intl/lwbrk/rulebrk.c

   1 /* This Source Code Form is subject to the terms of the Mozilla Public
   2  * License, v. 2.0. If a copy of the MPL was not distributed with this
   3  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   4 #define TH_UNICODE
   5
   6 #include <stdlib.h>
   7 #include <assert.h>
   8 #include "th_char.h"
   9 #define th_isalpha(c)   (((c)>='a'&&(c)<='z')||((c)>='A'&&(c)<='Z'))
  10 #define th_isspace(c)   ((c)==' '||(c)=='\t')
  11
  12
  13 /*
  14 /////////////////////////////////////////////////
  15 // Thai character type array
  16 */
  17
  18 typedef unsigned short twb_t;
  19 extern const twb_t _TwbType[0x100-0xa0];
  20
  21 /*
  22 // bit definition
  23 */
  24
  25 #define VRS 0x0001
  26 #define VRE 0x0002
  27 #define VRX 0x0004
  28
  29 #define VRA 0x0008
  30
  31 #define VLA 0x0010
  32 #define VLO 0x0020
  33 #define VLI 0x0040
  34
  35 #define VC 0x0080
  36
  37 #define CC 0x0100
  38 #define CS 0x0200
  39
  40 #define C2 0x0400
  41 #define CHB 0x0800
  42 #define CHE 0x1000
  43
  44 #define MT 0x2000
  45 /*
  46 //_#define me 0x2000
  47 */
  48 #define M 0x4000
  49
  50 #define T 0x8000
  51
  52 #define VL      (VLA|VLO|VLI)
  53 #define VR      (VRS|VRE|VRX)
  54 #define NE      (VL|VRS)
  55 #define NB      (VR|M)
  56 #define V       (VL|VR)
  57 #define CX      (CC|CS)
  58 #define C       (CX|VC)
  59 #define A (C|V|M)
  60
  61 #define twbtype(c)      (_TwbType[th_zcode(c)])
  62
  63 #ifndef TRUE
  64 #define TRUE 1
  65 #define FALSE 0
  66 #endif
  67 #define RETURN(b) return (b)
  68
  69
  70 /*
  71 /////////////////////////////////////////////////
  72 */
  73
  74 int TrbWordBreakPos(const th_char *pstr, int left,
  75                     const th_char *rstr, int right)
  76 /*                 const ThBreakIterator *it, const th_char **p)*/
  77 {
  78         /*
  79         //int left, right;
  80         //const th_char *s = *p;
  81         */
  82     const th_char *lstr = pstr + left;
  83         th_char _c[6];
  84         twb_t _t[6];
  85         #define c(i) (_c[(i)+3])
  86         #define t(i) (_t[(i)+3])
  87         int i, j;
  88
  89         /*
  90         //left = s - it->begin;
  91         */
  92         if(left < 0) return -1;
  93         /*
  94         //right = (it->end == NULL) ? 4 : it->begin - s;
  95         */
  96         if(right < 1) return -1;
  97
  98         /*
  99         // get c(0), t(0)
 100         */
 101         c(0) = rstr[0]; /* may be '\0' */
 102     if(!th_isthai(c(0))) return -1;
 103         t(0) = twbtype(c(0));
 104         if(!(t(0) & A)) return -1;
 105
 106         /*
 107         // get c(-1), t(-1)
 108         */
 109         if(left >= 1) {
 110                 c(-1) = lstr[-1];
 111                 if(!th_isthai(c(-1))) return 0;
 112                 t(-1) = twbtype(c(-1));
 113                 if(!(t(-1) & A)) return 0;      /* handle punctuation marks here */
 114         } else { c(-1) = 0; t(-1) = 0; }
 115
 116         /*
 117         // get c(1..2), t(1..2)
 118         */
 119         for(i = 1; i <= 2; i++) {
 120                 if(i >= right) { c(i) = 0; t(i) = 0; }
 121                 else {
 122                         c(i) = rstr[i]; /* may be '\0'; */
 123                         if(!th_isthai(c(i))) right = i--;
 124                         else {
 125                                 t(i) = twbtype(c(i));
 126                                 if(!(t(i) & A)) right = i--;
 127                         }
 128                 }
 129         }
 130         /*
 131         // get c(-2..-3), t(-2..-3)
 132         */
 133         for(i = -2, j = -2; i >= -3 ; j--) {
 134                 if(j < -left) { c(i) = 0; t(i) = 0; i--; }
 135                 else {
 136                         c(i) = lstr[j];
 137                         if(!th_isthai(c(i))) left = 0;
 138                         else {
 139                                 t(i) = (twb_t)(th_isthai(c(i)) ? twbtype(c(i)) : 0);
 140                                 if(!(t(i) & A)) left = 0;
 141                                 else {
