lisp/language/thai-util.el

   1 ;;; thai-util.el --- utilities for Thai -*- coding: utf-8; -*-
   2
   3 ;; Copyright (C) 2000-2014 Free Software Foundation, Inc.
   4 ;; Copyright (C) 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004,
   5 ;;   2005, 2006, 2007, 2008, 2009, 2010, 2011
   6 ;;   National Institute of Advanced Industrial Science and Technology (AIST)
   7 ;;   Registration Number H14PRO021
   8
   9 ;; Keywords: mule, multilingual, Thai, i18n
  10
  11 ;; This file is part of GNU Emacs.
  12
  13 ;; GNU Emacs is free software: you can redistribute it and/or modify
  14 ;; it under the terms of the GNU General Public License as published by
  15 ;; the Free Software Foundation, either version 3 of the License, or
  16 ;; (at your option) any later version.
  17
  18 ;; GNU Emacs is distributed in the hope that it will be useful,
  19 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  20 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21 ;; GNU General Public License for more details.
  22
  23 ;; You should have received a copy of the GNU General Public License
  24 ;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
  25
  26 ;;; Commentary:
  27
  28 ;;; Code:
  29
  30 (defvar thai-auto-composition-mode)
  31
  32 ;; Setting information of Thai characters.
  33
  34 (defconst thai-category-table (make-category-table))
  35 (define-category ?c "Thai consonant" thai-category-table)
  36 (define-category ?v "Thai upper/lower vowel" thai-category-table)
  37 (define-category ?t "Thai tone mark" thai-category-table)
  38 (define-category ?u "Thai tone mark and upper sign" thai-category-table)
  39 (define-category ?I "THAI CHARACTER SARA I" thai-category-table)
  40 (define-category ?U "THAI CHARACTER THANTHAKHAT" thai-category-table)
  41
  42 ;; The general composing rules are as follows:
  43 ;;
  44 ;;                          T
  45 ;;       V        U         V                  U
  46 ;; CV -> C, CU -> C, CVT -> C, Cv -> C, CvU -> C
  47 ;;                                   v         v
  48 ;;
  49 ;; where C: consonant, V: vowel upper, v: vowel lower,
  50 ;;       T: tone mark, U: tone mark and upper sign.
  51 ;; Special rule: The sign `์' can be put on the vowel `ิ'.
  52
  53
  54 (defvar thai-composition-pattern
  55   "\\cc\\(\\cu\\|\\cI\\cU\\|\\cv\\ct?\\)\\|\\cv\\ct\\|\\cI\\cU"
  56   "Regular expression matching a Thai composite sequence.")
  57
  58 (let ((l '((?ก consonant "LETTER KO KAI")                             ; 0xA1
  59            (?ข consonant "LETTER KHO KHAI")                           ; 0xA2
  60            (?ฃ consonant "LETTER KHO KHUAT")                          ; 0xA3
  61            (?ค consonant "LETTER KHO KHWAI")                          ; 0xA4
  62            (?ฅ consonant "LETTER KHO KHON")                           ; 0xA5
  63            (?ฆ consonant "LETTER KHO RAKHANG")                                ; 0xA6
  64            (?ง consonant "LETTER NGO NGU")                            ; 0xA7
  65            (?จ consonant "LETTER CHO CHAN")                           ; 0xA8
  66            (?ฉ consonant "LETTER CHO CHING")                          ; 0xA9
  67            (?ช consonant "LETTER CHO CHANG")                          ; 0xAA
  68            (?ซ consonant "LETTER SO SO")                              ; 0xAB
  69            (?ฌ consonant "LETTER CHO CHOE")                           ; 0xAC
  70            (?ญ consonant "LETTER YO YING")                            ; 0xAD
  71            (?ฎ consonant "LETTER DO CHADA")                           ; 0xAE
  72            (?ฏ consonant "LETTER TO PATAK")                           ; 0xAF
  73            (?ฐ consonant "LETTER THO THAN")                           ; 0xB0
  74            (?ฑ consonant "LETTER THO NANGMONTHO")                     ; 0xB1
  75            (?ฒ consonant "LETTER THO PHUTHAO")                                ; 0xB2
  76            (?ณ consonant "LETTER NO NEN")                             ; 0xB3
  77            (?ด consonant "LETTER DO DEK")                             ; 0xB4
