move merge saving fn to itemservice

src/itemService.js

@@ -65,6 +65,50 @@
 				.catch(error => console.log(error));
 		},
 
+		/**
+		 * Saves the passed items in the database.
+		 * @param {Array} items to be saved in DB
+		 */
+		saveItems(items) {
+			var d = deferred();
+			if (window.IS_EXTENSION) {
+				// save new items
+				window.db.local.set(items, d.resolve);
+				// Push in new item IDs
+				window.db.local.get(
+					{
+						items: {}
+					},
+					function(result) {
+						/* eslint-disable guard-for-in */
+						for (var id in items) {
+							result.items[id] = true;
+						}
+						window.db.local.set({
+							items: result.items
+						});
+						/* eslint-enable guard-for-in */
+					}
+				);
+			} else {
+				window.db.getDb().then(remoteDb => {
+					const batch = remoteDb.batch();
+					/* eslint-disable guard-for-in */
+					for (var id in items) {
+						batch.set(remoteDb.doc(`items/${id}`), items[id]);
+						batch.update(remoteDb.doc(`users/${window.user.uid}`), {
+							[`items.${id}`]: true
+						});
+						// Set these items on out cached user object too
+						window.user.items[id] = true;
+					}
+					batch.commit().then(d.resolve);
+					/* eslint-enable guard-for-in */
+				});
+			}
+			return d.promise;
+		},
+
 		async removeItem(id) {
 			if (window.IS_EXTENSION) {
 				var d = deferred();