emacs-orgmode@gnu.org archives
 help / color / mirror / code / Atom feed
blob eee354f269026c7d99464a70f975fa8ee8cabbe0 36412 bytes (raw)
name: lisp/oc-basic.el 	 # note: path name is non-authoritative(*)

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
 
;;; oc-basic.el --- basic back-end for citations  -*- lexical-binding: t; -*-

;; Copyright (C) 2021-2023 Free Software Foundation, Inc.

;; Author: Nicolas Goaziou <mail@nicolasgoaziou.fr>

;; This file is part of GNU Emacs.

;; GNU Emacs is free software: you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation, either version 3 of the License, or
;; (at your option) any later version.

;; GNU Emacs is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;; GNU General Public License for more details.

;; You should have received a copy of the GNU General Public License
;; along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.

;;; Commentary:

;; The `basic' citation processor provides "activate", "follow", "export" and
;; "insert" capabilities.

;; "activate" capability re-uses default fontification, but provides additional
;; features on both correct and wrong keys according to the bibliography
;; defined in the document.

;; When the mouse is over a known key, it displays the corresponding
;; bibliography entry.  Any wrong key, however, is highlighted with `error'
;; face.  Moreover, moving the mouse onto it displays a list of suggested correct
;; keys, and pressing <mouse-1> on the faulty key will try to fix it according to
;; those suggestions.

;; On a citation key, "follow" capability moves point to the corresponding entry
;; in the current bibliography.  Elsewhere on the citation, it asks the user to
;; follow any of the keys cited there, with completion.

;; "export" capability supports the following citation styles:
;;
;;   - author (a), including caps (c) variant,
;;   - noauthor (na) including bare (b) variant,
;;   - text (t), including bare (b), caps (c), and bare-caps (bc) variants,
;;   - note (ft, including bare (b), caps (c), and bare-caps (bc) variants,
;;   - nocite (n)
;;   - numeric (nb),
;;   - default, including bare (b), caps (c), and bare-caps (bc) variants.
;;
;; It also supports the following styles for bibliography:
;;   - plain
;;   - numeric
;;   - author-year (default)

;; "insert" capability inserts or edits (with completion) citation style or
;; citation reference keys.  In an appropriate place, it offers to insert a new
;; citation.  With a prefix argument, it removes the one at point.

;; It supports bibliography files in BibTeX (".bibtex"), biblatex (".bib") and
;; JSON (".json") format.

;; Disclaimer: this citation processor is meant to be a proof of concept, and
;; possibly a fall-back mechanism when nothing else is available.  It is too
;; limited for any serious use case.

;;; Code:

(require 'org-macs)
(org-assert-version)

(require 'bibtex)
(require 'json)
(require 'map)
(require 'oc)
(require 'seq)

(declare-function org-open-at-point "org" (&optional arg))
(declare-function org-open-file "org" (path &optional in-emacs line search))

(declare-function org-element-interpret-data "org-element" (data))
(declare-function org-element-property "org-element" (property element))
(declare-function org-element-type "org-element" (element))

(declare-function org-export-data "org-export" (data info))
(declare-function org-export-derived-backend-p "org-export" (backend &rest backends))
(declare-function org-export-raw-string "org-export" (contents))

\f
;;; Customization
(defcustom org-cite-basic-sorting-field 'author
  "Field used to sort bibliography items as a symbol, or nil."
  :group 'org-cite
  :package-version '(Org . "9.5")
  :type 'symbol
  :safe #'symbolp)

(defcustom org-cite-basic-author-year-separator ", "
  "String used to separate cites in an author-year configuration."
  :group 'org-cite
  :package-version '(Org . "9.5")
  :type 'string
  :safe #'stringp)

(defcustom org-cite-basic-max-key-distance 2
  "Maximum (Levenshtein) distance between a wrong key and its suggestions."
  :group 'org-cite
  :package-version '(Org . "9.5")
  :type 'integer
  :safe #'integerp)

(defcustom org-cite-basic-author-column-end 25
  "Column where author field ends in completion table, as an integer."
  :group 'org-cite
  :package-version '(Org . "9.5")
  :type 'integer
  :safe #'integerp)

(defcustom org-cite-basic-column-separator "  "
  "Column separator in completion table, as a string."
  :group 'org-cite
  :package-version '(Org . "9.5")
  :type 'string
  :safe #'stringp)

(defcustom org-cite-basic-mouse-over-key-face 'highlight
  "Face used when mouse is over a citation key."
  :group 'org-cite
  :package-version '(Org . "9.5")
  :type 'face
  :safe #'facep)

\f
;;; Internal variables
(defvar org-cite-basic--bibliography-cache nil
  "Cache for parsed bibliography files.

