how to create a strategy where when the supertrend turns to buy mode and the reference high is marked at the time of supertrend turning to buy mode. But still the actual buy will come only if the high is taken out on the upper side. Similarly when the supertrend turns to sell mode and the reference low is marked at the time of supertrend turning to sell mode. But still the actual buy will come only if the low is taken out on the lower side.