export interface BsDayCell {
    /** BS day number, 1-based. */
    day: number;
    /** Full BS key, e.g. "2082-04-15". */
    bsKey: string;
    /** AD equivalent (yyyy-MM-dd). */
    adDate: string;
    /** JS day number 0=Sun…6=Sat of the AD equivalent. */
    weekday: number;
    /** True for Saturday/Sunday (or the configured weekend set). */
    weekend: boolean;
    /** Rich event records from `Events/<year>.json`, if any. */
    events: import("../types").CalendarEvent[];
    /** True when the day equals the supplied `today` key. */
    today: boolean;
}
export interface BsMonthGrid {
    year: number;
    month: number;
    /** 0=Sun…6=Sat weekday of day 1 (AD equivalent). */
    leadingBlanks: number;
    cells: BsDayCell[];
}
/** English + Nepali month names, matching the converter's canonical lists. */
export declare function monthNames(locale?: "en" | "ne"): readonly string[];
/** Days in a BS month from the published month lengths; null when unknown. */
export declare function daysInBsMonth(year: number, month: number): number | null;
/**
 * Builds the grid for one BS month. Resolves leading blanks from the AD
 * weekday of day 1 and tags each cell with weekend + event flags. Events
 * failing to load (a year with no `Events/<year>.json`) degrade to
 * weekend-only marking rather than throwing.
 */
export declare function buildMonthGrid(year: number, month: number, todayBsKey?: string): Promise<BsMonthGrid>;
/** Formats a BS key the way humans read it: "15 Shrawan 2082". */
export declare function formatBsLong(bsKey: string, locale?: "en" | "ne"): string;
/** Today's BS key (yyyy-M-d) from an AD instant, or undefined when unsupported. */
export declare function todayBsKey(now?: Date): Promise<string | undefined>;
/** Stable equality for BS keys regardless of zero-padding. */
export declare function sameBsDay(a: string | null | undefined, b: string | null | undefined): boolean;
/** Checks an AD yyyy-MM-dd string is a real calendar date. */
export declare function isAdKey(key: string): boolean;