refactored code and added win/lose popups

assets/config.json

@@ -1,13 +1,16 @@
 {
 	"touchscreen": {
+		"enabled": true,
 		"mode": "swipe",
 		"deadzone": 50,
 		"buffer": false
 	},
 	"keyboard": {
+		"enabled": true,
 		"buffer": false
 	},
 	"gamepad": {
+		"enabled": true,
 		"deadzone": 0.5,
 		"buffer": true
 	}

assets/levelList.json

@@ -12,7 +12,8 @@
 		"levelDisplay": "Level <n>",
 		"levels": [
 			1, 2, 3, 4, 5
-		]
+		],
+		"nextLevel": true
 	},
 	"arcade": {
 		"desc": "Have fun just like in the good ol' days, walls wrap around, fruits respawn and speed increases",
@@ -31,6 +32,7 @@
 			"Survival",
 			"Versus"
 		],
+		"nextLevel": false,
 		"levelDesc": [
 			"The old classic, try to get as high as a score as you can",
 			"Get a score as high as you can in 30 seconds",

src/js/input.js

@@ -0,0 +1,152 @@
+let currentInputs={};
+let handlers=[];
+let config;
+
+const toAngleMagnitude=(x, y) => {
+	return {
+		angle: ((Math.atan2(x, y)+2*Math.PI)%(2*Math.PI))/Math.PI,
+		magnitude: Math.hypot(x, y)
+	};
+};
+
+const handleAngleMagnitude=(x, y, threshold=0, fn=null, clearBuffer=false) => {
+	const {angle, magnitude}=toAngleMagnitude(x, y);
+
+	if(magnitude>threshold) {
+		if(angle>.25 && angle <.75) inputs.right=true;
+		else if(angle>.75 && angle<1.25) inputs.up=true;
+		else if(angle>1.25 && angle<1.75) inputs.left=true;
+		else inputs.down=true;
+
+		if(clearBuffer) inputs.clearBuffer=true;
+		if(fn) fn(angle, magnitude);
+	}
+}
+
+const handleCrosspad=(() => {
+	const fn=e =>
+		handleAngleMagnitude(
+			e.touches[0].clientX-window.innerWidth/2,
+			e.touches[0].clientY-window.innerHeight/2,
+			0,
+			null,
+			!config.touchscreen.buffer
+		);
+	return {
+		touchstart: fn,
+		touchmove: fn
+	};
+})();
+
+const handleKeyboard={
+	keydown: e => {
+		let inputs=currentInputs;
+		if(e.key=='ArrowUp') inputs.up=true;
+		else if(e.key=='ArrowDown') inputs.down=true;
+		else if(e.key=='ArrowLeft') inputs.left=true;
+		else if(e.key=='ArrowRight') inputs.right=true;
+
+		if(!config.keyboard.buffer) inputs.clearBuffer=true;
+	}
+};
+
+const handleJoystick=(() => {
+	let center={
+		x: 0,
+		y: 0
+	};
+	return {
+		touchstart: e => {
+			center.x=e.touches[0].clientX;
+			center.y=e.touches[0].clientY;
+		},
+		touchmove: e =>
+			handleAngleMagnitude(
+				e.touches[0].clientX-center.x,
+				e.touches[0].clientY-center.y,
+				config.touchscreen.deadzone,
+				null,
+				!config.touchscreen.buffer
+			)
+	}
+});
+
+const handleSwipe=(() => {
+	let center={
+		x: 0,
+		y: 0
+	};
+	let resetCenter=e => {
+		center.x=e.touches[0].clientX;
+		center.y=e.touches[0].clientY;
+	};
+	return {
+		touchstart: resetCenter,
+		touchmove: e =>
+			handleAngleMagnitude(
+				e.touches[0].clientX-center.x,
+				e.touches[0].clientY-center.y,
+				config.touchscreen.deadzone,
+				() => resetCenter(e),
+				!config.touchscreen.buffer
+			)
+	}
+});
+
+const handleGamepads={
+	frame: () => {
+		const gp=navigator.getGamepads()[0];
+		let inputs=currentInputs;
+		if(!gp || !gp.axes) return;
+
+		handleAngleMagnitude(
+			gp.axes[0],
+			gp.axes[1],
+			config.gamepad.deadzone,
+			null,
+			!config.gamepad.buffer
+		);
+	}
+};
+
+const handleEvent=(type, evt) => {
+	for(let handler of handlers) {
+		let fn=handler[type];
+		if(fn) fn(evt);
+	}
+};
+
+const enableHandler=handler => {
+	if(!handlers.includes(handler)) handlers.push(handler);
+};
+const disableHandler=handler => {
+	let idx=handlers.indexOf(handler);
+	if(idx!=-1) handlers.splice(idx, 1);
+};
+
+const updateConfig=cfg =>
+	config=cfg;
+
+const clear=() =>
+	Object
+		.keys(currentInputs)
+		.forEach(key => delete currentInputs[key]);
+
+for(let type of ['keydown', 'touchstart', 'touchmove']) {
+	window.addEventListener(type, handleEvent.bind(null, type));
+}
+
+return module.exports={
+	inputs: currentInputs,
+	clear,
+	enableHandler, disableHandler,
+	framefn: handleEvent.bind(null, 'frame'),
+	availableHandlers: {
+		keyboard: handleKeyboard,
+		gamepad: handleGamepads,
+		touchscreenCrosspad: handleCrosspad,
+		touchscreenJoystick: handleJoystick,
+		touchscreenSwipe: handleSwipe
+	},
+	updateConfig
+};

