/**
 * The date format used as an input value. Either a date or an ISO8601 string.
 */
type DateInput = Date | string;
/**
 * The date format used as a maybe input value. Either a date, ISO8601 string or null for current time
 */
type MaybeDateInput = DateInput | null;
/**
 * Format parts with text names use these descriptors:
 */
type NamedFormatOption = "long" | "short" | "narrow";
/**
 * Extended part types that include custom tokens not in Intl.DateTimeFormatPartTypes.
 */
type ExtendedPartTypes = Intl.DateTimeFormatPartTypes | "fractionalSecond";
/**
 * A registry of named format parts. Each type of part has every option.
 */
interface NamedFormats {
    weekday: Record<string, NamedFormatOption>;
    month: Record<string, NamedFormatOption>;
    dayPeriod: Record<string, NamedFormatOption>;
}
/**
 * Internal format for "pieces" of a date form. Each part represents a single
 * logical grouping, like "month", or "seconds".
 */
interface Part {
    /**
     * An object of partName to partValue For example:
     * ```js
     * { hour: '2-digit' }
     * ```
     */
    option: FormatPattern[1];
    /**
     * The name of the part, these must be valid parts of a date format as
     * specified in Intl.DateTimeFormatPartTypes, plus custom extensions.
     * Valid values are: day, dayPeriod, era, hour, literal, minute, month,
     * second, timeZoneName, weekday, year, fractionalSecond
     */
    partName: ExtendedPartTypes;
    /**
     * The value of a given part. For example "2-digit", or "narrow".
     */
    partValue: string;
    /**
     * The string token that represents the regex. For example "YYYY".
     */
    token: string;
    /**
     * A regular expression if the above token.
     */
    pattern: RegExp;
    /**
     * Does this part require a the hour12 clock.
     */
    hour12: boolean;
}
/**
 * A date part with an actual value applied.
 */
type FilledPart = Part & {
    value: string;
};
/**
 * A tuple describing a given formatting token.
 */
type FormatPattern = [
    pattern: FormatToken | string,
    option: Partial<Record<ExtendedPartTypes, string>>,
    exp?: RegExp
];
/**
 * Possible options for a format style.
 */
type FormatStyle = "full" | "long" | "medium" | "short";
/**
 * Possible objects for the dateStyle and timeStyle.
 */
type FormatStyleObj = {
    date: FormatStyle;
    time: FormatStyle;
} | {
    date: FormatStyle;
} | {
    time: FormatStyle;
};
type Format = FormatStyle | FormatStyleObj | (string & {});
/**
 * A union of all available formatting tokens.
 */
type FormatToken = "YYYY" | "YY" | "MMMM" | "MMM" | "MM" | "M" | "DD" | "D" | "dddd" | "ddd" | "d" | "mm" | "m" | "ss" | "s" | "SSS" | "HH" | "H" | "hh" | "h" | "a" | "A" | "ZZ" | "Z";
interface ParseOptions {
    /**
     * A string representing a date.
     */
    date: string;
    /**
     * The format that should be used to parse the date. This is a string composed
     * of tokens.
     */
    format: Format;
    /**
     * The locale used to parse the date.
     */
    locale: string;
    /**
     * A function that can be used to filter out parts of the format. This is
     * useful when using the native Intl formats like
     * `{ date: 'full', time: 'full' }` and not wanting to keep all the parts of
     * the given format.
     */
    partFilter?: (part: Part) => boolean;
    /**
     * The behavior to use when a date overflows a given month. For example, if
     * the date to parse is February 29, 2023 — there is no 29th day of February.
     * In this case overflow "forward" would result in March 1, 2023, "backward"
     * would result in February 28, 2023, and "throw" would throw an error.
     */
    dateOverflow?: "forward" | "backward" | "throw";
}
interface FormatOptions {
    /**
     * A date object or ISO 8601 string.
     */
    date: DateInput;
    /**
     * A format string or object.
     */
    format: Format;
    /**
     * A locale or en by default.
     */
    locale?: string;
    /**
     * Whether or not to escape literals.
     */
    genitive?: boolean;
    /**
     * A function to filter parts.
     */
    tz?: string;
    /**
     * A function to filter parts.
     */
    partFilter?: (part: Part) => boolean;
}

export type { DateInput, ExtendedPartTypes, FilledPart, Format, FormatOptions, FormatPattern, FormatStyle, FormatStyleObj, FormatToken, MaybeDateInput, NamedFormatOption, NamedFormats, ParseOptions, Part };