summaryrefslogtreecommitdiff
path: root/gnosis.el
blob: abda991e010c8a4cdbda9b9d275bd34afc7cccd2 (about) (plain)
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
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
;;; gnosis.el --- Spaced Repetition Learning Tool  -*- lexical-binding: t; -*-

;; Copyright (C) 2023  Thanos Apollo

;; Author: Thanos Apollo <[email protected]>
;; Keywords: extensions
;; URL: https://git.thanosapollo.org/gnosis
;; Version: 0.0.1

;; Package-Requires: ((emacs "27.2") (compat "29.1.4.2") (emacsql "20230228"))

;; This program 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.

;; This program 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 this program.  If not, see <https://www.gnu.org/licenses/>.

;;; Commentary:

;; Work in progress

;;; Code:


(require 'emacsql)
(require 'emacsql-sqlite)
(require 'cl-lib)

(require 'gnosis-algorithm)

(defgroup gnosis nil
  "Spaced repetition learning tool."
  :group 'external
  :prefix "gnosis-")

(defcustom gnosis-dir (concat user-emacs-directory "gnosis")
  "Gnosis directory."
  :type 'directory
  :group 'gnosis)

(defcustom gnosis-cloze-char "__"
  "Gnosis cloze character."
  :type 'string
  :group 'gnosis)


(defvar gnosis-images-dir (concat (file-name-as-directory gnosis-dir) "images")
  "Gnosis images directory.")

(defvar gnosis-db (emacsql-sqlite (concat (file-name-as-directory gnosis-dir) "gnosis.db"))
  "Gnosis database file.

WARNING: Do not change this value!")

(defvar gnosis-testing nil
  "When t, warn user he is in a testing environment.")

(defconst gnosis-db-version 1
  "Gnosis database version.")

;;; Faces

(defgroup gnosis-faces nil
  "Faces used by gnosis."
  :group 'gnosis
  :tag "Gnosis Faces"
  :prefix 'gnosis-face)

(defface gnosis-face-extra
  '((t :inherit markdown-italic-face))
  "Face for extra-notes from note."
  :group 'gnosis-faces)

(defface gnosis-face-main
  '((t :inherit default))
  "Face for main section from note."
  :group 'gnosis-face-faces)

(defface gnosis-face-seperator
  '((t :inherit warning))
  "Face for section seperator."
  :group 'gnosis-face)

(defface gnosis-face-directions
  '((t :inherit underline))
  "Face for gnosis directions."
  :group 'gnosis-face)

(defface gnosis-face-correct
  '((t :inherit match))
  "Face for user choice."
  :group 'gnosis-face)

(defface gnosis-face-cloze
  '((t :inherit cursor))
  "Face for clozes."
  :group 'gnosis-face)

(defface gnosis-face-false
  '((t :inherit error))
  "Face for user choice."
  :group 'gnosis-face)

(defface gnosis-face-hint
  '((t :inherit warning))
  "Face for user choice."
  :group 'gnosis-face)

(defface gnosis-face-cloze-unanswered
  '((t :inherit underline))
  "Face for user choice."
  :group 'gnosis-face)



(cl-defun gnosis-select (value table &optional (restrictions '1=1))
  "Select VALUE from TABLE, optionally with RESTRICTIONS."
  (gnosis-db-init)
  (emacsql gnosis-db `[:select ,value :from ,table :where ,restrictions]))

(cl-defun gnosis--create-table (table &optional values)
  "Create TABLE for VALUES."
  (emacsql gnosis-db `[:create-table ,table ,values]))

(cl-defun gnosis--drop-table (table)
  "Drop TABLE from gnosis-db."
  (emacsql gnosis-db `[:drop-table ,table]))

(cl-defun gnosis--insert-into (table values)
  "Insert VALUES to TABLE."
  (gnosis-db-init)
  (emacsql gnosis-db `[:insert :into ,table :values ,values]))

(cl-defun gnosis-update (table value where)
  "Update records in TABLE with to new VALUE based on the given WHERE condition.

Example:
 (gnosis-update ='notes ='(= main \"NEW VALUE\") ='(= id 12))"
  (emacsql gnosis-db `[:update ,table :set ,value :where ,where]))

(cl-defun gnosis-get (value table &optional (restrictions '1=1))
  "Return VALUE from TABLE, optionally with where RESTRICTIONS."
  (caar (gnosis-select value table restrictions)))

(defun gnosis-get-note-tags (id)
  "Return tags for note ID."
  (gnosis-get 'tags 'notes `(= id ,id)))

(defun gnosis--delete (table value)
  "From TABLE use where to delete VALUE."
  (emacsql gnosis-db `[:delete :from ,table :where ,value]))

(defmacro with-gnosis-buffer (&rest body)
  "Execute BODY in gnosis buffer."
  `(with-current-buffer (switch-to-buffer (get-buffer-create "*gnosis*"))
     (gnosis-mode)
     ,@body))

(cl-defun gnosis-completing-read (prompt options info &optional (face-for-info 'font-lock-doc-face))
  "A version of `completing-read' with text properties, padding & choosable face.
Returns selected option from OPTIONS.

WARNING: Do NOT use htis functions as is now!

PROMPT is a string to prompt with; normally it ends in a colon and a space.
OPTIONS is a list of strings.
INFO is a list of strings, which will be displayed as additional info for option
FACE-FOR-INFO is the face used to display info for option."
  (let* ((choices (cl-mapcar 'cons options info))
         (max-choice-length (apply 'max (mapcar 'length options)))
         (formatted-choices
          (mapcar (lambda (choice)
                    (cons (concat (format "%s" (car choice))
                                  (make-string (- max-choice-length (length (car choice))) ? )
                                  "      "
                                  (propertize (format "%s" (cdr choice)) 'face face-for-info))
                          (car choice)))
                  choices)))
    (cdr (assoc (completing-read prompt formatted-choices nil t)
		formatted-choices))))

(defun gnosis-replace-item-at-index (index new-item list)
  "Replace item at INDEX in LIST with NEW-ITEM."
  (cl-loop for i from 0 for item in list
           if (= i index) collect new-item
           else collect item))

(defun gnosis-display--question (id)
  "Display main row for note ID."
  (let ((question (gnosis-get 'main 'notes `(= id ,id))))
    (with-gnosis-buffer
     (erase-buffer)
     (fill-paragraph (insert (concat "\n"
				     (propertize question 'face 'gnosis-face-main)))))))

(defun gnosis-display--cloze-sentence (sentence clozes)
  "Display cloze sentence for SENTENCE with CLOZES."
  (with-gnosis-buffer
   (erase-buffer)
   (fill-paragraph
    (insert
     (concat "\n"
	     (gnosis-cloze-replace-words sentence clozes (propertize gnosis-cloze-char 'face 'gnosis-face-cloze)))))))

(defun gnosis-display--basic-answer (answer success user-input)
  "Display ANSWER.