src/js/levels.js

@@ -0,0 +1,18 @@
+const cache=Object.create(null);
+
+const get=async filename => {
+	if(cache[filename]) return cache[filename];
+	const req=await fetch('levels/'+filename);
+	const json=await req.json();
+	return cache[filename]=json;
+};
+
+const clearCache=() =>
+	Object
+		.keys(cache)
+		.forEach(key => delete cache[key]);
+
+return module.exports={
+	get,
+	clearCache
+};

src/js/main.js

@@ -1,22 +1,35 @@
 (async () => {
-	location.hash='';
 
+	// load modules
 	const assets=require('assets');
 	const Popup=require('popup');
 	const SnekGame=require('snek');
+	const input=require('input');
+	const levels=require('levels');
 
+	// get a known state
 	await new Promise(ok => assets.onReady(ok));
+	location.hash='menu';
 
+	// get our DOM in check
 	const main=document.querySelector('main');
 	const nav=main.querySelector('nav');
 	const canvas=main.querySelector('canvas');
 
-	const config=assets.get('config');
+	// load config
+	const config=assets.get('config'); //TODO use an actual config module
 
+	// load data from server
+	const levelList=assets.get('levelList');
+
+	// get our global variables
 	let currentGame=null;
-	let currentInputs={};
 
-	const resizeCanvas=() => {
+	// forward-declare functions
+	let resizeCanvas, getLevel, startGame, handleWin, handleDeath, menu, help;
+
+	// handle window resize and fullscreen
+	resizeCanvas=() => {
 		if(document.fullscreenElement) {
 			canvas.width=screen.width;
 			canvas.height=screen.height;
@@ -27,8 +40,35 @@
 	};
 	resizeCanvas();
 	window.addEventListener('resize', resizeCanvas);
+	window.addEventListener('keydown', async e => {
+		if(e.key=='f') {
+			if(document.fullscreenElement) await document.exitFullscreen();
+			else await main.requestFullscreen();
+			resizeCanvas();
+		}
+	});
 
