From 7c7a6df6e45a82d55fda1c7bb4877d9f3d287dc5 Mon Sep 17 00:00:00 2001
From: mfcar <marcosfcar@gmail.com>
Date: Tue, 28 Feb 2023 17:04:46 +0000
Subject: [PATCH] Using cron-parse lib to parse the cron expression. Cron-parse
 can handle with more scenarios.

---
 client/package.json     |  3 +-
 client/plugins/utils.js | 63 ++---------------------------------------
 2 files changed, 5 insertions(+), 61 deletions(-)

diff --git a/client/package.json b/client/package.json
index 26c40356..65f95b28 100644
--- a/client/package.json
+++ b/client/package.json
@@ -16,6 +16,7 @@
     "@nuxtjs/axios": "^5.13.6",
     "@nuxtjs/proxy": "^2.1.0",
     "core-js": "^3.16.0",
+    "cron-parser": "^4.7.1",
     "date-fns": "^2.25.0",
     "epubjs": "^0.3.88",
     "hls.js": "^1.0.7",
@@ -36,4 +37,4 @@
     "postcss": "^8.3.6",
     "tailwindcss": "^3.1.4"
   }
-}
\ No newline at end of file
+}
diff --git a/client/plugins/utils.js b/client/plugins/utils.js
index 57982c0f..c9ece333 100644
--- a/client/plugins/utils.js
+++ b/client/plugins/utils.js
@@ -1,4 +1,5 @@
 import Vue from 'vue'
+import cronParser from 'cron-parser'
 
 Vue.prototype.$bytesPretty = (bytes, decimals = 2) => {
   if (isNaN(bytes) || bytes == 0) {
@@ -137,44 +138,8 @@ Vue.prototype.$parseCronExpression = (expression) => {
 }
 
 Vue.prototype.$getNextScheduledDate = (expression) => {
-  const cronFields = expression.split(' ');
-  const currentDate = new Date();
-  const nextDate = new Date();
-
-  // Calculate next minute
-  const minute = cronFields[0];
-  const currentMinute = currentDate.getMinutes();
-  const nextMinute = getNextValue(minute, currentMinute, 59);
-  nextDate.setMinutes(nextMinute);
-
-  // Calculate next hour
-  const hour = cronFields[1];
-  const currentHour = currentDate.getHours();
-  const nextHour = getNextValue(hour, currentHour, 23);
-  nextDate.setHours(nextHour);
-
-  // Calculate next day of month
-  const dayOfMonth = cronFields[2];
-  const currentDayOfMonth = currentDate.getDate();
-  const lastDayOfMonth = new Date(currentDate.getFullYear(), currentDate.getMonth() + 1, 0).getDate();
-  const nextDayOfMonth = getNextValue(dayOfMonth, currentDayOfMonth, lastDayOfMonth);
-  nextDate.setDate(nextDayOfMonth);
-
-  // Calculate next month
-  const month = cronFields[3];
-  const currentMonth = currentDate.getMonth() + 1;
-  const nextMonth = getNextValue(month, currentMonth, 12);
-  nextDate.setMonth(nextMonth - 1);
-
-  // Calculate next day of week
-  const dayOfWeek = cronFields[4];
-  const currentDayOfWeek = currentDate.getDay();
-  const nextDayOfWeek = getNextValue(dayOfWeek, currentDayOfWeek, 6);
-  const daysUntilNextDayOfWeek = getNextDaysUntilDayOfWeek(currentDate, nextDayOfWeek);
-  nextDate.setDate(currentDate.getDate() + daysUntilNextDayOfWeek);
-
-  // Return the next scheduled date
-  return nextDate;
+  const interval = cronParser.parseExpression(expression);
+  return interval.next().toDate()
 }
 
 export function supplant(str, subs) {
@@ -186,25 +151,3 @@ export function supplant(str, subs) {
     }
   )
 }
-
-function getNextValue(cronField, currentValue, maxValue) {
-  if (cronField === '*') {
-    return currentValue + 1 <= maxValue ? currentValue + 1 : 0;
-  }
-  const values = cronField.split(',');
-  const len = values.length;
-  let nextValue = parseInt(values[0]);
-  for (let i = 0; i < len; i++) {
-    const value = parseInt(values[i]);
-    if (value > currentValue) {
-      nextValue = value;
-      break;
-    }
-  }
-  return nextValue <= maxValue ? nextValue : parseInt(values[0]);
-}
-
-function getNextDaysUntilDayOfWeek(currentDate, nextDayOfWeek) {
-  const daysUntilNextDayOfWeek = (nextDayOfWeek + 7 - currentDate.getDay()) % 7;
-  return daysUntilNextDayOfWeek === 0 ? 7 : daysUntilNextDayOfWeek;
-}