This is an association list following the pattern:

  (FILE-ID . ENTRIES)

FILE-ID is a cons cell (FILE . HASH), with FILE being the absolute file name of
the bibliography file, and HASH a hash of its contents.

ENTRIES is a hash table with citation references as keys and fields alist as
values.")

(defvar org-cite-basic--completion-cache (make-hash-table :test #'equal)
  "Cache for key completion table.

This is an a hash-table.")

\f
;;; Internal functions
(defun org-cite-basic--parse-json ()
  "Parse JSON entries in the current buffer.
Return a hash table with citation references as keys and fields alist as values."
  (let ((entries (make-hash-table :test #'equal)))
    (let ((json-array-type 'list)
          (json-key-type 'symbol))
      (dolist (item (json-read))
        (puthash (cdr (assq 'id item))
                 (mapcar (pcase-lambda (`(,field . ,value))
                           (pcase field
                             ((or 'author 'editors)
                              ;; Author and editors are arrays of
                              ;; objects, each of them designing a
                              ;; person.  These objects may contain
                              ;; multiple properties, but for this
                              ;; basic processor, we'll focus on
                              ;; `given' and `family'.
                              ;;
                              ;; For compatibility with BibTeX, add
                              ;; "and" between authors and editors.
                              (cons field
                                    (mapconcat
                                     (lambda (alist)
                                       (concat (alist-get 'family alist)
                                               " "
                                               (alist-get 'given alist)))
                                     value
                                     " and ")))
                             ('issued
                              ;; Date are expressed as an array
                              ;; (`date-parts') or a "string (`raw'
                              ;; or `literal'). In both cases,
                              ;; extract the year and associate it
                              ;; to `year' field, for compatibility
                              ;; with BibTeX format.
                              (let ((date (or (alist-get 'date-parts value)
                                              (alist-get 'literal value)
                                              (alist-get 'raw value))))
                                (cons 'year
                                      (cond
                                       ((consp date)
                                         (let ((year (caar date)))
                                           (cond
                                             ((numberp year) (number-to-string year))
                                             ((stringp year) year)
                                             (t
                                               (error
                                                 "First element of CSL-JSON date-parts should be a number or string, got %s: %S"
                                                 (type-of year) year)))))
                                       ((stringp date)
                                        (replace-regexp-in-string
                                          (rx
                                            (minimal-match (zero-or-more anything))
                                            (group-n 1 (repeat 4 digit))
                                            (zero-or-more anything))
                                          (rx (backref 1))
                                          date))
                                       (t
                                        (error "Unknown CSL-JSON date format: %S"
                                               value))))))
                             (_
                              (cons field value))))
                         item)
                 entries))
      entries)))

(defun org-cite-basic--parse-bibtex (dialect)
  "Parse BibTeX entries in the current buffer.
DIALECT is the BibTeX dialect used.  See `bibtex-dialect'.
Return a hash table with citation references as keys and fields alist as values."
  (let ((entries (make-hash-table :test #'equal))
        (bibtex-sort-ignore-string-entries t))
    (bibtex-set-dialect dialect t)
    ;; Throw an error if bibliography is malformed.
    (unless (bibtex-validate)
      (user-error "Malformed bibliography at %S"
                  (or (buffer-file-name) (current-buffer))))
    (bibtex-map-entries
     (lambda (key &rest _)
       ;; Normalize entries: field names are turned into symbols
       ;; including special "=key=" and "=type=", and consecutive
       ;; white spaces are removed from values.
       (puthash key
                (mapcar
                 (pcase-lambda (`(,field . ,value))
                   (pcase field
                     ("=key=" (cons 'id key))
                     ("=type=" (cons 'type value))
                     (_
                      (cons
                       (intern (downcase field))
                       (replace-regexp-in-string "[ \t\n]+" " " value)))))
                 ;; Parse, substituting the @string replacements.
                 ;; See Emacs bug#56475 discussion.
                 (let ((bibtex-string-files `(,(buffer-file-name)))
                       (bibtex-expand-strings t))
                   (bibtex-parse-entry t)))
                entries)))
    entries))

(defvar org-cite-basic--file-id-cache nil
  "Hash table linking files to their hash.")
(defun org-cite-basic--parse-bibliography (&optional info)
  "List all entries available in the buffer.

