https://www.kitepharma.com/Areas/Kite/Content/mapbox/assets/mapbox/js/utilities.js

1/**
2 * @file Various utility functions
3 */
4
5/**
6 * Create an element from a string
7 * @param {string} string - String to create an element from
8 * @returns {Element}
9 */
10export function createElement(string) {
11	const div = document.createElement('div');
12	div.innerHTML = string.trim();
13
14	return div.firstChild;
15}
16
17/**
18 * Replace the handlebars in a string with data.
19 * @param {*} template - String to replace handlebars in
20 * @param {*} data - Data to replace handlebars with
21 * @returns {string}
22 */
23
24export function updateTemplate(text, data) {
25	const matches = text.match(/\{\{(.*?)\}\}/g);
26
27	let copy = text;
28
29	matches.map((match) => {
30		const key = match.replace(/{|}/g, '');
31		const value = data[key];
32
33		copy = copy.replace(match, value);
34
35		return copy;
36	});
37
38	return copy;
39}
40
41/**
42 * Fetch data from a URL and cache it in localStorage
43 * @param {string} url - URL to fetch
44 * @returns {Promise}
45 */
46export function fetchWithCache(url) {
47	if (localStorage.getItem(url)) {
48		return new Promise((resolve, reject) => {
49			return resolve(JSON.parse(localStorage.getItem(url)));
50		});
51	}
52
53	return fetch(url)
54		.then((r) => r.json())
55		.then((data) => {
56			localStorage.setItem(url, JSON.stringify(data));
57
58			return data;
59		})
60		.then((data) => data);
61}
62
63/**
64 * Get the distance between two points in miles
65 * @param {Array} p1 - [lng, lat]
66 * @param {Array} p2 - [lng, lat]
67 */
68export function getDistance(p1, p2) {
69	p1 = {
70		lng: p1[0],
71		lat: p1[1]
72	};
73
74	p2 = {
75		lng: p2[0],
76		lat: p2[1]
77	};
78
79	const R = 3958.8;
80	const φ1 = (p1.lat * Math.PI) / 180;
81	const φ2 = (p2.lat * Math.PI) / 180;
82	const Δφ = ((p2.lat - p1.lat) * Math.PI) / 180;
83	const Δλ = ((p2.lng - p1.lng) * Math.PI) / 180;
84
85	const a =
86		Math.sin(Δφ / 2) * Math.sin(Δφ / 2) +
87		Math.cos(φ1) * Math.cos(φ2) * Math.sin(Δλ / 2) * Math.sin(Δλ / 2);
88
89	const c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
90
91	const d = R * c;
92
93	return d;
94}