Change leap year calculation

The new calculation is based on @roozbehp's code
https://github.com/roozbehp/persiancalendar/blob/main/persiancalendar_fast.py

src/constants.js

@@ -3,5 +3,22 @@ module.exports = {
   ABBR_DAYS: ['۱ش', '۲ش', '۳ش', '۴ش', '۵ش', 'ج', 'ش'],
   DAYS_NAMES: ['یکشنبه', 'دوشنبه', 'سه‌شنبه', 'چهارشنبه', 'پنج‌شنبه', 'جمعه', 'شنبه'],
   GREGORIAN_EPOCH: 1721425.5,
-  PERSIAN_EPOCH: 1948320.5
+  PERSIAN_EPOCH: 1948320.5,
+  NON_LEAP_CORRECTION: [
+    1502,
+    1601, 1634, 1667,
+    1700, 1733, 1766, 1799,
+    1832, 1865, 1898,
+    1931, 1964, 1997,
+    2030, 2059, 2063, 2096,
+    2129, 2158, 2162, 2191, 2195,
+    2224, 2228, 2257, 2261, 2290, 2294,
+    2323, 2327, 2356, 2360, 2389, 2393,
+    2422, 2426, 2455, 2459, 2488, 2492,
+    2521, 2525, 2554, 2558, 2587, 2591,
+    2620, 2624, 2653, 2657, 2686, 2690,
+    2719, 2723, 2748, 2752, 2756, 2781, 2785, 2789,
+    2818, 2822, 2847, 2851, 2855, 2880, 2884, 2888,
+    2913, 2917, 2921, 2946, 2950, 2954, 2979, 2983, 2987
+  ]
 };

src/converter.js

@@ -1,5 +1,5 @@
 import { mod } from './helpers';
-import { GREGORIAN_EPOCH, PERSIAN_EPOCH } from './constants';
+import { GREGORIAN_EPOCH, PERSIAN_EPOCH, NON_LEAP_CORRECTION } from './constants';
 
 export default class Converter {
   //  LEAP_GREGORIAN  --  Is a given year in the Gregorian calendar a leap year?
@@ -57,10 +57,13 @@ export default class Converter {
 
   //  LEAP_PERSIAN  --  Is a given year a leap year in the Persian calendar ?
   static leapPersian(year) {
-    if (year === 1403) return true; // Well, algorithms are not perfect \o/
-    return (
-      (((((year - ((year > 0) ? 474 : 473)) % 2820) + 474) + 38) * 682) % 2816
-    ) < 682;
+    if (NON_LEAP_CORRECTION.includes(year)) {
+      return false;
+    } if (NON_LEAP_CORRECTION.includes(year - 1)) {
+      return true;
+    }
+
+    return (25 * year + 11) % 33 < 8;
   }
 
   //  PERSIAN_TO_JD  --  Determine Julian day from Persian date