#:use-module (srfi srfi-9 gnu)
#:use-module (ice-9 q)
#:use-module (ice-9 match)
+ #:use-module (ice-9 receive)
#:export (make-agenda
agenda?
agenda-queue agenda-prompt-tag
time-segment?
time-segment-time time-segment-queue
- time-< time-=
+ time-< time-= time-<=
make-schedule
schedule-add! schedule-empty?
+ schedule-segments
+
+ schedule-segments-split schedule-extract-until!
make-port-mapping
port-mapping-set! port-mapping-remove!
(define (time-segment-right-format time)
(match time
;; time is already a cons of second and microsecnd
- (((? integer? s) (? integer? u)) time)
+ (((? integer? s) . (? integer? u)) time)
;; time was just an integer (just the second)
((? integer? _) (cons time 0))
(_ (throw 'invalid-time "Invalid time" time))))
(and (= (car time1) (car time2))
(= (cdr time1) (cdr time2))))
-(define (make-schedule)
- '())
+(define (time-<= time1 time2)
+ (or (time-< time1 time2)
+ (time-= time1 time2)))
+
+(define-record-type <schedule>
+ (make-schedule-intern segments)
+ schedule?
+ (segments schedule-segments set-schedule-segments!))
+
+(define* (make-schedule #:optional segments)
+ (make-schedule-intern (or segments '())))
+;; TODO: This code is reasonably easy to read but it
+;; mutates AND is worst case of O(n) in both space and time :(
+;; but at least it'll be reasonably easy to refactor to
+;; a more functional setup?
(define (schedule-add! time proc schedule)
(let ((time (time-segment-right-format time)))
- (define (belongs-before? segments)
- (or (null? segments)
- (error))
- )
-
- ;; Find and add a schedule segment
- (error)))
+ (define (new-time-segment)
+ (let ((new-segment
+ (make-time-segment time)))
+ (enq! (time-segment-queue new-segment) proc)
+ new-segment))
+ (define (loop segments)
+ (define (segment-equals-time? segment)
+ (time-= time (time-segment-time segment)))
+
+ (define (segment-more-than-time? segment)
+ (time-< time (time-segment-time segment)))
+
+ ;; We could switch this out to be more mutate'y
+ ;; and avoid the O(n) of space... is that over-optimizing?
+ (match segments
+ ;; If we're at the end of the list, time to make a new
+ ;; segment...
+ ('() (cons (new-time-segment) '()))
+ ;; If the segment's time is exactly our time, good news
+ ;; everyone! Let's append our stuff to its queue
+ (((? segment-equals-time? first) rest ...)
+ (enq! (time-segment-queue first) proc)
+ segments)
+ ;; If the first segment is more than our time,
+ ;; ours belongs before this one, so add it and
+ ;; start consing our way back
+ (((? segment-more-than-time? first) rest ...)
+ (cons (new-time-segment) segments))
+ ;; Otherwise, build up recursive result
+ ((first rest ... )
+ (cons first (loop rest)))))
+ (set-schedule-segments!
+ schedule
+ (loop (schedule-segments schedule)))))
(define (schedule-empty? schedule)
- (eq? schedule '()))
+ (eq? (schedule-segments schedule) '()))
+
+(define (schedule-segments-split schedule time)
+ "Does a multiple value return of time segments before/at and after TIME"
+ (let ((time (time-segment-right-format time)))
+ (define (segment-is-now? segment)
+ (time-= (time-segment-time segment) time))
+ (define (segment-is-before-now? segment)
+ (time-< (time-segment-time segment) time))
+
+ (let loop ((segments-before '())
+ (segments-left (schedule-segments schedule)))
+ (match segments-left
+ ;; end of the line, return
+ ('()
+ (values (reverse segments-before) '()))
+
+ ;; It's right now, so time to stop, but include this one in before
+ ;; but otherwise return
+ (((? segment-is-now? first) rest ...)
+ (values (reverse (cons first segments-before)) rest))
+
+ ;; This is prior or at now, so add it and keep going
+ (((? segment-is-before-now? first) rest ...)
+ (loop (cons first segments-before) rest))
+
+ ;; Otherwise it's past now, just return what we have
+ (segments-after
+ (values segments-before segments-after))))))
+
+(define (schedule-extract-until! schedule time)
+ "Extract all segments until TIME from SCHEDULE, and pop old segments off"
+ (receive (segments-before segments-after)
+ (schedule-segments-split schedule time)
+ (set-schedule-segments! schedule segments-after)
+ segments-before))
\f