Add Luxon library and create TimeService for centralized date handling

npm/ng-packs/package.json

@@ -111,6 +111,7 @@
     "just-compare": "^2.0.0",
     "lerna": "^4.0.0",
     "lint-staged": "^13.0.0",
+    "luxon": "^3.6.1",
     "ng-packagr": "~19.1.0",
     "ng-zorro-antd": "~19.0.0",
     "nx": "~20.3.0",

npm/ng-packs/packages/core/src/lib/pipes/utc-to-local.pipe.ts

@@ -1,7 +1,6 @@
 import { Pipe, PipeTransform, Injectable, inject, LOCALE_ID } from '@angular/core';
-import { ConfigStateService, LocalizationService, TimezoneService } from '../services';
+import { ConfigStateService, LocalizationService, TimeService, TimezoneService } from '../services';
 import { getShortDateFormat, getShortDateShortTimeFormat, getShortTimeFormat } from '../utils';
-import { formatDate } from '@angular/common';
 
 @Injectable()
 @Pipe({
@@ -9,6 +8,7 @@ import { formatDate } from '@angular/common';
 })
 export class UtcToLocalPipe implements PipeTransform {
   protected readonly timezoneService = inject(TimezoneService);
+  protected readonly timeService = inject(TimeService);
   protected readonly configState = inject(ConfigStateService);
   protected readonly localizationService = inject(LocalizationService);
   protected readonly locale = inject(LOCALE_ID);
@@ -27,11 +27,9 @@ export class UtcToLocalPipe implements PipeTransform {
     try {
       if (this.timezoneService.isUtcClockEnabled) {
         const timeZone = this.timezoneService.timezone;
-        const options: Intl.DateTimeFormatOptions = { timeZone };
+        return this.timeService.formatDateWithStandardOffset(date, format, timeZone);
-        const localeStr = this.formatWithIntl(date, type, options);
-        return formatDate(localeStr, format, this.locale);
       } else {
-        return formatDate(value, format, this.locale, format);
+        return this.timeService.formatWithoutTimeZone(date, format);
       }
     } catch (err) {
       return value;
@@ -49,20 +47,4 @@ export class UtcToLocalPipe implements PipeTransform {
         return getShortDateShortTimeFormat(this.configState);
     }
   }
-
-  private formatWithIntl(
-    date: Date,
-    propType: 'date' | 'datetime' | 'time',
-    options: Intl.DateTimeFormatOptions,
-  ): string {
-    switch (propType) {
-      case 'date':
-        return date.toLocaleDateString(this.locale, options);
-      case 'time':
-        return date.toLocaleTimeString(this.locale, options);
-      case 'datetime':
-      default:
-        return date.toLocaleString(this.locale, options);
-    }
-  }
 }

npm/ng-packs/packages/core/src/lib/services/index.ts

@@ -24,3 +24,4 @@ export * from './internet-connection-service';
 export * from './local-storage-listener.service';
 export * from './title-strategy.service';
 export * from './timezone.service';
+export * from './time.service';