 142                                         if((t(i+1) & MT) && ((t(i) & VR) || (t(i+2) & VR))) {
 143                                                 c(i+1) = c(i); t(i+1) = t(i);
 144                                         } else i--;
 145                                 }
 146                         }
 147                 }
 148         }
 149
 150         /*
 151         // prohibit the unlikely
 152         */
 153         if((t(-1) & C) && (t(0) & C)) {
 154           if((t(-1) & CHE) || (t(0) & CHB)) return -1;
 155         }
 156         /*
 157         // special case : vlao, C/ sara_a|aa, !sara_a
 158         */
 159         if((t(-3) & (VLA|VLO)) && (t(-2) & C) && (c(0) != TH_SARA_A) &&
 160                 (c(-1) == TH_SARA_A || c(-0) == TH_SARA_AA)) return 0;
 161
 162         /*
 163         // prohibit break
 164         */
 165         if(t(0) & NB) return -1;
 166         if(t(-1) & NE) return -1;
 167
 168
 169   /*
 170         // apply 100% rules
 171   */
 172         if(t(-1) & VRE) {
 173                 if(c(-2) == TH_SARA_AA && c(-1) == TH_SARA_A) return 0;
 174                 return -1; /* usually too short syllable, part of word */
 175         }
 176
 177         if(t(-2) & VRE) return -1;
 178
 179         if((t(0) & C) && (t(1) & (VR|MT)) && (c(2) != TH_THANTHAKHAT)) { /*?C, NB */
 180                 if((t(-1) & (VRS|VRX))  && c(1) == TH_SARA_I) return -1; /* exception */
 181                 if(t(-1) & (V|M)) return 0; /* !C/ C, NB */
 182                 if(t(-2) & VRS) return 0;       /* VRS, C / C, NB */
 183                 if(!(t(0) & C2) && c(1) == TH_SARA_I) { /*      / !C2 or /c, sara_i */
 184                         if(t(-2) & VRX) return 0; /* VRX, C / C, NB ? 100%? */
 185                         if(t(-2) & VC) return 0;        /* VC, C / C, NB ? 100% */
 186                 }
 187         }
 188         if((t(-1) & VRX) && (t(0) & CC)) return 0;                              /* VRX/ CC */
 189         if((t(-2) & VRS) && (t(-1) & C) && (t(0) & (V|M))) return 0;/* VRS, C/ !C */
 190
 191
 192         if((t(0) & CX) && (t(1) & C2) && (c(2) != TH_THANTHAKHAT)) {
 193                 if((t(-2) & A) && (t(-1) & CX)) return 0; /* A, CX / CX, C2 */
 194                 if((t(-2) & CX) && (t(-1) & MT)) return 0; /* CX, MT / CX, C2 */
 195         }
 196         /*
 197         // apply 90% rules
 198         */
 199         if(t(0) & VL) return 0;
 200         if(t(1) & VL) return -1;
 201         if(c(-1) == TH_THANTHAKHAT && c(-2) != TH_RORUA && c(-2) != TH_LOLING) return 0;
 202
 203         /*
 204         //return -1;
 205         // apply 80% rules
 206         */
 207         if(t(0) & CHE) {
 208                 if((t(-2) & VRS) && (t(-1) & C)) return 0;      /* VRS, C/ CHE */
 209                 /*if(t(-1) & VRX) return 0;                                     // VRX/ CHE */
 210                 if(t(-1) & VC) return 0;                                        /* VC/ CHE */
 211         }
 212         if(t(-1) & CHB) {
 213                 if((t(0) & C) && (t(1) & VR)) return 0; /* CHB/ CC, VR */
 214                 if(t(0) & VC) return 0;                                 /* CHB/ VC */
 215         }
 216
 217         if((t(-2) & VL) && (t(1) & VR)) { /* VL, C? C, VR */
 218                 if(t(-2) & VLI) return 0;  /* VLI,C/C,VR .*/
 219                 else { /* vlao, C ? C , VR */
 220                         if(c(1) == TH_SARA_A) return 2; /* vlao, C, C, sara_a/ */
 221                         if(t(-2) & VLO) return 0; /* VLO, C/ C, !sara_a */
 222                         if(!(t(1) & VRA)) return 0;     /* VLA, C/ C, !vca */
 223                 }
 224         }
 225         /* C,MT,C */
 226         if((t(-2) & C) && (t(-1) & MT) && (t(0) & CX)) return 1;
 227
 228         return -1;
 229 }
 230
 231
 232 int TrbFollowing(const th_char *begin, int length, int offset)
 233 /*
 234 //(ThBreakIterator *this, int offset)
 235 */
 236 {
 237         const th_char *w = begin + offset;
 238     const th_char *end = begin + length;
 239         while(w < end && *w && !th_isthai(*w) && th_isspace(*w)) w++;
 240
