It's easier to implement on fixed-lens rangefinder cameras. Far more expensive rangefinders such as Leica are unable to do that. Notice how the brightline changes size and it's position in the viewfinder as you focus closer.
The viewfinder is big and bright and fully automatic correction for parallax error. You'll need a flash with a sync cord, though. The leaf type shutter holds up well and you can sync flash at all shutter speeds (1 second to 1/500, if memory serves). It's an excellent camera, quite likely very usable. I've got a couple Auto S2, as well as most other Konica rangefinder cameras made from 1939 to 1989. Pretty good for slides that are 43 years old! Will you still have all your digital image files in 43 years? The shots below were taken with my original Konica Auto S2, Tan Son Nhut AB, Saigon, Vietnam 1968. Note: Minolta has no connection to the manufacture of the camera when it was built. If you have any questions about the camera I'll try to help. Next step would be put a roll of film through it. Try different aperture setting while doing this and you should see it change from wide open to closed down. You should see the shutter open and close and it should do so without hesitation. To check that the shutter and aperture work, set the camera to operate manually, open the camera back, cock the film lever, and press the shutter button while looking through the back of the camera. Mercury batteries have been pretty much banned, but an alternative is a zinc-air battery that supplies the same voltage. These cameras took a 675 mercury cell to power it. To see if the lightmeter works you'll need a battery. Old basic analog style meters can be found pretty cheap now.
It may not work and if it doesn't, the camera will have to be used in manual, as the Auto part of the camera relies on the meter to set the exposure. The most likely problem you may have with it is the lightmeter. I just liked the way they felt and worked for a rangefinder style camera. I now own two of them that I had bought off ebay and use occasionally. It subsequently got stolen from a hotel room in in Okinawa about a year later. The Konica Auto S2 was actually the first 35mm camera I ever owned and bought it in VietNam around 1968.