Snap reservation only to available dates on the gridpositions

src/Reservation.qml

@@ -7,6 +7,8 @@ Label {
 
     required property Item dragParent
     required property string holder
+    required property int nights
+    required property int reservationId
     required property string reservationStatus
 
     Drag.active: dragHandler.active

src/ReservationsTimeline.qml

@@ -189,13 +189,48 @@ Control {
         }
 
         DropArea {
+            property int prevDay
+            property int prevLodging
+
+            function addDays(date, days) {
+                var newDate = new Date(date);
+                newDate.setDate(date.getDate() + days);
+                return newDate;
+            }
+
+            function findDayAndLodging(drag: DragEvent): list<int> {
+                const pos = timelineList.contentItem.mapFromItem(this, drag.x, drag.y);
+                const day = Math.floor(pos.x / control.dayWidth);
+                const lodging = Math.floor(pos.y / control.rowHeight);
+                return [day, lodging];
+            }
+
+            function isSpotAvailable(day: int, lodging: int, reservation: Reservation): bool {
+                const view = timelineList.itemAtIndex(lodging);
+                if (!view) {
+                    return false;
+                }
+
+                return view.timeline.areDatesAvailable(addDays(control.fromDate, day), addDays(control.fromDate, day + reservation.nights), reservation.reservationId);
+            }
+
             anchors.fill: timelineList
             anchors.leftMargin: -30 * control.dayWidth
 
+            onEntered: function (drag) {
+                [prevDay, prevLodging] = findDayAndLodging(drag);
+            }
             onPositionChanged: function (drag) {
-                const pos = timelineList.contentItem.mapFromItem(this, drag.x, drag.y);
+                let [day, lodging] = findDayAndLodging(drag);
-                drag.source.y = (Math.floor(pos.y / control.rowHeight)) * control.rowHeight;
+                if ((day != prevDay || lodging != prevLodging) && isSpotAvailable(day, lodging, drag.source)) {
-                drag.source.x = (Math.floor(pos.x / control.dayWidth) + .5) * control.dayWidth;
+                    prevDay = day;
+                    prevLodging = lodging;
+                } else {
+                    day = prevDay;
+                    lodging = prevLodging;
+                }
+                drag.source.y = lodging * control.rowHeight;
+                drag.source.x = (day + .5) * control.dayWidth;
             }
         }
     }

src/timelinemodel.cpp

@@ -16,6 +16,31 @@ void TimelineModel::update(const QList<Item *> &items)
     m_items.assign(items.begin(), items.end());
 }
 
+bool TimelineModel::areDatesAvailable(QDate arrival, QDate departure, int excludedId) const
+{
+    auto [begin, end] = indexesOf(arrival, departure);
+    if (begin == end) {
+        return true;
+    }
+    const Item *first = m_items.at(begin);
+    if (first->id == excludedId) {
+        begin++;
+        if (begin == end) {
+            return true;
+        }
+        first = m_items.at(begin);
+    }
+    const Item *last = m_items.at(end - 1);
+    if (last->id == excludedId) {
+        --end;
+        if (begin == end) {
+            return true;
+        }
+        last = m_items.at(end - 1);
+    }
+    return arrival >= last->departure() || departure <= first->arrival;
+}
+
 std::pair<qsizetype, qsizetype> TimelineModel::indexesOf(QDate from, QDate to) const
 {
     qsizetype begin = searchIndex(from);
@@ -31,6 +56,10 @@ std::pair<qsizetype, qsizetype> TimelineModel::indexesOf(QDate from, QDate to) c
         }
     }
 
+    if (begin == 0 && m_items.at(begin)->arrival >= to) {
+        return std::make_pair(begin, begin);
+    }
+
     for (qsizetype end = begin + 1; end < m_items.count(); end++) {
         if (m_items.at(end)->arrival >= to) {
             return std::make_pair(begin, end);

src/timelinemodel.h

@@ -31,6 +31,7 @@ public:
 
     void update(const QList<Item *> &items);
 
+    Q_INVOKABLE bool areDatesAvailable(QDate arrival, QDate departure, int excludeId) const;
     std::pair<qsizetype, qsizetype> indexesOf(QDate from, QDate to) const;
     const Item *at(qsizetype index) const;
 

src/timelineview.cpp

@@ -174,6 +174,8 @@ TimelineView::Item *TimelineView::createItem(qint64 day, const TimelineModel::It
     if (m_reusableItems.isEmpty()) {
         QVariantMap initialProperties{
             {"holder", modelItem.holder},
+            {"nights", modelItem.nights},
+            {"reservationId", modelItem.id},
             {"reservationStatus", modelItem.status},
         };
         item = qobject_cast<QQuickItem *>(
@@ -186,6 +188,8 @@ TimelineView::Item *TimelineView::createItem(qint64 day, const TimelineModel::It
     } else {
         item = m_reusableItems.takeLast();
         item->setProperty("holder", modelItem.holder);
+        item->setProperty("nights", modelItem.nights);
+        item->setProperty("reservationId", modelItem.id);
         item->setProperty("reservationStatus", modelItem.status);
     }
     auto *viewItem = new TimelineView::Item(day, modelItem.nights, *item, *this);