChild(livesText);
LK.gui.top.addChild(scoreText);
// Position lives text in the center
livesText.x = 0; // Center position (relative to top center)
livesText.y = topMargin;
// Position gold text to the left of lives
goldText.x = -spacing;
goldText.y = topMargin;
// Position score text to the right of lives
scoreText.x = spacing;
scoreText.y = topMargin;
// Helper function to update UI
function updateUI() {
	goldText.setText('Gold: ' + gold);
	livesText.setText('Lives: ' + lives);
	scoreText.setText('Score: ' + score);
}
// Create separate layers for debug tiles, towers, and enemies
var debugLayer = new Container();
var towerLayer = new Container();
var enemyLayer = new Container();
var grid = new Grid(24, 29 + 6);
grid.x = 150;
grid.y = 250 - CELL_SIZE * 4;
grid.pathFind();
grid.renderDebug();
debugLayer.addChild(grid);
// Add layers to the game in the correct order
game.addChild(debugLayer);
game.addChild(towerLayer);
game.addChild(enemyLayer);
var offset = 0;
// Create tower preview
var towerPreview = new TowerPreview();
game.addChild(towerPreview);
towerPreview.visible = false;
// Handle drag events for tower placement
var isDragging = false;
// Check if placing a tower would block the path
function wouldBlockPath(gridX, gridY) {
	// Temporarily mark cells as walls
	var cells = [];
	for (var i = 0; i < 2; i++) {
		for (var j = 0; j < 2; j++) {
			var cell = grid.getCell(gridX + i, gridY + j);
			if (cell) {
				cells.push({
					cell: cell,
					originalType: cell.type
				});
				cell.type = 1; // Mark as wall
			}
		}
	}
	// Check if path is still valid
	var blocked = grid.pathFind();
	// Restore original cell types
	for (var i = 0; i < cells.length; i++) {
		cells[i].cell.type = cells[i].originalType;
	}
	// Re-find path with original cells
	grid.pathFind();
	grid.renderDebug();
	return blocked;
}
// Place a tower at the grid position
function placeTower(gridX, gridY) {
	// Tower cost
	var towerCost = 5;
	// Check if player has enough gold
	if (gold >= towerCost) {
		var tower = new Tower('default');
		tower.placeOnGrid(gridX, gridY);
		towerLayer.addChild(tower);
		towers.push(tower);
		// Deduct gold
		gold -= towerCost;
		updateUI();
		// Update grid pathing
		grid.pathFind();
		grid.renderDebug();
		return true;
	} else {
		// Not enough gold
		var notification = game.addChild(new Notification("Not enough gold!"));
		notification.x = 2048 / 2;
		notification.y = grid.height - 50;
		return false;
	}
}
game.down = function (x, y, obj) {
	// Check if clicking directly on a tower
	if (obj && obj.parent && obj.parent instanceof Tower) {
		// Don't activate tower preview when clicking on a tower
		return;
	}
	towerPreview.visible = true;
	isDragging = true;
	towerPreview.snapToGrid(x, y);
};
game.move = function (x, y, obj) {
	if (isDragging) {
		towerPreview.snapToGrid(x, y);
	}
};
game.up = function (x, y, obj) {
	isDragging = false;
	// Check if player clicked directly on a tower
	if (obj && obj.parent && obj.parent instanceof Tower) {
		var tower = obj.parent;
		// Attempt to upgrade the tower
		if (tower.upgrade()) {
			var notification = game.addChild(new Notification("Tower upgraded!"));
			notification.x = 2048 / 2;
			notification.y = grid.height - 50;
		}
		// Hide tower preview if upgrading an existing tower
		towerPreview.visible = false;
		return;
	}
	// Check placement possibilities
	if (towerPreview.canPlace) {
		// Check if placing here would block the path
		if (!wouldBlockPath(towerPreview.gridX, towerPreview.gridY)) {
			// Place the tower (placeTower will handle gold check internally)
			placeTower(towerPreview.gridX, towerPreview.gridY);
