Added frontend outline

public_html/js/DI.js

@@ -0,0 +1,65 @@
+var App = App || {};
+
+App.DI = (function() {
+
+	var STRIP_COMMENTS = /((\/\/.*$)|(\/\*[\s\S]*?\*\/))/mg;
+	var ARGUMENT_NAMES = /([^\s,]+)/g;
+
+	var factories = {};
+	var instances = {};
+
+	function get(key) {
+		var instance = instances[key];
+		if (!instance) {
+			var factory = factories[key];
+			if (!factory)
+				throw new Error('Unregistered key: ' + key);
+			var objectInitializer = factory.initializer;
+			var singleton = factory.singleton;
+			var deps = resolveDependencies(objectInitializer);
+			var instance = {};
+			instance = objectInitializer.apply(instance, deps);
+			if (singleton)
+				instances[key] = instance;
+		}
+		return instance;
+	}
+
+	function resolveDependencies(objectIntializer) {
+		var deps = [];
+		var depKeys = getFunctionParameterNames(objectIntializer);
+		for (var i = 0; i < depKeys.length; i ++) {
+			deps[i] = get(depKeys[i]);
+		}
+		return deps;
+	}
+
+	function register(key, objectInitializer) {
+		factories[key] = {initializer: objectInitializer, singleton: false};
+	};
+
+	function registerSingleton(key, objectInitializer) {
+		factories[key] = {initializer: objectInitializer, singleton: true};
+	};
+
+	function registerManual(key, objectInitializer) {
+		instances[key] = objectInitializer();
+	};
+
+	function getFunctionParameterNames(func) {
+		var fnStr = func.toString().replace(STRIP_COMMENTS, '');
+		var result = fnStr.slice(fnStr.indexOf('(') + 1, fnStr.indexOf(')')).match(ARGUMENT_NAMES);
+		if (result === null) {
+			result = [];
+		}
+		return result;
+	}
+
+	return {
+		get: get,
+		register: register,
+		registerManual: registerManual,
+		registerSingleton: registerSingleton,
+	};
+
+})();