From 4a050e92a8bcc83b1425668240d2977c7d4f473e Mon Sep 17 00:00:00 2001
From: Ulas Kalayci <ulas.kalayci@googlemail.com>
Date: Thu, 30 Apr 2026 10:51:01 +0200
Subject: [PATCH] chore: release v0.38.2
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Fix recurring events with FREQ=WEEKLY;INTERVAL=N;BYDAY ignoring the
interval when crossing a week boundary (e.g. Friday → Monday).

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
---
 CHANGELOG.md                  |  5 +++++
 package-lock.json             |  4 ++--
 package.json                  |  2 +-
 server/services/recurrence.js |  8 +++++++-
 test-calendar.js              | 27 +++++++++++++++++++++++++++
 5 files changed, 42 insertions(+), 4 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index ad690af..92aa057 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,11 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+## [0.38.2] - 2026-04-30
+
+### Fixed
+- Recurring calendar events with `FREQ=WEEKLY;INTERVAL=N;BYDAY=...` (N > 1) now correctly skip N−1 weeks between occurrences instead of repeating every week
+
 ## [0.38.1] - 2026-04-30
 
 ### Changed
diff --git a/package-lock.json b/package-lock.json
index 3ca5b3f..40c5af5 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "oikos",
-  "version": "0.38.1",
+  "version": "0.38.2",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "oikos",
-      "version": "0.38.1",
+      "version": "0.38.2",
       "license": "MIT",
       "dependencies": {
         "bcrypt": "^6.0.0",
diff --git a/package.json b/package.json
index 41d5176..d3fa6d2 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "oikos",
-  "version": "0.38.1",
+  "version": "0.38.2",
   "description": "Self-hosted family planner - calendar, tasks, shopping, meal planning, budget and more. Private, open-source, no subscription.",
   "main": "server/index.js",
   "type": "module",
diff --git a/server/services/recurrence.js b/server/services/recurrence.js
index db3f5c4..30a7129 100644
--- a/server/services/recurrence.js
+++ b/server/services/recurrence.js
@@ -78,7 +78,13 @@ function nextOccurrence(baseDateStr, rrule) {
       });
       // Tage bis zum nächsten Vorkommen (mind. 1, damit nicht derselbe Tag)
       let daysUntil = (sorted[0] - currentDay + 7) % 7;
-      if (daysUntil === 0) daysUntil = 7 * interval;
+      if (daysUntil === 0) {
+        // Selber Wochentag → ganzes Intervall überspringen
+        daysUntil = 7 * interval;
+      } else if ((sorted[0] + 6) % 7 < (currentDay + 6) % 7) {
+        // Wochengrenze überschritten (ISO-Woche MO–SO) → interval-1 Wochen extra überspringen
+        daysUntil += 7 * (interval - 1);
+      }
       next.setUTCDate(next.getUTCDate() + daysUntil);
     }
 
diff --git a/test-calendar.js b/test-calendar.js
index 79bd72f..a4e6ded 100644
--- a/test-calendar.js
+++ b/test-calendar.js
@@ -251,6 +251,33 @@ test('Monatsbereich: 42 Tage für Kalenderraster', () => {
   assert(to === '2026-04-11', `Erwartet 2026-04-11, erhalten ${to}`);
 });
 
+// --------------------------------------------------------
+// nextOccurrence: INTERVAL-Korrektheit mit BYDAY
+// --------------------------------------------------------
+import { nextOccurrence } from './server/services/recurrence.js';
+
+test('nextOccurrence: WEEKLY BYDAY=MO,TU,WE,TH,FR INTERVAL=2 — kein täglicher Übergang', () => {
+  const rule = 'FREQ=WEEKLY;BYDAY=MO,TU,WE,TH,FR;INTERVAL=2';
+  // Innerhalb der Woche: Mo→Di (1 Tag, kein Intervallsprung)
+  assert(nextOccurrence('2026-05-04', rule) === '2026-05-05', 'Mo→Di');
+  // Innerhalb der Woche: Di→Mi
+  assert(nextOccurrence('2026-05-05', rule) === '2026-05-06', 'Di→Mi');
+  // Freitag → Montag der übernächsten Woche (3 + 7 = 10 Tage)
+  assert(nextOccurrence('2026-05-08', rule) === '2026-05-18', 'Fr→Mo (übernächste Woche)');
+});
+
+test('nextOccurrence: WEEKLY BYDAY=SA,SU INTERVAL=2 — Wochenend-Pair bleibt zusammen', () => {
+  const rule = 'FREQ=WEEKLY;BYDAY=SA,SU;INTERVAL=2';
+  // Sa→So (1 Tag, gleiche Woche)
+  assert(nextOccurrence('2026-05-09', rule) === '2026-05-10', 'Sa→So');
+  // So→Sa der übernächsten Woche (13 Tage)
+  assert(nextOccurrence('2026-05-10', rule) === '2026-05-23', 'So→Sa (übernächste Woche)');
+});
+
+test('nextOccurrence: WEEKLY BYDAY=MO INTERVAL=2 — klassisch alle 2 Wochen', () => {
+  assert(nextOccurrence('2026-05-04', 'FREQ=WEEKLY;BYDAY=MO;INTERVAL=2') === '2026-05-18', 'Mo→Mo+14');
+});
+
 // --------------------------------------------------------
 // Ergebnis
 // --------------------------------------------------------