Line drawing

Using a click 2 move script I've found troubles when hitting a wall, it's strange and I simply want it to stop right before touching the wall. I know that using the Debug.LineDraw will make a line and goes through the wall, is there a way to use that or anything like it to detect if the player is close enough and also looking at the wall. I want it to stop when it's facing the wall(and close enough), but move around when not facing the wall. Thanks for any help you can give! :D