diff options
Diffstat (limited to 'modules/calendar-sync-recurrence.el')
| -rw-r--r-- | modules/calendar-sync-recurrence.el | 176 |
1 files changed, 152 insertions, 24 deletions
diff --git a/modules/calendar-sync-recurrence.el b/modules/calendar-sync-recurrence.el index 1cb25636..a3bd4dc4 100644 --- a/modules/calendar-sync-recurrence.el +++ b/modules/calendar-sync-recurrence.el @@ -90,6 +90,9 @@ dropped by `calendar-sync--filter-declined'." (list :recurrence-id (calendar-sync--localize-parsed-datetime recurrence-id-parsed recurrence-id-is-utc recurrence-id-tzid) :recurrence-id-raw recurrence-id + ;; A cancelled override removes its occurrence downstream + ;; rather than rescheduling it. + :cancelled (calendar-sync--event-cancelled-p event-str) :start start-parsed :end end-parsed :summary summary @@ -164,24 +167,30 @@ Compares year, month, day, hour, minute." "Apply EXCEPTIONS to OCCURRENCES list. OCCURRENCES is list of event plists from RRULE expansion. EXCEPTIONS is hash table from `calendar-sync--collect-recurrence-exceptions'. -Returns new list with matching occurrences replaced by exception times." +Returns new list with matching occurrences replaced by exception times. +A cancelled exception (STATUS:CANCELLED override) removes its occurrence +from the list instead of overriding it." (if (or (null occurrences) (null exceptions)) occurrences - (mapcar - (lambda (occurrence) - (let* ((uid (plist-get occurrence :uid)) - (uid-exceptions (and uid (gethash uid exceptions)))) - (if (null uid-exceptions) - occurrence - ;; Check if any exception matches this occurrence - (let ((matching-exception - (cl-find-if (lambda (exc) - (calendar-sync--occurrence-matches-exception-p occurrence exc)) - uid-exceptions))) - (if matching-exception - (calendar-sync--apply-single-exception occurrence matching-exception) - occurrence))))) - occurrences))) + (delq nil + (mapcar + (lambda (occurrence) + (let* ((uid (plist-get occurrence :uid)) + (uid-exceptions (and uid (gethash uid exceptions)))) + (if (null uid-exceptions) + occurrence + ;; Check if any exception matches this occurrence + (let ((matching-exception + (cl-find-if (lambda (exc) + (calendar-sync--occurrence-matches-exception-p occurrence exc)) + uid-exceptions))) + (cond + ((null matching-exception) occurrence) + ;; Cancelled instance: drop it entirely. + ((plist-get matching-exception :cancelled) nil) + (t (calendar-sync--apply-single-exception + occurrence matching-exception))))))) + occurrences)))) ;;; EXDATE (Excluded Date) Handling @@ -291,7 +300,9 @@ OCCURRENCE-DATE should be a list (year month day hour minute second)." (defun calendar-sync--parse-rrule (rrule-str) "Parse RRULE string into plist. -Returns plist with :freq :interval :byday :until :count." +Returns plist with :freq :interval :byday :bysetpos :bymonth :until :count. +BYMONTH keeps only the first value of a comma-separated list -- feeds in +practice emit a single month there." (let ((parts (split-string rrule-str ";")) (result '())) (dolist (part parts) @@ -302,6 +313,8 @@ Returns plist with :freq :interval :byday :until :count." ("FREQ" (setq result (plist-put result :freq (intern (downcase value))))) ("INTERVAL" (setq result (plist-put result :interval (string-to-number value)))) ("BYDAY" (setq result (plist-put result :byday (split-string value ",")))) + ("BYSETPOS" (setq result (plist-put result :bysetpos (string-to-number value)))) + ("BYMONTH" (setq result (plist-put result :bymonth (string-to-number