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/*
<!-- XXX -->
<link rel="stylesheet"
href="https://codepen.io/memetican/pen/vYQjzLm/e7b9dc532f9c872b346c70dab06a4755.css">
<script async
src="https://codepen.io/memetican/pen/vYQjzLm/e7b9dc532f9c872b346c70dab06a4755.js"
></script>
*/
// Haversine formula to calculate the distance between two points
function calculateDistance(lat1, lon1, lat2, lon2) {
const R = 6371; // Radius of Earth in km
const dLat = (lat2 - lat1) * Math.PI / 180;
const dLon = (lon2 - lon1) * Math.PI / 180;
const a = Math.sin(dLat / 2) * Math.sin(dLat / 2) +
Math.cos(lat1 * Math.PI / 180) * Math.cos(lat2 * Math.PI / 180) *
Math.sin(dLon / 2) * Math.sin(dLon / 2);
const c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
return R * c;
}
// Function to calculate and store distance for each item
function calculateDistancesForItems(items, callback) {
items.forEach(item => {
const element = item.element; // Access the actual HTML element
if (element instanceof HTMLElement) {
const placeLat = parseFloat(element.getAttribute('data-latitude'));
const placeLon = parseFloat(element.getAttribute('data-longitude'));
if (!isNaN(placeLat) && !isNaN(placeLon)) {
const distance = calculateDistance(userLat, userLon, placeLat, placeLon);
element.setAttribute('data-distance', distance); // Store numeric distance for sorting
item.props.distance.values.clear();
item.props.distance.values.add(`"${distance}"`);
// Display the distance without "km" or extra characters
const distanceElement = element.querySelector('[calc-distance]');
if (distanceElement) {
distanceElement.innerText = distance.toFixed(2) + " km distance"; // Only display the numeric value
}
}
}
});
// Callback to proceed with sorting after distances are calculated
if (callback) {
callback();
}
}
async function init() {
// Determine user location
window.userLat = 0; // default
window.userLon = 0; // default
await getUserLocation();
console.log(window.userLat, window.userLon);
window.fsAttributes = window.fsAttributes || [];
// Initialize CMS Load to ensure items are loaded before calculating distances
window.fsAttributes.push([
'cmsload',
async (listInstances: CMSList[]) => {
const [listInstance] = listInstances;
console.log("cmsload callback")
// Run the distance calculation for items already rendered on the first page
const renderedItems = listInstance.items;
calculateDistancesForItems(renderedItems, () => {
console.log(renderedItems);
// Sort items after distance calculation
console.log("re-initializing cmssort");
window.fsAttributes.cmssort.init();
});
},
]);
}
async function getUserLocation() {
if (navigator.geolocation) {
try {
// getCurrentPosition is async, we need it promise-based
const position = await new Promise((resolve, reject) => {
navigator.geolocation.getCurrentPosition(resolve, reject);
});
window.userLat = position.coords.latitude;
window.userLon = position.coords.longitude;
// Find elements with custom attributes and update their text content
const latElement = document.querySelector('[info="latitude"]');
const lonElement = document.querySelector('[info="longitude"]');
if (latElement) {
latElement.textContent = window.userLat.toFixed(6); // Display the latitude
}
if (lonElement) {
lonElement.textContent = window.userLon.toFixed(6); // Display the longitude
}
// Now the values are available and ready to use
console.log(`Latitude: ${userLat}, Longitude: ${userLon}`);
} catch (error) {
alert(`Error: ${error.message}`);
}
} else {
alert("Geolocation is not supported by this browser.");
}
}
init();
Also see: Tab Triggers