Fix calendar rec events (#9755)

Signed-off-by: Denis Bykhov <bykhov.denis@gmail.com>

plugins/calendar/src/__tests__/utils.test.ts

@@ -161,4 +161,40 @@ describe('generateRecurringValues', () => {
     }
     expect(() => generateRecurringValues(rule as any, baseDate, from, to)).toThrow('Invalid recurring rule frequency')
   })
+
+  it('generates simple monthly recurring values (no specific rules)', () => {
+    const rule: RecurringRule = {
+      freq: 'MONTHLY',
+      interval: 1
+    }
+    const startDate = new Date('2024-01-15T10:00:00Z').getTime() // 15th of month
+    const from = new Date('2024-01-01T00:00:00Z').getTime()
+    const to = new Date('2024-04-30T23:59:59Z').getTime()
+    const result = generateRecurringValues(rule, startDate, from, to)
+
+    // Should generate events on 15th of each month: Jan, Feb, Mar, Apr
+    expect(result.length).toBe(4)
+    expect(new Date(result[0]).toISOString().slice(0, 10)).toBe('2024-01-15')
+    expect(new Date(result[1]).toISOString().slice(0, 10)).toBe('2024-02-15')
+    expect(new Date(result[2]).toISOString().slice(0, 10)).toBe('2024-03-15')
+    expect(new Date(result[3]).toISOString().slice(0, 10)).toBe('2024-04-15')
+  })
+
+  it('generates simple yearly recurring values (no specific rules)', () => {
+    const rule: RecurringRule = {
+      freq: 'YEARLY',
+      interval: 1
+    }
+    const startDate = new Date('2024-03-10T10:00:00Z').getTime() // March 10th
+    const from = new Date('2024-01-01T00:00:00Z').getTime()
+    const to = new Date('2027-12-31T23:59:59Z').getTime()
+    const result = generateRecurringValues(rule, startDate, from, to)
+
+    // Should generate events on March 10th of each year: 2024, 2025, 2026, 2027
+    expect(result.length).toBe(4)
+    expect(new Date(result[0]).toISOString().slice(0, 10)).toBe('2024-03-10')
+    expect(new Date(result[1]).toISOString().slice(0, 10)).toBe('2025-03-10')
+    expect(new Date(result[2]).toISOString().slice(0, 10)).toBe('2026-03-10')
+    expect(new Date(result[3]).toISOString().slice(0, 10)).toBe('2027-03-10')
+  })
 })

plugins/calendar/src/utils.ts

@@ -154,11 +154,37 @@ function generateMonthlyValues (rule: RecurringRule, currentDate: Date, from: Ti
     const end = new Date(new Date(currentDate).setMonth(currentDate.getMonth() + 1, 1))
     let date = currentDate
     const candidates: Date[] = []
-    while (date < end) {
-      if ((byDay == null || matchesByDay(date, byDay)) && (byMonthDay == null || byMonthDay.includes(date.getDate()))) {
-        candidates.push(new Date(date))
+
+    // If no specific rules are set except byMonthDay (simple monthly recurrence)
+    if (byDay == null && bySetPos == null && byMonthDay != null) {
+      for (const day of byMonthDay) {
+        const originalDate = new Date(currentDate.getTime())
+        const sameDate = new Date(
+          Date.UTC(
+            currentDate.getUTCFullYear(),
+            currentDate.getUTCMonth(),
+            day,
+            originalDate.getUTCHours(),
+            originalDate.getUTCMinutes(),
+            originalDate.getUTCSeconds(),
+            originalDate.getUTCMilliseconds()
+          )
+        )
+        if (sameDate.getUTCMonth() === currentDate.getUTCMonth()) {
+          // Valid day for this month
+          candidates.push(sameDate)
+        }
+      }
+    } else {
+      while (date < end) {
+        if (
+          (byDay == null || matchesByDay(date, byDay)) &&
+          (byMonthDay == null || byMonthDay.includes(date.getDate()))
+        ) {
+          candidates.push(new Date(date))
+        }
+        date = new Date(date.setDate(date.getDate() + 1))
       }
-      date = new Date(date.setDate(date.getDate() + 1))
     }
 
     let filtered: Date[] = candidates
@@ -197,21 +223,46 @@ function generateYearlyValues (rule: RecurringRule, currentDate: Date, from: Tim
     const end = new Date(new Date(currentDate).setFullYear(currentDate.getFullYear() + 1, 0, 1))
     let date = currentDate
     const candidates: Date[] = []
-    while (date < end) {
-      if (
-        (byDay == null || matchesByDay(date, byDay)) &&
-        (byMonthDay == null || byMonthDay.includes(date.getDate())) &&
-        (byYearDay == null || byYearDay.includes(getYearDay(date))) &&
-        (byWeekNo == null || byWeekNo.includes(getWeekNumber(date))) &&
-        (byMonth == null || byMonth.includes(date.getMonth()))
-      ) {
-        const res = date.getTime()
-        if (res >= from && res <= to) {
-          candidates.push(new Date(res))
+
+    // If no specific rules are set, only generate an event for the same month/day each year
+    if (
+      byDay == null &&
+      byMonthDay == null &&
+      byYearDay == null &&
+      byWeekNo == null &&
+      byMonth == null &&
+      bySetPos == null
+    ) {
+      const originalDate = new Date(currentDate.getTime())
+      const sameDate = new Date(
+        Date.UTC(
+          currentDate.getUTCFullYear(),
+          originalDate.getUTCMonth(),
+          originalDate.getUTCDate(),
+          originalDate.getUTCHours(),
+          originalDate.getUTCMinutes(),
+          originalDate.getUTCSeconds(),
+          originalDate.getUTCMilliseconds()
+        )
+      )
+      candidates.push(sameDate)
+    } else {
+      while (date < end) {
+        if (
+          (byDay == null || matchesByDay(date, byDay)) &&
+          (byMonthDay == null || byMonthDay.includes(date.getDate())) &&
+          (byYearDay == null || byYearDay.includes(getYearDay(date))) &&
+          (byWeekNo == null || byWeekNo.includes(getWeekNumber(date))) &&
+          (byMonth == null || byMonth.includes(date.getMonth()))
+        ) {
+          const res = date.getTime()
+          if (res >= from && res <= to) {
+            candidates.push(new Date(res))
+          }
+          i++
         }
-        i++
+        date = new Date(date.setDate(date.getDate() + 1))
       }
-      date = new Date(date.setDate(date.getDate() + 1))
     }
 
     let filtered: Date[] = candidates
@@ -235,7 +286,7 @@ function generateYearlyValues (rule: RecurringRule, currentDate: Date, from: Tim
     }
     if (endDate != null && next > endDate) return values
     if (next >= to) return values
-    currentDate = new Date(next)
+    currentDate = new Date(currentDate.setFullYear(currentDate.getFullYear() + (interval ?? 1)))
   }
 }