import { type Maybe, type TimezoneAbbreviation, type TimezoneString, type TimezoneStringRef, type UTCTimezoneAbbreviation } from '@dereekb/util';
/**
 * Returns all recognized IANA timezone strings, including the explicit UTC entry.
 *
 * @returns All known IANA timezone strings plus UTC.
 *
 * @example
 * ```ts
 * const zones = allTimezoneStrings();
 * // ['Africa/Abidjan', ..., 'UTC']
 * ```
 */
export declare function allTimezoneStrings(): TimezoneString[];
/**
 * Lazily-computed set of all known timezone strings for O(1) membership checks.
 *
 * @example
 * ```ts
 * allKnownTimezoneStrings().has('America/New_York'); // true
 * ```
 */
export declare const allKnownTimezoneStrings: import("@dereekb/util").CachedFactoryWithInput<Set<string>, unknown>;
/**
 * Lazily-computed array of {@link TimezoneInfo} for every known timezone.
 *
 * Abbreviations are resolved at the time of first access, so results reflect
 * the DST state at that moment.
 */
export declare const allTimezoneInfos: import("@dereekb/util").CachedFactoryWithInput<TimezoneInfo[], unknown>;
/**
 * Pre-computed timezone metadata used for display and search operations.
 *
 * Contains lowercase and search-friendly string variants so that
 * {@link searchTimezoneInfos} can perform fast case-insensitive matching.
 */
export interface TimezoneInfo extends TimezoneStringRef {
    /**
     * Searchable form with slashes/underscores replaced by spaces and lowercased.
     */
    readonly search: string;
    /**
     * Lowercased IANA timezone identifier.
     */
    readonly lowercase: string;
    /**
     * Short abbreviation (e.g., `"EST"`, `"PDT"`).
     */
    readonly abbreviation: string;
    /**
     * Lowercased abbreviation for case-insensitive matching.
     */
    readonly lowercaseAbbreviation: string;
}
/**
 * Returns the {@link TimezoneInfo} for the current system timezone, falling back to UTC.
 *
 * @returns Timezone info for the current system timezone.
 *
 * @example
 * ```ts
 * const info = timezoneInfoForSystem();
 * console.log(info.abbreviation); // e.g., 'CST'
 * ```
 */
export declare function timezoneInfoForSystem(): TimezoneInfo;
/**
 * Returns the short abbreviation (e.g., `"EST"`, `"PDT"`) for the given timezone at the specified date.
 *
 * The date matters because abbreviations change with DST transitions.
 * Returns `"UNKNOWN"` if no timezone is provided.
 *
 * @param timezone - IANA timezone string (or UTC abbreviation) whose abbreviation should be returned.
 * @param date - Reference moment used to evaluate the abbreviation; defaults to the current date/time.
 * @returns Short timezone abbreviation for the resolved moment.
 *
 * @example
 * ```ts
 * getTimezoneAbbreviation('America/New_York'); // 'EST' or 'EDT'
 * ```
 */
export declare function getTimezoneAbbreviation(timezone: Maybe<TimezoneString | UTCTimezoneAbbreviation>, date?: Date): TimezoneAbbreviation;
/**
 * Returns the full display name (e.g., `"Eastern Standard Time"`) for the given timezone.
 *
 * Returns `"Unknown Timezone"` if no timezone is provided.
 *
 * @param timezone - IANA timezone string whose display name should be returned.
 * @param date - Reference moment used to evaluate the name; defaults to the current date/time.
 * @returns Full timezone display name for the resolved moment.
 *
 * @example
 * ```ts
 * getTimezoneLongName('America/New_York'); // 'Eastern Standard Time'
 * ```
 */
export declare function getTimezoneLongName(timezone: Maybe<TimezoneString>, date?: Date): string;
/**
 * Builds a {@link TimezoneInfo} for the given timezone, computing abbreviation and search variants.
 *
 * @param timezone - IANA timezone string whose info should be built.
 * @param date - Reference moment used to evaluate the abbreviation; defaults to the current date/time.
 * @returns Computed TimezoneInfo with abbreviation and search variants.
 *
 * @example
 * ```ts
 * const info = timezoneStringToTimezoneInfo('America/Chicago');
 * // info.abbreviation => 'CST' or 'CDT'
 * // info.search => 'america chicago'
 * ```
 */
export declare function timezoneStringToTimezoneInfo(timezone: TimezoneString, date?: Date): TimezoneInfo;
/**
 * Filters timezone infos by a search string, matching against the searchable name,
 * lowercase identifier, and abbreviation.
 *
 * For queries longer than 2 characters, substring matching on the searchable name is also used.
 *
 * @param search - Search query supplied by the caller.
 * @param infos - TimezoneInfo entries to filter.
 * @returns Entries whose searchable fields match the query.
 *
 * @example
 * ```ts
 * const results = searchTimezoneInfos('eastern', allTimezoneInfos());
 * ```
 */
export declare function searchTimezoneInfos(search: string, infos: TimezoneInfo[]): TimezoneInfo[];
/**
 * Converts a timezone identifier into a lowercase, space-separated string for search indexing.
 *
 * Replaces `/` and `_` with spaces (e.g., `"America/New_York"` becomes `"america new york"`).
 *
 * @param timezone - The IANA timezone string to convert.
 * @returns The searchable lowercase string.
 *
 * @example
 * ```ts
 * timezoneStringToSearchableString('America/New_York'); // 'america new york'
 * ```
 */
export declare function timezoneStringToSearchableString(timezone: TimezoneString): string;
/**
 * Checks whether the input string is a recognized IANA timezone identifier.
 *
 * Uses the cached set from {@link allKnownTimezoneStrings} for O(1) lookup.
 *
 * @param input - Candidate string to test against the registry.
 * @returns Whether the input matches a known IANA timezone identifier.
 *
 * @example
 * ```ts
 * isKnownTimezone('America/New_York'); // true
 * isKnownTimezone('Mars/Olympus');     // false
 * ```
 */
export declare function isKnownTimezone(input: string | TimezoneString): boolean;