When SUCCESS nil, display USER-INPUT as well"
  (with-gnosis-buffer
   (insert
    (concat "\n\n"
	    (propertize "Answer:" 'face 'gnosis-face-directions)
	    " "
	    (propertize answer 'face 'gnosis-face-correct)))
   ;; Insert user wrong answer
   (when (not success)
     (insert (concat "\n"
		     (propertize "Your answer:" 'face 'gnosis-face-directions)
		     " "
		     (propertize user-input 'face 'gnosis-face-false))))))

(defun gnosis-display--hint (hint)
  "Display HINT."
  (with-gnosis-buffer
   (goto-char (point-max))
   (insert (concat
	    (propertize "\n\n-----\n" 'face 'gnosis-face-seperator)
	    (propertize hint 'face 'gnosis-face-hint)))))

(cl-defun gnosis-display-cloze-reveal (&key (cloze-char gnosis-cloze-char) replace (success t) (face nil))
  "Replace CLOZE-CHAR with REPLACE.

If FACE nil, propertize replace using `gnosis-face-correct', or
`gnosis-face-false' when (not SUCCESS). Else use FACE value."
  (with-gnosis-buffer
   (goto-char (point-min))
   (search-forward cloze-char nil t)
   (replace-match (propertize replace 'face (if (not face)
						(if success 'gnosis-face-correct 'gnosis-face-false)
					      face)))))

(cl-defun gnosis-display-cloze-user-answer (user-input &optional (false t))
  "Display USER-INPUT answer for cloze note upon failed review.

If FALSE t, use gnosis-face-false face"
  (with-gnosis-buffer
   (goto-char (point-max))
   (insert (concat "\n\n"
		   (propertize "Your answer:" 'face 'gnosis-face-directions)
		   " "
		   (propertize user-input 'face (if false 'gnosis-face-false 'gnosis-face-correct))))))

(defun gnosis-display--correct-answer-mcq (answer user-choice)
  "Display correct ANSWER & USER-CHOICE for MCQ note."
  (with-gnosis-buffer
   (insert (concat "\n\n"
		   (propertize "Correct Answer:" 'face 'gnosis-face-directions)
		   " "
		   (propertize answer 'face 'gnosis-face-correct)
		   "\n"
		   (propertize "Your answer:" 'face 'gnosis-face-directions)
		   " "
		   (propertize user-choice 'face (if (string= answer user-choice)
						     'gnosis-face-correct
						   'gnosis-face-false))))))

(defun gnosis-display--extra (id)
  "Display extra information for note ID."
  (let ((extras (gnosis-get 'extra-notes 'extras `(= id ,id))))
    (with-gnosis-buffer
     (goto-char (point-max))
     (insert (propertize "\n\n-----\n" 'face 'gnosis-face-seperator))
     (fill-paragraph (insert (concat "\n" (propertize extras 'face 'gnosis-face-extra)))))))

(defun gnosis-display--image (id)
  "Display image for note ID."
  (let* ((img (gnosis-get 'images 'extras `(= id ,id)))
	 (path-to-image (concat (file-name-as-directory gnosis-images-dir) img))
	 (image (create-image path-to-image 'png nil :width 500 :height 300)))
    (when img
      (with-gnosis-buffer
       (insert "\n\n")
       (insert-image image)))))

(cl-defun gnosis--prompt (prompt &optional (downcase nil) (split nil))
  "PROMPT user for input until `q' is given.

The user is prompted to provide input for the 'PROMPT' message.
Returns the list of non-'q' inputs in reverse order of their entry.

Set DOWNCASE to t to downcase all input given.
Set SPLIT to t to split all input given."
  (cl-loop with input = nil
           for response = (read-string (concat prompt " (q for quit): "))
	   do (if downcase (setf response (downcase response)))
           for response-parts = (if split (split-string response " ") (list response))
           if (member "q" response-parts) return (nreverse input)
           do (cl-loop for part in response-parts
	               unless (string-empty-p part)
                       do (push part input))))

(defun gnosis-add-deck (name)
  "Create deck with NAME."
  (interactive (list (read-string "Deck Name: ")))
  (when gnosis-testing
    (unless (y-or-n-p "You are using a testing environment! Continue?")
      (error "Aborted")))
  (if (gnosis-get 'name 'decks `(= name ,name))
      (error "Deck `%s' already exists" name)
    (gnosis--insert-into 'decks `([nil ,name]))
    (message "Created deck '%s'" name)))

(defun gnosis--get-deck-name ()
  "Return name from table DECKS."
  (when (equal (gnosis-select 'name 'decks) nil)
    (error "No decks found"))
  (completing-read "Deck: " (gnosis-select 'name 'decks)))

(cl-defun gnosis--get-deck-id (&optional (deck (gnosis--get-deck-name)))
  "Return id for DECK name."
  (gnosis-get 'id 'decks `(= name ,deck)))

(defun gnosis-delete-deck (deck)
  "Delete DECK."
  (interactive (list (gnosis--get-deck-name)))
  (gnosis--delete 'decks `(= name ,deck))
  (message "Deleted deck %s" deck))

(defun gnosis-suspend-note (id)
  "Suspend note with ID."
  (gnosis-update 'review-log '(= suspend 1) `(= id ,id)))

(cl-defun gnosis-suspend-deck (&optional (deck (gnosis--get-deck-id)))
  "Suspend all note(s) with DECK id.

