function load() {
	let intervalID = window.setInterval(get_active_torrents, 20000);
}

function get_active_torrents() {
	let httpRequest;
	httpRequest = new XMLHttpRequest();
	httpRequest.onreadystatechange = function() {
		if (httpRequest.readyState !== XMLHttpRequest.DONE) { return; }
		if (httpRequest.status !== 200) { return; }
		torrents = JSON.parse(httpRequest.responseText);
		let html_str = '';
		for (let i = 0; i < torrents.length; i++) {
			html_str += '<tr><td class="name">' + torrents[i].name + '</td><td class="state">' + torrents[i].state + '</td><td class="downrate">' + speedrate(torrents[i].downrate) + '</td><td class="uprate">' + speedrate(torrents[i].uprate) + '</td><td class="tracker">' + torrents[i].tracker + "</td>";
		}
		document.getElementById('torrents').children[1].innerHTML = html_str;
	};
	httpRequest.open('GET', get_torrents_uri, true);
	httpRequest.send();
}

function speedrate(rate) {
	let unit = 'B/s';
	if (rate > 1024) {
		rate /= 1024;
		unit = 'KiB/s';
	}
	if (rate > 1024) {
		rate /= 1024;
		unit = 'MiB/s';
	}
	rate = Math.round(rate*10)/10; // different from Python's round()
	return rate + unit;
}