  78            (?ต consonant "LETTER TO TAO")                             ; 0xB5
  79            (?ถ consonant "LETTER THO THUNG")                          ; 0xB6
  80            (?ท consonant "LETTER THO THAHAN")                         ; 0xB7
  81            (?ธ consonant "LETTER THO THONG")                          ; 0xB8
  82            (?น consonant "LETTER NO NU")                              ; 0xB9
  83            (?บ consonant "LETTER BO BAIMAI")                          ; 0xBA
  84            (?ป consonant "LETTER PO PLA")                             ; 0xBB
  85            (?ผ consonant "LETTER PHO PHUNG")                          ; 0xBC
  86            (?ฝ consonant "LETTER FO FA")                              ; 0xBD
  87            (?พ consonant "LETTER PHO PHAN")                           ; 0xBE
  88            (?ฟ consonant "LETTER FO FAN")                             ; 0xBF
  89            (?ภ consonant "LETTER PHO SAMPHAO")                                ; 0xC0
  90            (?ม consonant "LETTER MO MA")                              ; 0xC1
  91            (?ย consonant "LETTER YO YAK")                             ; 0xC2
  92            (?ร consonant "LETTER RO RUA")                             ; 0xC3
  93            (?ฤ vowel-base "LETTER RU (Pali vowel letter)")            ; 0xC4
  94            (?ล consonant "LETTER LO LING")                            ; 0xC5
  95            (?ฦ vowel-base "LETTER LU (Pali vowel letter)")            ; 0xC6
  96            (?ว consonant "LETTER WO WAEN")                            ; 0xC7
  97            (?ศ consonant "LETTER SO SALA")                            ; 0xC8
  98            (?ษ consonant "LETTER SO RUSI")                            ; 0xC9
  99            (?ส consonant "LETTER SO SUA")                             ; 0xCA
 100            (?ห consonant "LETTER HO HIP")                             ; 0xCB
 101            (?ฬ consonant "LETTER LO CHULA")                           ; 0xCC
 102            (?อ consonant "LETTER O ANG")                              ; 0xCD
 103            (?ฮ consonant "LETTER HO NOK HUK")                         ; 0xCE
 104            (?ฯ special "PAI YAN NOI (abbreviation)")                  ; 0xCF
 105            (?ะ vowel-base "VOWEL SIGN SARA A")                                ; 0xD0
 106            (?ั vowel-upper "VOWEL SIGN MAI HAN-AKAT N/S-T")           ; 0xD1
 107            (?า vowel-base "VOWEL SIGN SARA AA")                               ; 0xD2
 108            (?ำ vowel-base "VOWEL SIGN SARA AM")                               ; 0xD3
 109            (?ิ vowel-upper "VOWEL SIGN SARA I N/S-T")                 ; 0xD4
 110            (?ี vowel-upper "VOWEL SIGN SARA II N/S-T")                        ; 0xD5
 111            (?ึ vowel-upper "VOWEL SIGN SARA UE N/S-T")                        ; 0xD6
 112            (?ื vowel-upper "VOWEL SIGN SARA UEE N/S-T")                       ; 0xD7
 113            (?ุ vowel-lower "VOWEL SIGN SARA U N/S-B")                 ; 0xD8
 114            (?ู vowel-lower "VOWEL SIGN SARA UU N/S-B")                        ; 0xD9
 115            (?ฺ vowel-lower "VOWEL SIGN PHINTHU N/S-B (Pali virama)")  ; 0xDA
 116            (?฻ invalid nil)                                           ; 0xDA
 117            (?฼ invalid nil)                                           ; 0xDC
 118            (?฽ invalid nil)                                           ; 0xDC
 119            (?฾ invalid nil)                                           ; 0xDC
 120            (?฿ special "BAHT SIGN (currency symbol)")                 ; 0xDF
 121            (?เ vowel-base "VOWEL SIGN SARA E")                                ; 0xE0
 122            (?แ vowel-base "VOWEL SIGN SARA AE")                               ; 0xE1
 123            (?โ vowel-base "VOWEL SIGN SARA O")                                ; 0xE2
 124            (?ใ vowel-base "VOWEL SIGN SARA MAI MUAN")                 ; 0xE3
 125            (?ไ vowel-base "VOWEL SIGN SARA MAI MALAI")                        ; 0xE4
 126            (?ๅ vowel-base "LAK KHANG YAO")                            ; 0xE5