-	const levelList=assets.get('levelList');
+	// get a level for a category and an id
+	getLevel=(category, id) => {
+		const cat=levelList[category];
+		id=''+id;
+
+		const displayName=cat.levelDisplay
+			.replace(/<n>/g, id)
+			.replace(/<l>/g, id.toLowerCase());
+		const fileName=cat.levelFilename
+			.replace(/<n>/g, id)
+			.replace(/<l>/g, id.toLowerCase());
+		const levelString=category+'/'+id+'/'+fileName;
+
+		return {
+			displayName,
+			fileName,
+			levelString
+		};
+	};
+
+	// buid menu from level list
 	Object.keys(levelList).forEach(category => {
 		const cat=levelList[category];
 
@@ -41,16 +81,10 @@
 
 		const ul=section.appendChild(document.createElement('ul'));
 		cat.levels.forEach((level, i) => {
-			level=''+level;
-			const displayName=cat.levelDisplay
-				.replace(/<n>/g, level)
-				.replace(/<l>/g, level.toLowerCase());
-			const fileName=cat.levelFilename
-				.replace(/<n>/g, level)
-				.replace(/<l>/g, level.toLowerCase());
+			const {displayName, fileName, levelString}=getLevel(category, level);
 			const li=ul.appendChild(document.createElement('li'));
 			const a=li.appendChild(document.createElement('a'));
-			a.href='#'+category+'/'+fileName;
+			a.href='#'+levelString;
 			a.innerText=displayName;
 			if(cat.levelDesc) {
 				const span=li.appendChild(document.createElement('span'));
@@ -59,45 +93,62 @@
 		});
 	});
 
-	const handleGamepads=() => {
-		const gp=navigator.getGamepads()[0];
-		let inputs=currentInputs;
-		if(!gp || !gp.axes) return;
+	// start a new game
+	startGame=async (category, levelId, filename) => {
+		// stop any running games
+		if(currentGame) currentGame.playing=false;
 
-		const magnitude=Math.hypot(gp.axes[0], gp.axes[1]);
-		const angle=((Math.atan2(gp.axes[0], gp.axes[1])+2*Math.PI)%(2*Math.PI))/Math.PI;
-		if(magnitude>config.gamepad.deadzone) {
-			if(angle>.25 && angle <.75) inputs.right=true;
-			else if(angle>.75 && angle<1.25) inputs.up=true;
-			else if(angle>1.25 && angle<1.75) inputs.left=true;
-			else inputs.down=true;
-		}
-
-		if(!config.gamepad.buffer) inputs.clearBuffer=true;
-	};
-
-	const startGame=async (category, filename) => {
-		//TODO migrate relevant code here
-	};
-
-	window.addEventListener('hashchange', async () => {
-		nav.classList.add('hidden');
-
-		const [_, category, filename]=location.hash.match(/([a-zA-Z0-9_-]+?)\/(.+)/);
+		// load rules and level from cache or server
 		const rules=levelList[category].rules || {};
-		const level=await (async () => {
-			const resp=await fetch('levels/'+filename);
-			return await resp.json();
-		})();
+		const level=await levels.get(filename);
 
