Revert "Always offer avatars to friend who come online"

This reverts commit e30fb4d919.

src/net/avatarbroadcaster.cpp

@@ -24,6 +24,7 @@
 #include <QDebug>
 
 QByteArray AvatarBroadcaster::avatarData;
+QMap<uint32_t, bool> AvatarBroadcaster::friendsSentTo;
 
 static QMetaObject::Connection autoBroadcastConn;
 static auto autoBroadcast = [](uint32_t friendId, Status)
@@ -34,6 +35,7 @@ static auto autoBroadcast = [](uint32_t friendId, Status)
 void AvatarBroadcaster::setAvatar(QByteArray data)
 {
     avatarData = data;
+    friendsSentTo.clear();
 
     QVector<uint32_t> friends = Core::getInstance()->getFriendList();
     for (uint32_t friendId : friends)
@@ -42,9 +44,12 @@ void AvatarBroadcaster::setAvatar(QByteArray data)
 
 void AvatarBroadcaster::sendAvatarTo(uint32_t friendId)
 {
+    if (friendsSentTo.contains(friendId) && friendsSentTo[friendId])
+        return;
     if (!Core::getInstance()->isFriendOnline(friendId))
         return;
     Core::getInstance()->sendAvatarFile(friendId, avatarData);
+    friendsSentTo[friendId] = true;
 }
 
 void AvatarBroadcaster::enableAutoBroadcast(bool state)

src/net/avatarbroadcaster.h

@@ -24,7 +24,9 @@
 #include <QByteArray>
 #include <QMap>
 
-/// Takes care of broadcasting avatar changes to our friends
+/// Takes care of broadcasting avatar changes to our friends in a smart way
+/// Cache a copy of our current avatar and friends who have received it
+/// so we don't spam avatar transfers to a friend who already has it.
 class AvatarBroadcaster
 {
 private:
@@ -40,6 +42,7 @@ public:
 
 private:
     static QByteArray avatarData;
+    static QMap<uint32_t, bool> friendsSentTo;
 };
 
 #endif // AVATARBROADCASTER_H