Each association follows the pattern

  (FILE . ENTRIES)

where FILE is the absolute file name of the BibTeX file, and ENTRIES is a hash
table where keys are references and values are association lists between fields,
as symbols, and values as strings or nil.

Optional argument INFO is the export state, as a property list."
  (unless (hash-table-p org-cite-basic--file-id-cache)
    (setq org-cite-basic--file-id-cache (make-hash-table :test #'equal)))
  (if (plist-member info :cite-basic/bibliography)
      (plist-get info :cite-basic/bibliography)
    (let ((results nil))
      (dolist (file (org-cite-list-bibliography-files))
        (when (file-readable-p file)
          (with-temp-buffer
            (when (or (file-has-changed-p file)
                      (not (gethash file org-cite-basic--file-id-cache)))
              (insert-file-contents file)
              (set-visited-file-name file t)
              (puthash file (buffer-hash) org-cite-basic--file-id-cache))
            (condition-case nil
                (unwind-protect
	            (let* ((file-id (cons file (gethash file org-cite-basic--file-id-cache)))
                           (entries
                            (or (cdr (assoc file-id org-cite-basic--bibliography-cache))
                                (let ((table
                                       (pcase (file-name-extension file)
                                         ("json" (org-cite-basic--parse-json))
                                         ("bib" (org-cite-basic--parse-bibtex 'biblatex))
                                         ("bibtex" (org-cite-basic--parse-bibtex 'BibTeX))
                                         (ext
                                          (user-error "Unknown bibliography extension: %S"
                                                      ext)))))
                                  (push (cons file-id table) org-cite-basic--bibliography-cache)
                                  table))))
                      (push (cons file entries) results))
                  (set-visited-file-name nil t))
              (error (setq org-cite-basic--file-id-cache nil))))))
      (when info (plist-put info :cite-basic/bibliography results))
      results)))

(defun org-cite-basic--key-number (key info)
  "Return number associated to cited KEY.
INFO is the export state, as a property list."
  (let ((predicate
         (org-cite-basic--field-less-p org-cite-basic-sorting-field info)))
    (org-cite-key-number key info predicate)))

(defun org-cite-basic--all-keys ()
  "List all keys available in current bibliography."
  (seq-mapcat (pcase-lambda (`(,_ . ,entries))
                (map-keys entries))
              (org-cite-basic--parse-bibliography)))

(defun org-cite-basic--get-entry (key &optional info)
  "Return BibTeX entry for KEY, as an association list.
When non-nil, INFO is the export state, as a property list."
  (catch :found
    (pcase-dolist (`(,_ . ,entries) (org-cite-basic--parse-bibliography info))
      (let ((entry (gethash key entries)))
        (when entry (throw :found entry))))
    nil))

(defun org-cite-basic--get-field (field entry-or-key &optional info raw)
  "Return FIELD value for ENTRY-OR-KEY, or nil.

FIELD is a symbol.  ENTRY-OR-KEY is either an association list, as returned by
`org-cite-basic--get-entry', or a string representing a citation key.

Optional argument INFO is the export state, as a property list.

Return value may be nil or a string.  If current export back-end is derived
from `latex', return a raw string instead, unless optional argument RAW is
non-nil.

Throw an error if the field value is non-string and non-nil."
  (let ((value
         (cdr
          (assq field
                (pcase entry-or-key
                  ((pred stringp)
                   (org-cite-basic--get-entry entry-or-key info))
                  ((pred consp)
                   entry-or-key)
                  (_
                   (error "Wrong value for ENTRY-OR-KEY: %S" entry-or-key)))))))
    (when (and value (not (stringp value)))
      (error "Non-string bibliography field value: %S" value))
    (if (and value
             (not raw)
             (org-export-derived-backend-p (plist-get info :back-end) 'latex))
        (org-export-raw-string value)
      value)))

(defun org-cite-basic--shorten-names (names)
  "Return a list of family names from a list of full NAMES.

