export type ThreadRef = {
    /** Thread manufacturer + line, e.g. "Madeira Polyneon". */
    brand: string;
    /** Manufacturer catalog number the operator uses to pull the cone. */
    code: string;
    name: string;
    hex: string;
};
export type PantoneMatch = {
    /** What the customer asked for, e.g. "PMS 186 C" or "#c8102e". */
    requested: string;
    /** Screen-approximate color of the request. */
    requestedHex: string;
    /** Closest stocked thread — final match is confirmed at digitizing. */
    thread: ThreadRef;
};
export type NearestPantone = {
    /** Display code, e.g. "PMS 186 C" or "PMS WARM RED". */
    code: string;
    /** Screen-approximate sRGB hex of the matched swatch. */
    hex: string;
    /** Euclidean sRGB distance from the input — 0 is an exact table hit. */
    distanceRgb: number;
};
export type PantoneMatchQuality = "exact" | "close" | "approximate";
type Rgb = [number, number, number];
export declare const hexToRgb: (hex: string) => Rgb;
export declare const isThreadRef: (value: unknown) => value is ThreadRef;
export declare const isPantoneMatch: (value: unknown) => value is PantoneMatch;
/**
 * Nearest stocked thread by RGB distance — the same mapping a digitizer does
 * against the thread rack. Drives stitch-preview quantization and the
 * auto-extracted thread sequence on the work order.
 */
export declare const nearestThread: (catalog: ThreadRef[], red: number, green: number, blue: number) => ThreadRef;
export declare const threadByHex: (catalog: ThreadRef[], hex: string) => ThreadRef | null;
export declare const PMS_APPROX: Record<string, string>;
/**
 * Nearest PMS_APPROX swatch by RGB distance to a hex color — the reverse of
 * resolveThreadQuery, used to label an arbitrary artwork color with the
 * closest common Pantone code. Returns null when the input is not a hex
 * color. Screen approximation only — final ink match is confirmed against a
 * physical Pantone book.
 */
export declare const nearestPantone: (hex: string) => NearestPantone | null;
export declare const pantoneMatchQuality: (distanceRgb: number) => PantoneMatchQuality;
/**
 * Resolve a customer color request — a hex value or a common PMS code —
 * to the nearest stocked thread. Returns null when the input is neither a
 * hex color nor a PMS number in the built-in table.
 */
export declare const resolveThreadQuery: (catalog: ThreadRef[], input: string) => PantoneMatch | null;
export {};