update to support Callbacks and UMD

index.js

@@ -1,47 +1,47 @@
-"use strict";
+'use strict';
 
 (function(root, factory) {
-	if (typeof define === "function" && define.amd) {
+	if (typeof define === 'function' && define.amd) {
 		// AMD
-		define(["fetch"], factory);
-	} else if (typeof exports === "object") {
+		define(['fetch'], factory);
+	} else if (typeof exports === 'object') {
 		// Node, CommonJS-like
-		module.exports = factory(require("node-fetch"));
+		module.exports = factory(require('node-fetch'));
 	} else {
 		// Browser globals (root is window)
 		root.movieInfo = factory(root.fetch);
 	}
 })(this, function(fetch) {
-	//    methods
-	function movieInfo(movie, year) {
+	function movieInfo(movie, year, cb) {
 		// search parameters
 		var search = {
-			key: "9d2bff12ed955c7f1f74b83187f188ae",
-			base: "https://api.themoviedb.org",
+			key: '9d2bff12ed955c7f1f74b83187f188ae',
+			base: 'https://api.themoviedb.org',
 			year: null,
 			movie: movie
 		};
 
-		if (typeof movie !== "string") {
-			throw new Error("Expected a string");
-		} else if (typeof year !== "string") {
+		if (typeof movie !== 'string') {
+			throw new Error('Expected a string');
+		} else if (typeof year === 'function') {
+			cb = year;
+		} else if (typeof year === 'string' || typeof year === 'number') {
 			search.year = year;
 		}
 
 		var url =
 			search.base +
 			encodeURI(
-				"/3/search/movie?api_key=" +
+				'/3/search/movie?api_key=' +
 					search.key +
-					"&query=" +
+					'&query=' +
 					search.movie +
-					(search.year !== null ? "&year=" + search.year : "")
+					(search.year !== null ? '&year=' + search.year : '')
 			);
 
-		// Promise
-		return fetch(url, {
-			method: "GET",
-			mode: "no-cors"
+		// Request
+		var response = fetch(url, {
+			method: 'GET',
 		})
 			.then(
 				function(response) {
@@ -52,26 +52,33 @@
 				}
 			)
 			.then(function(json) {
-				if (json && typeof json.status_message !== "undefined") {
-					return Promise.reject("JSON Error: " + json.status_message);
+				if (json && typeof json.status_message !== 'undefined') {
+					return Promise.reject('JSON Error: ' + json.status_message);
 				}
 				if (json && json.results && json.results.length === 0) {
 					// Retry failed search without year
 					if (search.year !== null) {
 						search.year = null;
 						return movieInfo(search.movie, null);
 					} else {
-						return Promise.reject("Search Error: No results found");
+						return Promise.reject('Search Error: No results found');
 					}
 				} else {
-					return json.results[0];
+					return json && json.results[0];
 				}
 			})
 			.catch(function(error) {
 				return error;
 			});
+
+			// Callback or return Promise
+			if (cb) {
+				response.then(cb);
+			} else {
+				return response;
+			}
 	}
 
-	//    exposed public method
+	// exposed public method
 	return movieInfo;
 });

test.js

@@ -3,6 +3,39 @@
 import test from 'ava';
 var movieInfo = require('./index');
 
+test('calls the callback without a year', async t => {
+	t.plan(1);
+
+	const title = await new Promise((resolve, reject) => {movieInfo('crash', r => {
+			resolve(r.title)
+		});
+	});	
+
+	t.is(title, 'Crash');
+});
+
+test('calls the callback with a year', async t => {
+	t.plan(1);
+
+	const title = await new Promise((resolve, reject) => {movieInfo('crash', '2005', r => {
+			resolve(r.title)
+		});
+	});	
+
+	t.is(title, 'Crash');
+});
+
+test('calls the callback with a numeric year', async t => {
+	t.plan(1);
+
+	const title = await new Promise((resolve, reject) => {movieInfo('crash', 2005, r => {
+			resolve(r.title)
+		});
+	});	
+
+	t.is(title, 'Crash');
+});
+
 test('returns an object', async t => {
 	t.plan(1);