To better accomomodate corporate names, this will only shorten
personal names of the form \"family, given\"."
  (when (stringp names)
    (mapconcat
     (lambda (name)
       (if (eq 1 (length name))
           (cdr (split-string name))
         (car (split-string name ", "))))
     (split-string names " and ")
     ", ")))

(defun org-cite-basic--number-to-suffix (n)
  "Compute suffix associated to number N.
This is used for disambiguation."
  (let ((result nil))
    (apply #'string
           (mapcar (lambda (n) (+ 97 n))
                   (catch :complete
                     (while t
                       (push (% n 26) result)
                       (setq n (/ n 26))
                       (cond
                        ((= n 0) (throw :complete result))
                        ((< n 27) (throw :complete (cons (1- n) result)))
                        ((= n 27) (throw :complete (cons 0 (cons 0 result))))
                        (t nil))))))))

(defun org-cite-basic--get-author (entry-or-key &optional info raw)
  "Return author associated to ENTRY-OR-KEY.

ENTRY-OR-KEY, INFO and RAW arguments are the same arguments as
used in `org-cite-basic--get-field', which see.

Author is obtained from the \"author\" field, if available, or
from the \"editor\" field otherwise."
  (or (org-cite-basic--get-field 'author entry-or-key info raw)
      (org-cite-basic--get-field 'editor entry-or-key info raw)))

(defun org-cite-basic--get-year (entry-or-key info &optional no-suffix)
  "Return year associated to ENTRY-OR-KEY.

ENTRY-OR-KEY is either an association list, as returned by
`org-cite-basic--get-entry', or a string representing a citation
key.  INFO is the export state, as a property list.

Year is obtained from the \"year\" field, if available, or from
the \"date\" field if it starts with a year pattern.

Unlike `org-cite-basic--get-field', this function disambiguates
author-year patterns by adding a letter suffix to the year when
necessary, unless optional argument NO-SUFFIX is non-nil."
  ;; The cache is an association list with the following structure:
  ;;
  ;;    (AUTHOR-YEAR . KEY-SUFFIX-ALIST).
  ;;
  ;; AUTHOR-YEAR is the author year pair associated to current entry
  ;; or key.
  ;;
  ;; KEY-SUFFIX-ALIST is an association (KEY . SUFFIX), where KEY is
  ;; the cite key, as a string, and SUFFIX is the generated suffix
  ;; string, or the empty string.
  (let* ((author (org-cite-basic--get-author entry-or-key info 'raw))
         (year
          (or (org-cite-basic--get-field 'year entry-or-key info 'raw)
              (let ((date
                     (org-cite-basic--get-field 'date entry-or-key info t)))
                (and (stringp date)
                     (string-match (rx string-start
                                       (group (= 4 digit))
                                       (or string-end (not digit)))
                                   date)
                     (match-string 1 date)))))
         (cache-key (cons author year))
         (key
          (pcase entry-or-key
            ((pred stringp) entry-or-key)
            ((pred consp) (cdr (assq 'id entry-or-key)))
            (_ (error "Wrong value for ENTRY-OR-KEY: %S" entry-or-key))))
         (cache (plist-get info :cite-basic/author-date-cache)))
    (pcase (assoc cache-key cache)
      ('nil
       (let ((value (cons cache-key (list (cons key "")))))
         (plist-put info :cite-basic/author-date-cache (cons value cache))
         year))
      (`(,_ . ,alist)
       (let ((suffix
              (or (cdr (assoc key alist))
                  (let ((new (org-cite-basic--number-to-suffix
                              (1- (length alist)))))
                    (push (cons key new) alist)
                    new))))
         (if no-suffix year (concat year suffix)))))))

