/**
 * @param {{
 *   sampleAt: (year: number) => {e: number, periOfDateDeg: number, equinoxLonJ2000Deg: number, generalPrecessionLonDeg: number},
 *   massLossSiderealSecondsAtYearFn: (year: number) => number,
 * }} opts
 *   sampleAt: the one-source movement sampler, keyed in the sampler's own
 *   year (Julian years from J2000 TT, 2000 = J2000; createDeepOrbitalHistory
 *   build().at wrapped by the caller — series tier where the artifact is
 *   available, mode tail beyond).
 *   massLossSiderealSecondsAtYearFn: the caller's secular mass-loss
 *   sidereal-year law, SI seconds, IAU-anchored at J2000.
 */
export function createYearLengths({ sampleAt, massLossSiderealSecondsAtYearFn }: {
    sampleAt: (year: number) => {
        e: number;
        periOfDateDeg: number;
        equinoxLonJ2000Deg: number;
        generalPrecessionLonDeg: number;
    };
    massLossSiderealSecondsAtYearFn: (year: number) => number;
}): Readonly<{
    /** Mean tropical year of date, SI seconds. @param {number} year */
    tropicalYearSecondsAtYear: (year: number) => number;
    /** Sidereal year of date, SI seconds. @param {number} year */
    siderealYearSecondsAtYear: (year: number) => number;
    /** Anomalistic year of date, SI seconds. @param {number} year */
    anomalisticYearSecondsAtYear: (year: number) => number;
    /** Axial precession period of date (equinox regression beat), JULIAN years. @param {number} y */
    axialPrecessionYearsAtYear: (y: number) => number;
    /** Perihelion (apsidal-vs-equinox) precession period of date, JULIAN years. @param {number} y */
    perihelionPrecessionYearsAtYear: (y: number) => number;
    /** Apsidal precession period of date vs the fixed stars, JULIAN years (hypersensitive: ±1 s ↔ ≈400 yr; the identifier keeps the historical "inclination" name). @param {number} y */
    inclinationPrecessionYearsAtYear: (y: number) => number;
    /** The movement's own general precession of date, ″ per Julian year (retrograde positive) — 360°/this ≡ axialPrecessionYearsAtYear to second order. @param {number} y */
    generalPrecessionArcsecPerJulianYr: (y: number) => number;
    /** The movement's own apsidal rate of date against the FIXED frame, ″ per Julian year (prograde positive) — the rate the Perihelion Longitudes Prec. cell shows for Earth; 360°/this ≡ inclinationPrecessionYearsAtYear exactly. @param {number} y */
    apsidalRateFixedArcsecPerJulianYr: (y: number) => number;
    /** The per-cardinal layer (D6 rules: year lengths λ̇-corrected; offsets/spreads raw — μs-class/second-order there). */
    cardinal: Readonly<{
        /** @param {number} y @param {'VE'|'SS'|'AE'|'WS'} type */
        yearLengthSeconds: (y: number, type: "VE" | "SS" | "AE" | "WS") => number;
        /** @param {number} y @param {'VE'|'SS'|'AE'|'WS'} type */
        eocOffsetSeconds: (y: number, type: "VE" | "SS" | "AE" | "WS") => number;
        /** @param {number} y */
        spreadSeconds: (y: number) => {
            VE: number;
            SS: number;
            AE: number;
            WS: number;
            meanSeconds: number;
        };
    }>;
    /** The planetary λ̇ ratio (diagnostic; ≡1 at J2000). */
    planetaryRelAtYear: (year: number) => number;
}>;
/** The J2000 mean tropical year, DAYS — derived in ONE home from two IAU
 *  inputs, the sidereal year and the general precession in longitude p_A
 *  (″ per JULIAN year), in the exact rate form
 *      1/T_trop = 1/T_sid + p_A / (1,296,000″ · 365.25 d)
 *  — the same beat `shorterYear` evaluates of date. 365.242190469 d on the
 *  IAU 2006 inputs. Plan 09: replaces the Meeus & Savoie 1992 input
 *  365.2421897 (66 ms shorter, whose beat with the sidereal year read
 *  25,770.7 yr against p_A's 25,771.6 — three inputs over-determining a
 *  two-parameter identity). Counting p_A per tropical or sidereal year
 *  instead moves this by 26 ms; IAU states p_A per Julian year.
 *  @param {number} siderealYearDays @param {number} generalPrecessionArcsecPerJulianYr @returns {number} */
export function computeMeanTropicalYearJ2000Days(siderealYearDays: number, generalPrecessionArcsecPerJulianYr: number): number;
/**
 * The published of-date window (plan 06 Phase 3 S2): inside |year − 2000| ≤
 * this span the one-family route is THE published year-length / precession
 * family (the banked tiers — 100-yr and 1000-yr grids, no unbounded sampler
 * growth); beyond it the published surfaces return the unit's SECULAR mean
 * (H(t)/13 for the precession period, the tidal-chain mean year), because the
 * of-date wobble is unresolved there and the deep sampler grows ~0.1 s per Myr
 * of span. A displayed rate must name its window — this is the window.
 */
export const ONE_FAMILY_WINDOW_YEARS: 2000000;