public void CheckAndPerformBackupRevert(Message <D> LatestEditsReceived)
{
if (LatestEditsReceived == null || LatestEditsReceived.Diffs.Where(v => v.Version >= Shadow.PeerVersion).Count() == 0)
{
return;
}
// 4 : Check whether our shadow versions are out of sync and we need to rebase to the version in BackupShadow
if (Shadow.PeerVersion != LatestEditsReceived.Diffs.Select(d => d.Version).Min() || Shadow.Version != LatestEditsReceived.SenderPeerVersion) // Only do this if the message has edits in, otherwise this could be a missed message that can still be processed as is in historic order without clearing and rediffing
{
if (BackupShadow.PeerVersion == Shadow.PeerVersion && BackupShadow.Version == Shadow.Version)
{
throw new Exception("Attempting to revert to backup, but already reverted; DiffSyncer is unrecoverable");
}
// Something is wrong e.g. missing packet. Return shadow to backup shadow which should be synced on both sides, and we can issue a new sync against that.
Shadow = new ShadowState <PATCHER, D, S>(BackupShadow.StateObject);
Shadow.PeerVersion = BackupShadow.PeerVersion;
Shadow.Version = BackupShadow.Version;
Live.Version = Shadow.Version;
UnconfirmedEdits.Diffs.Clear();
//Live.Version = Shadow.Version;
}
}
/// <summary>
/// Initialize with a shadow that isn't the same as live. Useful when starting a session where
/// we may not be able to tell the peer what the initial state is, but the server can initialize
/// with a default state.
/// </summary>
/// <param name="o"></param>
/// <param name="shadow"></param>
public void Initialize(PATCHER live, PATCHER shadow, PATCHER backupshadow)
{
Live = new LiveState <PATCHER, D, S>(live);
Shadow = new ShadowState <PATCHER, D, S>(shadow);
BackupShadow = new BackupShadowState <PATCHER, D, S>(backupshadow);
}