(defun org-cite-basic--print-entry (entry style &optional info)
  "Format ENTRY according to STYLE string.
ENTRY is an alist, as returned by `org-cite-basic--get-entry'.
Optional argument INFO is the export state, as a property list."
  (let ((author (org-cite-basic--get-author entry info))
        (title (org-cite-basic--get-field 'title entry info))
        (from
         (or (org-cite-basic--get-field 'publisher entry info)
             (org-cite-basic--get-field 'journal entry info)
             (org-cite-basic--get-field 'institution entry info)
             (org-cite-basic--get-field 'school entry info))))
    (pcase style
      ("plain"
       (let ((year (org-cite-basic--get-year entry info 'no-suffix)))
         (org-cite-concat
          (org-cite-basic--shorten-names author) ". "
          title (and from (list ", " from)) ", " year ".")))
      ("numeric"
       (let ((n (org-cite-basic--key-number (cdr (assq 'id entry)) info))
             (year (org-cite-basic--get-year entry info 'no-suffix)))
         (org-cite-concat
          (format "[%d] " n) author ", "
          (org-cite-emphasize 'italic title)
          (and from (list ", " from)) ", "
          year ".")))
      ;; Default to author-year.  Use year disambiguation there.
      (_
       (let ((year (org-cite-basic--get-year entry info)))
         (org-cite-concat
          author " (" year "). "
          (org-cite-emphasize 'italic title)
          (and from (list ", " from)) "."))))))

\f
;;; "Activate" capability
(defun org-cite-basic--close-keys (key keys)
  "List cite keys close to KEY in terms of string distance."
  (seq-filter (lambda (k)
                (>= org-cite-basic-max-key-distance
                    (org-string-distance k key)))
              keys))

(defun org-cite-basic--set-keymap (beg end suggestions)
  "Set keymap on citation key between BEG and END positions.

When the key is know, SUGGESTIONS is nil.  Otherwise, it may be
a list of replacement keys, as strings, which will be offered as
substitutes for the unknown key.  Finally, it may be the symbol
`all'."
  (let ((km (make-sparse-keymap)))
    (define-key km (kbd "<mouse-1>")
      (pcase suggestions
        ('nil #'org-open-at-point)
        ('all #'org-cite-insert)
        (_
         (lambda ()
           (interactive)
           (save-excursion
             (goto-char beg)
             (delete-region beg end)
             (insert
              "@"
              (if (= 1 (length suggestions))
                  (car suggestions)
                (completing-read "Did you mean: "
                                 suggestions nil t))))))))
    (put-text-property beg end 'keymap km)))

(defun org-cite-basic-activate (citation)
  "Set various text properties on CITATION object.

Fontify whole citation with `org-cite' face.  Fontify key with `error' face
when it does not belong to known keys.  Otherwise, use `org-cite-key' face.

Moreover, when mouse is on a known key, display the corresponding bibliography.
On a wrong key, suggest a list of possible keys, and offer to substitute one of
them with a mouse click."
  (pcase-let ((`(,beg . ,end) (org-cite-boundaries citation))
              (keys (org-cite-basic--all-keys)))
    (put-text-property beg end 'font-lock-multiline t)
    (add-face-text-property beg end 'org-cite)
    (dolist (reference (org-cite-get-references citation))
      (pcase-let* ((`(,beg . ,end) (org-cite-key-boundaries reference))
                   (key (org-element-property :key reference)))
        ;; Highlight key on mouse over.
        (put-text-property beg end
                           'mouse-face
                           org-cite-basic-mouse-over-key-face)
        (if (member key keys)
            ;; Activate a correct key.  Face is `org-cite-key' and
            ;; `help-echo' displays bibliography entry, for reference.
            ;; <mouse-1> calls `org-open-at-point'.
            (let* ((entry (org-cite-basic--get-entry key))
                   (bibliography-entry
                    (org-element-interpret-data
                     (org-cite-basic--print-entry entry "plain"))))
              (add-face-text-property beg end 'org-cite-key)
              (put-text-property beg end 'help-echo bibliography-entry)
              (org-cite-basic--set-keymap beg end nil))
          ;; Activate a wrong key.  Face is `error', `help-echo'
          ;; displays possible suggestions.
          (add-face-text-property beg end 'error)
          (let ((close-keys (org-cite-basic--close-keys key keys)))
            (when close-keys
              (put-text-property beg end 'help-echo
                                 (concat "Suggestions (mouse-1 to substitute): "
                                         (mapconcat #'identity close-keys " "))))
            ;; When the are close know keys, <mouse-1> provides
            ;; completion to fix the current one.  Otherwise, call
            ;; `org-cite-insert'.
            (org-cite-basic--set-keymap beg end (or close-keys 'all))))))))

\f
;;; "Export" capability
(defun org-cite-basic--format-author-year (citation format-cite format-ref info)
  "Format CITATION object according to author-year format.

