1;;; encoded-kb.el --- handler to input multibyte characters encoded somehow
2
3;; Copyright (C) 1997, 2001, 2002, 2003, 2004, 2005, 2006, 2007
4;;   Free Software Foundation, Inc.
5;; Copyright (C) 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004,
6;;   2005, 2006, 2007
7;;   National Institute of Advanced Industrial Science and Technology (AIST)
8;;   Registration Number H14PRO021
9
10;; This file is part of GNU Emacs.
11
12;; GNU Emacs is free software; you can redistribute it and/or modify
13;; it under the terms of the GNU General Public License as published by
14;; the Free Software Foundation; either version 2, or (at your option)
15;; any later version.
16
17;; GNU Emacs is distributed in the hope that it will be useful,
18;; but WITHOUT ANY WARRANTY; without even the implied warranty of
19;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
20;; GNU General Public License for more details.
21
22;; You should have received a copy of the GNU General Public License
23;; along with GNU Emacs; see the file COPYING.  If not, write to the
24;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
25;; Boston, MA 02110-1301, USA.
26
27;;; Commentary:
28
29;;; Code:
30
31;; Usually this map is empty (even if Encoded-kbd mode is on), but if
32;; the keyboard coding system is iso-2022-based, it defines dummy key
33;; bindings for ESC $ ..., etc. so that those bindings in
34;; key-translation-map take effect.
35(defconst encoded-kbd-mode-map (make-sparse-keymap)
36  "Keymap for Encoded-kbd minor mode.")
37
38;; Subsidiary keymaps for handling ISO2022 escape sequences.
39
40(defvar encoded-kbd-iso2022-esc-map
41  (let ((map (make-sparse-keymap)))
42    (define-key map "$" 'encoded-kbd-iso2022-esc-dollar-prefix)
43    (define-key map "(" 'encoded-kbd-iso2022-designation-prefix)
44    (define-key map ")" 'encoded-kbd-iso2022-designation-prefix)
45    (define-key map "," 'encoded-kbd-iso2022-designation-prefix)
46    (define-key map "-" 'encoded-kbd-iso2022-designation-prefix)
47    map)
48  "Keymap for handling ESC code in Encoded-kbd mode.")
49(fset 'encoded-kbd-iso2022-esc-prefix encoded-kbd-iso2022-esc-map)
50
51(defvar encoded-kbd-iso2022-esc-dollar-map
52  (let ((map (make-sparse-keymap)))
53    (define-key map "(" 'encoded-kbd-iso2022-designation-prefix)
54    (define-key map ")" 'encoded-kbd-iso2022-designation-prefix)
55    (define-key map "," 'encoded-kbd-iso2022-designation-prefix)
56    (define-key map "-" 'encoded-kbd-iso2022-designation-prefix)
57    (define-key map "@" 'encoded-kbd-iso2022-designation)
58    (define-key map "A" 'encoded-kbd-iso2022-designation)
59    (define-key map "B" 'encoded-kbd-iso2022-designation)
60    map)
61  "Keymap for handling ESC $ sequence in Encoded-kbd mode.")
62(fset 'encoded-kbd-iso2022-esc-dollar-prefix
63      encoded-kbd-iso2022-esc-dollar-map)
64
65(defvar encoded-kbd-iso2022-designation-map
66  (let ((map (make-sparse-keymap))
67	(l charset-list)
68	final-char)
69    (while l
70      (setq final-char (charset-iso-final-char (car l)))
71      (if (> final-char 0)
72	  (define-key map (char-to-string final-char)
73	    'encoded-kbd-iso2022-designation))
74      (setq l (cdr l)))
75    map)
76  "Keymap for handling ISO2022 designation sequence in Encoded-kbd mode.")
77(fset 'encoded-kbd-iso2022-designation-prefix
78      encoded-kbd-iso2022-designation-map)
79
80;; Keep information of designation state of ISO2022 encoding.  When
81;; Encoded-kbd mode is on, this is set to a vector of length 4, the
82;; elements are character sets currently designated to graphic
83;; registers 0 thru 3.
84
85(defvar encoded-kbd-iso2022-designations nil)
86(put 'encoded-kbd-iso2022-designations 'permanent-local t)
87
88;; Keep information of invocation state of ISO2022 encoding.  When
89;; Encoded-kbd mode is on, this is set to a vector of length 3,
90;; graphic register numbers currently invoked to graphic plane 1 and
91;; 2, and a single shifted graphic register number.
92
93(defvar encoded-kbd-iso2022-invocations nil)
94(put 'encoded-kbd-iso2022-invocations 'permanent-local t)
95
96(defsubst encoded-kbd-last-key ()
97  (let ((keys (this-single-command-keys)))
98    (aref keys (1- (length keys)))))
99
100(defun encoded-kbd-iso2022-designation (ignore)
101  "Do ISO2022 designation according to the current key in Encoded-kbd mode.
