; Model 2a - Continuous Simulation Model
(require (planet "simulation-with-graphics.ss"
                 ("williams" "simulation.plt" 1 0)))
(require (planet "random-source.ss" ("williams" "science.plt")))
(require (planet "random-distributions.ss"
                 ("williams" "science.plt")))

;; Simulation Parameters
(define end-time 720.0)
(define n-pits 7)

; Data collection variables
(define total-ingots 0)
(define wait-time #f)
(define heat-time #f)
(define leave-temp #f)

;;; Model Definition
(define random-sources (make-random-source-vector 4))

(define furnace-set #f)
(define furnace-temp 1500.0)
(define pit #f)

(define (scheduler)
  (let loop ((i 0))
    (schedule now (ingot i))
    (wait (random-exponential (vector-ref random-sources 0) 1.5))
    (loop (+ i 1))))

(define-process (ingot i)
  (let* ((initial-temp (random-flat (vector-ref random-sources 1) 100.0 200.0))
         (heat-coeff (+ (random-gaussian
                         (vector-ref random-sources 2) 0.05 0.01) 0.07))
         (final-temp (random-flat (vector-ref random-sources 3) 800.0 1000.0))
         (current-temp (make-continuous-variable initial-temp))
         (arrive-time (current-simulation-time))
         (start-time #f))
;    (if (= (modulo i 100) 0)
;        (accumulate (variable-history current-temp)))
    (with-resource (pit)
      (set-variable-value! wait-time (- (current-simulation-time) arrive-time))
      (set-insert! furnace-set self)
      (set! start-time (current-simulation-time))
      (work/continuously
        until (>= (variable-value current-temp) final-temp)
        (set-variable-dt!
         current-temp
         (* (- furnace-temp (variable-value current-temp))
            heat-coeff)))
      (set-variable-value! heat-time (- (current-simulation-time) start-time))
      (set-variable-value! leave-temp (variable-value current-temp))
      (set-remove! furnace-set self))
    (if (variable-history current-temp)
        (printf "~a~n" (history-plot (variable-history current-temp)
                                     (format "Ingot ~a Temp History" i))))
    (set! total-ingots (+ total-ingots 1))))

(define (stop-sim)
;  (printf "Report after ~a Simulated Hours - ~a Ingots Processed~n"
;          (current-simulation-time) total-ingots)
;  (printf "~n-- Ingot Waiting Time Statistics --~n")
;  (printf "Mean Wait Time        = ~a~n" (variable-mean wait-time))
;  (printf "Variance              = ~a~n" (variable-variance wait-time))
;  (printf "Maximum Wait Time     = ~a~n" (variable-maximum wait-time))
;  (printf "~n-- Ingot Heating Time Statistics --~n")
;  (printf "Mean Heat Time        = ~a~n" (variable-mean heat-time))
;  (printf "Variance              = ~a~n" (variable-variance heat-time))
;  (printf "Maximum Heat Time     = ~a~n" (variable-maximum heat-time))
;  (printf "Minimum Heat Time     = ~a~n" (variable-minimum heat-time))
;  (printf "~n-- Final Temperature Statistics --~n")
;  (printf "Mean Leave Temp       = ~a~n" (variable-mean leave-temp))
;  (printf "Variance              = ~a~n" (variable-variance leave-temp))
;  (printf "Maximum Leave Temp    = ~a~n" (variable-maximum leave-temp))
;  (printf "Minimum Leave Temp    = ~a~n" (variable-minimum leave-temp))
;  (printf "~a~n"
;          (history-plot (variable-history leave-temp)
;                        "Final Temperature Histogram"))
;  (printf "~n-- Furnace Utilization Statistics --~n")
;  (printf "Mean No. of Ingots    = ~a~n"
;          (variable-mean (set-variable-n furnace-set)))
;  (printf "Variance              = ~a~n"
;          (variable-variance (set-variable-n furnace-set)))
;  (printf "Maximum No. of Ingots = ~a~n"
;          (variable-maximum (set-variable-n furnace-set)))
;  (printf "Minimum No. of Ingots = ~a~n"
;          (variable-minimum (set-variable-n furnace-set)))
;  (printf "~a~n"
;          (history-plot (variable-history (set-variable-n furnace-set))
;                        "Furnace Utilization History"))
  (stop-simulation))

(define (initialize)
  ;; Set continuous simulation settings
  (current-simulation-step-size (/ 1.0 60.0))
  (current-simulation-control #f)
  ;; ---
  (set! total-ingots 0)
  (set! wait-time (make-variable))
  (set! heat-time (make-variable))
  (set! leave-temp (make-variable))
  (set! pit (make-resource n-pits))
  (set! furnace-set (make-set))
  (accumulate (variable-history (set-variable-n furnace-set)))
  (tally (variable-statistics wait-time))
  (tally (variable-statistics heat-time))
  (tally (variable-statistics leave-temp))
  (tally (variable-history leave-temp))
  (schedule (at end-time) (stop-sim))
  (schedule (at 0.0) (scheduler)))

(define (run-simulation)
  (with-new-simulation-environment
    (initialize)
    (start-simulation)))

(do ((i 0 (+ i 1)))
    ((= i 5)(void))
  (run-simulation)
  (collect-garbage))

(require (planet "statistics.ss" ("williams" "science.plt")))
(require (planet "histogram-with-graphics.ss" ("williams" "science.plt")))
(let* ((n 1000)
       (cpu-times (make-vector n))
       (real-times (make-vector n))
       (gc-times (make-vector n)))
  (do ((i 0 (+ i 1)))
      ((= i n)(void))
    (collect-garbage)
    (let-values (((result cpu real gc) (time-apply run-simulation '())))
      (vector-set! cpu-times i cpu)
      (vector-set! real-times i real)
      (vector-set! gc-times i gc))
    (if (= 0 (modulo i 50))
        (printf "~n"))
    (printf "."))
  (printf "~n")
  (do ((i 0 (+ i 1)))
      ((= i n) (void))
    (printf "run ~a: cpu = ~a real = ~a gc = ~a~n"
            i (vector-ref cpu-times i)
            (vector-ref real-times i)
            (vector-ref gc-times i)))
  (printf "CPU:   mean = ~a, variance = ~a~n"
          (mean cpu-times) (variance cpu-times))
  (printf "Real:  mean = ~a, variance = ~a~n"
          (mean real-times) (variance real-times))
  (printf "GC:    mean = ~a, variance = ~a~n"
          (mean gc-times) (variance gc-times))
  ;; Plot histogram of real times
  (let ((h (make-histogram-with-ranges-uniform
            40 (minimum real-times) (maximum real-times))))
    (do ((i 0 (+ i 1)))
        ((= i n)(void))
      (histogram-increment! h (vector-ref real-times i)))
    (let ((snip (histogram-plot h "Histogram of Real Times")))
      (printf "~a~n" snip)
      (send (send snip get-bitmap)
            save-file "histogram.bmp" 'bmp 100))))