feat(calendar): pass slotsPerDay to generator, show skipped-dates warning

js/calendar.js

@@ -80,6 +80,11 @@ export function renderCalendar() {
     '<span><span class="cal-legend-dot" style="background:#fecaca"></span>Betriebsurlaub</span>';
   container.appendChild(legend);
 
+  const warnBox = document.createElement('div');
+  warnBox.id = 'skipped-warning';
+  warnBox.style.display = 'none';
+  container.appendChild(warnBox);
+
   // Calendar grid wrapper
   const wrapper = document.createElement('div');
   wrapper.className = 'calendar-outer';
@@ -114,12 +119,15 @@ export function renderCalendar() {
     }
     const workdays = getWorkdays(currentYear, currentMonth,
       state.calendar.holidays, state.calendar.companyClosures);
-    const prefix = currentYear + '-' + String(currentMonth).padStart(2,'0');
+    const prefix = currentYear + '-' + String(currentMonth).padStart(2, '0');
     const historyWithoutMonth = state.history.filter(h => !h.date.startsWith(prefix));
-    const result = generatePlan(workdays, state.employees, historyWithoutMonth);
+    // Reset month entries from history so dedup-by-(date,employeeId) doesn't keep stale rows
+    state.history = historyWithoutMonth;
+    const result = generatePlan(workdays, state.employees, historyWithoutMonth, Math.random, state.settings.moderatorsPerDay);
     currentPlan = result.assignments;
     addHistoryEntries(state, currentPlan);
     saveState();
+    renderSkippedWarning(warnBox, result.skippedDates);
     renderGrid(wrapper, exportBtn);
   });
 
@@ -291,3 +299,33 @@ function renderGrid(wrapper, exportBtn) {
   wrapper.appendChild(bodyGrid);
   exportBtn.style.display = currentPlan.length > 0 ? 'inline-block' : 'none';
 }
+
+function renderSkippedWarning(box, skippedDates) {
+  box.replaceChildren();
+  if (!skippedDates || skippedDates.length === 0) {
+    box.style.display = 'none';
+    return;
+  }
+  box.style.display = 'flex';
+  box.className = 'skipped-warning';
+
+  const formatted = skippedDates.map(d => {
+    const [y, m, day] = d.split('-');
+    return day + '.' + m + '.';
+  }).join(', ');
+
+  const text = document.createElement('span');
+  text.textContent = skippedDates.length === 1
+    ? '1 Tag konnte nicht vollständig besetzt werden: ' + formatted
+    : skippedDates.length + ' Tage konnten nicht vollständig besetzt werden: ' + formatted;
+  box.appendChild(text);
+
+  const closeBtn = document.createElement('button');
+  closeBtn.type = 'button';
+  closeBtn.textContent = '✕';
+  closeBtn.addEventListener('click', () => {
+    box.replaceChildren();
+    box.style.display = 'none';
+  });
+  box.appendChild(closeBtn);
+}