value)))) ("UNTIL" (setq result (plist-put result :until (calendar-sync--parse-timestamp value)))) ("COUNT" (setq result (plist-put result :count (string-to-number value)))))))) ;; Set defaults @@ -389,18 +402,133 @@ BASE-EVENT is the event plist, RRULE is parsed rrule, RANGE is date range." (calendar-sync--log-silently "calendar-sync: WARNING: Hit max iterations (%d) expanding weekly event" max-iterations)) (nreverse occurrences))) +(defun calendar-sync--parse-byday-entry (entry) + "Parse a single RRULE BYDAY ENTRY into a cons (ORDINAL . WEEKDAY). +ENTRY is a string like \"2WE\" (2nd Wednesday), \"-1TU\" (last Tuesday), +or \"SU\" (bare weekday). ORDINAL is nil for a bare weekday. WEEKDAY is +1-7 (Monday = 1). Returns nil for unparseable input." + (when (and (stringp entry) + (string-match "\\`\\(-?[0-9]+\\)?\\([A-Z][A-Z]\\)\\'" entry)) + (let ((ordinal (match-string 1 entry)) + (weekday (calendar-sync--weekday-to-number (match-string 2 entry)))) + (when weekday + (cons (and ordinal (string-to-number ordinal)) weekday))))) + +(defun calendar-sync--byday-days-in-month (year month byday-entries bysetpos) + "Return the sorted day-of-month list BYDAY-ENTRIES select in YEAR/MONTH. +An entry with an ordinal (\"2WE\") resolves directly via +`calendar-sync--nth-weekday-of-month'. A bare entry (\"SU\") expands to +every matching weekday in the month. When BYSETPOS is non-nil it then +selects one day from the combined set (1-based; negative counts from the +end), per RFC 5545 3.8.5.3. Months with no match return nil." + (let ((days '())) + (dolist (entry byday-entries) + (let ((parsed (calendar-sync--parse-byday-entry entry))) + (when parsed + (let ((ordinal (car parsed)) + (weekday (cdr parsed))) + (if ordinal + (let ((day (calendar-sync--nth-weekday-of-month year month weekday ordinal))) + (when day (push day days))) + (let ((n 1) day) + (while (setq day (calendar-sync--nth-weekday-of-month year month weekday n)) + (push day days) + (setq n (1+ n))))))))) + (setq days (sort (delete-dups days) #'<)) + (if (and bysetpos days) + (let* ((total (length days)) + (index (if (> bysetpos 0) bysetpos (+ total bysetpos 1)))) + (if (and (>= index 1) (<= index total)) + (list (nth (1- index) days)) + '())) + days))) + +(defun calendar-sync--expand-monthly-byday (base-event rrule range) + "Expand a monthly nth-weekday (BYDAY) recurring event. +BASE-EVENT is the event plist, RRULE is parsed rrule (carrying :byday and +optionally :bysetpos), RANGE is date range. Steps month by month from +DTSTART's month, landing each occurrence on the day its BYDAY rule selects +-- never on DTSTART's day-of-month." + (let* ((start (plist-get base-event :start)) + (interval (plist-get rrule :interval)) + (byday (plist-get rrule :byday)) + (bysetpos (plist-get rrule :bysetpos)) + (until (plist-get rrule :until)) + (count (plist-get rrule :count)) + (occurrences '()) + (month-anchor (list (nth 0 start) (nth 1 start) 1)) + (start-day (nth 2 start)) + (first-month t) + (num-generated 0) + (range-end-time (cadr range)) + (max-iterations 1000) + (iterations 0)) + (when (<= interval 0) + (error "Invalid RRULE interval: %s (must be > 0)" interval)) + (while (and (< iterations max-iterations) + (or count until + (time-less-p (calendar-sync--date-to-time month-anchor) range-end-time)) + (or (not count) (< num-generated count)) + ;; A month starting after UNTIL can't contain an occurrence + ;; on-or-before it (UNTIL is inclusive, RFC 5545 3.3.10). + (or (not