Re-order spaces by dragging and dropping

Title

src/models/spacechildrenmodel.cpp

@@ -8,6 +8,7 @@
 #include <Quotient/room.h>
 
 #include "neochatconnection.h"
+#include "neochatroom.h"
 
 SpaceChildrenModel::SpaceChildrenModel(QObject *parent)
     : QAbstractItemModel(parent)
@@ -32,7 +33,8 @@ void SpaceChildrenModel::setSpace(NeoChatRoom *space)
     }
     // disconnect the new room signal from the old connection in case it is different.
     if (m_space != nullptr) {
-        disconnect(m_space->connection(), &Quotient::Connection::loadedRoomState, this, nullptr);
+        m_space->connection()->disconnect(this);
+        m_space->disconnect(this);
     }
 
     m_space = space;
@@ -116,6 +118,11 @@ void SpaceChildrenModel::insertChildren(std::vector<Quotient::GetSpaceHierarchyJ
                 if (!successorId.isEmpty()) {
                     m_replacedRooms += successorId;
                 }
+                if (dynamic_cast<NeoChatRoom *>(room)->isSpace()) {
+                    connect(room, &Quotient::Room::changed, this, [this]() {
+                        refreshModel();
+                    });
+                }
             }
             if (children[i].childrenState.size() > 0) {
                 auto job = m_space->connection()->callApi<Quotient::GetSpaceHierarchyJob>(children[i].roomId, Quotient::none, Quotient::none, 1);

src/models/spacechildsortfiltermodel.cpp

@@ -60,4 +60,65 @@ bool SpaceChildSortFilterModel::filterAcceptsRow(int sourceRow, const QModelInde
     return true;
 }
 
+void SpaceChildSortFilterModel::move(const QModelIndex &currentIndex, const QModelIndex &targetIndex)
+{
+    const auto rootSpace = dynamic_cast<SpaceChildrenModel *>(sourceModel())->space();
+    if (rootSpace == nullptr) {
+        return;
+    }
+
+    const auto connection = rootSpace->connection();
+
+    const auto currentParent = currentIndex.parent();
+    auto targetParent = targetIndex.parent();
+    NeoChatRoom *currentParentSpace = nullptr;
+    if (!currentParent.isValid()) {
+        currentParentSpace = rootSpace;
+    } else {
+        currentParentSpace = static_cast<NeoChatRoom *>(connection->room(currentParent.data(SpaceChildrenModel::RoomIDRole).toString()));
+    }
+    NeoChatRoom *targetParentSpace = nullptr;
+    if (!targetParent.isValid()) {
+        targetParentSpace = rootSpace;
+    } else {
+        targetParentSpace = static_cast<NeoChatRoom *>(connection->room(targetParent.data(SpaceChildrenModel::RoomIDRole).toString()));
+    }
+    // If both parents are not resolvable to a room object we don't have the permissions
+    // required for this action.
+    if (currentParentSpace == nullptr || targetParentSpace == nullptr) {
+        return;
+    }
+
+    const auto currentRow = currentIndex.row();
+    auto targetRow = targetIndex.row();
+
+    const auto moveRoomId = currentIndex.data(SpaceChildrenModel::RoomIDRole).toString();
+    auto targetRoom = static_cast<NeoChatRoom *>(connection->room(targetIndex.data(SpaceChildrenModel::RoomIDRole).toString()));
+    // If the target room is a space, assume we want to drop the room into it.
+    if (targetRoom != nullptr && targetRoom->isSpace()) {
+        targetParent = targetIndex;
+        targetParentSpace = targetRoom;
+        targetRow = rowCount(targetParent);
+    }
+
+    const auto newRowCount = rowCount(targetParent) + (currentParentSpace != targetParentSpace ? 1 : 0);
+    for (int i = 0; i < newRowCount; i++) {
+        if (currentParentSpace == targetParentSpace && i == currentRow) {
+            continue;
+        }
+
+        targetParentSpace->setChildOrder(index(i, 0, targetParent).data(SpaceChildrenModel::RoomIDRole).toString(),
+                                         QString::number(i > targetRow ? i + 1 : i, 36));
+
+        if (i == targetRow) {
+            if (currentParentSpace != targetParentSpace) {
+                currentParentSpace->removeChild(moveRoomId, true);
+                targetParentSpace->addChild(moveRoomId, true, false, false, QString::number(i + 1, 36));
+            } else {
+                targetParentSpace->setChildOrder(currentIndex.data(SpaceChildrenModel::RoomIDRole).toString(), QString::number(i + 1, 36));
+            }
+        }
+    }
+}
+
 #include "moc_spacechildsortfiltermodel.cpp"

src/models/spacechildsortfiltermodel.h

@@ -46,6 +46,8 @@ protected:
      */
     bool filterAcceptsRow(int sourceRow, const QModelIndex &sourceParent) const override;
 
+    Q_INVOKABLE void move(const QModelIndex &currentIndex, const QModelIndex &targetIndex);
+
 Q_SIGNALS:
     void filterTextChanged();
 

src/neochatroom.cpp

@@ -1329,7 +1329,7 @@ bool NeoChatRoom::childrenHaveHighlightNotifications() const
     return SpaceHierarchyCache::instance().spaceHasHighlightNotifications(id());
 }
 
