Power Assist Brake Hoses, Lines/piping, And Fittings problems of the 1999 GMC Jimmy

I was just getting ready to leave the car wash. I pressed the brake padal to put the truck in gear, a second later the padal went to the floor, thought it was air in the line. Tried a few more times then got out of the truck to look for the leak, found (steel line) drivers side rusted. Had truck towed to shop, as I could not drive it. They found heavy rust on all brake lines in the front, the control arms also have heavy rust. Thank god I was not in traffic as I am sure I would have crashed. The shop is replacing all front brake lines and are going to inspect all other lines all brake lines to back, all fuel lines. Parking brake failed as well. How did this truck pass nys inspection? truck was purchased 3/30/2006 from dealer facility #7096646 a&a used car sales inc. 969 sunrise hwy,brightwaters,NY 11706 nys inspected by station 7099758.