Clean up add existing to space dialog and include DMs in it too

src/components/views/dialogs/AddExistingToSpaceDialog.tsx

@@ -57,21 +57,22 @@ const AddExistingToSpaceDialog: React.FC<IProps> = ({ matrixClient: cli, space,
 
     const existingSubspaces = SpaceStore.instance.getChildSpaces(space.roomId);
     const existingSubspacesSet = new Set(existingSubspaces);
-    const spaces = SpaceStore.instance.getSpaces().filter(s => {
-        return !existingSubspacesSet.has(s) // not already in space
-            && space !== s // not the top-level space
-            && selectedSpace !== s // not the selected space
-            && s.name.toLowerCase().includes(lcQuery); // contains query
-    });
+    const existingRoomsSet = new Set(SpaceStore.instance.getChildRooms(space.roomId));
 
-    const existingRooms = SpaceStore.instance.getChildRooms(space.roomId);
-    const existingRoomsSet = new Set(existingRooms);
-    const rooms = cli.getVisibleRooms().filter(room => {
-        return !existingRoomsSet.has(room) // not already in space
-            && !room.isSpaceRoom() // not a space itself
-            && room.name.toLowerCase().includes(lcQuery) // contains query
-            && !DMRoomMap.shared().getUserIdForRoomId(room.roomId); // not a DM
-    });
+    const [spaces, rooms, dms] = cli.getVisibleRooms().reduce((arr, room) => {
+        if (room.getMyMembership() !== "join") return arr;
+        if (!room.name.toLowerCase().includes(lcQuery)) return arr;
+
+        if (room.isSpaceRoom()) {
+            if (room !== space && room !== selectedSpace && !existingSubspacesSet.has(room)) {
+                arr[0].push(room);
+            }
+        } else if (!existingRoomsSet.has(room) && selectedSpace.joinRule() !== "public") {
+            // Only show DMs for non-public spaces as they make very little sense in spaces other than "Just Me" ones.
+            arr[DMRoomMap.shared().getUserIdForRoomId(room.roomId) ? 2 : 1].push(room);
+        }
+        return arr;
+    }, [[], [], []]);
 
     const [busy, setBusy] = useState(false);
     const [error, setError] = useState("");
@@ -172,7 +173,28 @@ const AddExistingToSpaceDialog: React.FC<IProps> = ({ matrixClient: cli, space,
                 </div>
             ) : null }
 
-            { spaces.length + rooms.length < 1 ? <span className="mx_AddExistingToSpaceDialog_noResults">
+            { dms.length > 0 ? (
+                <div className="mx_AddExistingToSpaceDialog_section">
+                    <h3>{ _t("Direct Messages") }</h3>
+                    { dms.map(space => {
+                        return <Entry
+                            key={space.roomId}
+                            room={space}
+                            checked={selectedToAdd.has(space)}
+                            onChange={(checked) => {
+                                if (checked) {
+                                    selectedToAdd.add(space);
+                                } else {
+                                    selectedToAdd.delete(space);
+                                }
+                                setSelectedToAdd(new Set(selectedToAdd));
+                            }}
+                        />;
+                    }) }
+                </div>
+            ) : null }
+
+            { spaces.length + rooms.length + dms.length < 1 ? <span className="mx_AddExistingToSpaceDialog_noResults">
                 { _t("No results") }
             </span> : undefined }
         </AutoHideScrollbar>