import { URISchemeHandler, URIComponents, URIOptions } from '../uri';
import { pctEncChar, SCHEMES } from '../uri';

export interface URNComponents extends URIComponents {
	nid?:string;
	nss?:string;
}

export interface URNOptions extends URIOptions {
	nid?:string;
}

const NID$ = '(?:[0-9A-Za-z][0-9A-Za-z\\-]{1,31})';
const PCT_ENCODED$ = '(?:\\%[0-9A-Fa-f]{2})';
const TRANS$$ = '[0-9A-Za-z\\(\\)\\+\\,\\-\\.\\:\\=\\@\\;\\$\\_\\!\\*\\\'\\/\\?\\#]';
const NSS$ = '(?:(?:' + PCT_ENCODED$ + '|' + TRANS$$ + ')+)';
const URN_SCHEME = new RegExp('^urn\\:(' + NID$ + ')$');
const URN_PATH = new RegExp('^(' + NID$ + ')\\:(' + NSS$ + ')$');
const URN_PARSE = /^([^\:]+)\:(.*)/;
const URN_EXCLUDED = /[\x00-\x20\\\"\&\<\>\[\]\^\`\{\|\}\~\x7F-\xFF]/g;

// RFC 2141
const handler:URISchemeHandler<URNComponents,URNOptions> = {
	scheme : 'urn',

	parse : function (components:URIComponents, options:URNOptions):URNComponents {
		const matches = components.path && components.path.match(URN_PARSE);
		let urnComponents = components as URNComponents;

		if (matches) {
			const scheme = options.scheme || urnComponents.scheme || 'urn';
			const nid = matches[1].toLowerCase();
			const nss = matches[2];
			const urnScheme = `${scheme}:${options.nid || nid}`;
			const schemeHandler = SCHEMES[urnScheme];

			urnComponents.nid = nid;
			urnComponents.nss = nss;
			urnComponents.path = undefined;

			if (schemeHandler) {
				urnComponents = schemeHandler.parse(urnComponents, options) as URNComponents;
			}
		} else {
			urnComponents.error = urnComponents.error || 'URN can not be parsed.';
		}

		return urnComponents;
	},

	serialize : function (urnComponents:URNComponents, options:URNOptions):URIComponents {
		const scheme = options.scheme || urnComponents.scheme || 'urn';
		const nid = urnComponents.nid;
		const urnScheme = `${scheme}:${options.nid || nid}`;
		const schemeHandler = SCHEMES[urnScheme];

		if (schemeHandler) {
			urnComponents = schemeHandler.serialize(urnComponents, options) as URNComponents;
		}

		const uriComponents = urnComponents as URIComponents;
		const nss = urnComponents.nss;
		uriComponents.path = `${nid || options.nid}:${nss}`;

		return uriComponents;
	},
};

export default handler;