Arduino - write script/diagram for Arduino project (simple)

Arduino Project - Window motor for house open/close Write a script which will allow a "Dry Contact" / "Voltage Free" signal to operate one (1-Open) of two (2-Close) non latching push button switch (model Clipsal 30PB). Once the (open) button is pressed the Arduino will run for a set time (adjustable) and then stop. If the (close) button is pressed then the next active will run for same time and stop the (open) command. This program can then be multiplied to operate 20x sets of (open/close) if necessary. Also, I would like an external signal input for a rain sensor. This will be another dry contact signal. When this signal is active then the (close) is run and then system is locked out until the (rain) is off when the Arduino goes back to normal. Any questions please ask.