until) (calendar-sync--date-on-or-before-p month-anchor until))) + (setq iterations (1+ iterations)) + (dolist (day (calendar-sync--byday-days-in-month + (nth 0 month-anchor) (nth 1 month-anchor) byday bysetpos)) + (let* ((occurrence-date (list (nth 0 month-anchor) (nth 1 month-anchor) day)) + (occurrence-datetime (append occurrence-date (nthcdr 3 start)))) + ;; The series starts at DTSTART: skip earlier days in the first month. + (unless (and first-month (< day start-day)) + (when (or (not until) (calendar-sync--date-on-or-before-p occurrence-date until)) + (when (or (not count) (< num-generated count)) + (setq num-generated (1+ num-generated)) + (when (calendar-sync--date-in-range-p occurrence-datetime range) + (push (calendar-sync--create-occurrence base-event occurrence-datetime) + occurrences))))))) + (setq first-month nil) + (setq month-anchor (calendar-sync--add-months month-anchor interval))) + (when (>= iterations max-iterations) + (calendar-sync--log-silently + "calendar-sync: WARNING: Hit max iterations (%d) expanding monthly BYDAY event" + max-iterations)) + (nreverse occurrences))) + (defun calendar-sync--expand-monthly (base-event rrule range) "Expand monthly recurring event. -BASE-EVENT is the event plist, RRULE is parsed rrule, RANGE is date range." - (calendar-sync--expand-simple-recurrence - base-event rrule range #'calendar-sync--add-months)) +BASE-EVENT is the event plist, RRULE is parsed rrule, RANGE is date range. +A rule with BYDAY (nth weekday, e.g. 2WE, -1TU, or SU with BYSETPOS) +expands via `calendar-sync--expand-monthly-byday'; a plain rule steps +DTSTART's day-of-month." + (if (plist-get rrule :byday) + (calendar-sync--expand-monthly-byday base-event rrule range) + (calendar-sync--expand-simple-recurrence + base-event rrule range #'calendar-sync--add-months))) + +(defun calendar-sync--expand-yearly-byday (base-event rrule range) + "Expand a yearly nth-weekday event (e.g. BYMONTH=3;BYDAY=2SU). +BASE-EVENT is the event plist, RRULE is parsed rrule, RANGE is date range. +Reuses the monthly BYDAY expander with a 12-month step, anchored on +:bymonth (falling back to DTSTART's month)." + (let* ((start (plist-get base-event :start)) + (month (or (plist-get rrule :bymonth) (nth 1 start))) + (sched-event (plist-put (copy-sequence base-event) :start + (append (list (nth 0 start) month (nth 2 start)) + (nthcdr 3 start)))) + (sched-rrule (plist-put (copy-sequence rrule) :interval + (* 12 (or (plist-get rrule :interval) 1))))) + (calendar-sync--expand-monthly-byday sched-event sched-rrule range))) (defun calendar-sync--expand-yearly (base-event rrule range) "Expand yearly recurring event. -BASE-EVENT is the event plist, RRULE is parsed rrule, RANGE is date range." - (calendar-sync--expand-simple-recurrence - base-event rrule range - (lambda (date interval) (calendar-sync--add-months date (* 12 interval))))) +BASE-EVENT is the event plist, RRULE is parsed rrule, RANGE is date range. +A rule with BYDAY (the DST clock-change shape, BYMONTH=n;BYDAY=nWD) +expands via `calendar-sync--expand-yearly-byday'; a plain rule repeats +DTSTART's calendar date." + (if (plist-get rrule :byday) + (calendar-sync--expand-yearly-byday base-event rrule range) + (calendar-sync--expand-simple-recurrence + base-event rrule range + (lambda (date interval) (calendar-sync--add-months date (* 12 interval)))))) (defun calendar-sync--expand-recurring-event (event-str range) "Expand recurring event EVENT-STR into individual occurrences within RANGE. |