Belt / compressor problems

I started my blazer the other day and it was making a really loud squealing noise and i let it run for about 10-15 seconds and it was smoking thick and greyish i believe... Then the squealing stopped and i my belt was snapped.. so I replaced the serp belt today and started it back up and noticed a couple sparks comin out of the compressor.. the top left unit if your looking directly at the engine.. the top right thing the belt is connected to. This is a 92 s10 blazer any ideas what might be wrong or how to fix it?

With the engine cold, remove the belt and turn the pulleys by hand..if they feel rough or don't turn freely, then that is your problem.

So if they don't turn freely or they turn roughly I need a whole new unit for each thing that doesn't operate correctly? .. gettin scared here hehe