export type CalendarView = "month" | "week" | "day";
export type WeekStart = 0 | 1;
export type SpanEvent = {
    /** Unique key of the event. */
    id: string;
    /** First day covered; time of day is ignored. */
    start: Date;
    /** Last day covered, inclusive; omit for a single-day event. */
    end?: Date;
    /** Event text, used as a sort tie-break when laying out lanes. */
    label: string;
};
export type WeekSegment<E extends SpanEvent> = {
    /** The event this bar draws. */
    event: E;
    /** First column the bar covers, clamped to the week. */
    startCol: number;
    /** Last column the bar covers, clamped to the week. */
    endCol: number;
    /** Row index of the bar; lanes at or past `maxLanes` are counted in `hiddenByCol`, not drawn. */
    lane: number;
    /** True when the event began in an earlier week. */
    continuesBefore: boolean;
    /** True when the event runs into a later week. */
    continuesAfter: boolean;
};
export type WeekLayout<E extends SpanEvent> = {
    /** Every bar for the week, including those in hidden lanes. */
    segments: WeekSegment<E>[];
    /** Number of lanes to draw, capped at `maxLanes`. */
    visibleLanes: number;
    /** Per column, how many events fall in lanes that are not drawn. */
    hiddenByCol: number[];
};
export declare const startOfDay: (d: Date) => Date;
export declare const addDays: (d: Date, n: number) => Date;
export declare const addMonths: (d: Date, n: number) => Date;
export declare const isSameDay: (a: Date, b: Date) => boolean;
export declare const dayKey: (d: Date) => string;
export declare const isWeekend: (d: Date) => boolean;
/** Whole calendar days from `a` to `b`, counted on date components so a DST day is still one day. */
export declare const diffDays: (a: Date, b: Date) => number;
export declare const startOfWeek: (d: Date, weekStartsOn: WeekStart) => Date;
export declare const weekDays: (d: Date, weekStartsOn: WeekStart) => Date[];
/** Whole weeks that cover the month of `d`, padded with the neighbouring months' days. */
export declare const monthWeeks: (d: Date, weekStartsOn: WeekStart) => Date[][];
export declare const visibleWeeks: (view: CalendarView, d: Date, weekStartsOn: WeekStart) => Date[][];
export declare const shiftAnchor: (view: CalendarView, d: Date, direction: 1 | -1) => Date;
export declare const eventRange: (e: Pick<SpanEvent, "start" | "end">) => {
    start: Date;
    end: Date;
};
export declare const eventsOnDay: <E extends SpanEvent>(events: readonly E[], day: Date) => E[];
/** Lays events out in lanes across one week row; lanes past `maxLanes` are counted per column, not drawn. */
export declare const layoutWeek: <E extends SpanEvent>(days: readonly Date[], events: readonly E[], maxLanes: number) => WeekLayout<E>;
export type NavKey = "ArrowLeft" | "ArrowRight" | "ArrowUp" | "ArrowDown" | "Home" | "End" | "PageUp" | "PageDown";
export declare const NAV_KEYS: readonly string[];
export declare const isNavKey: (key: string) => key is NavKey;
export declare const moveFocus: (view: CalendarView, d: Date, key: NavKey, weekStartsOn: WeekStart) => Date;
export declare const weekdayLabels: (locale: string | undefined, weekStartsOn: WeekStart, style?: "short" | "long") => string[];
export declare const formatTitle: (view: CalendarView, d: Date, locale: string | undefined, weekStartsOn: WeekStart) => string;
export declare const formatFullDate: (d: Date, locale: string | undefined) => string;