FORMAT-CITE is a function of three arguments: the global prefix, the contents,
and the global suffix.  All arguments can be strings or secondary strings.

FORMAT-REF is a function of four arguments: the reference prefix, as a string or
secondary string, the author, the year, and the reference suffix, as a string or
secondary string.

INFO is the export state, as a property list."
  (org-export-data
   (funcall format-cite
            (org-element-property :prefix citation)
            (org-cite-mapconcat
             (lambda (ref)
               (let ((k (org-element-property :key ref))
                     (prefix (org-element-property :prefix ref))
                     (suffix (org-element-property :suffix ref)))
                 (funcall format-ref
                          prefix
                          (or (org-cite-basic--get-author k info) "??")
                          (or (org-cite-basic--get-year k info) "????")
                          suffix)))
             (org-cite-get-references citation)
             org-cite-basic-author-year-separator)
            (org-element-property :suffix citation))
   info))

(defun org-cite-basic--citation-numbers (citation info)
  "Return numbers associated to references in CITATION object.
INFO is the export state as a property list."
  (let* ((numbers
          (sort (mapcar (lambda (k) (org-cite-basic--key-number k info))
                        (org-cite-get-references citation t))
                #'<))
         (last (car numbers))
         (result (list (number-to-string (pop numbers)))))
    ;; Use compact number references, i.e., "1, 2, 3" becomes "1-3".
    (while numbers
      (let ((current (pop numbers))
            (next (car numbers)))
        (cond
         ((and next
               (= current (1+ last))
               (= current (1- next)))
          (unless (equal "-" (car result))
            (push "-" result)))
         ((equal "-" (car result))
          (push (number-to-string current) result))
         (t
          (push (format ", %d" current) result)))
        (setq last current)))
    (apply #'concat (nreverse result))))

(defun org-cite-basic--field-less-p (field info)
  "Return a sort predicate comparing FIELD values for two citation keys.
INFO is the export state, as a property list."
  (and field
       (lambda (a b)
         (string-collate-lessp
          (org-cite-basic--get-field field a info 'raw)
          (org-cite-basic--get-field field b info 'raw)
          nil t))))

(defun org-cite-basic--sort-keys (keys info)
  "Sort KEYS by author name.
INFO is the export communication channel, as a property list."
  (let ((predicate (org-cite-basic--field-less-p org-cite-basic-sorting-field info)))
    (if predicate
        (sort keys predicate)
      keys)))

(defun org-cite-basic-export-citation (citation style _ info)
  "Export CITATION object.
STYLE is the expected citation style, as a pair of strings or nil.  INFO is the
export communication channel, as a property list."
  (let ((has-variant-p
         (lambda (variant type)
           ;; Non-nil when style VARIANT has TYPE.  TYPE is either
           ;; `bare' or `caps'.
           (member variant
                   (pcase type
                     ('bare '("bare" "bare-caps" "b" "bc"))
                     ('caps '("caps" "bare-caps" "c" "bc"))
                     (_ (error "Invalid variant type: %S" type)))))))
    (pcase style
      ;; "author" style.
      (`(,(or "author" "a") . ,variant)
       (let ((caps (member variant '("caps" "c"))))
         (org-export-data
          (mapconcat
           (lambda (key)
             (or
              (let ((author (org-cite-basic--get-author key info)))
                (if caps (capitalize author) author))
              "??"))
           (org-cite-get-references citation t)
           org-cite-basic-author-year-separator)
          info)))
      ;; "noauthor" style.
      (`(,(or "noauthor" "na") . ,variant)
       (format (if (funcall has-variant-p variant 'bare) "%s" "(%s)")
               (mapconcat (lambda (key) (or (org-cite-basic--get-year key info) "????"))
                          (org-cite-get-references citation t)
                          org-cite-basic-author-year-separator)))
      ;; "nocite" style.
      (`(,(or "nocite" "n") . ,_) nil)
      ;; "text" and "note" styles.
      (`(,(and (or "text" "note" "t" "ft") style) . ,variant)
       (when (and (member style '("note" "ft"))
                  (not (org-cite-inside-footnote-p citation)))
         (org-cite-adjust-note citation info)
         (org-cite-wrap-citation citation info))
       (let ((bare (funcall has-variant-p variant 'bare))
             (caps (funcall has-variant-p variant 'caps)))
         (org-cite-basic--format-author-year
          citation
          (lambda (p c s) (org-cite-concat p c s))
          (lambda (p a y s)
            (org-cite-concat p
                             (if caps (capitalize a) a)
                             (if bare " " " (")
                             y s
                             (and (not bare) ")")))
          info)))
      ;; "numeric" style.
      ;;
      ;; When using this style on citations with multiple references,
      ;; use global affixes and ignore local ones.
      (`(,(or "numeric" "nb") . ,_)
       (pcase-let ((`(,prefix . ,suffix) (org-cite-main-affixes citation)))
         (org-export-data
          (org-cite-concat
           "(" prefix (org-cite-basic--citation-numbers citation info) suffix ")")
          info)))
      ;; Default ("nil") style.
      (`(,_ . ,variant)
       (let ((bare (funcall has-variant-p variant 'bare))
             (caps (funcall has-variant-p variant 'caps)))
         (org-cite-basic--format-author-year
          citation
          (lambda (p c s)
            (org-cite-concat (and (not bare) "(") p c s (and (not bare) ")")))
          (lambda (p a y s)
            (org-cite-concat p (if caps (capitalize a) a) ", " y s))
          info)))
      ;; This should not happen.
      (_ (error "Invalid style: %S" style)))))

