src/components/EventOverlay.vue

@@ -161,6 +161,25 @@ function startLocalDrag(init, evt) {
   window.addEventListener('pointercancel', onDragPointerUp, { passive: false })
 }
 
+// Determine date under pointer: traverse DOM to find day cell carrying data-date attribute
+function getDateUnderPointer(x, y, el) {
+  let cur = el
+  while (cur) {
+    if (cur.dataset && cur.dataset.date) {
+      return { date: cur.dataset.date }
+    }
+    cur = cur.parentElement
+  }
+  // Fallback: elementFromPoint scan
+  const probe = document.elementFromPoint(x, y)
+  let p = probe
+  while (p) {
+    if (p.dataset && p.dataset.date) return { date: p.dataset.date }
+    p = p.parentElement
+  }
+  return null
+}
+
 function onDragPointerMove(e) {
   const st = dragState.value
   if (!st) return
@@ -234,9 +253,12 @@ function normalizeDateOrder(aStr, bStr) {
 }
 
 function applyRangeDuringDrag(st, startDate, endDate) {
-  // If dragging a virtual occurrence, map to base move without changing recurrence pattern mid-series.
-  // We disallow resizing individual virtual occurrences; treat as move of whole series anchor.
-  if (st.isVirtual && st.mode !== 'move') return
+  if (st.isVirtual) {
+    if (st.mode !== 'move') return // no resize for virtual occurrence
+    // Split-move: occurrence being dragged treated as first of new series
+    store.splitMoveVirtualOccurrence(st.id, st.startDate, startDate, endDate)
+    return
+  }
   store.setEventRange(st.id, startDate, endDate, { mode: st.mode })
 }
 

src/stores/CalendarStore.js

@@ -586,6 +586,98 @@ export const useCalendarStore = defineStore('calendar', {
       // no expansion
     },
 
+    // Split a repeating series at a specific occurrence date and move that occurrence (and future) to new range
+    splitMoveVirtualOccurrence(baseId, occurrenceDateStr, newStartStr, newEndStr) {
+      const base = this._findEventInAnyList(baseId)
+      if (!base || !base.isRepeating) return
+      const originalCountRaw = base.repeatCount
+      const spanDays = Math.max(
+        0,
+        Math.round(
+          (fromLocalString(base.endDate) - fromLocalString(base.startDate)) / (24 * 60 * 60 * 1000),
+        ),
+      )
+      const occurrenceDate = fromLocalString(occurrenceDateStr)
+      const baseStart = fromLocalString(base.startDate)
+      if (occurrenceDate <= baseStart) {
+        // Moving the base itself: just move entire series
+        this.setEventRange(baseId, newStartStr, newEndStr, { mode: 'move' })
+        return
+      }
+      let keptOccurrences = 0 // number of occurrences BEFORE the moved one
+      if (base.repeat === 'weeks') {
+        const interval = base.repeatInterval || 1
+        const pattern = base.repeatWeekdays || []
+        if (!pattern.some(Boolean)) return
+        const WEEK_MS = 7 * 86400000
+        const blockStartBase = new Date(baseStart)
+        blockStartBase.setDate(blockStartBase.getDate() - blockStartBase.getDay())
+        function isAligned(d) {
+          const blk = new Date(d)
+          blk.setDate(d.getDate() - d.getDay())
+          const diff = Math.floor((blk - blockStartBase) / WEEK_MS)
+            return diff % interval === 0
+        }
+        const cursor = new Date(baseStart)
+        while (cursor < occurrenceDate) {
+          if (pattern[cursor.getDay()] && isAligned(cursor)) keptOccurrences++
+          cursor.setDate(cursor.getDate() + 1)
+        }
+      } else if (base.repeat === 'months') {
+        const diffMonths =
+          (occurrenceDate.getFullYear() - baseStart.getFullYear()) * 12 +
+          (occurrenceDate.getMonth() - baseStart.getMonth())
+        const interval = base.repeatInterval || 1
+        if (diffMonths <= 0 || diffMonths % interval !== 0) return // invalid occurrence
+        keptOccurrences = diffMonths // base is occurrence 0; we keep all before diffMonths
+      } else {
+        // Unsupported repeat type
+        return
+      }
+      // Truncate original series to keptOccurrences
+      this._terminateRepeatSeriesAtIndex(baseId, keptOccurrences)
+      // Compute remaining occurrences count
+      let remainingCount = 'unlimited'
+      if (originalCountRaw !== 'unlimited') {
+        const total = parseInt(originalCountRaw, 10)
+        if (!isNaN(total)) {
+          const rem = total - keptOccurrences
+          if (rem <= 0) return
+          remainingCount = String(rem)
+        }
+      }
+      // Determine repeat-specific adjustments
+      let repeatWeekdays = base.repeatWeekdays
+      if (base.repeat === 'weeks' && Array.isArray(base.repeatWeekdays)) {
+        // Rotate pattern so that the moved occurrence weekday stays active relative to new anchor
+        const origWeekday = occurrenceDate.getDay()
+        const newWeekday = fromLocalString(newStartStr).getDay()
+        const shift = newWeekday - origWeekday
+        if (shift !== 0) {
+          const rotated = [false, false, false, false, false, false, false]
+          for (let i = 0; i < 7; i++) {
+            if (base.repeatWeekdays[i]) {
+              let ni = (i + shift) % 7
+              if (ni < 0) ni += 7
+              rotated[ni] = true
+            }
+          }
+          repeatWeekdays = rotated
+        }
+      }
+      // Create continuation series starting at newStartStr
+      this.createEvent({
+        title: base.title,
+        startDate: newStartStr,
+        endDate: newEndStr,
+        colorId: base.colorId,
+        repeat: base.repeat,
+        repeatInterval: base.repeatInterval,
+        repeatCount: remainingCount,
+        repeatWeekdays,
+      })
+    },
+
     // Split a repeating series at a given occurrence index; returns new series id
     splitRepeatSeries(baseId, occurrenceIndex, newStartStr, newEndStr, _grabbedWeekday) {
       const base = this._findEventInAnyList(baseId)