Add GA event tracking on widget retailer links

gethatch.com-GA-event-widget.js

//Please ask Hatch to provide a list of all retailer IDs vs names
const retailer_mapping = {
	94349 : 'MSI Store',
	89105 : 'Walmart',
};

//Listener on any hatch links
document.addEventListener( "click", hatchRetailerWidgetClick );
function hatchRetailerWidgetClick(ev){
    const el = ev.target;
	const hatch_link  = el.closest('a[href*="https://gethatch.com/wtbonline"]');
    if(hatch_link !== null){
		console.log('Click on a Hatch link : ', hatch_link);
		//extract retailer ID 		
		const reg =  /.+?:\/\/.+?(\/.+?)(?:#|\?|$)/;
		const pathname = reg.exec(hatch_link)[1];
		const path_arr = pathname.split('/');
		
		//Retailer ID
		const retailer_id = path_arr[3];
		console.log('retailer ID : ', retailer_id);
		
		//Retailer name
		const retailer_name = ((retailer_mapping[retailer_id] !== undefined)?retailer_mapping[retailer_id]:'NA');
		console.log('retailer name : ', retailer_name);
		
		//Add gtag event, make sure you add the gtag core script as well
		gtag('event', 'ps_retailer_click', {
		  'retailer_id': retailer_id,
		  'retailer_name': retailer_name,
		});
    }
}