 127            (?ๆ special "MAI YAMOK (repetition)")                      ; 0xE6
 128            (?็ sign-upper "VOWEL SIGN MAI TAI KHU N/S-T")             ; 0xE7
 129            (?่ tone "TONE MAI EK N/S-T")                              ; 0xE8
 130            (?้ tone "TONE MAI THO N/S-T")                             ; 0xE9
 131            (?๊ tone "TONE MAI TRI N/S-T")                             ; 0xEA
 132            (?๋ tone "TONE MAI CHATTAWA N/S-T")                                ; 0xEB
 133            (?์ sign-upper "THANTHAKHAT N/S-T (cancellation mark)")    ; 0xEC
 134            (?ํ sign-upper "NIKKHAHIT N/S-T (final nasal)")            ; 0xED
 135            (?๎ sign-upper "YAMAKKAN N/S-T")                           ; 0xEE
 136            (?๏ special "FONRMAN")                                     ; 0xEF
 137            (?๐ special "DIGIT ZERO")                                  ; 0xF0
 138            (?๑ special "DIGIT ONE")                                   ; 0xF1
 139            (?๒ special "DIGIT TWO")                                   ; 0xF2
 140            (?๓ special "DIGIT THREE")                                 ; 0xF3
 141            (?๔ special "DIGIT FOUR")                                  ; 0xF4
 142            (?๕ special "DIGIT FIVE")                                  ; 0xF5
 143            (?๖ special "DIGIT SIX")                                   ; 0xF6
 144            (?๗ special "DIGIT SEVEN")                                 ; 0xF7
 145            (?๘ special "DIGIT EIGHT")                                 ; 0xF8
 146            (?๙ special "DIGIT NINE")                                  ; 0xF9
 147            (?๚ special "ANGKHANKHU (ellipsis)")                               ; 0xFA
 148            (?๛ special "KHOMUT (beginning of religious texts)")               ; 0xFB
 149            (?๜ invalid nil)                                           ; 0xFC
 150            (?๝ invalid nil)                                           ; 0xFD
 151            (?๞ invalid nil)                                           ; 0xFE
 152            ))
 153       elm)
 154   (while l
 155     (setq elm (car l) l (cdr l))
 156     (let ((char (car elm))
 157           (ptype (nth 1 elm)))
 158       (put-char-code-property char 'phonetic-type ptype)
 159       (cond ((eq ptype 'consonant)
 160              (modify-category-entry char ?c thai-category-table))
 161             ((memq ptype '(vowel-upper vowel-lower))
 162              (modify-category-entry char ?v thai-category-table)
 163              (if (= char ?ิ)
 164                  ;; Give category `I' to "SARA I".
 165                  (modify-category-entry char ?I thai-category-table)))
 166             ((eq ptype 'tone)
 167              (modify-category-entry char ?t thai-category-table)
 168              (modify-category-entry char ?u thai-category-table))
 169             ((eq ptype 'sign-upper)
 170              (modify-category-entry char ?u thai-category-table)
 171              (if (= char ?์)
 172                  ;; Give category `U' to "THANTHAKHAT".
 173                  (modify-category-entry char ?U thai-category-table))))
 174       (put-char-code-property char 'name (nth 2 elm)))))
 175
 176 (defun thai-compose-syllable (beg end &optional category-set string)
 177   (or category-set
 178       (setq category-set
 179             (char-category-set (if string (aref string beg) (char-after beg)))))
 180   (if (aref category-set ?c)
 181       ;; Starting with a consonant.  We do relative composition.
 182       (if string
 183           (compose-string string beg end)
 184         (compose-region beg end))
 185     ;; Vowel tone sequence.
 186     (if string
 187         (compose-string string beg end (list (aref string beg) '(Bc . Bc)
 188                                              (aref string (1+ beg))))
 189       (compose-region beg end (list (char-after beg) '(Bc . Bc)
 190                                     (char-after (1+ beg))))))
 191   (- end beg))
 192
 193 ;;;###autoload
 194 (defun thai-compose-region (beg end)
 195   "Compose Thai characters in the region.
