tick(), wait(), normalize(), xhr(), listen()

[rudiedirkx]

Include alongside ready() and load():

wait = function(ms) {
	return new Promise(function(resolve) {
		setTimeout(resolve, ms || 1);
	});
};

tick = function(callback) {
	var state, ticker, control, t1s, t2s;
	state = {active: true, iteration: 0};
	ticker = function(extra) {
		state.iteration++;
		callback(control);
		state.active && extra !== true && requestAnimationFrame(ticker);
	};
	requestAnimationFrame(ticker);
	t1s = setTimeout(ticker, 1000, true);
	t2s = setTimeout(ticker, 2000, true);
	control = {
		state: state,
		stop: function() {
			state.active = false;
			clearTimeout(t1s);
			clearTimeout(t2s);
		}
	};
	return control;
};

normalize = function(str, limit = 0) {
	str = str.trim().toLowerCase().replace(/[^a-z0-9\-]+/ig, '-').replace(/(^\-+|\-+$)/g, '').replace(/\-+/g, '-');
	if (limit) {
		str = str.split('-').slice(0, limit).join('-');
	}
	return str;
};

xhr = function(method, url, data) {
	return new Promise(function(resolve, reject) {
		var req = new XMLHttpRequest;
		req.open(method, url, true);
		if (method.toUpperCase() == 'POST') {
			req.setRequestHeader('Content-type', 'application/x-www-form-urlencoded');
		}
		req.onload = function(e) {
			resolve(this);
		};
		req.onerror = function(e) {
			reject(this);
		};
		req.send(data);
	});
};

listen = function(targets, callback) {
	var curs;

	if ( targets.constructor != Array ) {
		targets = [targets];
	}

	ready(function() {
		curs = targets.map(fn => fn());
		callback([]);
	});

	tick(function() {
		if ( !curs ) return;

		var news = targets.map(fn => fn());

		var diffs = [];
		curs.forEach((old, i) => {
			if ( old !== news[i] ) {
				diffs.push(i);
			}
		});

		if ( diffs.length) {
// console.log('CHANGES', curs, news);
			callback(diffs);
			curs = news;
		}
	});
};