;;; vietnamese.el --- Support for Vietnamese

;; Copyright (C) 1995 Electrotechnical Laboratory, JAPAN.
;; Licensed to the Free Software Foundation.
;; Copyright (C) 1997 MORIOKA Tomohiko

;; Keywords: multilingual, Vietnamese

;; This file is part of XEmacs.

;; XEmacs 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 2, or (at your option)
;; any later version.

;; XEmacs 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 XEmacs; see the file COPYING.  If not, write to the Free
;; Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
;; 02111-1307, USA.

;;; Commentary:

;; For Vietnames, the character sets VISCII and VSCII are supported.

;;; Code:

(eval-when-compile

(defvar viet-viscii-decode-table
  [;; VISCII is a full 8-bit code.
   0 1 ?,2F(B 3 4 ?,2G(B ?,2g(B 7 8 9 10 11 12 13 14 15
   16 17 18 19 ?,2V(B 21 22 23 24 ?,2[(B 26 27 28 29 ?,2\(B 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 
   ?,2U(B ?,2!(B ?,2"(B ?,2#(B ?,2$(B ?,2%(B ?,2&(B ?,2'(B ?,2((B ?,2)(B ?,2*(B ?,2+(B ?,2,(B ?,2-(B ?,2.(B ?,2/(B
   ?,20(B ?,21(B ?,22(B ?,25(B ?,2~(B ?,2>(B ?,26(B ?,27(B ?,28(B ?,2v(B ?,2w(B ?,2o(B ?,2|(B ?,2{(B ?,2x(B ?,2O(B
   ?,2u(B ?,1!(B ?,1"(B ?,1#(B ?,1$(B ?,1%(B ?,1&(B ?,1'(B ?,1((B ?,1)(B ?,1*(B ?,1+(B ?,1,(B ?,1-(B ?,1.(B ?,1/(B
   ?,10(B ?,11(B ?,12(B ?,2^(B ?,2=(B ?,15(B ?,16(B ?,17(B ?,18(B ?,2q(B ?,2Q(B ?,2W(B ?,2X(B ?,1=(B ?,1>(B ?,2_(B
   ?,2`(B ?,2a(B ?,2b(B ?,2c(B ?,2d(B ?,2e(B ?,1F(B ?,1G(B ?,2h(B ?,2i(B ?,2j(B ?,2k(B ?,2l(B ?,2m(B ?,2n(B ?,1O(B
   ?,2p(B ?,1Q(B ?,2r(B ?,2s(B ?,2t(B ?,1U(B ?,1V(B ?,1W(B ?,1X(B ?,2y(B ?,2z(B ?,1[(B ?,1\(B ?,2}(B ?,1^(B ?,1_(B
   ?,1`(B ?,1a(B ?,1b(B ?,1c(B ?,1d(B ?,1e(B ?,1f(B ?,1g(B ?,1h(B ?,1i(B ?,1j(B ?,1k(B ?,1l(B ?,1m(B ?,1n(B ?,1o(B
   ?,1p(B ?,1q(B ?,1r(B ?,1s(B ?,1t(B ?,1u(B ?,1v(B ?,1w(B ?,1x(B ?,1y(B ?,1z(B ?,1{(B ?,1|(B ?,1}(B ?,1~(B ?,2f(B ]
  "Vietnamese VISCII encoding table.")

(defvar viet-viscii-encode-table
  (let ((table-lower (make-vector 128 0))
	(table-upper (make-vector 128 0))
	(i 0)
	char-component)
    (while (< i 256)
      (setq char-component (split-char (aref viet-viscii-decode-table i)))
      (cond ((eq (car char-component) 'vietnamese-viscii-lower)
	     (aset table-lower (nth 1 char-component) i))
	    ((eq (car char-component) 'vietnamese-viscii-upper)
	     (aset table-upper (nth 1 char-component) i)))
      (setq i (1+ i)))
    (cons table-lower table-upper))
  "Vietnamese VISCII decoding table.
Cons of tables for decoding lower-case chars and upper-case characterss.
Both tables are indexed by the position code of Vietnamese characters.")

