// How the import finder asks when it is not ALLOWED to ask.
//
// The Soulseek server drops a search outright when the query carries every
// word of one of its excluded phrases. Measured 2026-08-11 against the live
// server, with the record's own copies provably on the network:
//
//   animal collective merriweather        578 peers · 2,664 FLAC files
//   merriweather pavilion                 683 peers
//   post pavilion                         712 peers
//   merriweather post pavilion              0 peers   <- every time
//   pavilion merriweather post              0 peers   <- order is irrelevant
//   merriweather post pavilion flac         0 peers   <- extra terms don't help
//
// The published exclusions behave identically ("village people" 0, "bryan
// adams" 0, "village people flac" 0, while "abba gold" answers with 608), so
// this is that same mechanism — but the server publishes only SOME of its
// list. `sanitizeSearchQuery` strips the phrases it does publish; an
// unpublished one like this album's title reaches the wire and is swallowed.
//
// Nothing here can make the server answer a refused query. What it CAN do is
// ask a shorter question the server does answer, and then apply the part we
// were not allowed to say to the answers, where no server is involved.

const STOPWORDS = new Set(["the", "a", "an", "and", "or", "of", "in", "on", "at", "to", "for", "with"]);

/** Words, punctuation folded away. `&` and `-` are separators, not letters, so
 *  "Rock & Roll" and "Rock-n-Roll" both yield asking words rather than one
 *  token nothing will match. */
export function queryWords(s) {
    return String(s ?? "")
        .toLowerCase()
        .replace(/[^\p{L}\p{N}]+/gu, " ")
        .split(/\s+/)
        .filter(Boolean);
}

/** The record's name with its last word dropped — the shortest change that
 *  breaks the refused word-set while still naming the record.
 *
 *  Trailing stopwords go with it: "The Dark Side of the Moon" without "moon"
 *  is "the dark side of the", which asks the network for three words that
 *  carry no meaning and narrow the result set for nothing.
 *
 *  Returns "" when there is nothing left worth asking. A one-word name
 *  shortens to nothing at all, and a bare artist query asks the network for
 *  that artist's entire discography — the same thing `findQueries` refuses
 *  to do. */
export function shortenName(name) {
    const w = queryWords(name);
    if (w.length < 2) return "";
    w.pop();
    while (w.length && STOPWORDS.has(w[w.length - 1])) w.pop();
    return w.join(" ");
}

/** Does this peer's path claim to BE the record we could not ask for? Every
 *  word of the full name has to appear in it.
 *
 *  This is the half of the question the server was not allowed to answer, and
 *  it is what keeps the shortened query honest: "animal collective merriweather
 *  post" also matches a live set recorded AT Merriweather Post Pavilion, and
 *  the venue is in the path of every bootleg taped there.
 *
 *  Deliberately whole-word, not substring: "Pavillion" is not "Pavilion", and
 *  a folder that misspells the record is refused rather than guessed at. That
 *  costs a few real copies whose owners cannot spell; accepting near-misses
 *  costs correctness, and there is no way to tell the two apart from here. */
export function pathHasTitle(path, name) {
    const need = queryWords(name);
    if (!need.length) return false;
    const have = new Set(queryWords(path));
    return need.every((w) => have.has(w));
}