Basically I use an indicator that notifies me of a trend change. When price is trending up I get a buy signal. When price is trending down I get a sell signal. 

As I trade those signals, I'd like a script to run that closes the trades based on the trend indicator changing.

For example, if I placed a buy and the current trend is  up, I'd want the script to close that trade when the next down signal is given and vice versa.

I want to be able to run this on multiple pairs/charts.

Any questions let me know.