add JsDoc and small code improvements

src/background.js

@@ -1,9 +1,18 @@
 import Config from "./config.js";
 
-function fetchJson(url) {
-	return fetch(url).then((response) => (response.json()));
+/**
+ * @param {string} url
+ * @returns {Promise<any>}
+ */
+async function fetchJson(url) {
+	const response = await fetch(url);
+	return response.json();
 }
 
+/**
+ * @param {number} days
+ * @returns {Promise<any>}
+ */
 function fetchCalendar(days = 28) {
 	let url = `${Config.calenderUrl}?o=json`;
 	if (days) {
@@ -12,10 +21,16 @@ function fetchCalendar(days = 28) {
 	return fetchJson(url);
 }
 
+/**
+ * @returns {Promise<any>}
+ */
 function fetchSpaceApi() {
 	return fetchJson(Config.spaceApiUrl);
 }
 
+/**
+ * @param {boolean} open
+ */
 async function updateBadge(open) {
 	let badgeText, badgeColor;
 	if (open) {
@@ -32,6 +47,9 @@ async function updateBadge(open) {
 	}
 }
 
+/**
+ * @param {boolean} open
+ */
 function sendNotification(open) {
 	browser.notifications.create('status-change', {
 		type: 'basic',

src/popup.js

@@ -19,6 +19,9 @@ const doorOpenSVG = `
 
 const dateTimeFormat = Intl.DateTimeFormat([], {dateStyle: "medium", timeStyle: "short"});
 
+/**
+ * @param {Event} event
+ */
 async function linkElementClickListener(event) {
 	try {
 		await browser.tabs.create({url: event.currentTarget.dataset.url});
@@ -45,6 +48,9 @@ async function init() {
 }
 init();
 
+/**
+ * @param {object} nextEvents
+ */
 function updateNextEvent(nextEvents) {
 	const calendarElement = document.getElementById('calendar');
 	calendarElement.innerText = '';
@@ -54,9 +60,7 @@ function updateNextEvent(nextEvents) {
 		const strongElement = document.createElement('strong');
 		strongElement.append(hintNode);
 		calendarElement.append(strongElement);
-		return;
-	}
-
+	} else {
 		const nextEventDate = nextEvents[0].begin.substr(0, 10);
 		const nextEventDateEvents = nextEvents.filter((nextEvent) => (nextEvent.begin.startsWith(nextEventDate)));
 
@@ -78,8 +82,12 @@ function updateNextEvent(nextEvents) {
 			}
 			calendarElement.append(divElement);
 		});
+	}
 }
 
+/**
+ * @param {object} spaceApi
+ */
 function updateSpaceApiJson(spaceApi) {
 	const spaceApiElement = document.querySelector('#space-api code');
 	const json = JSON.stringify(spaceApi, null, 2).replace(/ /g, '&nbsp;').replace(/\n/g, '<br/>');
@@ -89,6 +97,9 @@ function updateSpaceApiJson(spaceApi) {
 	// spaceApiElement.append(jsonNode);
 }
 
+/**
+ * @param {object} spaceApi
+ */
 function updateState(spaceApi) {
 	const stateElement = document.getElementById('state');
 	const since = new Date(spaceApi.state.lastchange * 1000);