Add a filter when generating today's agenda view

Question

what I want to achieve

Say a ++2d habit not accomplished yesterday, I don't want it shown in today's agenda view but shown in tomorrow's and 2 days after tomorrow's and so forth.

what I tried

(defun my/several-day-habit-and-not-due-today ()
  "only work for today's habit list"
  (interactive)
  (let ((time (my/floor-time-to-date (org-time-string-to-time (org-entry-get nil "SCHEDULED"))))
        (repeater (org-get-repeat)))
    (string-match "\\([.+]\\)?\\(\\+[0-9]+\\)\\([hdwmy]\\)" repeater)
    (let ((repeater-type (match-string 1 repeater))
          (day (string-to-number (match-string 2 repeater)))
          (what (match-string 3 repeater))
          (today (my/floor-time-to-date)))
      (when (and (equal what "d")
                 (< day 5))
        (while (time-less-p time today)
          (setq time (time-add time (* day 60 60 24))))
        (time-less-p today time)))))

(defun my/org-is-habit-p (&optional pom)
  "Is the task at POM or point a habit?"
  (and (string= "habit" (org-entry-get (or pom (point)) "STYLE" t))
       (not (my/several-day-habit-and-not-due-today)) ;will show in ordinary agenda
       ))

(advice-add 'org-is-habit-p :override 'my/org-is-habit-p)

This way filtered it out as a habit, but it will show as a normal entry in agnda view.

any idea how I can filter it out in today's agenda view?

Answer 1

I don't use org-habit so I can not provide a full answer, but it looks like you can use a org-agenda-before-sorting-filter-function function for this. Read its docstring to see how it works.

Then make up some predicate expression that checks if a line is one of your particular org-habits and replace it in the appropriate place in the following code block:

(defun org-agenda-yesterday-habit-filter (line)
  ;; (pp line)
  (if (and (= (print (time-to-days (org-time-from-absolute (org-find-text-property-in-string 'date line))))
              (print (org-today)))
           "replace this string with some predicate expression that returns t for your habit")
      nil
    line))

(setq org-agenda-before-sorting-filter-function 'org-agenda-yesterday-habit-filter)

You could uncomment the pp expression to look at the string object in the *Messages* buffer. Also, the if could be replaced by a unless but I leave it in this form here for clarity.