1 ;;; srecode/fields.el --- Handling type-in fields in a buffer.
3 ;; Copyright (C) 2009-2013 Free Software Foundation, Inc.
5 ;; Author: Eric M. Ludlam <eric@siege-engine.com>
7 ;; This file is part of GNU Emacs.
9 ;; GNU Emacs is free software: you can redistribute it and/or modify
10 ;; it under the terms of the GNU General Public License as published by
11 ;; the Free Software Foundation, either version 3 of the License, or
12 ;; (at your option) any later version.
14 ;; GNU Emacs is distributed in the hope that it will be useful,
15 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
16 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 ;; GNU General Public License for more details.
19 ;; You should have received a copy of the GNU General Public License
20 ;; along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>.
24 ;; Idea courtesy of yasnippets.
26 ;; If someone prefers not to type unknown dictionary entries into
27 ;; mini-buffer prompts, it could instead use in-buffer fields.
29 ;; A template-region specifies an area in which the fields exist. If
30 ;; the cursor exits the region, all fields are cleared.
32 ;; Each field is independent, but some are linked together by name.
33 ;; Typing in one will cause the matching ones to change in step.
35 ;; Each field has 2 overlays. The second overlay allows control in
36 ;; the character just after the field, but does not highlight it.
38 ;; @TODO - Cancel an old field array if a new one is about to be created!
40 ;; Keep this library independent of SRecode proper.
44 (defvar srecode-field-archive nil
45 "While inserting a set of fields, collect in this variable.
46 Once an insertion set is done, these fields will be activated.")
52 (defface srecode-field-face
53 '((((class color
) (background dark
))
55 (((class color
) (background light
))
56 (:underline
"green4")))
57 "*Face used to specify editable fields from a template."
58 :group
'semantic-faces
)
60 (defcustom srecode-fields-exit-confirmation nil
61 "Ask for confirmation before leaving field editing mode."
67 ;; Fields and the template region share some basic overlay features.
69 (defclass srecode-overlaid
()
70 ((overlay :documentation
71 "Overlay representing this field.
72 The overlay will crossreference this object.")
74 "An object that gets automatically bound to an overlay.
75 Has virtual :start and :end initializers.")
77 (defmethod initialize-instance ((olaid srecode-overlaid
) &optional args
)
78 "Initialize OLAID, being sure it archived."
79 ;; Extract :start and :end from the olaid list.
86 (cond ((eq (car args
) :start
)
87 (setq args
(cdr args
))
88 (setq start
(car args
))
89 (setq args
(cdr args
))
92 (setq args
(cdr args
))
94 (setq args
(cdr args
))
97 (push (car args
) newargs
)
98 (setq args
(cdr args
))
99 (push (car args
) newargs
)
100 (setq args
(cdr args
)))
103 ;; Create a temporary overlay now. We have to use an overlay and
104 ;; not a marker because of the in-front insertion rules. The rules
105 ;; are backward from what is wanted while typing.
106 (setq olay
(make-overlay start end
(current-buffer) t nil
))
107 (overlay-put olay
'srecode-init-only t
)
109 (oset olaid overlay olay
)
110 (call-next-method olaid
(nreverse newargs
))
114 (defmethod srecode-overlaid-activate ((olaid srecode-overlaid
))
115 "Activate the overlaid area."
116 (let* ((ola (oref olaid overlay
))
117 (start (overlay-start ola
))
118 (end (overlay-end ola
))
119 ;; Create a new overlay here.
120 (ol (make-overlay start end
(current-buffer) nil t
)))
122 ;; Remove the old one.
125 (overlay-put ol
'srecode olaid
)
127 (oset olaid overlay ol
)
131 (defmethod srecode-delete ((olaid srecode-overlaid
))
132 "Delete the overlay from OLAID."
133 (delete-overlay (oref olaid overlay
))
134 (slot-makeunbound olaid
'overlay
)
137 (defmethod srecode-empty-region-p ((olaid srecode-overlaid
))
138 "Return non-nil if the region covered by OLAID is of length 0."
139 (= 0 (srecode-region-size olaid
)))
141 (defmethod srecode-region-size ((olaid srecode-overlaid
))
142 "Return the length of region covered by OLAID."
143 (let ((start (overlay-start (oref olaid overlay
)))
144 (end (overlay-end (oref olaid overlay
))))
147 (defmethod srecode-point-in-region-p ((olaid srecode-overlaid
))
148 "Return non-nil if point is in the region of OLAID."
149 (let ((start (overlay-start (oref olaid overlay
)))
150 (end (overlay-end (oref olaid overlay
))))
151 (and (>= (point) start
) (<= (point) end
))))
153 (defun srecode-overlaid-at-point (class)
154 "Return a list of overlaid fields of type CLASS at point."