When called with a prefix, unsuspends all notes in deck."
  (let ((notes (gnosis-select 'id 'notes `(= deck-id ,deck)))
	(suspend (if current-prefix-arg 0 1))
	(note-count 0))
    (cl-loop for note in notes
	     do (progn (gnosis-update 'review-log `(= suspend ,suspend) `(= id ,(car note)))
		       (setq note-count (1+ note-count)))
	     finally (if (equal suspend 0)
			 (message "Unsuspended %s notes" note-count)
		       (message "Suspended %s notes" note-count)))))

(defun gnosis-suspend-tag ()
  "Suspend all note(s) with tag.

When called with a prefix, unsuspends all notes for tag."
  (let ((notes (gnosis-select-by-tag (gnosis-tag-prompt nil t)))
	(suspend (if current-prefix-arg 0 1)))
    (cl-loop for note in notes
	     do (gnosis-update 'review-log `(= suspend ,suspend) `(= id ,note)))))

(defun gnosis-suspend ()
  "Suspend note(s) with specified values."
  (interactive)
  (let ((item (completing-read "Suspend by: " '("Deck" "Tag"))))
    (pcase item
      ("Deck" (gnosis-suspend-deck))
      ("Tag" (gnosis-suspend-tag))
      (_ (message "Not ready yet.")))))


(defun gnosis-add-note-fields (deck type main options answer extra tags suspend image second-image)
  "Add fields for new note.

DECK: Deck for new note.
TYPE: Note type e.g \"mcq\"
MAIN: Note's main part
OPTIONS: Note's options, e.g choices for mcq for OR hints for
cloze/basic type
ANSWER: Correct answer for note, for MCQ is an integer while for
cloze/basic a string/list of the right answer(s)
EXTRA: Extra information to display after answering note
TAGS: Tags to organize notes
SUSPEND: Integer value of 1 or 0, where 1 suspends the card
IMAGE: Image to display during review.
SECOND-IMAGE: Image to display after user-input."
  (gnosis--insert-into 'notes `([nil ,type ,main ,options ,answer ,tags ,(gnosis--get-deck-id deck)]))
  (gnosis--insert-into 'review `([nil ,gnosis-algorithm-ef ,gnosis-algorithm-ff ,gnosis-algorithm-interval]))
  (gnosis--insert-into 'review-log `([nil ,(gnosis-algorithm-date) ,(gnosis-algorithm-date) 0 0 0 0 ,suspend 0]))
  (gnosis--insert-into 'extras `([nil ,extra ,image ,second-image])))


;; Adding note(s) consists firstly of a hidden 'gnosis-add-note--TYPE'
;; function that does the computation & error checking to generate a
;; note from given input. Secondly, 'gnosis-add-note-TYPE' normal
;; function, which prompts for user input and passes it to the hidden
;; function.

(cl-defun gnosis-add-note--mcq (&key deck question choices correct-answer
				     extra (image nil) tags (suspend 0) (second-image nil))
  "Create a NOTE with a list of multiple CHOICES.

MCQ type consists of a main `QUESTION' that is displayed to the user.
The user will be prompted to select the correct answer from a list of
`CHOICES'. The `CORRECT-ANSWER' should be the index of the correct
choice in the `CHOICES' list. Each note must correspond to one `DECK'.

`IMAGE' Image to display before user-input
`SECOND-IMAGE' Image to display after user-input
`EXTRA' are extra information displayed after an answer is given.
`TAGS' are used to organize questions.
`SUSPEND' is a binary value, where 1 is for suspend."
  (cond ((or (not (numberp correct-answer)) (equal correct-answer 0))
	 (error "Correct answer value must be the index number of the correct answer"))
	((null tags)
	 (setf tags 'untagged)))
  (gnosis-add-note-fields deck "mcq" question choices correct-answer extra tags suspend image second-image))

(defun gnosis-add-note-mcq ()
  "Add note(s) of type `MCQ' interactively to selected deck.

Create a note type MCQ for specified deck, that consists of:
STEM: The question or problem statement
OPTIONS: Options for the user to select
ANSWER: Answer is the NUMBER of the correct answer of OPTIONS.
EXTRA: Information to display after user-input
TAGS: Used to organize notes

Refer to `gnosis-add-note--mcq' for more."
  (let ((deck (gnosis--get-deck-name)))
    (while (y-or-n-p (format "Add note of type `MCQ' to `%s' deck? " deck))
      (gnosis-add-note--mcq :deck deck
			    :question (read-string "Question: ")
			    :choices (gnosis--prompt "Choices")
			    :correct-answer (string-to-number (read-string "Which is the correct answer (number)? "))
			    :extra (read-string "Extra: ")
			    :tags (gnosis-tag-prompt)))))

(cl-defun gnosis-add-note--basic (&key deck question hint answer
				       extra (image nil) tags (suspend 0) (second-image nil))
  "Add Basic type note.

DECK: Deck name for note.
QUESTION: Quesiton to display for note.
ANSWER: Answer for QUESTION, which user will be prompted to type
HINT: Hint to display during review, before user-input.
EXTRA: Extra information to display after user-input/giving an answer.
IMAGE: Image to display before user-input.
TAGS: Tags used to organize notes
SUSPEND: Binary value of 0 & 1, when 1 note will be ignored."
  (gnosis-add-note-fields deck "basic" question hint answer extra tags suspend image second-image))

(defun gnosis-add-note-basic ()
  "Add note(s) of type `Basic' interactively to selected deck.

Basic note type is a flashcard-like note, where user first sees a
\"main\" part, which is usually a question, and he is prompted to
input the answer.

Refer to `gnosis-add-note--basic' for more."
  (let ((deck (gnosis--get-deck-name)))
    (while (y-or-n-p (format "Add note of type `basic' to `%s' deck? " deck))
      (gnosis-add-note--basic :deck deck
			      :question (read-string "Question: ")
			      :answer (read-string "Answer: ")
			      :hint (read-string "Hint: ")
			      :extra (read-string "Extra: ")
			      :tags (gnosis-tag-prompt)))))

(cl-defun gnosis-add-note--double (&key deck question hint answer extra (image nil) tags (suspend 0) (second-image nil))
  "Add Double type note.