(defvar viet-vscii-decode-table
  [;; VSCII is a full 8-bit code.
   0 ?,2z(B ?,2x(B 3 ?,2W(B ?,2X(B ?,2f(B 7 8 9 10 11 12 13 14 15
   16 ?,2Q(B ?,2_(B ?,2O(B ?,2V(B ?,2[(B ?,2}(B ?,2\(B 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 
   ?,2`(B ?,2d(B ?,2c(B ?,2a(B ?,2U(B ?,2#(B ?,2'(B ?,2h(B ?,2k(B ?,2((B ?,2i(B ?,2)(B ?,2.(B ?,2l(B ?,2o(B ?,2n(B
   ?,2m(B ?,28(B ?,2r(B ?,2v(B ?,2u(B ?,2s(B ?,2w(B ?,25(B ?,26(B ?,27(B ?,2^(B ?,2>(B ?,2~(B ?,2y(B ?,2|(B ?,2{(B
   160 ?,2e(B ?,2b(B ?,2j(B ?,2t(B ?,2=(B ?,2_(B ?,2p(B ?,1e(B ?,1b(B ?,1j(B ?,1t(B ?,1>(B ?,1y(B ?,1p(B ?,2"(B
   192 193 194 195 196 ?,1`(B ?,1d(B ?,1c(B ?,1a(B ?,1U(B ?,2F(B ?,1"(B ?,1F(B ?,1G(B ?,1!(B ?,2G(B
   ?,2!(B ?,2%(B ?,2&(B ?,2g(B ?,2%(B ?,2+(B ?,1#(B ?,1%(B ?,1&(B ?,1g(B ?,1$(B ?,1'(B ?,1h(B ?,2,(B ?,1k(B ?,1((B
   ?,1i(B ?,1)(B ?,1+(B ?,1,(B ?,1-(B ?,1*(B ?,1.(B ?,1l(B ?,1o(B ?,2-(B ?,2*(B ?,20(B ?,1n(B ?,1m(B ?,18(B ?,1r(B
   ?,21(B ?,1v(B ?,1u(B ?,1s(B ?,1w(B ?,10(B ?,11(B ?,12(B ?,1/(B ?,15(B ?,16(B ?,17(B ?,1^(B ?,1>(B ?,1~(B ?,1y(B
   ?,22(B ?,1|(B ?,1{(B ?,1z(B ?,1x(B ?,1W(B ?,1X(B ?,1f(B ?,1Q(B ?,1q(B ?,1O(B ?,1V(B ?,1[(B ?,1}(B ?,1\(B ?,2/(B]
  "Vietnamese VSCII code table.")

(defvar viet-vscii-encode-table
  (let ((table-lower (make-vector 128 0))
	(table-upper (make-vector 128 0))
	(i 0)
	char-component)
    (while (< i 256)
      (setq char-component (split-char (aref viet-vscii-decode-table i)))
      (cond ((eq (car char-component) 'vietnamese-viscii-lower)
	     (aset table-lower (nth 1 char-component) i))
	    ((eq (car char-component) 'vietnamese-viscii-upper)
	     (aset table-upper (nth 1 char-component) i)))
      (setq i (1+ i)))
    (cons table-lower table-upper))
  "Vietnamese VSCII decoding table.
Cons of tables for decoding lower-case chars and upper-case characterss.
Both tables are indexed by the position code of Vietnamese characters.")

)

(define-ccl-program ccl-read-viscii
  `(3
    ((read r0)
     (loop
       (write-read-repeat r0 ,viet-viscii-decode-table))
     ))
  "CCL program to read VISCII 1.1")

;; (define-ccl-program ccl-decode-viscii
;;   `(3
;;     ((read r0)
;;      (loop
;;       (write-read-repeat r0 ,viet-viscii-decode-table))
;;      ))
;;   "CCL program to decode VISCII 1.1")

;; Multibyte form of a Vietnamese character is as follows (3-byte):
;;   LEADING-CODE-PRIVATE-11 LEADING-CODE-EXTENDED-11 POSITION-CODE
;; where LEADING-CODE-EXTENDED-11 for Vietnamese is
;; `vietnamese-viscii-lower' or `vietnamese-viscii-upper'.

(define-ccl-program ccl-write-viscii
  `(1
    ((read r0)
     (loop
       (if (r0 < 128)
	   ;; ASCII
	   (write-read-repeat r0)
	 ;; not ASCII
	 (if (r0 != ,leading-code-private-11)
	     ;; not Vietnamese
	     (write-read-repeat r0)
	   ((read-if (r0 == ,(charset-id 'vietnamese-viscii-lower))
	     (;; Vietnamese lower
	      (read r0)
	      (r0 -= 128)
	      (write-read-repeat r0 ,(car viet-viscii-encode-table))
	      (if (r0 == ,(charset-id 'vietnamese-viscii-upper))
		  (;; Vietnamese upper
		   (read r0)
		   (r0 -= 128)
		   (write-read-repeat r0 ,(cdr viet-viscii-encode-table)))
	        ;; not Vietnamese
		(write-read-repeat r0))))))))))
  "CCL program to write VISCII 1.1")

(define-ccl-program ccl-encode-viscii-font
  `(0
    ;; In:  R0:vietnamese-viscii-lower/vietnamese-viscii-upper
    ;;      R1:position code
    ;; Out: R1:font code point
    (if (r0 == ,(charset-id 'vietnamese-viscii-lower))
        (r1 = r1 ,(car viet-viscii-encode-table))
      (r1 = r1 ,(cdr viet-viscii-encode-table)))
    )
  "CCL program to encode Vietnamese chars to VISCII 1.1 font")

(define-ccl-program ccl-decode-vscii
  `(3
    ((read r0)
     (loop
      (write-read-repeat r0 ,viet-vscii-decode-table))
     ))
  "CCL program to decode VSCII-1.")