 196 When called from a program, expects two arguments,
 197 positions (integers or markers) specifying the region."
 198   (interactive "r")
 199   (let ((pos (point)))
 200     (save-restriction
 201       (narrow-to-region beg end)
 202       (goto-char (point-min))
 203       (with-category-table thai-category-table
 204         (while (re-search-forward thai-composition-pattern nil t)
 205           (setq beg (match-beginning 0) end (match-end 0))
 206           (if (and (> pos beg) (< pos end))
 207               (setq pos end))
 208           (thai-compose-syllable beg end
 209                                  (char-category-set (char-after beg))))))
 210     (goto-char pos)))
 211
 212 ;;;###autoload
 213 (defun thai-compose-string (string)
 214   "Compose Thai characters in STRING and return the resulting string."
 215   (with-category-table thai-category-table
 216     (let ((idx 0))
 217       (while (setq idx (string-match thai-composition-pattern string idx))
 218         (thai-compose-syllable idx (match-end 0) nil string)
 219         (setq idx (match-end 0)))))
 220   string)
 221
 222 ;;;###autoload
 223 (defun thai-compose-buffer ()
 224   "Compose Thai characters in the current buffer."
 225   (interactive)
 226   (thai-compose-region (point-min) (point-max)))
 227
 228 ;;;###autoload
 229 (defun thai-composition-function (gstring)
 230   (if (= (lgstring-char-len gstring) 1)
 231       (compose-gstring-for-graphic gstring)
 232     (or (font-shape-gstring gstring)
 233         (let ((glyph-len (lgstring-glyph-len gstring))
 234               (last-char (lgstring-char gstring
 235                                         (1- (lgstring-char-len gstring))))
 236               (i 0)
 237               glyph)
 238           (while (and (< i glyph-len)
 239                       (setq glyph (lgstring-glyph gstring i)))
 240             (setq i (1+ i)))
 241           (if (= last-char ?ำ)
 242               (setq i (1- i)))
 243           (compose-glyph-string-relative gstring 0 i 0.1)))))
 244
 245 ;; Thai-word-mode requires functions in the feature `thai-word'.
 246 (require 'thai-word)
 247
 248 (defvar thai-word-mode-map
 249   (let ((map (make-sparse-keymap)))
 250     (define-key map [remap forward-word] 'thai-forward-word)
 251     (define-key map [remap backward-word] 'thai-backward-word)
 252     (define-key map [remap kill-word] 'thai-kill-word)
 253     (define-key map [remap backward-kill-word] 'thai-backward-kill-word)
 254     (define-key map [remap transpose-words] 'thai-transpose-words)
 255     map)
 256   "Keymap for `thai-word-mode'.")
 257
 258 (define-minor-mode thai-word-mode
 259   "Minor mode to make word-oriented commands aware of Thai words.
 260 With a prefix argument ARG, enable the mode if ARG is positive,
 261 and disable it otherwise.  If called from Lisp, enable the mode
 262 if ARG is omitted or nil.  The commands affected are
 263 \\[forward-word], \\[backward-word], \\[kill-word], \\[backward-kill-word],
 264 \\[transpose-words], and \\[fill-paragraph]."
 265   :global t :group 'mule
 266   (cond (thai-word-mode
 267          ;; This enables linebreak between Thai characters.
 268          (modify-category-entry (make-char 'thai-tis620) ?|)
 269          ;; This enables linebreak at a Thai word boundary.
 270          (put-charset-property 'thai-tis620 'fill-find-break-point-function
 271                                'thai-fill-find-break-point))
 272         (t
 273          (modify-category-entry (make-char 'thai-tis620) ?| nil t)
 274          (put-charset-property 'thai-tis620 'fill-find-break-point-function
 275                                nil))))
 276
 277 ;; Function to call on entering the Thai language environment.
 278 (defun setup-thai-language-environment-internal ()
 279   (thai-word-mode 1))
 280
 281 ;; Function to call on exiting the Thai language environment.
 282 (defun exit-thai-language-environment-internal ()
 283   (thai-word-mode -1))
 284
 285 ;;
 286 (provide 'thai-util)
 287
 288 ;;; thai-util.el ends here