Essentially, a \"note\" that generates 2 basic notes. The second one
reverses question/answer.

DECK: Deck name for note.
QUESTION: Quesiton to display for note.
ANSWER: Answer for QUESTION, which user will be prompted to type
HINT: Hint to display during review, before user-input.
EXTRA: Extra information to display after user-input/giving an answer.
IMAGE: Image to display before user-input.
TAGS: Tags used to organize notes
SUSPEND: Binary value of 0 & 1, when 1 note will be ignored."
  (gnosis-add-note-fields deck "basic" question hint answer extra tags suspend image second-image)
  (gnosis-add-note-fields deck "basic" answer hint question extra tags suspend image second-image))

(defun gnosis-add-note-double ()
  "Add note(s) of type double interactively to selected deck.

Essentially, a \"note\" that generates 2 basic notes. The second one
reverses question/answer.

Refer to `gnosis-add-note--double' for more."
  (let ((deck (gnosis--get-deck-name)))
    (while (y-or-n-p (format "Add note of type `double' to `%s' deck? " deck))
      (gnosis-add-note--double :deck deck
			       :question (read-string "Question: ")
			       :answer (read-string "Answer: ")
			       :image (when (y-or-n-p "Add image to display during review?")
					(completing-read "Select image: " (gnosis-directory-files)))
			       :hint (read-string "Hint: ")
			       :extra (read-string "Extra: ")
			       :tags (gnosis-tag-prompt)))))

(cl-defun gnosis-add-note--cloze (&key deck note hint tags (suspend 0) extra (image nil) (second-image nil))
  "Add cloze type note.

DECK: Deck name for note.
NOTE: Note with clozes, format for clozes is as follows:
      This is a {c1:cloze} note type.
      This is a {{c1::cloze}} note type.

Anki like syntax is supported with double brackets & double colon, as
well as single brackets({}) and colon(:), or even a mix.

For each cX: tag, there will be gerenated a cloze note type.
Example:
      {c1:Preformed enterotoxins} from
      {c2:Staphylococcus aureus} causes {c3:rapid} onset
      food poisoning

Generates 3 cloze note types. Where the \"main\" part of the note is the full
note, with the cloze(s) extracted & used as the \"answer\".

One cloze note may have multiple clozes
Example:
      {c1:Streptococcus agalactiae (GBS)} and {c1:Listeria
      monocytogenes} are CAMP test positive
   
HINT: Hint to display during review, before user-input.
   NOTE! In gnosis-db, hint is referred to as `options', same column
   options used in mcq.
IMAGE: Image to display before user-input.
TAGS: Tags used to organize notes
SUSPEND: When t, note will be ignored.
EXTRA: Extra information displayed after user-input.
SECOND-IMAGE: Image to display after user-input."
  (let ((notags-note (gnosis-cloze-remove-tags note))
	(clozes (gnosis-cloze-extract-answers note)))
    (cl-loop for cloze in clozes
	     do (gnosis-add-note-fields deck "cloze" notags-note hint cloze extra tags suspend image second-image))))

(defun gnosis-add-note-cloze ()
  "Add note(s) of type cloze interactively to selected deck.

Note with clozes, format for clozes is as follows:
      This is a {c1:cloze} note type.
      This is a {{c1::cloze}} note type.

Anki like syntax is supported with double brackes and colon, as well
as single brackets({}) and colon(:), or even a mix.

One cloze note may have multiple clozes
Example:
      {c1:Streptococcus agalactiae (GBS)} and {c1:Listeria
      monocytogenes} are CAMP test positive

For each cX: tag, there will be gerenated a cloze note type.
Example:
      {c1:Preformed enterotoxins} from
      {c2:Staphylococcus aureus} causes {c3:rapid} onset
      food poisoning

Generates 3 cloze note types. Where the \"main\" part of the note is
the full note, with the cloze(s) extracted & used as the \"answer\".

See `gnosis-add-note--cloze' for more reference."
  (let ((deck (gnosis--get-deck-name)))
    (while (y-or-n-p (format "Add note of type `cloze' to `%s' deck? " deck))
      (gnosis-add-note--cloze :deck deck
			      :note (read-string "Question: ")
			      :hint (read-string "Hint: ")
			      :extra (read-string "Extra: ")
			      :tags (gnosis-tag-prompt)))))

;;;###autoload
(defun gnosis-add-note (type)
  "Create note(s) as TYPE interactively."
  (interactive (list (completing-read "Type: " '(MCQ Cloze Basic Double) nil t)))
  (when gnosis-testing
    (unless (y-or-n-p "You are using a testing environment! Continue?")
      (error "Aborted")))
  (pcase type
    ("MCQ" (gnosis-add-note-mcq))
    ("Cloze" (gnosis-add-note-cloze))
    ("Basic" (gnosis-add-note-basic))
    ("Double" (gnosis-add-note-double))
    (_ (message "No such type."))))

(defun gnosis-export-deck (deck filename)
  "Export DECK as FILENAME.

Export all notes for DECK, in a file as FILENAME."
  (interactive (list (gnosis--get-deck-id)
		     (read-string "Name for exported file: ")))
  (let ((notes (gnosis-select '[type main options answer tags] 'notes `(= deck-id ,deck)))
	(default-directory gnosis-dir))
    (with-temp-file (concat filename ".el")
      (insert "(" (concat "gnosis-define-deck " "'" filename "\n"))
      (insert (pp-to-string notes) "\n")
      (insert ")" ))))

(defun gnosis-mcq-answer (id)
  "Choose the correct answer, from mcq choices for question ID."
  (let ((choices (gnosis-get 'options 'notes `(= id ,id)))
	(history-add-new-input nil)) ;; Disable history
    (completing-read "Answer: " choices)))

(defun gnosis-cloze-remove-tags (string)
  "Replace cx-tags in STRING.

