((window) => {
	const moduleCache = {};
	const exportsCache = {};
	const exportsPlaceholder = '!exports';

	function define(name, deps, fn) {
		if (Array.isArray(name)) {
			if (typeof (deps) === 'function') {
				const resolvedDeps = require(name);
				deps.apply(null, resolvedDeps);
			}
			return;
		}

		moduleCache[name] = {deps, fn};
	}

	function require(names) {
		return (names || [])
			.map((name) => {
				if (name in exportsCache) {
					return exportsCache[name];
				}
				if (name === 'exports') {
					return exportsPlaceholder;
				}

				const mod = moduleCache[name];
				if (!mod) {
					throw new Error(`Unknown module "${name}"`);
				}

				exportsCache[name] = {};
				const args = require(mod.deps);
				const index = args.findIndex(x => x === exportsPlaceholder);
				if (index !== -1) {
					args[index] = exportsCache[name];
				}
				mod.fn.apply(null, args);
				const moduleKey = '__$module';
				if (exportsCache[name][moduleKey]) {
					exportsCache[name] = exportsCache[name][moduleKey];
				}
				return exportsCache[name];
			});
	}

	window.require = exportsCache.require = require;
	window.define = define;
	window.exportsCache = exportsCache;
	window.moduleCache = moduleCache;
})(window);