Properly handle parent task deletion, preventing crashing on modifying orphaned child task

src/calendarmanager.cpp

@@ -660,8 +660,54 @@ void CalendarManager::editIncidence(IncidenceWrapper *incidenceWrapper)
     });
 }
 
-void CalendarManager::deleteIncidence(KCalendarCore::Incidence::Ptr incidence)
+bool CalendarManager::hasChildren(KCalendarCore::Incidence::Ptr incidence)
 {
+    return !m_calendar->childIncidences(incidence->uid()).isEmpty();
+}
+
+void CalendarManager::deleteAllChildren(KCalendarCore::Incidence::Ptr incidence)
+{
+    auto allChildren = m_calendar->childIncidences(incidence->uid());
+
+    for (auto child : allChildren) {
+        if (!m_calendar->childIncidences(child->uid()).isEmpty()) {
+            deleteAllChildren(child);
+        }
+    }
+
+    for (auto child : allChildren) {
+        m_calendar->deleteIncidence(child);
+    }
+}
+
+void CalendarManager::deleteIncidence(KCalendarCore::Incidence::Ptr incidence, bool deleteChildren)
+{
+    auto directChildren = m_calendar->childIncidences(incidence->uid());
+
+    if (!directChildren.isEmpty()) {
+        if (deleteChildren) {
+            m_changer->startAtomicOperation(i18n("Delete task and its sub-tasks"));
+            deleteAllChildren(incidence);
+        } else {
+            m_changer->startAtomicOperation(i18n("Delete task and make sub-tasks independent"));
+            for (auto child : directChildren) {
+                for (auto instance : m_calendar->instances(child)) {
+                    KCalendarCore::Incidence::Ptr oldInstance(instance->clone());
+                    instance->setRelatedTo(QString());
+                    m_changer->modifyIncidence(m_calendar->item(instance), oldInstance);
+                }
+
+                KCalendarCore::Incidence::Ptr oldInc(child->clone());
+                child->setRelatedTo(QString());
+                m_changer->modifyIncidence(m_calendar->item(child), oldInc);
+            }
+        }
+
+        m_calendar->deleteIncidence(incidence);
+        m_changer->endAtomicOperation();
+        return;
+    }
+
     m_calendar->deleteIncidence(incidence);
 }
 

src/calendarmanager.h

@@ -72,7 +72,9 @@ public:
 
     Q_INVOKABLE void addIncidence(IncidenceWrapper *incidenceWrapper);
     Q_INVOKABLE void editIncidence(IncidenceWrapper *incidenceWrapper);
-    Q_INVOKABLE void deleteIncidence(KCalendarCore::Incidence::Ptr incidence);
+    Q_INVOKABLE bool hasChildren(KCalendarCore::Incidence::Ptr incidence);
+    void deleteAllChildren(KCalendarCore::Incidence::Ptr incidence);
+    Q_INVOKABLE void deleteIncidence(KCalendarCore::Incidence::Ptr incidence, bool deleteChildren = false);
     Q_INVOKABLE QVariantMap getCollectionDetails(QVariant collectionId);
     Q_INVOKABLE void setCollectionColor(qint64 collectionId, QColor color);
     Q_INVOKABLE QVariant getIncidenceSubclassed(KCalendarCore::Incidence::Ptr incidencePtr);

src/contents/ui/DeleteIncidenceSheet.qml

@@ -13,8 +13,10 @@ Kirigami.OverlaySheet {
     signal addException(date exceptionDate, var incidenceWrapper)
     signal addRecurrenceEndDate(date endDate, var incidenceWrapper)
     signal deleteIncidence(var incidencePtr)
+    signal deleteIncidenceWithChildren(var incidencePtr)
 
     property var incidenceWrapper
+    property bool incidenceHasChildren: incidenceWrapper !== undefined ? CalendarManager.hasChildren(incidenceWrapper.incidencePtr) : false
     property date deleteDate
 
     header: Kirigami.Heading {
@@ -24,7 +26,12 @@ Kirigami.OverlaySheet {
 
     footer: Loader {
         active: incidenceWrapper !== undefined
-        sourceComponent: QQC2.DialogButtonBox {
+        sourceComponent: RowLayout {
+            spacing: Kirigami.Units.smallSpacing
+
+            Item {
+                Layout.fillWidth: true
+            }
 
