I've been struggling with this for a while, and am a mediocre programmer, so thought I'd ask for help here.
I started out writing this generate capf to insert citation keys, but have decided to make it specific to org-cite.
Here's the commented function.
TIA.
Note the "candidates" variable accesses a cached alist, of the form:
("long search string with title, author, etc." . "citekey")
So I want the user to be able to select on the car, but insert the cdr.
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(defun bibtex-actions-complete-key-at-point-oc ()
"Complete org-cite citation key at point.
When inserting '@' in a buffer the capf UI will present user with
a list of entries, from which they can narrow against a string
which includes title, author, etc., and then select one. This
function will then return the key 'key', resulting in '@key' at
point."
;; FIX exit-function is wrong; results in "no match"
;; TODO tighten this regex for org-cite
(when (looking-back "@[a-zA-Z]+" 5)
(let* ((candidates (bibtex-actions--get-candidates))
(begin (save-excursion (backward-word) (point)))
(end (point)))
(list begin end candidates :exclusive 'no
:exit-function
(lambda (chosen status)
(when (eq status 'finished)
(cdr (assoc chosen candidates))))))))
--8<---------------cut here---------------end--------------->8---