BUY/SELL Limit EA

How would I go about creating an EA that would allow you to click on the screen and do a buy or sell limit as we can already but also have it set to the time where the mouse curser is. So it would not activate till it hit that time on the screen then if the price was moving up to the buy limit it would trigger ect. Obviously it would not trigger if the ask line was above the point that the buy limit was set. And vice versa.