             QQC2.Button {
                 icon.name: "deletecell"
@@ -50,20 +57,26 @@ Kirigami.OverlaySheet {
             }
 
             QQC2.Button {
-                icon.name: "delete"
-                text: incidenceWrapper.recurrenceData.type > 0 ? i18n("Delete All") : i18n("Delete")
+                icon.name: "group-delete"
+                text: i18n("Delete Only This")
+                visible: deleteIncidenceSheet.incidenceHasChildren && incidenceWrapper.recurrenceData.type === 0
                 onClicked: deleteIncidence(incidenceWrapper.incidencePtr)
                 QQC2.DialogButtonBox.buttonRole: QQC2.DialogButtonBox.AcceptRole
             }
 
+            QQC2.Button {
+                icon.name: "delete"
+                text: deleteIncidenceSheet.incidenceHasChildren || incidenceWrapper.recurrenceData.type > 0 ? i18n("Delete All") : i18n("Delete")
+                onClicked: deleteIncidenceSheet.incidenceHasChildren ? deleteIncidenceWithChildren(incidenceWrapper.incidencePtr) : deleteIncidence(incidenceWrapper.incidencePtr)
+                QQC2.DialogButtonBox.buttonRole: QQC2.DialogButtonBox.AcceptRole
+            }
+
             QQC2.Button {
                 icon.name: "dialog-cancel"
                 text: i18n("Cancel")
                 onClicked: deleteIncidenceSheet.close()
                 QQC2.DialogButtonBox.buttonRole: QQC2.DialogButtonBox.DestructiveRole
             }
-
-            onRejected: deleteIncidenceSheet.close()
         }
     }
 
@@ -83,15 +96,15 @@ Kirigami.OverlaySheet {
 
             QQC2.Label {
                 Layout.fillWidth: true
-                text: i18n("Do you really want to delete item: \"%1\"?", incidenceWrapper.summary)
-                visible: incidenceWrapper.recurrenceData.type === 0
-                wrapMode: Text.WordWrap
-            }
-
-            QQC2.Label {
-                Layout.fillWidth: true
-                text: i18n("The calendar item \"%1\" recurs over multiple dates. Do you want to delete the selected occurrence on %2, also future occurrences, or all of its occurrences?", incidenceWrapper.summary, deleteDate.toLocaleDateString(Qt.locale()))
-                visible: incidenceWrapper.recurrenceData.type > 0
+                text: if(incidenceWrapper.recurrenceData.type === 0 && !deleteIncidenceSheet.incidenceHasChildren) {
+                    return i18n("Do you want to delete item: \"%1\"?", incidenceWrapper.summary)
+                } else if(incidenceWrapper.recurrenceData.type === 0 && deleteIncidenceSheet.incidenceHasChildren) {
+                    return i18n("Item \"%1\" has sub-items. Do you want to delete all related items, or just the currently selected item?", incidenceWrapper.summary)
+                } else if (incidenceWrapper.recurrenceData.type > 0 && deleteIncidenceSheet.incidenceHasChildren) {
+                    return i18n("The calendar item \"%1\" recurs over multiple dates. This item also has sub-items.\n\nDo you want to delete the selected occurrence on %2, also future occurrences, or all of its occurrences?\n\nDeleting all will also delete sub-items!", incidenceWrapper.summary, deleteDate.toLocaleDateString(Qt.locale()))
+                } else if (incidenceWrapper.recurrenceData.type > 0) {
+                    return i18n("The calendar item \"%1\" recurs over multiple dates. Do you want to delete the selected occurrence on %2, also future occurrences, or all of its occurrences?", incidenceWrapper.summary, deleteDate.toLocaleDateString(Qt.locale()))
+                }
                 wrapMode: Text.WordWrap
             }
         }

src/contents/ui/main.qml

@@ -661,6 +661,10 @@ Kirigami.ApplicationWindow {
             CalendarManager.deleteIncidence(incidencePtr);
             deleteIncidenceSheet.close();
         }
+        onDeleteIncidenceWithChildren: {
+            CalendarManager.deleteIncidence(incidencePtr, true);
+            deleteIncidenceSheet.close();
+        }
     }
 
     Component {