102The following key sequence may cause multilingual text insertion."
103  (let ((key-seq (this-single-command-keys))
104	(prev-g0-charset (aref encoded-kbd-iso2022-designations
105			       (aref encoded-kbd-iso2022-invocations 0)))
106	intermediate-char final-char
107	reg dimension chars charset)
108    (if (= (length key-seq) 4)
109	;; ESC $ <intermediate-char> <final-char>
110	(setq intermediate-char (aref key-seq 2)
111	      dimension 2
112	      chars (if (< intermediate-char ?,) 94 96)
113	      final-char (aref key-seq 3)
114	      reg (mod intermediate-char 4))
115      (if (= (aref key-seq 1) ?$)
116	  ;; ESC $ <final-char>
117	  (setq dimension 2
118		chars 94
119		final-char (aref key-seq 2)
120		reg 0)
121	;; ESC <intermediate-char> <final-char>
122	(setq intermediate-char (aref key-seq 1)
123	      dimension 1
124	      chars (if (< intermediate-char ?,) 94 96)
125	      final-char (aref key-seq 2)
126	      reg (mod intermediate-char 4))))
127    (aset encoded-kbd-iso2022-designations reg
128	  (iso-charset dimension chars final-char)))
129  "")
130
131(defun encoded-kbd-iso2022-single-shift (ignore)
132  (let ((char (encoded-kbd-last-key)))
133    (aset encoded-kbd-iso2022-invocations 2 (if (= char ?\216) 2 3)))
134  "")
135
136(defun encoded-kbd-self-insert-iso2022-7bit (ignore)
137  (let ((char (encoded-kbd-last-key))
138	(charset (aref encoded-kbd-iso2022-designations
139		       (or (aref encoded-kbd-iso2022-invocations 2)
140			   (aref encoded-kbd-iso2022-invocations 0)))))
141    (aset encoded-kbd-iso2022-invocations 2 nil)
142    (vector (if (= (charset-dimension charset) 1)
143		(make-char charset char)
144	      (make-char charset char (read-char-exclusive))))))
145
146(defun encoded-kbd-self-insert-iso2022-8bit (ignore)
147  (let ((char (encoded-kbd-last-key))
148	(charset (aref encoded-kbd-iso2022-designations
149		       (or (aref encoded-kbd-iso2022-invocations 2)
150			   (aref encoded-kbd-iso2022-invocations 1)))))
151    (aset encoded-kbd-iso2022-invocations 2 nil)
152    (vector (if (= (charset-dimension charset) 1)
153		(make-char charset char)
154	      (make-char charset char (read-char-exclusive))))))
155
156(defun encoded-kbd-self-insert-sjis (ignore)
157  (let ((char (encoded-kbd-last-key)))
158    (vector
159     (if (or (< char ?\xA0) (>= char ?\xE0))
160	 (decode-sjis-char (+ (ash char 8) (read-char-exclusive)))
161       (make-char 'katakana-jisx0201 char)))))
162
163(defun encoded-kbd-self-insert-big5 (ignore)
164  (let ((char (encoded-kbd-last-key)))
165    (vector
166     (decode-big5-char (+ (ash char 8) (read-char-exclusive))))))
167
168(defun encoded-kbd-self-insert-ccl (ignore)
169  (let ((str (char-to-string (encoded-kbd-last-key)))
170	(ccl (car (aref (coding-system-spec (keyboard-coding-system)) 4)))
171	(vec [nil nil nil nil nil nil nil nil nil])
172	result)
173    (while (= (length (setq result (ccl-execute-on-string ccl vec str t))) 0)
174      (dotimes (i 9) (aset vec i nil))
175      (setq str (format "%s%c" str (read-char-exclusive))))
176    (vector (aref result 0))))
177
178(defun encoded-kbd-setup-keymap (coding)
179  ;; At first, reset the keymap.
180  (define-key encoded-kbd-mode-map "\e" nil)
181  ;; Then setup the keymap according to the keyboard coding system.
182  (cond
183   ((eq (coding-system-type coding) 1)	; SJIS
184    (let ((i 128))
185      (while (< i 256)
186	(define-key key-translation-map
187	  (vector i) 'encoded-kbd-self-insert-sjis)
188	(setq i (1+ i))))
189    8)
190
191   ((eq (coding-system-type coding) 3)	; Big5
192    (let ((i 161))
193      (while (< i 255)
194	(define-key key-translation-map
195	  (vector i) 'encoded-kbd-self-insert-big5)
196	(setq i (1+ i))))
197    8)
198
199   ((eq (coding-system-type coding) 2) ; ISO-2022
200    (let ((flags (coding-system-flags coding))
201	  use-designation)
202      (if (aref flags 8)
203	  nil				; Don't support locking-shift.