(defun org-cite-basic-export-bibliography (keys _files style _props backend info)
  "Generate bibliography.
KEYS is the list of cited keys, as strings.  STYLE is the expected bibliography
style, as a string.  BACKEND is the export back-end, as a symbol.  INFO is the
export state, as a property list."
  (mapconcat
   (lambda (entry)
     (org-export-data
      (org-cite-make-paragraph
       (and (org-export-derived-backend-p backend 'latex)
            (org-export-raw-string "\\noindent\n"))
       (org-cite-basic--print-entry entry style info))
      info))
   (delq nil
         (mapcar
          (lambda (k) (org-cite-basic--get-entry k info))
          (org-cite-basic--sort-keys keys info)))
   "\n"))

\f
;;; "Follow" capability
(defun org-cite-basic-goto (datum _)
  "Follow citation or citation reference DATUM.
When DATUM is a citation reference, open bibliography entry referencing
the citation key.  Otherwise, select which key to follow among all keys
present in the citation."
  (let* ((key
          (if (eq 'citation-reference (org-element-type datum))
              (org-element-property :key datum)
            (pcase (org-cite-get-references datum t)
              (`(,key) key)
              (keys
               (or (completing-read "Select citation key: " keys nil t)
                   (user-error "Aborted"))))))
         (file
          (pcase (seq-find (pcase-lambda (`(,_ . ,entries))
                             (gethash key entries))
                           (org-cite-basic--parse-bibliography))
            (`(,f . ,_) f)
            (_  (user-error "Cannot find citation key: %S" key)))))
    (org-open-file file '(4))
    (pcase (file-name-extension file)
      ("json"
       ;; `rx' can not be used with Emacs <27.1 since `literal' form
       ;; is not supported.
       (let ((regexp (rx-to-string `(seq "\"id\":" (0+ (any "[ \t]")) "\"" ,key "\"") t)))
         (goto-char (point-min))
         (re-search-forward regexp)
         (search-backward "{")))
      (_
       (bibtex-set-dialect)
       (bibtex-search-entry key)))))

\f
;;; "Insert" capability
(defun org-cite-basic--complete-style (_)
  "Offer completion for style.
Return chosen style as a string."
  (let* ((styles
          (mapcar (pcase-lambda (`((,style . ,_) . ,_))
                    style)
                  (org-cite-supported-styles))))
    (pcase styles
      (`(,style) style)
      (_ (completing-read "Style (\"\" for default): " styles nil t)))))

(defun org-cite-basic--key-completion-table ()
  "Return completion table for cite keys, as a hash table.

In this hash table, keys are a strings with author, date, and
title of the reference.  Values are the cite keys.

