The hard brake pedal is due to the high idle. You have reduced engine vacuum at high rpm's and lower or no vacuum assist in the brakes. You may need to reset your throttle position sensor or replace it altogether. If the tps is bad it will run at a high idle all the time.
As Tangofox said, go for the brake booster hose. Having either end of that hose disconnected will result in your exact symptom. This is the large diameter rubber hose that connects the power brake booster (on the driver's side firewall) to the intake manifold where it gets its vacuum which powers the booster.
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