-		const snek=new SnekGame(level, canvas, rules);
-		canvas.classList.remove('hidden');
-		snek.start();
+		// create the game and attach the callbacks
+		const snek=currentGame=new SnekGame(level, canvas, rules);
 		snek.callback=evt => {
 			if(evt=='tick') {
-				if(navigator.getGamepads) handleGamepads();
-				snek.handleInputs(currentInputs);
+				input.framefn();
+				snek.handleInputs(input.inputs);
 			} else if(evt=='win') {
+				handleWin(snek);
+			} else if(evt=='die') {
+				handleDeath(snek);
+			}
+		};
+
+		// setup the DOM
+		nav.classList.add('hidden');
+		canvas.classList.remove('hidden');
+
+		// push some userdata to the snake
+		snek.userdata={
+			category,
+			levelId,
+			filename
+		};
+
+		// reset the inputs
+		input.clear();
+
+		// start the actual game
+		snek.start();
+	};
+
+	// return to the menu
+	menu=() => {
+		// stop any running games
+		if(currentGame) currentGame.playing=false;
+
+		// setup the DOM
+		nav.classList.remove('hidden');
+		canvas.classList.add('hidden');
+	};
+
+	// display the win popup
+	handleWin=async snek => {
+		// get userdata back
+		const {category, levelId, filename}=snek.userdata;
+
+		// create and configure popup
 		let popup=new Popup("Finished!");
 		popup.addStrong("You won!");
 		popup.addContent({
@@ -107,102 +158,83 @@
 		});
 		popup.buttons={
 			retry: "Retry",
-					next: "Next level",
 			menu: "Main menu"
 		};
-				popup.display();
-				//TODO do something with the result
+		if(levelList[category].nextLevel) {
+			let nextId=(+levelId)+1;
+			if(levelList[category].levels.includes(nextId)) popup.buttons.next="Next level";
+		}
+
+		// show the actual popup
+		let result=await popup.display(main);
+
+		// act on it
+		if(result=='retry') {
+			startGame(category, levelId, filename);
+		} else if(result=='menu') {
+			location.hash='menu';
+		} else if(result=='next') {
+			let nextId=(+levelId)+1;
+			let {levelString}=getLevel(category, nextId)
+			location.hash=levelString;
 		}
 	};
-		currentGame=snek;
-	});
 
-	window.addEventListener('keydown', async e => {
-		e.preventDefault();
-		if(e.key=='f') {
-			if(document.fullscreenElement) await document.exitFullscreen();
-			else await main.requestFullscreen();
-			resizeCanvas();
+	// display the death popup
+	handleDeath=async snek => {
+		// get userdata back
+		const {category, levelId, filename}=snek.userdata;
+
+		// create and configure popup
+		let popup=new Popup("Finished!");
+		popup.addStrong("You died...");
+		popup.addContent({
+			"Time": snek.playTime/1000+'s',
+			"Score": snek.score,
+			"Final length": snek.snake.length
+		});
+		popup.buttons={
+			retry: "Retry",
+			menu: "Main menu"
+		};
+
+		// show the actual popup
+		let result=await popup.display(main);
+
+		// act on it
+		if(result=='retry') {
+			startGame(category, levelId, filename);
+		} else if(result=='menu') {
+			location.hash='menu';
 		}
+	};
 
-		let inputs=currentInputs;
-		if(e.key=='ArrowUp') inputs.up=true;
-		else if(e.key=='ArrowDown') inputs.down=true;
-		else if(e.key=='ArrowLeft') inputs.left=true;
-		else if(e.key=='ArrowRight') inputs.right=true;
+	// handle page navigation
+	window.addEventListener('hashchange', () => {
+		const hash=location.hash.substr(1);
 
-		if(!config.keyboard.buffer) inputs.clearBuffer=true;
+		if(hash=='' || hash=='menu') return menu();
+		else if(hash=='help') return help();
+
+		const [_, category, levelId, filename]=location.hash.match(/([a-zA-Z0-9_-]+?)\/([a-zA-Z0-9_-]+?)\/(.+)/);
+		startGame(category, levelId, filename);
 	});
 