Return nil if there are no bibliography files or no entries."
  ;; Populate bibliography cache.
  (let ((entries (org-cite-basic--parse-bibliography)))
    (cond
     ((null entries) nil)               ;no bibliography files
     ((gethash entries org-cite-basic--completion-cache)
      org-cite-basic--completion-cache)
     (t
      (clrhash org-cite-basic--completion-cache)
      (dolist (key (org-cite-basic--all-keys))
        (let* ((entry (org-cite-basic--get-entry
                       key
                       ;; Supply pre-calculated bibliography to avoid
                       ;; performance degradation.
                       (list :cite-basic/bibliography entries)))
               (completion
                (concat
                 (let ((author (org-cite-basic--get-author entry nil 'raw)))
                   (if author
                       (truncate-string-to-width
                        (replace-regexp-in-string " and " "; " author)
                        org-cite-basic-author-column-end nil ?\s)
                     (make-string org-cite-basic-author-column-end ?\s)))
                 org-cite-basic-column-separator
                 (let ((date (org-cite-basic--get-year entry nil 'no-suffix)))
                   (format "%4s" (or date "")))
                 org-cite-basic-column-separator
                 (org-cite-basic--get-field 'title entry nil t))))
          (puthash completion key org-cite-basic--completion-cache)))
      (unless (map-empty-p org-cite-basic--completion-cache) ;no key
        (puthash entries t org-cite-basic--completion-cache)
        org-cite-basic--completion-cache)))))

(defun org-cite-basic--complete-key (&optional multiple)
  "Prompt for a reference key and return a citation reference string.

When optional argument MULTIPLE is non-nil, prompt for multiple
keys, until one of them is nil.  Then return the list of
reference strings selected.

Raise an error when no bibliography is set in the buffer."
  (let* ((table
          (or (org-cite-basic--key-completion-table)
              (user-error "No bibliography set")))
         (prompt
          (lambda (text)
            (completing-read text table nil t))))
    (if (null multiple)
        (let ((key (gethash (funcall prompt "Key: ") table)))
          (org-string-nw-p key))
      (let* ((keys nil)
             (build-prompt
              (lambda ()
                (if keys
                    (format "Key (empty input exits) %s: "
                            (mapconcat #'identity (reverse keys) ";"))
                  "Key (empty input exits): "))))
        (let ((key (funcall prompt (funcall build-prompt))))
          (while (org-string-nw-p key)
            (push (gethash key table) keys)
            (setq key (funcall prompt (funcall build-prompt)))))
        keys))))

\f
;;; Register processor
(org-cite-register-processor 'basic
  :activate #'org-cite-basic-activate
  :export-citation #'org-cite-basic-export-citation
  :export-bibliography #'org-cite-basic-export-bibliography
  :follow #'org-cite-basic-goto
  :insert (org-cite-make-insert-processor #'org-cite-basic--complete-key
                                          #'org-cite-basic--complete-style)
  :cite-styles
  '((("author" "a") ("caps" "c"))
    (("noauthor" "na") ("bare" "b"))
    (("nocite" "n"))
    (("note" "ft") ("bare-caps" "bc") ("caps" "c"))
    (("numeric" "nb"))
    (("text" "t") ("bare-caps" "bc") ("caps" "c"))
    (("nil") ("bare" "b") ("bare-caps" "bc") ("caps" "c"))))

(provide 'oc-basic)
;;; oc-basic.el ends here

debug log:

solving eee354f26 ...
found eee354f26 in https://list.orgmode.org/orgmode/87r0t3gahd.fsf@localhost/
found 12b627e71 in https://git.savannah.gnu.org/cgit/emacs/org-mode.git
preparing index
index prepared:
100644 12b627e71c5611b25debef05d7ad4da7f5df312c	lisp/oc-basic.el

applying [1/1] https://list.orgmode.org/orgmode/87r0t3gahd.fsf@localhost/
diff --git a/lisp/oc-basic.el b/lisp/oc-basic.el
index 12b627e71..eee354f26 100644

Checking patch lisp/oc-basic.el...
Applied patch lisp/oc-basic.el cleanly.

index at:
100644 eee354f269026c7d99464a70f975fa8ee8cabbe0	lisp/oc-basic.el

(*) Git path names are given by the tree(s) the blob belongs to.
    Blobs themselves have no identifier aside from the hash of its contents.^

Code repositories for project(s) associated with this public inbox

	https://git.savannah.gnu.org/cgit/emacs/org-mode.git

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).