Works both with {} and {{}} to make easier to import anki notes."
  (let* ((regex "{\\{1,2\\}c\\([0-9]+\\)::?\\(.*?\\)}\\{1,2\\}")
         (result (replace-regexp-in-string regex "\\2" string)))
    result))

(defun gnosis-cloze-replace-words (string words new)
  "In STRING replace WORDS with NEW."
  (cl-assert (listp words))
  (cl-loop for word
	   in words
	   do (setf string (replace-regexp-in-string (concat "\\<" word "\\>") ;; use word boundary indentifiers
						     new string)))
  string)

(defun gnosis-cloze-extract-answers (str)
  "Extract cloze answers for STR.

Return a list of cloze answers for STR, organized by cX-tag.

Valid cloze formats include:
\"This is an {c1:example}\"
\"This is an {c1::example}\"
\"This is an {{c1:example}}\"
\"This is an {{c1::example}}\""
  (let ((result-alist '())
        (start 0))
    (while (string-match "{\\{1,2\\}c\\([0-9]+\\)::?\\(.*?\\)}\\{1,2\\}" str start)
      (let* ((tag (match-string 1 str))
             (content (match-string 2 str)))
        (if (assoc tag result-alist)
            (push content (cdr (assoc tag result-alist)))
          (push (cons tag (list content)) result-alist))
        (setf start (match-end 0))))
    (mapcar (lambda (tag-group) (nreverse (cdr tag-group)))
	    (nreverse result-alist))))

(defun gnosis-compare-strings (str1 str2)
  "Compare STR1 and STR2.

Compare 2 strings, ignoring case and whitespace."
  (let ((modified-str1 (downcase (replace-regexp-in-string "\\s-" "" str1)))
        (modified-str2 (downcase (replace-regexp-in-string "\\s-" "" str2))))
    (string= modified-str1 modified-str2)))

(defun gnosis-directory-files (&optional dir regex)
  "Return a list of file paths, relative to DIR directory.

DIR is the base directory path from which to start the recursive search.
REGEX is the regular expression pattern to match the file names against.

This function traverses the subdirectories of DIR recursively,
collecting file paths that match the regular expression. The file
paths are returned as a list of strings, with each string representing
a relative file path to DIR.

By default, DIR value is `gnosis-images-dir' & REGEX value is \"^[^.]\""
  (let ((dir (or dir gnosis-images-dir))
	(regex (or regex "^[^.]")))
    (apply #'append
           (cl-loop for path in (directory-files dir t directory-files-no-dot-files-regexp)
                    if (file-directory-p path)
                    collect (mapcar (lambda (file) (concat (file-relative-name path dir) "/" file))
                                    (gnosis-directory-files path regex))
                    else if (string-match-p regex (file-name-nondirectory path))
                    collect (list (file-relative-name path dir))))))

(defun gnosis-select-image (&optional prompt)
  "Return PATH for file in `gnosis-images-dir'.

Optionally, add cusotm PROMPT."
  (let* ((prompt (or prompt "Select image: "))
	 (image (completing-read prompt (gnosis-directory-files gnosis-images-dir))))
    image))

(defun gnosis-get-tags--unique ()
  "Return a list of unique strings for tags in gnosis-db."
  (cl-loop for tags in (gnosis-select 'tags 'notes)
           nconc tags into all-tags
           finally return (delete-dups all-tags)))

(defun gnosis-select-by-tag (input-tags)
  "Return note id for every note with INPUT-TAGS."
  (unless (listp input-tags)
    (error "`input-tags' need to be a list"))
  (cl-loop for (id tags) in (emacsql gnosis-db [:select [id tags] :from notes])
           when (and (cl-every (lambda (tag) (member tag tags)) input-tags)
		     (not (gnosis-suspended-p id)))
           collect id))

(defun gnosis-suspended-p (id)
  "Return t if note with ID is suspended."
  (if (= (gnosis-get 'suspend 'review-log `(= id ,id)) 1)
      t
    nil))

(defun gnosis-get-deck-due-notes (&optional deck-id)
  "Return due notes for deck, with value of DECK-ID.

if DUE is t, return only due notes"
  (let* ((deck (or deck-id (gnosis--get-deck-id)))
	 (notes (gnosis-select 'id 'notes `(= deck-id ,deck))))
    (cl-loop for note in (apply #'append notes)
	     when (not (gnosis-suspended-p note))
	     collect note)))

(defun gnosis-tag-prompt (&optional prompt match)
  "PROMPT user to select tags, until they enter `q'.
Prompt user to select tags, generated from `gnosis-get-tags--unique'.

PROMPT: Prompt string value
MATCH: Require match, t or nil value

Returns a list of unique tags."
  (let* ((tags '())
         (tag "")
	 (prompt (or prompt "Selected tags"))
	 (match (or match nil)))
    (while (not (string= tag "q"))
      (setf tag (completing-read (concat prompt (format " %s (q for quit): " tags))
				 (cons "q" (gnosis-get-tags--unique)) nil match))
      (unless (or (string= tag "q") (member tag tags))
        (push tag tags)))
    (reverse tags)))

;; Review
;;;;;;;;;;
(defun gnosis-review--algorithm (id success)
  "Return next review date & ef for note with value of id ID.

SUCCESS is a binary value, 1 = success, 0 = failure.
Returns a list of the form ((yyyy mm dd) ef)."
  (let ((ff gnosis-algorithm-ff)
	(ef (nth 2 (gnosis-get 'ef 'review `(= id ,id))))
	(c-success (gnosis-get 'c-success 'review-log `(= id ,id))))
    (gnosis-algorithm-next-interval (gnosis-review--get-offset id)
				    (gnosis-get 'n 'review-log `(= id ,id))
				    ef success ff c-success)))

(defun gnosis-review-is-due-p (note-id)
  "Return t if unsuspended note with NOTE-ID is due today."
  (emacsql gnosis-db `[:select [id] :from review-log :where (and (<= next-rev ',(gnosis-algorithm-date))
								 (= suspend 0)
								 (= id ,note-id))]))

(defun gnosis-review-get-due-notes ()
  "Return a list due notes id for current date.