155 (let ((ol (overlays-at (point)))
158 (let ((tmp (overlay-get (car ol
) 'srecode
)))
159 (when (and tmp
(object-of-class-p tmp class
))
160 (setq ret
(cons tmp ret
))))
162 (car (nreverse ret
))))
164 (defmethod srecode-overlaid-text ((olaid srecode-overlaid
) &optional set-to
)
165 "Return the text under OLAID.
166 If SET-TO is a string, then replace the text of OLAID wit SET-TO."
167 (let* ((ol (oref olaid overlay
))
168 (start (overlay-start ol
)))
169 (if (not (stringp set-to
))
171 (buffer-substring-no-properties start
(overlay-end ol
))
174 (delete-region start
(overlay-end ol
))
177 (move-overlay ol start
(+ start
(length set-to
))))
182 ;; Managing point-exit, and flushing fields.
184 (defclass srecode-template-inserted-region
(srecode-overlaid)
185 ((fields :documentation
186 "A list of field overlays in this region.")
187 (active-region :allocation
:class
190 "The template region currently being handled.")
192 "Manage a buffer region in which fields exist.")
194 (defmethod initialize-instance ((ir srecode-template-inserted-region
)
196 "Initialize IR, capturing the active fields, and creating the overlay."
197 ;; Fill in the fields
198 (oset ir fields srecode-field-archive
)
199 (setq srecode-field-archive nil
)
201 ;; Initialize myself first.
205 (defmethod srecode-overlaid-activate ((ir srecode-template-inserted-region
))
206 "Activate the template area for IR."
207 ;; Activate all our fields
209 (dolist (F (oref ir fields
))
210 (srecode-overlaid-activate F
))
212 ;; Activate our overlay.
215 ;; Position the cursor at the first field
216 (let ((first (car (oref ir fields
))))
217 (goto-char (overlay-start (oref first overlay
))))
219 ;; Set ourselves up as 'active'
220 (oset ir active-region ir
)
222 ;; Setup the post command hook.
223 (add-hook 'post-command-hook
'srecode-field-post-command t t
)
226 (defmethod srecode-delete ((ir srecode-template-inserted-region
))
227 "Call into our base, but also clear out the fields."
228 ;; Clear us out of the baseclass.
229 (oset ir active-region nil
)
231 (mapc 'srecode-delete
(oref ir fields
))
235 (remove-hook 'post-command-hook
'srecode-field-post-command t
)
238 (defsubst srecode-active-template-region
()
239 "Return the active region for template fields."
240 (oref srecode-template-inserted-region active-region
))
242 (defun srecode-field-post-command ()
243 "Srecode field handler in the post command hook."
244 (let ((ar (srecode-active-template-region))
247 ;; Find a bug and fix it.
248 (remove-hook 'post-command-hook
'srecode-field-post-command t
)
249 (if (srecode-point-in-region-p ar
)
251 ;; We moved out of the template. Cancel the edits.
252 (srecode-delete ar
)))
257 (defclass srecode-field
(srecode-overlaid)
258 ((tail :documentation
259 "Overlay used on character just after this field.
260 Used to provide useful keybindings there.")
263 "The name of this field.
264 Usually initialized from the dictionary entry name that
265 the users needs to edit.")
266 (prompt :initarg
:prompt
268 "A prompt string to use if this were in the minibuffer.
269 Display when the cursor enters this field.")
270 (read-fcn :initarg
:read-fcn
272 "A function that would be used to read a string.
273 Try to use this to provide useful completion when available.")
275 "Representation of one field.")
277 (defvar srecode-field-keymap
278 (let ((km (make-sparse-keymap)))
279 (define-key km
"\C-i" 'srecode-field-next
)
280 (define-key km
"\M-\C-i" 'srecode-field-prev
)
281 (define-key km
"\C-e" 'srecode-field-end
)
282 (define-key km
"\C-a" 'srecode-field-start
)
283 (define-key km
"\M-m" 'srecode-field-start
)
284 (define-key km
"\C-c\C-c" 'srecode-field-exit-ask
)
286 "Keymap applied to field overlays.")
288 (defmethod initialize-instance ((field srecode-field
) &optional args
)
289 "Initialize FIELD, being sure it archived."
290 (add-to-list 'srecode-field-archive field t
)
294 (defmethod srecode-overlaid-activate ((field srecode-field
))
295 "Activate the FIELD area."
298 (let* ((ol (oref field overlay
))
301 (overlay-put ol
'face
'srecode-field-face
)
302 (overlay-put ol
'keymap srecode-field-keymap
)
303 (overlay-put ol
'modification-hooks
'(srecode-field-mod-hook))
304 (overlay-put ol
'insert-behind-hooks
'(srecode-field-behind-hook))
305 (overlay-put ol
'insert-in-front-hooks
'(srecode-field-mod-hook))
307 (setq end
(overlay-end ol
))
308 (setq tail
(make-overlay end
(+ end
1) (current-buffer)))
310 (overlay-put tail
'srecode field
)
311 (overlay-put tail
'keymap srecode-field-keymap
)
312 (overlay-put tail
'face
'srecode-field-face
)
313 (oset field tail tail
)
317 (defmethod srecode-delete ((olaid srecode-field
))
318 "Delete our secondary overlay."