+	// enable input methods according to config
+	if(config.keyboard.enabled) {
+		input.enableHandler(input.availableHandlers.keyboard);
+	}
+	if(config.gamepad.enabled) {
+		input.enableHandler(input.availableHandlers.gamepad);
+	}
+	if(config.touchscreen.enabled) {
 		if(config.touchscreen.mode=='crosspad') {
-		const handleTouch=e => {
-			let x=e.touches[0].clientX-window.innerWidth/2;
-			let y=e.touches[0].clientY-window.innerHeight/2;
-			const angle=((Math.atan2(x, y)+2*Math.PI)%(2*Math.PI))/Math.PI;
-
-			let inputs=currentInputs;
-			if(angle>.25 && angle <.75) inputs.right=true;
-			else if(angle>.75 && angle<1.25) inputs.up=true;
-			else if(angle>1.25 && angle<1.75) inputs.left=true;
-			else inputs.down=true;
-
-			if(!config.touchscreen.buffer) inputs.clearBuffer=true;
-		};
-		window.addEventListener('touchstart', handleTouch);
-		window.addEventListener('touchmove', handleTouch);
+			input.enableHandler(input.availableHandlers.touchscreenCrosspad);
+		} else if(config.touchscreen.mode=='joystick') {
+			input.enableHandler(input.availableHandlers.touchscreenJoystick);
+		} else if(config.touchscreen.mode=='swipe') {
+			input.enableHandler(input.availableHandlers.touchscreenSwipe);
 		}
-
-	if(config.touchscreen.mode=='joystick') {
-		let center={x: 0, y: 0};
-		window.center=center;
-		window.addEventListener('touchstart', e => {
-			center.x=e.touches[0].clientX;
-			center.y=e.touches[0].clientY;
-		});
-		window.addEventListener('touchmove', e => {
-			let x=e.touches[0].clientX-center.x;
-			let y=e.touches[0].clientY-center.y;
-			const angle=((Math.atan2(x, y)+2*Math.PI)%(2*Math.PI))/Math.PI;
-			const magnitude=Math.hypot(x, y);
-
-			let inputs=currentInputs;
-			if(magnitude>config.touchscreen.deadzone) {
-				if(angle>.25 && angle <.75) inputs.right=true;
-				else if(angle>.75 && angle<1.25) inputs.up=true;
-				else if(angle>1.25 && angle<1.75) inputs.left=true;
-				else inputs.down=true;
 	}
-
-			if(!config.touchscreen.buffer) inputs.clearBuffer=true;
-		});
-	}
-
-	if(config.touchscreen.mode=='swipe') {
-		let center={x: 0, y: 0};
-		window.center=center;
-		window.addEventListener('touchstart', e => {
-			center.x=e.touches[0].clientX;
-			center.y=e.touches[0].clientY;
-		});
-		window.addEventListener('touchmove', e => {
-			let x=e.touches[0].clientX-center.x;
-			let y=e.touches[0].clientY-center.y;
-			const angle=((Math.atan2(x, y)+2*Math.PI)%(2*Math.PI))/Math.PI;
-			const magnitude=Math.hypot(x, y);
-
-			let inputs=currentInputs;
-			if(magnitude>config.touchscreen.deadzone) {
-				if(angle>.25 && angle <.75) inputs.right=true;
-				else if(angle>.75 && angle<1.25) inputs.up=true;
-				else if(angle>1.25 && angle<1.75) inputs.left=true;
-				else inputs.down=true;
-
-				center.x=e.touches[0].clientX;
-				center.y=e.touches[0].clientY;
-			}
-
-			if(!config.touchscreen.buffer) inputs.clearBuffer=true;
-		});
-	}
-
+	input.updateConfig(config);
 })();

src/js/popup.js

@@ -46,7 +46,7 @@ class Popup {
 		this.content.push(objToDom({[Popup.STRONG]: cnt}));
 	}
 
-	async display() {
+	async display(parent=document.body) {
 		let outer=document.createElement('div');
 		outer.classList.add('popup');
 		let popup=outer.appendChild(document.createElement('div'));
@@ -67,7 +67,7 @@ class Popup {
 		});
 		buttons.forEach(btn => buttonSection.appendChild(btn));
 
-		document.body.appendChild(outer);
+		parent.appendChild(outer);
 
 		const code=await Promise.race(buttons.map(btn => new Promise(ok => {
 			btn.addEventListener('click', e => {
@@ -76,7 +76,7 @@ class Popup {
 			});
 		})));
 
-		document.body.removeChild(outer);
+		parent.removeChild(outer);
 		return code;
 	}
 }