(define-ccl-program ccl-encode-vscii
  `(1
    ((read r0)
     (loop
      (if (r0 < 128)
          ;; ASCII
          (write-read-repeat r0)
        ;; not ASCII 
        (if (r0 != ,leading-code-private-11)
             ;; not Vietnamese
            (write-read-repeat r0)
          (read-if (r0 == ,(charset-id 'vietnamese-viscii-lower))
                   (;; Vietnamese lower
                    (read r0)
                    (r0 -= 128)
                    (write-read-repeat r0 ,(car viet-vscii-encode-table)))
                   (if (r0 == ,(charset-id 'vietnamese-viscii-upper))
                       (;; Vietnamese upper
                        (read r0)
                        (r0 -= 128)
                        (write-read-repeat r0 ,(cdr viet-viscii-encode-table)))
                     ;; not Vietnamese
                     (write-read-repeat r0))))))))
  "CCL program to encode VSCII-1.")
(define-ccl-program ccl-encode-vscii-font
  `(0
    ;; In:  R0:vietnamese-viscii-lower/vietnamese-viscii-upper
    ;;      R1:position code
    ;; Out: R1:font code point
    (if (r0 == ,(charset-id 'vietnamese-viscii-lower))
        (r1 = r1 ,(car viet-vscii-encode-table))
      (r1 = r1 ,(cdr viet-vscii-encode-table)))
    )
  "CCL program to encode Vietnamese chars to VSCII-1 font.")


(make-coding-system
 'viscii 'ccl
 "Coding-system used for VISCII 1.1."
 `(mnemonic "VISCII"
   decode ,ccl-decode-viscii
   encode ,ccl-encode-viscii))

;; (make-coding-system
;;  'vietnamese-viscii 4 ?V
;;  "8-bit encoding for Vietnamese VISCII 1.1 (MIME:VISCII)"
;;  (cons ccl-decode-viscii ccl-encode-viscii))

;; (define-coding-system-alias 'viscii 'vietnamese-viscii)

(make-coding-system
 'vscii 'ccl
 "Coding-system used for VSCII 1.1."
 `(mnemonic "VSCII"
   decode ,ccl-encode-vscii
   encode ,ccl-decode-vscii))

;; (make-coding-system
;;  'vietnamese-vscii 4 ?v
;;  "8-bit encoding for Vietnamese VSCII-1"
;;  (cons ccl-decode-vscii ccl-encode-vscii))

;; (define-coding-system-alias 'vscii 'vietnamese-vscii)

(make-coding-system
 'viqr 'no-conversion
 "Coding-system used for VIQR."
 '(mnemonic "VIQR"
   eol-type lf
   post-read-conversion viqr-post-read-conversion
   pre-write-conversion viqr-pre-write-conversion))

;; (make-coding-system
;;  'vietnamese-viqr 0 ?q
;;  "Vietnamese latin transcription (VIQR)"
;;  nil)
;; (put 'vietnamese-viqr 'post-read-conversion 'viqr-post-read-conversion)
;; (put 'vietnamese-viqr 'pre-write-conversion 'viqr-pre-write-conversion)

;; (define-coding-system-alias 'viqr 'vietnamese-viqr)

;; For VISCII users
(set-charset-ccl-program 'vietnamese-viscii-lower
			 ccl-encode-viscii-font)
(set-charset-ccl-program 'vietnamese-viscii-upper
			 ccl-encode-viscii-font)
;; For VSCII users
(set-charset-ccl-program 'vietnamese-lower ccl-encode-vscii-font)
(set-charset-ccl-program 'vietnamese-upper ccl-encode-vscii-font)

;; (setq font-ccl-encoder-alist
;;       (cons (cons "viscii" ccl-encode-viscii-font) font-ccl-encoder-alist))

;; (setq font-ccl-encoder-alist
;;       (cons (cons "vscii" ccl-encode-vscii-font) font-ccl-encoder-alist))

(set-language-info-alist
 "Vietnamese" '((setup-function . setup-vietnamese-environment)
		(charset . (vietnamese-viscii-lower
			    vietnamese-viscii-upper))
		(coding-system . (viscii vscii viqr))
		(sample-text . "Vietnamese (Ti,1*(Bng Vi,1.(Bt)	Ch,1`(Bo b,1U(Bn")
		(documentation . "\
For Vietnamese, Emacs uses special charasets internally.
They can be decoded from and encoded to VISCC, VSCII, and VIQR.")
		))

;;; vietnamese.el ends here