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-rw-r--r--module/vcalendar/recurrence/generate.scm137
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diff --git a/module/vcalendar/recurrence/generate.scm b/module/vcalendar/recurrence/generate.scm
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--- a/module/vcalendar/recurrence/generate.scm
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@@ -1,137 +0,0 @@
-(define-module (vcalendar recurrence generate)
- #:use-module (srfi srfi-19) ; Datetime
- #:use-module (srfi srfi-19 util)
- #:use-module (srfi srfi-19 setters)
- #:use-module (srfi srfi-26) ; Cut
- #:use-module (srfi srfi-41) ; Streams
- #:use-module (ice-9 match)
-
- #:use-module (util)
- #:use-module (vcalendar)
- #:use-module (vcalendar timezone)
- #:use-module (vcalendar recurrence internal)
- #:use-module (vcalendar recurrence parse)
-
- #:export (generate-recurrence-set)
- )
-
-;;; TODO implement
-;;; EXDATE and RDATE
-
-;;; EXDATE (3.8.5.1)
-;;; comma sepparated list of dates or datetimes.
-;;; Can have TZID parameter
-;;; Specifies list of dates that the event should not happen on, even
-;;; if the RRULE say so.
-;;; Can have VALUE field specifiying "DATE-TIME" or "DATE".
-
-;;; RDATE (3.8.5.2)
-;;; Comma sepparated list of dates the event should happen on.
-;;; Can have TZID parameter.
-;;; Can have VALUE parameter, specyfying "DATE-TIME", "DATE" or "PREIOD".
-;;; PERIOD (see 3.3.9)
-
-(define (seconds-in freq)
- (case freq
- ((SECONDLY) 1)
- ((MINUTELY) 60)
- ((HOURLY) (* 60 60))
- ((DAILY) (* 60 60 24))
- ((WEEKLY) (* 60 60 24 7))))
-
-;; Event x Rule → Event
-;; TODO My current naïve aproach to simple adding a constant time to an event
-;; breaks with time-zones. betwen 12:00 two adjacent days might NOT be 24h.
-;; Specifically, 23h or 25h when going between summer and "normal" time.
-(define (next-event ev r)
- (let* ((e (copy-vcomponent ev))
- (d (time-utc->date
- (attr e 'DTSTART)
- (if (prop (attr* ev 'DTSTART) 'TZID)
- (get-tz-offset e)
- 0))))
-
- (let ((i (interval r)))
- (case (freq r)
- ((SECONDLY) (mod! (second d) = (+ i)))
- ((MINUTELY) (mod! (minute d) = (+ i)))
- ((HOURLY) (mod! (hour d) = (+ i)))
- ((DAILY) (mod! (day d) = (+ i)))
- ((WEEKLY) (mod! (day d) = (+ (* i 7))))
- ((MONTHLY) (mod! (month d) = (+ i)))
- ((YEARLY) (mod! (year d) = (+ i)))))
-
- (set! (attr e 'DTSTART)
- (date->time-utc d))
-
- (when (prop (attr* e 'DTSTART) 'TZID)
- (let ((of (get-tz-offset e)))
- ;; This addition works, but we still get lunch at 13
- (set! (zone-offset d) of)))
-
- (set! (attr e 'DTSTART)
- (date->time-utc d))
-
- (when (attr e 'DTEND)
- (set! (attr e 'DTEND)
- (add-duration (attr e 'DTSTART) (attr e 'DURATION))))
-
- ;; Return
- e))
-
-;; BYDAY and the like depend on the freq?
-;; Line 7100
-;; Table @@ 2430
-;;
-;; Event x Rule → Bool (continue?)
-;; Alternative, monadic solution using <optional>.
-;; @example
-;; (optional->bool
-;; (do (<$> (cut time<=? (attr last 'DTSTART)) (until r))
-;; (<$> (negate zero?) (count r))
-;; (just #t)))
-;; @end example
-(define-stream (recur-event-stream event rule-obj)
- (stream-unfold
-
- ;; Event x Rule → Event
- car
-
- ;; Event x Rule → Bool (continue?)
- (match-lambda
- ((e r)
- (or (and (not (until r)) (not (count r))) ; Never ending
- (and=> (count r) (negate zero?)) ; COUNT
- (and=> (until r) (cut time<=? (attr e 'DTSTART) <>))))) ; UNTIL
-
- ;; Event x Rule → next (Event, Rule)
- (match-lambda
- ((e r)
- (list (next-event e r)
- (if (count r)
- ;; Note that this doesn't modify, since r is immutable.
- (mod! (count r) 1-)
- r ))))
-
- ;; Seed
- (list event rule-obj)))
-
-
-(define (generate-recurrence-set event)
- ;; TODO DURATION might be used for something else, check applicable types
- ;; TODO Far from all events have DTEND
- ;; VTIMEZONE's always lack it.
- (if (not (attr event 'RRULE))
- (stream event)
- (begin
- (when (and (attr event 'DTEND)
- (not (attr event 'DURATION)))
- (set! (attr event "DURATION")
- (time-difference
- (attr event "DTEND")
- (attr event "DTSTART"))))
- (if (attr event "RRULE")
- (recur-event-stream event (parse-recurrence-rule (attr event "RRULE")))
- ;; TODO some events STANDARD and DAYLIGT doesn't have RRULE's, but rather
- ;; just mention the current part. Handle this
- stream-null))))