/**
 * SPDX-License-Identifier: CC0-1.0
 *
 * Copyright (C) 2026 Woj. Kosior <koszko@koszko.org>
 */

/*
  #+begin_src manifest-jq
  .matches = ["<all_urls>"]
  #+end_src
*/

if (false) { /* #+begin_src background-js */
    blockJsOnCookie(/^pow_challenge=[0-9]{12}[.]/);
} /* #+end_src */

/*
 * Solve "Varnish PoW" challenges.  These are used in some places under
 * *.debian.org and are derived from haphash PoW challenges.  We utilize
 * `pow-solver.js' for computing the hashes and
 * `appended-number-counting-schemes.js' for the counting scheme.
 */

(() => {

const target = new URLSearchParams(window.location.search).get('original');
const match = /(?:^|;)\s*pow_challenge=(\S*)/.exec(document.cookie);
if (target && match && !window.location.href.startsWith("file://")) {
    document.documentElement.innerHTML = `\
<p style="margin: 1em auto; max-width: 600px; text-align: center;">
    Simple extension is trying to solve a Varnish PoW challenge on this page…
</p>
`;

    const challenge = match[1];
    /* A fixed length of 8 zero bits is required by this challenge. */
    genericSolvePow(challenge + ';', 8, appendedNumberCountingSchemes)
        .then(({suffixArray}) => {
            const nonce = new TextDecoder().decode(suffixArray);
            document.cookie = `pow_nonce=${nonce}; Path=/`;
            window.location.href = target;
        });
}

})();