import { AppConfigService } from '../../services/app-config.service';
import * as i0 from "@angular/core";
export interface IDataItem {
    date: string;
    currentMonth?: boolean;
    dateValue: Date;
}
export interface IDataRow {
    items: IDataItem[];
    mixed: boolean;
}
export interface ICalendarBody {
    rows: IDataRow[];
}
export interface IDecadeYearsObject {
    title: string;
    items: number[][];
}
export interface IMonthIdentity {
    year: number;
    monthIndex: number;
}
export interface IDateRange {
    startDate: Date;
    endDate: Date;
}
export type TimeZoneId = {
    raw: string;
    canonical: string;
};
export declare class CoreDatetimeService {
    acs: AppConfigService;
    timeZoneOffset: any;
    $knownTimeZones: import("@angular/core").WritableSignal<string[]>;
    constructor();
    loadKnownTimezoneIdentifiers(): void;
    getMonthText(lang: string, monthIndex: number): string;
    dateToVnString(date: Date): string;
    dateToLocalizedString(value: Date, lang: string): string;
    private getOrdinalSuffix;
    getShortWeekdays(lang: string): any;
    getWeekdays(lang: string): any;
    getMonthNames(lang: string): any;
    private getMonoCalendarBody;
    getCalendarBody(year: number, monthIndex: number, direction?: number): ICalendarBody;
    getLastDateOfMonth(year: number, monthIndex: number): Date;
    getDecadeYearsObject(currentYear: number): IDecadeYearsObject;
    isDateString(date: string): boolean;
    monthIdentityToMonthString(monthIdentity: IMonthIdentity): string;
    dateToMonthString(date: Date): string;
    /**
     * Interprets a Date as a civil calendar date in a specific IANA timezone.
     *
     * Purpose:
     * - Given an absolute instant (JavaScript Date),
     *   re-interpret it as a calendar date (YYYY-MM-DD)
     *   as perceived in the provided IANA timezone.
     *
     * What this function DOES:
     * - Uses Intl.DateTimeFormat with `timeZone` to extract
     *   year / month / day in the target timezone.
     * - Re-materializes a new Date using those calendar parts
     *   in the browser's local runtime timezone.
     *
     * What this function DOES NOT do:
     * - Does NOT apply business rules (e.g. start-of-day / end-of-day).
     * - Does NOT modify hours, minutes, seconds explicitly.
     * - Does NOT depend on range semantics (start / inclusive-end).
     * - Does NOT mutate the input Date.
     *
     * Design notes:
     * - JavaScript Date always represents an absolute instant.
     * - "Date-only" values in business forms are civil concepts,
     *   not instants in time.
     * - Timezone interpretation MUST be applied exactly once,
     *   at form boundaries (e.g. writeValue / onChange).
     *
     * Usage constraints:
     * - This function is intended for form-layer normalization only.
     * - It MUST be optional and backward-compatible.
     * - Absence of timezone context MUST preserve legacy behavior.
     *
     * @param date Absolute Date (instant)
     * @param timezoneId IANA Time Zone ID (e.g. "Asia/Ho_Chi_Minh")
     * @returns Date representing the same civil day in local runtime timezone
     */
    interpretDateInTimezone(date: Date, timezoneId: string): Date;
    canonicalizeTimeZone(tz: string): string;
    static ɵfac: i0.ɵɵFactoryDeclaration<CoreDatetimeService, never>;
    static ɵprov: i0.ɵɵInjectableDeclaration<CoreDatetimeService>;
}