319 ;; Remove our spare overlay
320 (delete-overlay (oref olaid tail
))
321 (slot-makeunbound olaid
'tail
)
322 ;; Do our baseclass work.
326 (defvar srecode-field-replication-max-size
100
327 "Maximum size of a field before canceling replication.")
329 (defun srecode-field-mod-hook (ol after start end
&optional pre-len
)
330 "Modification hook for the field overlay.
332 AFTER is non-nil if it is called after the change.
333 START and END are the bounds of the change.
334 PRE-LEN is used in the after mode for the length of the changed text."
335 (when (and after
(not undo-in-progress
))
336 (let* ((field (overlay-get ol
'srecode
))
337 (inhibit-point-motion-hooks t
)
338 (inhibit-modification-hooks t
)
340 ;; Sometimes a field is deleted, but we might still get a stray
341 ;; event. Let's just ignore those events.
342 (when (slot-boundp field
'overlay
)
343 ;; First, fixup the two overlays, in case they got confused.
344 (let ((main (oref field overlay
))
345 (tail (oref field tail
)))
348 (1- (overlay-end tail
)))
350 (1- (overlay-end tail
))
352 ;; Now capture text from the main overlay, and propagate it.
353 (let* ((new-text (srecode-overlaid-text field
))
354 (region (srecode-active-template-region))
355 (allfields (when region
(oref region fields
)))
356 (name (oref field name
)))
357 (dolist (F allfields
)
358 (when (and (not (eq F field
))
359 (string= name
(oref F name
)))
360 (if (> (length new-text
) srecode-field-replication-max-size
)
361 (message "Field size too large for replication.")
362 ;; If we find other fields with the same name, then keep
363 ;; then all together. Disable change hooks to make sure
364 ;; we don't get a recursive edit.
365 (srecode-overlaid-text F new-text
)
369 (defun srecode-field-behind-hook (ol after start end
&optional pre-len
)
370 "Modification hook for the field overlay.
372 AFTER is non-nil if it is called after the change.
373 START and END are the bounds of the change.
374 PRE-LEN is used in the after mode for the length of the changed text."
376 (let* ((field (overlay-get ol
'srecode
))
378 (move-overlay ol
(overlay-start ol
) end
)
379 (srecode-field-mod-hook ol after start end pre-len
))
382 (defmethod srecode-field-goto ((field srecode-field
))
384 (goto-char (overlay-start (oref field overlay
))))
386 (defun srecode-field-next ()
387 "Move to the next field."
389 (let* ((f (srecode-overlaid-at-point 'srecode-field
))
390 (tr (srecode-overlaid-at-point 'srecode-template-inserted-region
))
392 (when (not f
) (error "Not in a field"))
393 (when (not tr
) (error "Not in a template region"))
395 (let ((fields (oref tr fields
)))
397 ;; Loop over fields till we match. Then move to the next one.
398 (when (eq f
(car fields
))
400 (srecode-field-goto (car (cdr fields
)))
401 (srecode-field-goto (car (oref tr fields
))))
404 (setq fields
(cdr fields
))))
407 (defun srecode-field-prev ()
408 "Move to the prev field."
410 (let* ((f (srecode-overlaid-at-point 'srecode-field
))
411 (tr (srecode-overlaid-at-point 'srecode-template-inserted-region
))
413 (when (not f
) (error "Not in a field"))
414 (when (not tr
) (error "Not in a template region"))
416 (let ((fields (reverse (oref tr fields
))))
418 ;; Loop over fields till we match. Then move to the next one.
419 (when (eq f
(car fields
))
421 (srecode-field-goto (car (cdr fields
)))
422 (srecode-field-goto (car (oref tr fields
))))
425 (setq fields
(cdr fields
))))
428 (defun srecode-field-end ()
429 "Move to the end of this field."
431 (let* ((f (srecode-overlaid-at-point 'srecode-field
)))
432 (goto-char (overlay-end (oref f overlay
)))))
434 (defun srecode-field-start ()
435 "Move to the end of this field."
437 (let* ((f (srecode-overlaid-at-point 'srecode-field
)))
438 (goto-char (overlay-start (oref f overlay
)))))
440 (defun srecode-field-exit-ask ()
441 "Ask if the user wants to exit field-editing mini-mode."
443 (when (or (not srecode-fields-exit-confirmation
)
444 (y-or-n-p "Exit field-editing mode? "))
445 (srecode-delete (srecode-active-template-region))))
448 (provide 'srecode
/fields
)
451 ;; generated-autoload-load-name: "srecode/fields"
454 ;;; srecode/fields.el ends here