import type { PostgresJsDatabase } from "drizzle-orm/postgres-js";
export interface SlotUnitAvailability {
    optionUnitId: string;
    unitName: string;
    occupancyMax: number | null;
    /** option_units.max_quantity — `null` when no cap is configured. */
    initial: number | null;
    /** Active reservations against this unit on this slot. */
    reserved: number;
    /** `initial - reserved`, or `null` when the pool is unlimited. */
    remaining: number | null;
}
/**
 * Returns per-option-unit availability for a slot. `reserved` is derived from
 * `booking_items` on active bookings that point at this slot via
 * `metadata.availabilitySlotId` (stamped by the product→booking convert flow)
 * and from the corresponding `option_unit_id` column.
 *
 * Returns `null` when the slot does not exist. The slot must have an
 * `optionId` for per-unit breakdown to make sense; when it's absent, the
 * result is an empty array.
 */
export declare function getSlotUnitAvailability(db: PostgresJsDatabase, slotId: string): Promise<SlotUnitAvailability[] | null>;