Improve room alias management

lib/connection.cpp

@@ -18,6 +18,7 @@
 
 #include "csapi/account-data.h"
 #include "csapi/capabilities.h"
+#include "csapi/directory.h"
 #include "csapi/joining.h"
 #include "csapi/leaving.h"
 #include "csapi/logout.h"
@@ -1492,6 +1493,23 @@ Room* Connection::roomByAlias(const QString& roomAlias, JoinStates states) const
     return nullptr;
 }
 
+void Connection::mapAlias(const QString& roomId, const QString& alias)
+{
+    auto getRoomIdByAliasJob = callApi<GetRoomIdByAliasJob>(alias);
+    connect(getRoomIdByAliasJob, &BaseJob::success, this, [this, getRoomIdByAliasJob, alias, roomId] {
+        if (!getRoomIdByAliasJob->roomId().isEmpty()) {
+            qWarning(MAIN) << "Alias" << alias << "is already mapped to" << getRoomIdByAliasJob->roomId();
+        } else {
+            callApi<SetRoomAliasJob>(alias, roomId);
+        }
+    });
+}
+
+void Connection::unmapAlias(const QString& alias)
+{
+    callApi<DeleteRoomAliasJob>(alias);
+}
+
 void Connection::updateRoomAliases(const QString& roomId,
                                    const QStringList& previousRoomAliases,
                                    const QStringList& roomAliases)

lib/connection.h

@@ -288,6 +288,21 @@ class QUOTIENT_API Connection : public QObject {
     Q_INVOKABLE Quotient::Room* roomByAlias(
         const QString& roomAlias,
         Quotient::JoinStates states = JoinState::Invite | JoinState::Join) const;
+
+    //! \brief Map an alias to a room ID on the user's current server.
+    //!
+    //! This uses the room alias endpoint from the matrix specification
+    //! https://spec.matrix.org/v1.5/client-server-api/#room-aliases
+    //!
+    //! \note This is different to Room::setLocalAliases and
+    //!       Room::setCanonicalAlias as they can only get the room to publish
+    //!       an alias that is already mapped.
+    //!       i.e. Use this function first to map an alias then Room::setLocalAliases
+    //!       or Room::setCanonicalAlias to publish the alias officially.
+    //! \sa Room::setLocalAliases, Room::setCanonicalAlias
+    Q_INVOKABLE void mapAlias(const QString& roomId, const QString& alias);
+    //! Unmap an alias from a room ID on the user's current server.
+    Q_INVOKABLE void unmapAlias(const QString& alias);
     //! \brief Update the internal map of room aliases to IDs
     //!
     //! This is used to maintain the internal index of room aliases.

lib/room.cpp

@@ -2306,9 +2306,27 @@ void Room::setName(const QString& newName)
     setState<RoomNameEvent>(newName);
 }
 
+void Room::mapAlias(const QString& alias) const
+{
+    connection()->mapAlias(id(), alias);
+}
+
 void Room::setCanonicalAlias(const QString& newAlias)
 {
-    setState<RoomCanonicalAliasEvent>(newAlias, altAliases());
+    QString oldCanonicalAlias = canonicalAlias();
+    QStringList newAltAliases = altAliases();
+    // Set the old canonical alias as an alt alias.
+    if (!oldCanonicalAlias.isEmpty()) {
+        newAltAliases.append(oldCanonicalAlias);
+    }
+    // If the new canonical alias is already a published alt alias remove it
+    // otherwise it will be in both lists. The server doesn't prevent this so we
+    // need to handle it.
+    if (newAltAliases.contains(newAlias)) {
+        newAltAliases.removeAll(newAlias);
+    }
+
+    setState<RoomCanonicalAliasEvent>(newAlias, newAltAliases);
 }
 
 void Room::setPinnedEvents(const QStringList& events)
@@ -2317,7 +2335,14 @@ void Room::setPinnedEvents(const QStringList& events)
 }
 void Room::setLocalAliases(const QStringList& aliases)
 {
-    setState<RoomCanonicalAliasEvent>(canonicalAlias(), aliases);
+    // If one of the new alt aliases is the current canonical alias set it to ""
+    // otherwise it will be in both lists. The server doesn't prevent this so we
+    // need to handle it.
+    QString currentCanonicalAlias = canonicalAlias();
+    if (aliases.contains(currentCanonicalAlias)) {
+        currentCanonicalAlias = "";
+    }
+    setState<RoomCanonicalAliasEvent>(currentCanonicalAlias, aliases);
 }
 
 void Room::setTopic(const QString& newTopic)

lib/room.h

@@ -836,10 +836,25 @@ public Q_SLOTS:
                                      const QString& stateKey,
                                      const QJsonObject& contentJson);
     void setName(const QString& newName);
-    void setCanonicalAlias(const QString& newAlias);
+
+    //! \brief Map an alias to this room on the user's current server.
+    //!
+    //! Convenience function to call Connection::mapAlias with this room's ID
+    //! \sa Connection::mapAlias
+    Q_INVOKABLE void mapAlias(const QString& alias) const;
+    //! \brief Publish the given alias as the room's canonical alias.
+    //!
+    //! The alias that is published must already have been mapped to the room
+    //! on the server.
+    //! \sa Room::mapAlias
+    Q_INVOKABLE void setCanonicalAlias(const QString& newAlias);
     void setPinnedEvents(const QStringList& events);
-    /// Set room aliases on the user's current server
-    void setLocalAliases(const QStringList& aliases);
+    /// \brief Publish list of alt aliases for the room on the user's current server.
+    //!
+    //! The aliases that are published must already have been mapped to the room
+    //! on the server.
+    //! \sa Room::mapAlias
+    Q_INVOKABLE void setLocalAliases(const QStringList& aliases);
     void setTopic(const QString& newTopic);
 
     /// You shouldn't normally call this method; it's here for debugging