"use strict";

const { validateArguments, required } = require("@validatem/core");
const isString = require("@validatem/is-string");
const isRegularExpression = require("@validatem/is-regular-expression");

module.exports = function matchOrError(regex, string) {
	validateArguments(arguments, [
		[ "regex", required, isRegularExpression ],
		[ "string", required, isString ]
	]);
	
	let match = regex.exec(string);

	if (match == null) {
		throw new Error(`Regular expression ${regex.toString()} failed to match on string: ${string}`);
	} else {
		// NOTE: Follows `execall` format: https://www.npmjs.com/package/execall
		return {
			match: match[0],
			subMatches: match.slice(1),
			index: match.index
		};
	}
};