Select notes where:
 - Next review date <= current date
 - Not suspended."
  (apply #'append
	 (emacsql gnosis-db `[:select [id] :from review-log :where (and (<= next-rev ',(gnosis-algorithm-date))
								 (= suspend 0))])))

(defun gnosis-review-due-notes--with-tags ()
  "Return a list of due note tags."
  (let ((due-notes (gnosis-review-get-due-notes)))
    (cl-remove-duplicates
     (cl-mapcan (lambda (note-id)
                  (gnosis-get-note-tags note-id))
	        due-notes)
     :test 'equal)))

(defun gnosis-review--get-offset (id)
  "Return offset for note with value of id ID."
  (let ((last-rev (gnosis-get 'last-rev 'review-log `(= id ,id))))
    (gnosis-algorithm-date-diff last-rev)))

(defun gnosis-review-round (num)
  "Round NUM to 1 decimal.

This function is used to round floating point numbers to 1 decimal,
such as the easiness factor (ef)."
  (/ (round (* num 100.00)) 100.00))

(defun gnosis-review-new-ef (id success)
  "Return new ef for note with value of id ID.

SUCCESS is a binary value, 1 = success, 0 = failure.
Returns a list of the form (ef-increase ef-decrease ef)."
  (let ((ef (nth 1 (gnosis-review--algorithm id success)))
	(old-ef (gnosis-get 'ef 'review `(= id ,id))))
    (cl-substitute (gnosis-review-round ef) (nth 2 old-ef) old-ef)))

(defun gnosis-review--update (id success)
  "Update review-log for note with value of id ID.

SUCCESS is a binary value, 1 is for successful review."
  (let ((ef (gnosis-review-new-ef id 1)))
    ;; Update review-log
    (gnosis-update 'review-log `(= last-rev ',(gnosis-algorithm-date)) `(= id ,id))
    (gnosis-update 'review-log `(= next-rev ',(car (gnosis-review--algorithm id success))) `(= id ,id))
    (gnosis-update 'review-log `(= n (+ 1 ,(gnosis-get 'n 'review-log `(= id ,id)))) `(= id ,id))
    ;; Update review
    (gnosis-update 'review `(= ef ',ef) `(= id ,id))
    (if (= success 1)
	(progn (gnosis-update 'review-log `(= c-success ,(1+ (gnosis-get 'c-success 'review-log `(= id ,id)))) `(= id ,id))
	       (gnosis-update 'review-log `(= t-success ,(1+ (gnosis-get 't-success 'review-log `(= id ,id)))) `(= id ,id))
	       (gnosis-update 'review-log `(= c-fails 0) `(= id ,id)))
      (gnosis-update 'review-log `(= c-fails ,(1+ (gnosis-get 'c-fails 'review-log `(= id ,id)))) `(= id ,id))
      (gnosis-update 'review-log `(= t-fails ,(1+ (gnosis-get 't-fails 'review-log `(= id ,id)))) `(= id ,id))
      (gnosis-update 'review-log `(= c-success 0) `(= id ,id)))))

(defun gnosis-review-mcq (id)
  "Display multiple choice answers for question ID."
  (gnosis-display--image id)
  (gnosis-display--question id)
  (let* ((choices (gnosis-get 'options 'notes `(= id ,id)))
	 (answer (nth (- (gnosis-get 'answer 'notes `(= id ,id)) 1) choices))
	 (user-choice (gnosis-mcq-answer id)))
    (if (string= answer user-choice)
        (progn (gnosis-review--update id 1)
	       (message "Correct!"))
      (gnosis-review--update id 0)
      (message "False"))
    (gnosis-display--correct-answer-mcq answer user-choice)
    (gnosis-display--extra id)))

(defun gnosis-review-basic (id)
  "Review basic type note for ID."
  (gnosis-display--image id)
  (gnosis-display--question id)
  (gnosis-display--hint (gnosis-get 'options 'notes `(= id ,id)))
  (let* ((answer (gnosis-get 'answer 'notes `(= id ,id)))
	 (user-input (read-string "Answer: "))
	 (success (gnosis-compare-strings answer user-input)))
    (gnosis-display--basic-answer answer success user-input)
    (gnosis-display--extra id)
    (gnosis-review--update id (if success 1 0))))

(defun gnosis-review-cloze--input (cloze)
  "Prompt for user input during cloze review.

If user-input is equal to CLOZE, return t."
  (let ((user-input (read-string "Answer: ")))
    (cons (gnosis-compare-strings user-input cloze) user-input)))

(defun gnosis-review-cloze-reveal-unaswered (clozes)
  "Reveal CLOZES.

Used to reveal all clozes left with `gnosis-face-cloze-unanswered' face."
  (cl-loop for cloze in clozes do (gnosis-display-cloze-reveal :replace cloze
							       :face 'gnosis-face-cloze-unanswered)))

(defun gnosis-review-cloze (id)
  "Review cloze type note for ID."
  (let* ((main (gnosis-get 'main 'notes `(= id ,id)))
	 (clozes (gnosis-get 'answer 'notes `(= id ,id)))
	 (num 1)
	 (clozes-num (length clozes))
	 (hint (gnosis-get 'options 'notes `(= id ,id))))
    (gnosis-display--image id)
    (gnosis-display--cloze-sentence main clozes)
    (gnosis-display--hint hint)
    (cl-loop for cloze in clozes
	     do (let ((input (gnosis-review-cloze--input cloze)))
		  (if (equal (car input) t)
		      ;; Reveal only one cloze
		      (progn (gnosis-display-cloze-reveal :replace cloze)
			     (setf num (1+ num)))
		    ;; Reveal cloze for wrong input, with `gnosis-face-false'
		    (gnosis-display-cloze-reveal :replace cloze :success nil)
		    ;; Do NOT remove the _when_ statement, unexpected
		    ;; bugs occur if so depending on the number of
		    ;; clozes.
		    (when (< num clozes-num) (gnosis-review-cloze-reveal-unaswered clozes))
		    (gnosis-display-cloze-user-answer (cdr input))
		    (gnosis-review--update id 0)
		    (cl-return)))
	     finally (gnosis-review--update id 1)))
  (gnosis-display--extra id))

(defun gnosis-review-note (id)
  "Start review for note with value of id ID, if note is unsuspended."
  (cond ((gnosis-suspended-p id)
         (message "Note is suspended."))
        (t
         (let ((type (gnosis-get 'type 'notes `(= id ,id))))
           (pcase type
             ("mcq" (gnosis-review-mcq id))
             ("basic" (gnosis-review-basic id))
             ("cloze" (gnosis-review-cloze id))
             (_ (error "Malformed note type")))))))

(defun gnosis-review-commit (note-num)
  "Commit review session on git repository.

