feat(service): add date command for Gregorian and Persian date handling

- Introduce `tehranZone` function:
  - Adjusts the current date and time to Tehran timezone (UTC+3:30) without considering daylight saving time.

- Add `DateCommand` class:
  - Provides functionality to retrieve the current date in both Gregorian and Persian calendars.

- `date` method:
  - Returns the formatted Gregorian and Persian dates by combining timezone adjustments and conversion logic.
  - Utilizes the `@Catch` decorator to handle potential runtime errors.

- `formatGregorianDate` method:
  - Formats a `Date` object into a human-readable string (e.g., "Sunday, January 1, 2024, time: 12:00").
  - Includes day names, month names, and padded hours and minutes.

- `convertToPersianDate` method:
  - Converts a `Date` object into a Persian calendar format with day names and month names in Farsi.
  - Outputs in the format: `<day> <day_of_month> <month_name> <year> ساعت: <hours>:<minutes>`.

- `toJalaali` method:
  - Implements a Gregorian-to-Jalaali (Persian calendar) conversion algorithm.
  - Calculates Persian year, month, and day based on the input Gregorian date.
  - Accounts for leap years and Persian calendar-specific calculations.

Author: m-mdy-m

src/bot/service/general/date.ts

@@ -0,0 +1,84 @@
+import { Context } from 'grammy';
+import { Catch } from '../../../decorators/Catch';
+export function tehranZone() {
+  // Get current date and adjust to Tehran time zone
+  const now = new Date();
+  const utcTime = now.getTime() + now.getTimezoneOffset() * 60000;
+
+  // Tehran timezone offset in minutes (UTC+3:30)
+  const tehranOffset = 3.5 * 60;
+
+  // Adjust time to Tehran timezone without considering DST
+  return new Date(utcTime + tehranOffset * 60000);
+}
+export class DateCommand {
+  @Catch()
+  static async date(): Promise<{
+    gregorianDate: string;
+    persianDate: string;
+  }> {
+    const tehranTime = tehranZone();
+    // Format Gregorian Date
+    const gregorianDate = this.formatGregorianDate(tehranTime);
+    // Convert to Persian Date
+    const persianDate = this.convertToPersianDate(tehranTime);
+    return {
+      gregorianDate,
+      persianDate,
+    };
+  }
+  static formatGregorianDate(date: Date): string {
+    const days = ['Sunday', 'Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday', 'Saturday'];
+    const months = ['January', 'February', 'March', 'April', 'May', 'June', 'July', 'August', 'September', 'October', 'November', 'December'];
+
+    const dayName = days[date.getDay()];
+    const day = date.getDate();
+    const monthName = months[date.getMonth()];
+    const year = date.getFullYear();
+    const hours = date.getHours().toString().padStart(2, '0');
+    const minutes = date.getMinutes().toString().padStart(2, '0');
+
+    return `${dayName}, ${monthName} ${day}, ${year}, time: ${hours}:${minutes}`;
+  }
+
+  static convertToPersianDate(date: Date): string {
+    // Gy: Gregorian year
+    // Gm: Gregorian month (1-12)
+    // Gd: Gregorian day of the month (1-31)
+    const persianDate = this.toJalaali(date.getFullYear(), date.getMonth() + 1, date.getDate());
+    const persianDays = ['شنبه', 'یکشنبه', 'دوشنبه', 'سه‌شنبه', 'چهارشنبه', 'پنج‌شنبه', 'جمعه'];
+
+    const persianMonths = ['فروردین', 'اردیبهشت', 'خرداد', 'تیر', 'مرداد', 'شهریور', 'مهر', 'آبان', 'آذر', 'دی', 'بهمن', 'اسفند'];
+    const dayName = Number(date.getDay() + 1) >= 7 ? persianDays[date.getDay() - 6] : persianDays[date.getDay() + 1];
+    const hours = date.getHours().toString().padStart(2, '0');
+    const minutes = date.getMinutes().toString().padStart(2, '0');
+
+    return `${dayName} ${persianDate.jd} ${persianMonths[persianDate.jm - 1]} ${persianDate.jy} ساعت: ${hours}:${minutes}`;
+  }
+
+  static toJalaali(gy: number, gm: number, gd: number) {
+    const g_d_m = [0, 31, (gy % 4 === 0 && gy % 100 !== 0) || gy % 400 === 0 ? 29 : 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31];
+    let gy2 = gm > 2 ? gy + 1 : gy;
+    let days = 355666 + 365 * gy + Math.floor((gy2 + 3) / 4) - Math.floor((gy2 + 99) / 100) + Math.floor((gy2 + 399) / 400) + gd;
+
+    for (let i = 0; i < gm; ++i) days += g_d_m[i];
+
+    let jy = -1595 + 33 * Math.floor(days / 12053);
+    days %= 12053;
+
+    jy += 4 * Math.floor(days / 1461);
+    days %= 1461;
+
+    if (days > 365) {
+      jy += Math.floor((days - 1) / 365);
+      days = (days - 1) % 365;
+    }
+
+    // Month Calculation
+    const jm = days < 186 ? 1 + Math.floor(days / 31) : 7 + Math.floor((days - 186) / 30);
+
+    // Day Calculation
+    const jd = days < 186 ? days % 31 : (days - 186) % 30;
+    return { jy, jm, jd };
+  }
+}