@startuml
skinparam BackgroundColor F0F0F0

start


:pass data to ATStream via write;

if (isReady) then 
	:return error (could be call reset, to get new data);
	Stop;
endif

:add new data to buffer;


    if (AT Return at the begin) then (yes)	
		:Set "Return at the begin" flag;
		if (Expected line count= 0) then (yes)
		:(isReady=true);
			Stop;
		endif
	else (no)
	endif
	
	:Count lines from last position;
	
    if ("Return at the begin" flag is set) then (yes)
	   if (More lines then expected) then (yes)
	   :(isReady=true);
		Stop;
	   endif
	else (no)
	 if (AT Return at the end) then (yes)
		:(isReady=true);
		Stop;
	 endif
	endif
	
	:Stream still wait for data (isReady=false);
	Stop;
	







@enduml