public ITrackingToken AdvancedTo(ITrackingToken newToken)
{
if ((newToken.Covers(IWrappedToken.UnwrapUpperBound(_tokenAtReset)) &&
!_tokenAtReset.Covers(IWrappedToken.UnwrapLowerBound(newToken))))
{
// we're done replaying
// if the token at reset was a wrapped token itself, we'll need to use that one to maintain progress.
return(_tokenAtReset is IWrappedToken wrappedToken?wrappedToken.AdvancedTo(newToken) : newToken);
}
if (_tokenAtReset.Covers(IWrappedToken.UnwrapLowerBound(newToken)))
{
// we're still well behind
return(new ReplayToken(_tokenAtReset, newToken, true));
}
// we're getting an event that we didn't have before, but we haven't finished replaying either
if (_tokenAtReset is IWrappedToken token)
{
return(new ReplayToken(token.UpperBound(newToken),
token.AdvancedTo(newToken), false));
}
return(new ReplayToken(_tokenAtReset.UpperBound(newToken), newToken, false));
}
public static ITrackingToken CreateReplayToken(ITrackingToken tokenAtReset, ITrackingToken?startPosition)
{
while (true)
{
if (tokenAtReset is ReplayToken token)
{
tokenAtReset = token._tokenAtReset;
continue;
}
return(startPosition != null && startPosition.Covers(IWrappedToken.UnwrapLowerBound(tokenAtReset)) ?
startPosition : new ReplayToken(tokenAtReset, startPosition));
}
}
public static long?GetTokenAtReset(ITrackingToken trackingToken)
{
return(IWrappedToken.Unwrap <ReplayToken>(trackingToken)?.GetTokenAtReset().Position());
}
public static bool IsReplay(ITrackingToken trackingToken)
{
return(IWrappedToken.Unwrap <ReplayToken>(trackingToken)?.IsReplay() ?? false);
}
public R?Unwrap <R>() where R : class, ITrackingToken
{
return(this as R ?? IWrappedToken.Unwrap <R>(_currentToken));
}
public ITrackingToken UpperBound()
{
return(IWrappedToken.UnwrapUpperBound(_currentToken));
}