npm/ng-packs/packages/core/src/lib/services/time.service.ts

@@ -0,0 +1,107 @@
+import { inject, Injectable, LOCALE_ID } from '@angular/core';
+import { DateTime } from 'luxon';
+
+@Injectable({
+  providedIn: 'root',
+})
+export class TimeService {
+  private locale = inject(LOCALE_ID);
+
+  /**
+   * Returns the current date and time in the specified timezone.
+   *
+   * @param zone - An IANA timezone name (e.g., 'Europe/Istanbul', 'UTC'); defaults to the system's local timezone.
+   * @returns A Luxon DateTime instance representing the current time in the given timezone.
+   */
+  now(zone = 'local'): DateTime {
+    return DateTime.now().setZone(zone);
+  }
+
+  /**
+   * Converts the input date to the specified timezone, applying any timezone and daylight saving time (DST) adjustments.
+   *
+   * This method:
+   * 1. Parses the input value into a Luxon DateTime object.
+   * 2. Applies the specified IANA timezone, including any DST shifts based on the given date.
+   *
+   * @param value - The ISO string or Date object to convert.
+   * @param zone - An IANA timezone name (e.g., 'America/New_York').
+   * @returns A Luxon DateTime instance adjusted to the specified timezone and DST rules.
+   */
+  toZone(value: string | Date, zone: string): DateTime {
+    return DateTime.fromISO(value instanceof Date ? value.toISOString() : value, {
+      zone,
+    });
+  }
+
+  /**
+   * Formats the input date by applying timezone and daylight saving time (DST) adjustments.
+   *
+   * This method:
+   * 1. Converts the input date to the specified timezone.
+   * 2. Formats the result using the given format and locale, reflecting any timezone or DST shifts.
+   *
+   * @param value - The ISO string or Date object to format.
+   * @param format - The format string (default: 'ff').
+   * @param zone - Optional IANA timezone name (e.g., 'America/New_York'); defaults to the system's local timezone.
+   * @returns A formatted date string adjusted for the given timezone and DST rules.
+   */
+  format(value: string | Date, format = 'ff', zone = 'local'): string {
+    return this.toZone(value, zone).setLocale(this.locale).toFormat(format);
+  }
+
+  /**
+   * Formats a date using the standard time offset (ignoring daylight saving time) for the specified timezone.
+   *
+   * This method:
+   * 1. Converts the input date to UTC.
+   * 2. Calculates the standard UTC offset for the given timezone (based on January 1st to avoid DST).
+   * 3. Applies the standard offset manually to the UTC time.
+   * 4. Formats the result using the specified format and locale, without applying additional timezone shifts.
+   *
+   * @param value - The ISO string or Date object to format.
+   * @param format - The Luxon format string (default: 'ff').
+   * @param zone - Optional IANA timezone name (e.g., 'America/New_York'); if omitted, system local timezone is used.
+   * @returns A formatted date string adjusted by standard time (non-DST).
+   */
+  formatDateWithStandardOffset(value: string | Date, format = 'ff', zone?: string): string {
+    const utcDate =
+      typeof value === 'string'
+        ? DateTime.fromISO(value, { zone: 'UTC' })
+        : DateTime.fromJSDate(value, { zone: 'UTC' });
+
+    if (!utcDate.isValid) return '';
+
+    const targetZone = zone ?? DateTime.local().zoneName;
+
+    const januaryDate = DateTime.fromObject(
+      { year: utcDate.year, month: 1, day: 1 },
+      { zone: targetZone },
+    );
+    const standardOffset = januaryDate.offset;
+    const dateWithStandardOffset = utcDate.plus({ minutes: standardOffset });
+
+    return dateWithStandardOffset.setZone('UTC').setLocale(this.locale).toFormat(format);
+  }
+
+  /**
+   * Formats the input date using its original clock time, without converting based on timezone or DST
+   *
+   * This method:
+   * 1. Converts the input date to ISO string.
+   * 2. Calculates the date time in UTC, keeping the local time.
+   * 3. Formats the result using the specified format and locale, without shifting timezones.
+   *
+   * @param value - The ISO string or Date object to format.
+   * @param format - The format string (default: 'ff').
+   * @returns A formatted date string without applying timezone.
+   */
+  formatWithoutTimeZone(value: string | Date, format = 'ff'): string {
+    const isoString = value instanceof Date ? value.toISOString() : value;
+
+    const dateTime = DateTime.fromISO(isoString)
+      .setZone('utc', { keepLocalTime: true })
+      .setLocale(this.locale);
+    return dateTime.toFormat(format);
+  }
+}

npm/ng-packs/packages/core/src/lib/services/timezone.service.ts

@@ -21,10 +21,16 @@ export class TimezoneService {
     });
   }
 
-  getBrowserTimezone(): string {
+  /**
-    return Intl.DateTimeFormat().resolvedOptions().timeZone;
+   * Returns the effective timezone to be used across the application.
-  }
+   *
-
+   * This value is determined based on the clock kind setting in the configuration:
+   * - If clock kind is not equal to Utc, the browser's local timezone is returned.
+   * - If clock kind is equal to Utc, the configured timezone (`timeZoneNameFromSettings`) is returned if available;
+   *   otherwise, the browser's timezone is used as a fallback.
+   *
+   * @returns The IANA timezone name (e.g., 'Europe/Istanbul', 'America/New_York').
+   */
   get timezone(): string {
     if (!this.isUtcClockEnabled) {
       return this.getBrowserTimezone();
@@ -32,6 +38,23 @@ export class TimezoneService {
     return this.timeZoneNameFromSettings || this.getBrowserTimezone();
   }
 
+  /**
+   * Retrieves the browser's local timezone based on the user's system settings.
+   *
+   * @returns The IANA timezone name (e.g., 'Europe/Istanbul', 'America/New_York').
+   */
+  getBrowserTimezone(): string {
+    return Intl.DateTimeFormat().resolvedOptions().timeZone;
+  }
+
+  /**
+   * Sets the application's timezone in a cookie to persist the user's selected timezone.
+   *
+   * This method sets the cookie only if the clock kind setting is set to UTC.
+   * The cookie is stored using the key defined by `this.cookieKey` and applied to the root path (`/`).
+   *
+   * @param timezone - The IANA timezone name to be stored (e.g., 'Europe/Istanbul').
+   */
   setTimezone(timezone: string): void {
     if (this.isUtcClockEnabled) {
       this.document.cookie = `${this.cookieKey}=${timezone}; path=/`;