 241         if(w < end && *w && !th_isthai(*w)) {
 242                 int english = FALSE;
 243                 while(w < end && *w && !th_isthai(*w) && !th_isspace(*w)) {
 244                         if(th_isalpha(*w)) english = TRUE;
 245                         w++;
 246                 }
 247                 if(english || w == end ||
 248             (!th_isthai(*w) && th_isspace(*w))) return w - begin;
 249         }
 250         if(w == end || *w == 0 || !th_isthai(*w)) return w - begin;
 251         w++;
 252         if(w < end && *w && th_isthai(*w)) {
 253                 int brk = TrbWordBreakPos(begin, w-begin, w, end-w);
 254                 while (brk < 0) {
 255                         w++;
 256                         if(w == end || *w == 0 || !th_isthai(*w)) break;
 257                         brk = TrbWordBreakPos(begin, w-begin, w, end-w);
 258                 }
 259         if (brk > 0) w += brk;
 260         }
 261         if(w < end && *w && !th_isthai(*w)) {
 262                 while(w < end && *w && !th_isthai(*w) &&
 263             !th_isalpha(*w) && !th_isspace(*w)) w++;
 264         }
 265         return w - begin;
 266 }
 267
 268
 269 /*
 270 /////////////////////////////////////////////////
 271 */
 272 const twb_t  _TwbType[0x100-0xa0] = {
 273 #if 0
 274 /* 80 € */      T,
 275 /* 81-8f */     0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
 276 /* 90 � */      T,
 277 /* 91-9f */     0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
 278 #endif
 279 /* a0   */      0,
 280 /* a1 ¡ */      CS,
 281 /* a2 ¢ */      CS | CHE,
 282 /* a3 £ */      CC | CHE,
 283 /* a4 ¤ */      CS | CHE,
 284 /* a5 ¥ */      CC | CHE,
 285 /* a6 ¦ */      CS,
 286 /* a7 § */      CS | CHB,
 287 /* a8 ¨ */      CS,
 288 /* a9 © */      CC | CHE,
 289 /* aa ª */      CS,
 290 /* ab « */      CC | CHE,
 291 /* ac ¬ */      CC | CHB | CHE,
 292 /* ad  */      CS | CHB,
 293 /* ae ® */      CS | CHB,
 294 /* af ¯ */      CS | CHB,
 295 /* b0 ° */      CS,
 296 /* b1 ± */      CS | CHB | CHE,
 297 /* b2 ² */      CS | CHB | CHE,
 298 /* b3 ³ */      CS | CHB,
 299 /* b4 ´ */      CS,
 300 /* b5 µ */      CS,
 301 /* b6 ¶ */      CS,
 302 /* b7 · */      CS,
 303 /* b8 ¸ */      CS,
 304 /* b9 ¹ */      CS,
 305 /* ba º */      CS,
 306 /* bb » */      CS,
 307 /* bc ¼ */      CC | CHE,
 308 /* bd ½ */      CC | CHE,
 309 /* be ¾ */      CS,
 310 /* bf ¿ */      CS,
 311 /* c0 À */      CS | CHE,
 312 /* c1 Á */      CS,
 313 /* c2 Â */      CS,
 314 /* c3 Ã */      CS | C2 | CHE, /* ? add CHE  */
 315 /* c4 Ä */      VC | CHE,
 316 /* c5 Å */      CS | C2,
 317 /* c6 Æ */      VC | CHE,
 318 /* c7 Ç */      VC | C2,
 319 /* c8 È */      CS,
 320 /* c9 É */      CS | CHB,
 321 /* ca Ê */      CS | CHE,
 322 /* cb Ë */      CC | CHE,
 323 /* CC Ì */      CS | CHB | CHE,
 324 /* cd Í */      VC,
 325 /* ce Î */      CC | CHE,
 326 /* cf Ï */      T,
 327 /* d0 Ð */      VRE | VRA,
 328 /* d1  Ñ */     VRS,
 329 /* d2 Ò */      VRX | VRA,
 330 /* d3  Ó */     VRE,
 331 /* d4  Ô */     VRX | VRA,
 332 /* d5  Õ */     VRX | VRA,
 333 /* d6  Ö */     VRS,
 334 /* d7  × */     VRS | VRA,
 335 /* d8  Ø */     VRX,
 336 /* d9  Ù */     VRX,
 337 /* da  Ú */     T,
 338 /* db Û */ 0,
 339 /* dc Ü */ 0,
 340 /* dd Ý */ 0,
 341 /* de Þ */ 0,
 342 /* df ß */      T,
 343 /* e0 à */      VLA,
 344 /* e1 á */      VLO,
 345 /* e2 â */      VLO,
 346 /* e3 ã */      VLI,
 347 /* e4 ä */      VLI,
 348 /* e5 å */      VRE,
 349 /* e6 æ */      M,
 350 /* e7  ç */     M,
 351 /* e8  è */     M | MT,
 352 /* e9  é */     M | MT,
 353 /* ea  ê */     M | MT,
 354 /* eb  ë */     M | MT,
 355 /* ec  ì */     M,
 356 /* ed  í */     T,
 357 /* ee  î */     T,
 358 /* ef ï */      T,
 359 /* f0 ð */      T,
 360 /* f1 ñ */      T,
 361 /* f2 ò */      T,
 362 /* f3 ó */      T,
 363 /* f4 ô */      T,
 364 /* f5 õ */      T,
 365 /* f6 ö */      T,
 366 /* f7 ÷ */      T,
 367 /* f8 ø */      T,
 368 /* f9 ù */      T,
 369 /* fa ú */      T,
 370 /* fb û */      T,
 371 /* fc ü */ 0,
 372 /* fd ý */ 0,
 373 /* fe þ */ 0,
 374 /* ff ’ */ 0
 375 };