I want an indicator turned to E.A

I have an indicator which I want a proffessional programmer to convert to an E.A  Here is how I want it to be done:once the indicator generates a buy or sell signal the E.A should buy or sell at that market price....The closing and opening of orders is that if the E.A had earlier generated a buy order and after one day the E.A generates a sell order the EA will first close the buy order before placing  a sell order...............................N/B  for risk management here is how I want it to be this particular indicator once it generates a buy or sell signal it normally displays an arrow in the chart but sometimes it may generate a buy or sell signal but after sometime the buy or sell signal disappers so if we had a buy order in the market and the signal of buy disappers  then the E.A should close the order regardless if it's in profit or loss