My toilet was working properly before tonight. There was no slow leak sound; nothing.

Now when the handle is pressed, nothing happens. I opened up the tank and found there was no water in the tank. I've been searching the Internet for answers, but haven't found any that address this particular problem.

I realize I can pour water down the toilet to temporarily get to to flush. I want to repair this.

Incidentally, the cut off valve under the toilet doesn't work. It hasn't worked for years. So to shut off the water, I must shut off the main valve in the basement. Since that doesn't shut it off completely, I turn on the basement faucet as a temporary fix.

From what I've read, I think the problem is the fill valve. My current fill valve is a simple looking white plastic part. It's not a FluidMaster brand.