How to sort habits by priority in the org-agenda view?

Question

How can I sort habits in the org-agenda first by priority, then schedule + deadline + consistency?

I tried to set the org-agenda-sorting-strategy to various configurations, but ultimately habits are always sorted first by schedule + deadline + consistency followed by priority, the opposite of what I want.

I strongly prefer to avoid modifying the org source code like this SO question does.

Answer 1

Thanks to some guidance by Nicolas Goaziou, I created a solution that sorts the way I want by taking advantage of the user-defined sorting strategy:

(defun hw-org-agenda-sort-habits (a b)
  "Sort habits first by user priority, then by schedule+deadline+consistency."
  (let ((ha (get-text-property 1 'org-habit-p a))
        (hb (get-text-property 1 'org-habit-p b)))
    (when (and ha hb)
      (let ((pa (org-get-priority a))
            (pb (org-get-priority b)))
        (cond ((> pa pb) +1)
              ((< pa pb) -1)
              ((= pa pb) (org-cmp-values a b 'priority)))))))
(setq org-agenda-cmp-user-defined 'hw-org-agenda-sort-habits
      org-agenda-sorting-strategy '((agenda time-up user-defined-down habit-down)
                                    (todo priority-down category-keep)
                                    (tags priority-down category-keep)
                                    (search category-keep)))

Not the most elegant solution, but it does the job.