Support the order parameter in m.space.child events

Support the order parameter in m.space.child events, with the exception of always putting spaces higher than non-spaces

see https://spec.matrix.org/v1.8/client-server-api/#ordering-of-children-within-a-space for the spec algorithm

src/models/spacechildrenmodel.cpp

@@ -244,6 +244,20 @@ QVariant SpaceChildrenModel::data(const QModelIndex &index, int role) const
         }
         return QVariant::fromValue(nullptr);
     }
+    if (role == OrderRole) {
+        if (child->parentItem() == nullptr) {
+            return QString();
+        }
+        const auto childState = child->parentItem()->childStateContent(child);
+        return childState[QLatin1String("order")].toString();
+    }
+    if (role == ChildTimestampRole) {
+        if (child->parentItem() == nullptr) {
+            return QString();
+        }
+        const auto childState = child->parentItem()->childState(child);
+        return childState[QLatin1String("origin_server_ts")].toString();
+    }
 
     return {};
 }
@@ -325,6 +339,8 @@ QHash<int, QByteArray> SpaceChildrenModel::roleNames() const
     roles[IsDeclaredParentRole] = "isDeclaredParent";
     roles[CanRemove] = "canRemove";
     roles[ParentRoomRole] = "parentRoom";
+    roles[OrderRole] = "order";
+    roles[ChildTimestampRole] = "childTimestamp";
 
     return roles;
 }

src/models/spacechildrenmodel.h

@@ -51,6 +51,8 @@ public:
         IsDeclaredParentRole,
         CanRemove,
         ParentRoomRole,
+        OrderRole,
+        ChildTimestampRole,
     };
 
     explicit SpaceChildrenModel(QObject *parent = nullptr);

src/models/spacechildsortfiltermodel.cpp

@@ -26,10 +26,27 @@ QString SpaceChildSortFilterModel::filterText() const
 
 bool SpaceChildSortFilterModel::lessThan(const QModelIndex &source_left, const QModelIndex &source_right) const
 {
-    if (!source_left.data(SpaceChildrenModel::IsSpaceRole).toBool() && source_right.data(SpaceChildrenModel::IsSpaceRole).toBool()) {
+    if (source_left.data(SpaceChildrenModel::IsSpaceRole).toBool() && source_right.data(SpaceChildrenModel::IsSpaceRole).toBool()) {
+        if (!source_left.data(SpaceChildrenModel::OrderRole).toString().isEmpty() && !source_right.data(SpaceChildrenModel::OrderRole).toString().isEmpty()) {
+            return QString::compare(source_left.data(SpaceChildrenModel::OrderRole).toString(), source_right.data(SpaceChildrenModel::OrderRole).toString())
+                < 0;
+        }
+        return source_left.data(SpaceChildrenModel::ChildTimestampRole).toDateTime() > source_right.data(SpaceChildrenModel::ChildTimestampRole).toDateTime();
+    }
+    if (source_left.data(SpaceChildrenModel::IsSpaceRole).toBool()) {
+        return true;
+    } else if (source_right.data(SpaceChildrenModel::IsSpaceRole).toBool()) {
         return false;
     }
-    return true;
+    if (!source_left.data(SpaceChildrenModel::OrderRole).toString().isEmpty() && !source_right.data(SpaceChildrenModel::OrderRole).toString().isEmpty()) {
+        return QString::compare(source_left.data(SpaceChildrenModel::OrderRole).toString(), source_right.data(SpaceChildrenModel::OrderRole).toString()) < 0;
+    }
+    if (!source_left.data(SpaceChildrenModel::OrderRole).toString().isEmpty()) {
+        return true;
+    } else if (!source_right.data(SpaceChildrenModel::OrderRole).toString().isEmpty()) {
+        return false;
+    }
+    return source_left.data(SpaceChildrenModel::ChildTimestampRole).toDateTime() > source_right.data(SpaceChildrenModel::ChildTimestampRole).toDateTime();
 }
 
 bool SpaceChildSortFilterModel::filterAcceptsRow(int sourceRow, const QModelIndex &sourceParent) const

src/models/spacetreeitem.cpp

@@ -141,6 +141,22 @@ bool SpaceTreeItem::isSpace() const
     return m_isSpace;
 }
 
+QJsonObject SpaceTreeItem::childState(const SpaceTreeItem *child) const
+{
+    if (child == nullptr) {
+        return {};
+    }
+    if (child->parentItem() != this) {
+        return {};
+    }
+    for (const auto &childState : m_childStates) {
+        if (childState->stateKey() == child->id()) {
+            return childState->fullJson();
+        }
+    }
+    return {};
+}
+
 QJsonObject SpaceTreeItem::childStateContent(const SpaceTreeItem *child) const
 {
     if (child == nullptr) {

src/models/spacetreeitem.h

@@ -125,6 +125,11 @@ public:
      */
     bool isSpace() const;
 
+    /**
+     * @brief Return the m.space.child stripped state Json for the given child.
+     */
+    QJsonObject childState(const SpaceTreeItem *child) const;
+
     /**
      * @brief Return the m.space.child state event content for the given child.
      */