		} else {
			// Show notification that we can't place here
			var notification = game.addChild(new Notification("Tower would block the path!"));
			notification.x = 2048 / 2;
			notification.y = grid.height - 50;
		}
	} else if (towerPreview.blockedByEnemy) {
		// Show notification that an enemy is in the way
		var notification = game.addChild(new Notification("Cannot build: Enemy in the way!"));
		notification.x = 2048 / 2;
		notification.y = grid.height - 50;
	} else if (towerPreview.visible) {
		// Generic notification for other reasons
		var notification = game.addChild(new Notification("Cannot build here!"));
		notification.x = 2048 / 2;
		notification.y = grid.height - 50;
	}
	towerPreview.visible = false;
};
game.update = function () {
	// Spawn enemies periodically
	if (++offset % 100 == 0) {
		var target = grid.spawns[Math.random() * grid.spawns.length >> 0];
		var enemy = enemyLayer.addChild(new Enemy());
		enemy.currentCellX = enemy.cellX = target.x;
		enemy.currentCellY = enemy.cellY = target.y;
		enemies.push(enemy);
	}
	// Update enemies
	for (var a = enemies.length - 1; a >= 0; a--) {
		var enemy = enemies[a];
		// Check if enemy is defeated
		if (enemy.health <= 0) {
			// Clear bullet targeting references
			for (var i = 0; i < enemy.bulletsTargetingThis.length; i++) {
				var bullet = enemy.bulletsTargetingThis[i];
				bullet.targetEnemy = null; // This will cause bullet to destroy itself on next update
			}
			// Award gold and score for defeating enemy
			gold += 1;
			score += 5;
			updateUI();
			// Remove enemy
			enemyLayer.removeChild(enemy);
			enemies.splice(a, 1);
			continue;
		}
		// Update enemy movement
		if (grid.updateEnemy(enemy)) {
			// Enemy reached goal
			enemyLayer.removeChild(enemy);
			enemies.splice(a, 1);
			// Reduce lives when enemy reaches goal
			lives = Math.max(0, lives - 1);
			updateUI();
			// Check if game over (no lives left)
			if (lives <= 0) {
				LK.showGameOver();
			}
		}
	}
	// Update towers
	for (var i = 0; i < towers.length; i++) {
		towers[i].update();
	}
	// Update bullets
	for (var i = bullets.length - 1; i >= 0; i--) {
		bullets[i].update();
		// Remove destroyed bullets
		if (!bullets[i].parent) {
			// If this bullet has a target, remove the bullet from the target's tracking array
			if (bullets[i].targetEnemy) {
				var targetEnemy = bullets[i].targetEnemy;
				var bulletIndex = targetEnemy.bulletsTargetingThis.indexOf(bullets[i]);
				if (bulletIndex !== -1) {
					targetEnemy.bulletsTargetingThis.splice(bulletIndex, 1);
				}
			}
			// Ensure bullet is removed from global bullets array
			bullets.splice(i, 1);
		}
	}
	// Update tower preview placement status on every frame
	// This ensures the placement status updates in real-time as enemies move
	if (towerPreview.visible) {
		towerPreview.checkPlacement();
	}
};

===================================================================
--- original.js
+++ change.js
@@ -821,8 +821,13 @@
 		return false;
 	}
 }
 game.down = function (x, y, obj) {
+	// Check if clicking directly on a tower
+	if (obj && obj.parent && obj.parent instanceof Tower) {
+		// Don't activate tower preview when clicking on a tower
+		return;
+	}
 	towerPreview.visible = true;
 	isDragging = true;
 	towerPreview.snapToGrid(x, y);
 };
@@ -841,8 +846,10 @@
 			var notification = game.addChild(new Notification("Tower upgraded!"));
 			notification.x = 2048 / 2;
 			notification.y = grid.height - 50;
 		}
+		// Hide tower preview if upgrading an existing tower
+		towerPreview.visible = false;
 		return;
 	}
 	// Check placement possibilities
 	if (towerPreview.canPlace) {