window.ExactMetricsDualTracker.helpers.mapProductItem = function (uaItem) {
				var prefixIndex, prefixKey, mapIndex;

				var toBePrefixed = ['id', 'name', 'list_name', 'brand', 'category', 'variant'];

				var item = {};

				var fieldMap = {
					'price': 'price',
					'list_position': 'index',
					'quantity': 'quantity',
					'position': 'index',
				};

				for (mapIndex in fieldMap) {
					if (uaItem.hasOwnProperty(mapIndex)) {
						item[fieldMap[mapIndex]] = uaItem[mapIndex];
					}
				}

				for (prefixIndex = 0; prefixIndex < toBePrefixed.length; prefixIndex++) {
					prefixKey = toBePrefixed[prefixIndex];
					if (typeof uaItem[prefixKey] !== 'undefined') {
						item['item_' + prefixKey] = uaItem[prefixKey];
					}
				}

				return item;
			};

			ExactMetricsDualTracker.trackers['view_item_list'] = function (parameters) {
				var items = parameters.items;
				var listName, itemIndex, item, itemListName;
				var lists = {
					'_': {items: [], 'send_to': exactmetrics_frontend.v4_id},
				};

				for (itemIndex = 0; itemIndex < items.length; itemIndex++) {
					item = ExactMetricsDualTracker.helpers.mapProductItem(items[itemIndex]);

					if (typeof item['item_list_name'] === 'undefined') {
						lists['_'].items.push(item);
					} else {
						itemListName = item['item_list_name'];
						if (typeof lists[itemListName] === 'undefined') {
							lists[itemListName] = {
								'items': [],
								'item_list_name': itemListName,
								'send_to': exactmetrics_frontend.v4_id,
							};
						}

						lists[itemListName].items.push(item);
					}
				}

				for (listName in lists) {
					__gtagDataLayer('event', 'view_item_list', lists[listName]);
				}
			};

			ExactMetricsDualTracker.trackers['select_content'] = function (parameters) {
				const items = parameters.items.map(ExactMetricsDualTracker.helpers.mapProductItem);
				__gtagDataLayer('event', 'select_item', {items: items, send_to: parameters.send_to});
			};

			ExactMetricsDualTracker.trackers['view_item'] = function (parameters) {
				const items = parameters.items.map(ExactMetricsDualTracker.helpers.mapProductItem);
				__gtagDataLayer('event', 'view_item', {items: items, send_to: parameters.send_to});
			};