SETH = Foreign("SET", "High");
SETL = Foreign("SET", "Low");
SETPeak = Peak(SETH , 1 ,1);
SETTruogh = Trough(SETL , 1 ,1);
Uptrend = Cross(SETH , Ref(SETPeak , -1));
Downtrend = Cross(Ref(SETTruogh , -1), SETL );
Uptrend = ExRem(Uptrend , Downtrend );
Downtrend = ExRem(Downtrend , Uptrend );
isUptrend = Flip(Uptrend , Downtrend);

Buy = isUptrend && ...// condition for buy
Sell = !isUptrend && ...// condition for sell