-void NeoChatRoom::addChild(const QString &childId, bool setChildParent, bool canonical, bool suggested)
+void NeoChatRoom::addChild(const QString &childId, bool setChildParent, bool canonical, bool suggested, const QString &order)
 {
     if (!isSpace()) {
         return;
@@ -1337,7 +1337,9 @@ void NeoChatRoom::addChild(const QString &childId, bool setChildParent, bool can
     if (!canSendEvent("m.space.child"_ls)) {
         return;
     }
-    setState("m.space.child"_ls, childId, QJsonObject{{QLatin1String("via"), QJsonArray{connection()->domain()}}, {"suggested"_ls, suggested}});
+    setState("m.space.child"_ls,
+             childId,
+             QJsonObject{{QLatin1String("via"), QJsonArray{connection()->domain()}}, {"suggested"_ls, suggested}, {"order"_ls, order}});
 
     if (setChildParent) {
         if (auto child = static_cast<NeoChatRoom *>(connection()->room(childId))) {
@@ -1403,6 +1405,28 @@ void NeoChatRoom::toggleChildSuggested(const QString &childId)
     }
 }
 
+void NeoChatRoom::setChildOrder(const QString &childId, const QString &order)
+{
+    if (!isSpace()) {
+        return;
+    }
+    if (!canSendEvent("m.space.child"_ls)) {
+        return;
+    }
+    if (const auto childEvent = currentState().get("m.space.child"_ls, childId)) {
+        auto content = childEvent->contentJson();
+        if (!content.contains("via"_ls)) {
+            return;
+        }
+        if (content.value("order"_ls).toString() == order) {
+            return;
+        }
+
+        content.insert("order"_ls, order);
+        setState("m.space.child"_ls, childId, content);
+    }
+}
+
 PushNotificationState::State NeoChatRoom::pushNotificationState() const
 {
     return m_currentPushNotificationState;

src/neochatroom.h

@@ -560,7 +560,7 @@ public:
      * Will fail if the user doesn't have the required privileges or this room is
      * not a space.
      */
-    Q_INVOKABLE void addChild(const QString &childId, bool setChildParent = false, bool canonical = false, bool suggested = false);
+    Q_INVOKABLE void addChild(const QString &childId, bool setChildParent = false, bool canonical = false, bool suggested = false, const QString &order = {});
 
     /**
      * @brief Remove the given room as a child.
@@ -583,6 +583,8 @@ public:
      */
     Q_INVOKABLE void toggleChildSuggested(const QString &childId);
 
+    void setChildOrder(const QString &childId, const QString &order = {});
+
     bool isInvite() const;
 
     bool readOnly() const;

src/qml/SpaceHierarchyDelegate.qml

@@ -18,6 +18,7 @@ Item {
     required property bool expanded
     required property int hasChildren
     required property int depth
+    required property int row
     required property string roomId
     required property string displayName
     required property url avatarUrl
@@ -36,10 +37,17 @@ Item {
     signal createRoom
 
     Delegates.RoundedItemDelegate {
-        anchors.centerIn: root
+        id: mainDelegate
+        property int row: root.row
+
+        anchors.horizontalCenter: root.horizontalCenter
+        anchors.verticalCenter: root.verticalCenter
         width: sizeHelper.currentWidth
 
+        highlighted: dropArea.containsDrag
+
         contentItem: RowLayout {
+            z: 1
             spacing: Kirigami.Units.largeSpacing
 
             RowLayout {
@@ -140,15 +148,55 @@ Item {
             }
         }
 
-        TapHandler {
-            onTapped: {
+        MouseArea {
+            id: dragArea
+            anchors.fill: parent
+
+            drag.target: mainDelegate
+            drag.axis: Drag.YAxis
+
+            drag.onActiveChanged: {
+                if (!dragArea.drag.active) {
+                    mainDelegate.Drag.drop();
+                }
+            }
+
+            onClicked: {
                 if (root.isSpace) {
-                    root.treeView.toggleExpanded(row);
+                    root.treeView.toggleExpanded(root.row);
                 } else {
                     RoomManager.resolveResource(root.roomId, root.isJoined ? "" : "join");
                 }
             }
         }
+
+        states: [
+            State {
+                when: mainDelegate.Drag.active && root.parentRoom.canSendState("m.space.child")
+                ParentChange {
+                    target: mainDelegate
+                    parent: root.treeView
+                }
+
+                AnchorChanges {
+                    target: mainDelegate
+                    anchors.horizontalCenter: undefined
+                    anchors.verticalCenter: undefined
+                }
+            }
+        ]
+
+        Drag.active: dragArea.drag.active
+        Drag.hotSpot.x: mainDelegate.width / 2
+        Drag.hotSpot.y: Kirigami.Units.smallSpacing
+    }
+
+    DropArea {
+        id: dropArea
+        anchors.fill: parent
+        onDropped: (drag) => {
+            root.treeView.model.move(root.treeView.index(drag.source.row, 0), root.treeView.index(root.row, 0))
+        }
     }
 
     DelegateSizeHelper {