util.js

const mod = {

	isEtag0: string => !string.match(/\D/i),
	isEtag1: string => string.trim().length && string.match(/^([^']|\\')*/i),
	validEtag: version => version === 0 ? mod.isEtag0 : mod.isEtag1,

	isName0: string => string.match(/[a-zA-Z0-9%-_]/i),
	isName1: string => string.trim().length && string.match(/[a-zA-Z0-9%-_\.\-\_]/i),
	validName: version => version === 0 ? mod.isName0 : mod.isName1,
  
	validDate: text => text.match(/^(Mon|Tue|Wed|Thu|Fri|Sat|Sun), \d{2} (Jan|Feb|Mar|Apr|May|Jun|Jul|Aug|Sep|Oct|Nov|Dec) \d{4} \d{2}:\d{2}:\d{2} GMT$/),

	clone: object => Object.assign({}, object),

	webfinger: {

		async discover (server, account) {
			const params = {
				resource: `acct:${ account }@${ (new URL(server)).hostname }`,
			};

			const json = await (await mod._fetch(`${ server }/.well-known/webfinger?${ new URLSearchParams(params) }`)).json();

			return json.links.filter(e => ['remotestorage', 'http://tools.ietf.org/id/draft-dejong-remotestorage'].includes(e.rel)).shift();
		},

		version: link => parseInt((link.type || link.properties['http://remotestorage.io/spec/version']).match(/draft-dejong-remotestorage-(\d+)/).pop()),

		auth: link => link.properties['auth-endpoint'] || link.properties['http://tools.ietf.org/html/rfc6749#section-4.2'],

	},

	_fetch () {
		// console.log([...arguments]);
		return fetch(...arguments);
	},

	_url: (State, path) => `${ State.baseURL }${ `${ State.scope ? '/' + State.scope : '' }/${ path }`.replace(/\/+/g, '/') }`,

	storage (State) {
		const headers = {
			'Content-Type': 'application/json',
		};

		if (State.token)
			headers['Authorization'] = `Bearer ${ State.token }`;

		return {
			get: (path, _headers = {}) => mod._fetch(mod._url(State, path), {
				headers: Object.assign(mod.clone(headers), _headers),
			}),
			put: (path, body, _headers = {}) => mod._fetch(mod._url(State, path), {
				headers: Object.assign(mod.clone(headers), _headers),
				method: 'PUT',
				body: JSON.stringify(_headers).includes('charset=binary') ? body : JSON.stringify(body),
			}),
			delete: (path, _headers = {}) => mod._fetch(mod._url(State, path), {
				headers: Object.assign(mod.clone(headers), _headers),
				method: 'DELETE',
			}),
			head: path => mod._fetch(mod._url(State, path), {
				headers,
				method: 'HEAD',
			}),
			options: (path, _headers = {}) => mod._fetch(mod._url(State, path), {
				headers: Object.assign(mod.clone(headers), _headers),
				method: 'OPTIONS',
			}),
		};
	},

	byteLength: input => typeof Buffer !== 'undefined' ? Buffer.from(input).length : new TextEncoder().encode(input).byteLength,

};

export default mod;