This function initializes the `gnosis-dir' as a Git repository if it is not
already one. It then adds the gnosis.db file to the repository and commits
the changes with a message containing the reviewed number of notes.

NOTE-NUM: The number of notes reviewed in the session."
  (let ((git (executable-find "git"))
	(default-directory gnosis-dir))
    (unless git
      (error "Git not found, please install git"))
    (unless (file-exists-p (concat (file-name-as-directory gnosis-dir) ".git"))
      (shell-command "git init"))
    (sit-for 0.2) ;; wait for shell command to finish
    (shell-command (concat git " add " (shell-quote-argument "gnosis.db")))
    (shell-command (concat git " commit -m "
			   (shell-quote-argument (concat (format "Total notes for session: %d " note-num)))))
    (message "Review session finished. %d notes reviewed." note-num)))

(defun gnosis-review--session (notes)
  "Start review session for NOTES."
  (when (null notes)
    (message "No due notes."))
  (let ((note-count 0))
    (when (y-or-n-p (format "You have %s total notes for review, start session?" (length notes)))
      (cl-loop for note in notes
	       do (progn (gnosis-review-note note)
			 (setf note-count (1+ note-count))
			 (pcase (read-char-choice "Note Action: [n]ext, [s]uspend, [e]dit, [q]uit: " '(?n ?s ?e ?q))
			   (?n nil)
			   (?s (gnosis-suspend-note note))
			   (?e (progn (gnosis-edit-note note)
				      (recursive-edit)))
			   (?q (progn (gnosis-review-commit note-count)
				      (cl-return)))))
	       finally (gnosis-review-commit note-count)))))


;; Editing notes

(defun gnosis-edit-note (id)
  "Edit note with value of id ID."
  (pcase (completing-read "Edit: " '(contents ef) nil t)
    ("contents" (gnosis-edit-note-contents id))
    ("ef" (gnosis-edit-ef id))
    (_ (message "No such value."))))

(defun gnosis-edit-ef (id)
  "Edit easiness factor values for note with id value ID."
  (let ((ef-full (caar (gnosis-select 'ef 'review `(= id ,id))))
	(old-value-index (pcase (completing-read "Change Factor: " '("Increase" "Decrease" "Total"))
			   ("Total" 2)
			   ("Decrease" 1)
			   ("Increase" 0)))
	(new-value (float (string-to-number (read-string "New value: ")))))
    ;; error checking.
    (cond ((>= 0 new-value) (error "New value needs to be a number & higher than `0'"))
	  ;; Check if when total-ef is selected, new value is higher than 1.3
	  ((and (>= 1.3 new-value) (= old-value-index 2) (error "New total ef needs to be higher than `1.3'"))))
    ;; Use `gnosis-replace-item-at-index' to generate new list with
    ;; new ef value. Change ef value at gnosis-db using
    ;; `gnosis-update'
    (gnosis-update 'review `(= ef ',(gnosis-replace-item-at-index old-value-index new-value ef-full)) `(= id ,id))))

(defun gnosis-edit-note-contents (id)
  "Edit the contents of a note with the given ID.

This function creates an Emacs Lisp buffer named *gnosis-edit* and populates it
with the values of the note identified by the specified ID. The note values are
inserted as keywords for the `gnosis-edit-update-note' function.

To make changes, edit the values in the buffer, and then evaluate the
`gnosis-edit-update-note' expression to save the changes.

The note fields that will be shown in the buffer are:
   - ID: The identifier of the note.
   - MAIN: The main content of the note.
   - OPTIONS: Additional options related to the note.
   - ANSWER: The answer associated with the note.
   - TAGS: The tags assigned to the note.
   - EXTRA-NOTES: Any extra notes for the note.
   - IMAGE: An image associated with the note.
   - SECOND-IMAGE: Another image associated with the note.

The buffer automatically indents the expressions for readability.
After finishing editing, evaluate the entire expression to apply the
changes."
  (let ((id (gnosis-get 'id 'notes `(= id ,id)))
	(main (gnosis-get 'main 'notes `(= id ,id)))
	(options (gnosis-get 'options 'notes `(= id ,id)))
	(answer (gnosis-get 'answer 'notes `(= id ,id)))
	(tags (gnosis-get 'tags 'notes `(= id ,id)))
	(extra-notes (gnosis-get 'extra-notes 'extras `(= id ,id)))
	(image (gnosis-get 'images 'extras `(= id ,id)))
	(second-image (gnosis-get 'extra-image 'extras `(= id ,id))))
    (with-current-buffer (switch-to-buffer (get-buffer-create "*gnosis-edit*"))
      (gnosis-edit-mode)
      (erase-buffer)
      (insert ";;\n;; You are editing a gnosis note. DO NOT change the value of id.\n\n")
      (insert "(gnosis-edit-update-note ")
      (cl-loop for (field value) in `((id ,id)
				      (main ,main)
				      (options ,options)
				      (answer ,answer)
				      (tags ,tags)
				      (extra-notes ,extra-notes)
				      (image ,image)
				      (second-image ,second-image))
	       do (cond ((numberp value)
			 (insert (format ":%s %s\n" field value)))
			((and (listp value)
			      (not (equal value nil)))
			 (insert (format ":%s '%s\n" field (format "%s" (cl-loop for item in value
										collect (format "\"%s\"" item))))))
			((equal value nil)
			 (insert (format ":%s %s\n" field 'nil)))
			(t (insert (format ":%s \"%s\"\n" field value)))))
      (delete-char -1) ;; delete extra line
      (insert ")")
      (insert "\n;; After finishing editing, save changes with `<C-c> <C-c>'\n;; Do NOT exit without saving.")
      (indent-region (point-min) (point-max)))))

(define-derived-mode gnosis-edit-mode emacs-lisp-mode "Gnosis EDIT"
  "Gnosis Edit Mode."
  :interactive t
  :lighter " gnosis-edit-mode"
  :keymap gnosis-edit-mode-map)

(defvar-keymap gnosis-edit-mode-map
  :doc "gnosis-edit keymap"
  "C-c C-c" #'(lambda () (interactive) (eval-buffer) (kill-buffer) (throw 'exit nil)))


(cl-defun gnosis-edit-update-note (&key id main options answer tags (extra-notes nil) (image nil) (second-image nil))
  "Update note with id value of ID.

