import { Engine, BodyId, Zodiac } from "./chart.js";
export type RiseKind = "rise" | "set" | "mtransit" | "itransit";
export interface RiseSetOptions {
    altM?: number;
    pressure?: number;
    tempC?: number;
    searchDays?: number;
    /** Rise/set of the disc center instead of the upper limb. */
    discCenter?: boolean;
}
/**
 * The next rise, set, or meridian transit of a body after `jdStart`, as a
 * Julian Day (UT). Accounts for the body's apparent radius, atmospheric
 * refraction, and observer altitude.
 *
 * @param engine The engine used to evaluate positions.
 * @param body A body id from {@link Engine.bodies}.
 * @param jdStart Search start, Julian Day (UT). The result is the first event
 *   strictly after this instant.
 * @param latDeg Observer latitude in degrees, north positive.
 * @param lonDeg Observer longitude in degrees, east positive.
 * @param kind `"rise"`, `"set"`, `"mtransit"` (upper/meridian transit), or
 *   `"itransit"` (lower transit). Defaults to `"rise"`.
 * @param opts `altM` (observer altitude, m), `pressure` (hPa), `tempC`, and
 *   `searchDays` (how far ahead to look; defaults to 2).
 * @returns The event time as a Julian Day (UT), or `null` when it does not
 *   occur in the window (e.g. polar day or night).
 * @example
 * ```ts
 * // Next sunrise over London after 2025-06-01
 * const jd = riseSet(engine, "sun", julianDay(2025, 6, 1), 51.5, -0.13, "rise");
 * ```
 */
export declare function riseSet(engine: Engine, body: BodyId, jdStart: number, latDeg: number, lonDeg: number, kind?: RiseKind, opts?: RiseSetOptions): number | null;
/** UT JDs where the body's apparent longitude crosses targetLon (degrees)
 *  in [jdStart, jdEnd]. Retrograde bodies can cross a degree three times;
 *  every crossing is returned in time order. */
export declare function crossings(engine: Engine, body: BodyId, targetLon: number, jdStart: number, jdEnd: number, zodiac?: Zodiac, maxHits?: number): number[];
export type PhaseName = "new" | "first_quarter" | "full" | "last_quarter";
/**
 * Every principal lunar phase (new, first quarter, full, last quarter) within
 * `[jdStart, jdEnd]`, sorted by time. Found from the Sun–Moon elongation
 * crossing 0°/90°/180°/270°.
 *
 * @param engine The engine used to evaluate positions.
 * @param jdStart Start of the window, Julian Day (UT).
 * @param jdEnd End of the window, Julian Day (UT).
 * @param maxHits Cap on the number of phases returned. Defaults to 60.
 * @returns Sorted `[jdUt, phase]` pairs, where `phase` is one of
 *   {@link PhaseName}.
 * @example
 * ```ts
 * const phases = lunarPhases(engine, julianDay(2025, 1, 1), julianDay(2025, 2, 1));
 * // [[jd, "new"], [jd, "first_quarter"], ...]
 * ```
 */
export declare function lunarPhases(engine: Engine, jdStart: number, jdEnd: number, maxHits?: number): Array<[number, PhaseName]>;
/** Times the body stations (speed crosses zero): [jdUt, direction the body
 *  turns]. Sun and Moon never station. Station timing is ill-conditioned:
 *  expect minute-level differences between ephemerides. */
export declare function stations(engine: Engine, body: BodyId, jdStart: number, jdEnd: number, maxHits?: number): Array<[number, "retrograde" | "direct"]>;
/**
 * The Gauquelin sector of a body (1–36, fractional) from the rise/set times of
 * the disc centre with refraction (Swiss Ephemeris method 3). Sectors run from
 * rise: 1–18 above the horizon, 19–36 below.
 *
 * @param engine The engine used to evaluate positions.
 * @param body A body id from {@link Engine.bodies}.
 * @param jdUt Julian Day (UT).
 * @param latDeg Observer latitude in degrees, north positive.
 * @param lonDeg Observer longitude in degrees, east positive.
 * @returns The sector in `[1, 37)`, or `null` in polar no-rise/no-set
 *   conditions.
 */
export declare function gauquelinSector(engine: Engine, body: BodyId, jdUt: number, latDeg: number, lonDeg: number): number | null;