/**
 * Text normalizer — comprehensive l33t speak decoder, diacritics stripper,
 * separator remover, and obfuscation handler.
 *
 * Algorithm: Single-pass greedy longest-match for multi-char sequences,
 * followed by single-char substitution, repeat collapse, and separator strip.
 *
 * Performance: O(n) for single-char, O(n * maxSeqLen) for multi-char where
 * maxSeqLen is bounded at 4. Pre-sorted sequences by length (longest first)
 * ensure greedy matching is correct.
 */
/**
 * Fold Unicode obfuscations into ASCII-equivalent forms while tracking the
 * original-string index of every output character. This is the front door for
 * detection: tokenization and matching run on the folded text, then result
 * positions are mapped back to the original via the returned indexMap.
 *
 * Folds applied (per codepoint):
 *  - Confusables: Cyrillic/Greek letters that visually impersonate Latin
 *    (e.g. Cyrillic 'а' U+0430 → 'a').
 *  - NFKC compatibility decomposition: fullwidth (Ｆｕｃｋ → Fuck),
 *    mathematical alphanumeric (𝐟𝐮𝐜𝐤 → fuck), ligatures (fi → fi), etc.
 *
 * The indexMap has length `folded.length + 1`. For any folded slice
 * [start, end), the corresponding original slice is
 * [indexMap[start], indexMap[end]).
 *
 * Fast path: pure-ASCII input returns an identity index map without entering
 * the per-codepoint loop. Callers that already detect ASCII can skip this
 * entirely.
 */
export declare function unicodeFold(input: string): {
    text: string;
    indexMap: number[];
};
/**
 * Normalize a string by applying all transformations.
 * Returns the cleaned, lowercase form.
 *
 * Pipeline:
 * 1. Lowercase
 * 2. Strip invisible unicode
 * 3. Replace multi-char l33t sequences (greedy longest-first)
 * 4. Replace single-char substitutions
 * 5. Collapse repeated characters (3+ → 2)
 * 6. Strip separators between chars
 */
export declare function normalize(input: string): string;
/**
 * Generate multiple normalized variants for broader matching.
 */
export declare function normalizeVariants(input: string): string[];