ID: Note id
MAIN: Main part of note, the stem part of MCQ, question for basic, etc.
OPTIONS: Options for mcq type notes/Hint for basic & cloze type notes
ANSWER: Answer for MAIN, user is asked for input, if equal user-input
= answer review is marked as successfull
TAGS: Tags for note, used to organize & differentiate between notes
EXTRA-NOTES: Notes to display after user-input
IMAGE: Image to display before user-input
SECOND-IMAGE: Image to display after user-input"
  ;; Construct the update clause for the emacsql update statement.
  (cl-loop for (field . value) in
           `((main . ,main)
             (options . ,options)
             (answer . ,answer)
             (tags . ,tags)
             (extra-notes . ,extra-notes)
             (image . ,image)
             (second-image . ,second-image))
           when value
           do (cond ((member field '(extra-notes image second-image))
		     (gnosis-update 'extras `(= ,field ,value) `(= id ,id)))
		    ((listp value)
		     (gnosis-update 'notes `(= ,field ',value) `(= id ,id)))
		    (t (gnosis-update 'notes `(= ,field ,value) `(= id ,id))))))


;;;###autoload
(defun gnosis-review ()
  "Start gnosis review session."
  (interactive)
  (gnosis-db-init)
  (let ((review-type (completing-read "Review: " '("Due notes"
						   "Due notes of specified tag(s)"
						   "Notes with tag(s)"))))
    (pcase review-type
      ("Due notes" (gnosis-review--session (gnosis-review-get-due-notes)))
      ("Due notes of specified tag(s)" (gnosis-review--session
					(gnosis-select-by-tag
					 (list (completing-read "Start session for tag: "
								(gnosis-review-due-notes--with-tags))))))
      ("All notes of tag(s)" (gnosis-review--session (gnosis-select-by-tag (gnosis-tag-prompt nil t)))))))

;;; Database Schemas
(defvar gnosis-db-schema-decks '([(id integer :primary-key :autoincrement)
				  (name text :not-null)]))

(defvar gnosis-db-schema-notes '([(id integer :primary-key :autoincrement)
				  (type text :not-null)
				  (main text :not-null)
				  (options text :not-null)
				  (answer text :not-null)
				  (tags text :default untagged)
				  (deck-id integer :not-null)]
				 (:foreign-key [deck-id] :references decks [id]
					       :on-delete :cascade)))

(defvar gnosis-db-schema-review '([(id integer :primary-key :not-null) ;; note-id
				   (ef integer :not-null) ;; Easiness factor
				   (ff integer :not-null) ;; Forgetting factor
				   (interval integer :not-null)] ;; Interval
				  (:foreign-key [id] :references notes [id]
						:on-delete :cascade)))

(defvar gnosis-db-schema-review-log '([(id integer :primary-key :not-null) ;; note-id
				       (last-rev integer :not-null)  ;; Last review date
				       (next-rev integer :not-null)  ;; Next review date
				       (c-success integer :not-null) ;; number of consecutive successful reviews
				       (t-success integer :not-null) ;; Number of total successful reviews
				       (c-fails integer :not-null)   ;; Number of consecutive failed reviewss
				       (t-fails integer :not-null)   ;; Number of total failed reviews
				       (suspend integer :not-null)   ;; Binary value, 1=suspended
				       (n integer :not-null)]        ;; Number of reviews
				      (:foreign-key [id] :references notes [id]
						    :on-delete :cascade)))

(defvar gnosis-db-schema-extras '([(id integer :primary-key :not-null)
				   (extra-notes string)
				   (images string)
				   (extra-image string)]
				  (:foreign-key [id] :references notes [id]
						:on-delete :cascade)))

(defun gnosis-db-init ()
  "Create gnosis essential directories & database."
  ;; Create gnosis-dir
  (unless (file-exists-p gnosis-dir)
    (make-directory gnosis-dir)
    (make-directory gnosis-images-dir)
    ;; Make sure gnosis-db is initialized
    (setf gnosis-db (emacsql-sqlite (concat (file-name-as-directory gnosis-dir) "gnosis.db"))))
  ;; Create database tables
  (unless (length= (emacsql gnosis-db [:select name :from sqlite-master :where (= type table)]) 6)
    ;; Enable foreign keys
    (emacsql gnosis-db "PRAGMA foreign_keys = ON")
    ;; Gnosis version
    (emacsql gnosis-db (format "PRAGMA user_version = %s" gnosis-db-version))
    ;; Create decks table
    (gnosis--create-table 'decks gnosis-db-schema-decks)
    ;; Create notes table
    (gnosis--create-table 'notes gnosis-db-schema-notes)
    ;; Create review table
    (gnosis--create-table 'review gnosis-db-schema-review)
    ;; Create review-log table
    (gnosis--create-table 'review-log gnosis-db-schema-review-log)
    ;; Create extras table
    (gnosis--create-table 'extras gnosis-db-schema-extras)))

;; Gnosis mode ;;
;;;;;;;;;;;;;;;;;

(define-derived-mode gnosis-mode special-mode "Gnosis"
  "Gnosis Mode."
  :interactive t
  (read-only-mode 0)
  (display-line-numbers-mode 0)
  :lighter " gnosis-mode")


(provide 'gnosis)
;;; gnosis.el ends here