Mid 2012 OSX Yosemite wont turn on

Hey guys, bit of an issue I'm hoping you can help with.

THe the other day my MacBook Pro mid 2012 model running Yosemite was turning itself off and on again, when It would do so it would come up with a message saying to press any key or wait for it to start up

it ended up getting to the desktop, I did a small update then everything seemed ok

tthen tonight it did the same thing, until it wouldn't turn back on.

WHen its it's plugged isn't the MagSafe it shows its responding to the charger, ive tried to do the cmd power start thing and the cmd option and p r start nothing is working

WHen i press the the power button it makes a click sound now and doesnt boot up.

Someone please help with whith any sort of knowledge