204	(setq encoded-kbd-iso2022-designations (make-vector 4 nil)
205	      encoded-kbd-iso2022-invocations (make-vector 3 nil))
206	(dotimes (i 4)
207	  (if (aref flags i)
208	      (if (charsetp (aref flags i))
209		  (aset encoded-kbd-iso2022-designations
210			i (aref flags i))
211		(setq use-designation t)
212		(if (charsetp (car-safe (aref flags i)))
213		    (aset encoded-kbd-iso2022-designations
214			  i (car (aref flags i)))))))
215	(aset encoded-kbd-iso2022-invocations 0 0)
216	(if (aref encoded-kbd-iso2022-designations 1)
217	    (aset encoded-kbd-iso2022-invocations 1 1))
218	(when use-designation
219	  (define-key encoded-kbd-mode-map "\e" 'encoded-kbd-iso2022-esc-prefix)
220	  (define-key key-translation-map "\e" 'encoded-kbd-iso2022-esc-prefix))
221	(when (or (aref flags 2) (aref flags 3))
222	  (define-key key-translation-map
223	    [?\216] 'encoded-kbd-iso2022-single-shift)
224	  (define-key key-translation-map
225	    [?\217] 'encoded-kbd-iso2022-single-shift))
226	(or (eq (aref flags 0) 'ascii)
227	    (dotimes (i 96)
228	      (define-key key-translation-map
229		(vector (+ 32 i)) 'encoded-kbd-self-insert-iso2022-7bit)))
230	(if (aref flags 7)
231	    t
232	  (dotimes (i 96)
233	    (define-key key-translation-map
234	      (vector (+ 160 i)) 'encoded-kbd-self-insert-iso2022-8bit))
235	  8))))
236
237   ((eq (coding-system-type coding) 4)	; CCL-base
238    (let ((valid-codes (or (coding-system-get coding 'valid-codes)
239			   '((128 . 255))))
240	  elt from to valid)
241      (while valid-codes
242	(setq elt (car valid-codes) valid-codes (cdr valid-codes))
243	(if (consp elt)
244	    (setq from (car elt) to (cdr elt))
245	  (setq from (setq to elt)))
246	(while (<= from to)
247	  (if (>= from 128)
248	      (define-key key-translation-map
249		(vector from) 'encoded-kbd-self-insert-ccl))
250	  (setq from (1+ from))))
251      8))
252
253   (t
254    nil)))
255
256;; key-translation-map at the time Encoded-kbd mode is turned on is
257;; saved here.
258(defvar saved-key-translation-map nil)
259
260;; Input mode at the time Encoded-kbd mode is turned on is saved here.
261(defvar saved-input-mode nil)
262
263(put 'encoded-kbd-mode 'permanent-local t)
264;;;###autoload
265(define-minor-mode encoded-kbd-mode
266  "Toggle Encoded-kbd minor mode.
267With arg, turn Encoded-kbd mode on if and only if arg is positive.
268
269You should not turn this mode on manually, instead use the command
270\\[set-keyboard-coding-system] which turns on or off this mode
271automatically.
272
273In Encoded-kbd mode, a text sent from keyboard is accepted
274as a multilingual text encoded in a coding system set by
275\\[set-keyboard-coding-system]."
276  :global t :group 'keyboard :group 'mule
277
278  (if encoded-kbd-mode
279      ;; We are turning on Encoded-kbd mode.
280      (let ((coding (keyboard-coding-system))
281	    result)
282	(or saved-key-translation-map
283	    (if (keymapp key-translation-map)
284		(setq saved-key-translation-map
285		      (copy-keymap key-translation-map))
286	      (setq key-translation-map (make-sparse-keymap))))
287	(or saved-input-mode
288	    (setq saved-input-mode
289		  (current-input-mode)))
290	(setq result (and coding (encoded-kbd-setup-keymap coding)))
291	(if result
292	    (if (eq result 8)
293		(set-input-mode
294		 (nth 0 saved-input-mode)
295		 (nth 1 saved-input-mode)
296		 'use-8th-bit
297		 (nth 3 saved-input-mode)))
298	  (setq encoded-kbd-mode nil
299		saved-key-translation-map nil
300		saved-input-mode nil)
301	  (error "Unsupported coding system in Encoded-kbd mode: %S"
302		 coding)))
303
304    ;; We are turning off Encoded-kbd mode.
305    (setq key-translation-map saved-key-translation-map
306	  saved-key-translation-map nil)
307    (apply 'set-input-mode saved-input-mode)
308    (setq saved-input-mode nil)))
309
310(provide 'encoded-kb)
311
312;;; arch-tag: 76f0f9b3-65e7-45c3-b692-59509a87ad44
313;;; encoded-kb.el ends here
314