Arduino and Unity Project interfacing questions

I have created a game like whack a mole in unity using UI buttons. The game works fine with mouse click as the input controller. My goal is to use an FSR(force sensitive resistor) to act as the button to complete the action as a mouse click would. My problem is trying to get arduino and unity to communicate to each other and Mainly how to implement the code to perform the task.

I might suggest UDuino