// Ported and adapted from js-yaml-js-types v1.0.0:
// https://github.com/nodeca/js-yaml-js-types/tree/ac537e7bbdd3c2cbbd9882ca3919c520c2dc022b
// Copyright 2011-2015 by Vitaly Puzrin. All rights reserved. MIT license.
// Copyright 2018-2025 the Deno authors. MIT license.
const REGEXP = /^\/(?<regexp>[\s\S]+)\/(?<modifiers>[gismuy]*)$/;
export const regexp = {
    tag: "tag:yaml.org,2002:js/regexp",
    kind: "scalar",
    resolve(data) {
        if (data === null || !data.length)
            return false;
        if (data.charAt(0) === "/") {
            // Ensure regex is properly terminated
            const groups = data.match(REGEXP)?.groups;
            if (!groups)
                return false;
            // Check no duplicate modifiers
            const modifiers = groups.modifiers ?? "";
            if (new Set(modifiers).size < modifiers.length)
                return false;
        }
        return true;
    },
    construct(data) {
        const { regexp = data, modifiers = "" } = data.match(REGEXP)?.groups ?? {};
        return new RegExp(regexp, modifiers);
    },
    predicate: (object) => object instanceof RegExp,
    represent: (object) => object.toString(),
};
