Pine Script

Hi, I'd like a pine script that will backtest any timeframe I choose and will buy and sell on each EMA (Exponential moving average) crossover of the 9 line and the 55 line lengths (i.e. buy on 9 going above 55 and sell when 55 goes above 9.). The three inputs I'd like to be able to control are: 1/ The period of time I'm running the back test for (i.e. between two dates). 2/ The time frame I'm running the back test on (e.g. 5 minutes, 4 hours or whatever I choose). 3/The point at which we buy or sell measured by the number of bars past the crossover. 4/ The amount of funds that have been invested.