(require "circuit-simulator.ss")
(require "test-stuff.ss")

(define-syntax capturing-output
  (syntax-rules ()
    ((with-display-output e1 e2 ...)
     (let ((port (open-output-string)))
       (parameterize ((current-output-port port))
         (begin e1 e2 ...))
       (get-output-string port)))))


;; An assertion that checks to see if the output matches what we
;; expected.
(define-simple-assertion (assert-display-output e x)
  (let ((output (capturing-output x)))
    (equal? e output)))


(define circuit-simulator-tests
  (make-test-suite
   "circuit simulator tests"

   (make-test-case
    "simple construction from the book"
    (let ((a (make-wire))
          (b (make-wire))
          (c (make-wire))
          (d (make-wire))
          (e (make-wire))
          (s (make-wire)))      
      (assert-equal? 'ok (or-gate a b d))
      (assert-equal? 'ok (and-gate a b c))
      (assert-equal? 'ok (inverter c e))
      (assert-equal? 'ok (and-gate d e s)))    
    )


   (make-test-case
    "probing"
    (let ((input-1 (make-wire))
          (input-2 (make-wire))
          (sum (make-wire))
          (carry (make-wire)))
      (assert-display-output "\nsum 0  New-value = 0"
                             (probe 'sum sum))
      (assert-display-output "\ncarry 0  New-value = 0"
                             (probe 'carry carry))
      (assert-equal? 'ok (half-adder input-1 input-2 sum carry))
      (assert-equal? 'done (set-signal! input-1 1))
      (assert-display-output "\nsum 8  New-value = 1" (propagate))))
      
      
   ))
   
(test/text-ui circuit-simulator-tests)