sl@0: /*
sl@0:  *
sl@0:  * (C) Copyright IBM Corp. 1998-2004 - All Rights Reserved
sl@0:  *
sl@0:  */
sl@0: 
sl@0: #include "LETypes.h"
sl@0: #include "LEGlyphFilter.h"
sl@0: #include "OpenTypeTables.h"
sl@0: #include "LEGlyphStorage.h"
sl@0: #include "ThaiShaping.h"
sl@0: 
sl@0: U_NAMESPACE_BEGIN
sl@0: 
sl@0: enum {
sl@0:     CH_SPACE        = 0x0020,
sl@0:     CH_YAMAKKAN     = 0x0E4E,
sl@0:     CH_MAI_HANAKAT  = 0x0E31,
sl@0:     CH_SARA_AA      = 0x0E32,
sl@0:     CH_SARA_AM      = 0x0E33,
sl@0:     CH_SARA_UEE     = 0x0E37,
sl@0:     CH_MAITAIKHU    = 0x0E47,
sl@0:     CH_NIKHAHIT     = 0x0E4D,
sl@0:     CH_SARA_U       = 0x0E38,
sl@0:     CH_PHINTHU      = 0x0E3A,
sl@0:     CH_YO_YING      = 0x0E0D,
sl@0:     CH_THO_THAN     = 0x0E10,
sl@0:     CH_DOTTED_CIRCLE = 0x25CC
sl@0: };
sl@0: 
sl@0:     le_uint8 ThaiShaping::getCharClass(LEUnicode ch)
sl@0: {
sl@0:     le_uint8 charClass = NON;
sl@0:     
sl@0:     if (ch >= 0x0E00 && ch <= 0x0E5B) {
sl@0:         charClass = classTable[ch - 0x0E00];
sl@0:     }
sl@0:     
sl@0:     return charClass;
sl@0: }
sl@0: 
sl@0: 
sl@0: LEUnicode ThaiShaping::leftAboveVowel(LEUnicode vowel, le_uint8 glyphSet)
sl@0: {
sl@0:     static const LEUnicode leftAboveVowels[][7] = {
sl@0:         {0x0E61, 0x0E32, 0x0E33, 0x0E64, 0x0E65, 0x0E66, 0x0E67},
sl@0:         {0xF710, 0x0E32, 0x0E33, 0xF701, 0xF702, 0xF703, 0xF704},
sl@0:         {0xF884, 0x0E32, 0x0E33, 0xF885, 0xF886, 0xF887, 0xF788},
sl@0:         {0x0E31, 0x0E32, 0x0E33, 0x0E34, 0x0E35, 0x0E36, 0x0E37}
sl@0:     };
sl@0:    
sl@0:     if (vowel >= CH_MAI_HANAKAT && vowel <= CH_SARA_UEE) {
sl@0:         return leftAboveVowels[glyphSet][vowel - CH_MAI_HANAKAT];
sl@0:     }
sl@0:     
sl@0:     if (vowel == CH_YAMAKKAN && glyphSet == 0) {
sl@0:         return 0x0E7E;
sl@0:     }
sl@0:     
sl@0:     return vowel;
sl@0: }
sl@0: 
sl@0: LEUnicode ThaiShaping::lowerRightTone(LEUnicode tone, le_uint8 glyphSet)
sl@0: {
sl@0:     static const LEUnicode lowerRightTones[][7] = {
sl@0:         {0x0E68, 0x0E69, 0x0E6A, 0x0E6B, 0x0E6C, 0x0E6D, 0x0E6E},
sl@0:         {0x0E47, 0xF70A, 0xF70B, 0xF70C, 0xF70D, 0xF70E, 0x0E4D},
sl@0:         {0x0E47, 0xF88B, 0xF88E, 0xF891, 0xF894, 0xF897, 0x0E4D},
sl@0:         {0x0E47, 0x0E48, 0x0E49, 0x0E4A, 0x0E4B, 0x0E4C, 0x0E4D}
sl@0:     };
sl@0: 
sl@0:     if (tone >= CH_MAITAIKHU && tone <= CH_NIKHAHIT) {
sl@0:         return lowerRightTones[glyphSet][tone - CH_MAITAIKHU];
sl@0:     }
sl@0:     
sl@0:     return tone;
sl@0: }
sl@0: 
sl@0: LEUnicode ThaiShaping::lowerLeftTone(LEUnicode tone, le_uint8 glyphSet)
sl@0: {
sl@0:     static const LEUnicode lowerLeftTones[][7] = {
sl@0:         {0x0E76, 0x0E77, 0x0E78, 0x0E79, 0x0E7A, 0x0E7B, 0x0E7C},
sl@0:         {0xF712, 0xF705, 0xF706, 0xF707, 0xF708, 0xF709, 0xF711},
sl@0:         {0xF889, 0xF88C, 0xF88F, 0xF892, 0xF895, 0xF898, 0xF899},
sl@0:         {0x0E47, 0x0E48, 0x0E49, 0x0E4A, 0x0E4B, 0x0E4C, 0x0E4D}
sl@0:     };
sl@0: 
sl@0:     if (tone >= CH_MAITAIKHU && tone <= CH_NIKHAHIT) {
sl@0:         return lowerLeftTones[glyphSet][tone - CH_MAITAIKHU];
sl@0:     }
sl@0:     
sl@0:     return tone;
sl@0: }
sl@0: 
sl@0: LEUnicode ThaiShaping::upperLeftTone(LEUnicode tone, le_uint8 glyphSet)
sl@0: {
sl@0:     static const LEUnicode upperLeftTones[][7] = {
sl@0:         {0x0E6F, 0x0E70, 0x0E71, 0x0E72, 0x0E73, 0x0E74, 0x0E75},
sl@0:         {0xF712, 0xF713, 0xF714, 0xF715, 0xF716, 0xF717, 0xF711},
sl@0:         {0xF889, 0xF88A, 0xF88D, 0xF890, 0xF893, 0xF896, 0xF899},
sl@0:         {0x0E47, 0x0E48, 0x0E49, 0x0E4A, 0x0E4B, 0x0E4C, 0x0E4D}
sl@0:     };
sl@0: 
sl@0:     if (tone >= CH_MAITAIKHU && tone <= CH_NIKHAHIT) {
sl@0:         return upperLeftTones[glyphSet][tone - CH_MAITAIKHU];
sl@0:     }
sl@0:     
sl@0:     return tone;
sl@0: }
sl@0: 
sl@0: LEUnicode ThaiShaping::lowerBelowVowel(LEUnicode vowel, le_uint8 glyphSet)
sl@0: {
sl@0:     static const LEUnicode lowerBelowVowels[][3] = {
sl@0:         {0x0E3C, 0x0E3D, 0x0E3E},
sl@0:         {0xF718, 0xF719, 0xF71A},
sl@0:         {0x0E38, 0x0E39, 0x0E3A},
sl@0:         {0x0E38, 0x0E39, 0x0E3A}
sl@0: 
sl@0:     };
sl@0: 
sl@0:     if (vowel >= CH_SARA_U && vowel <= CH_PHINTHU) {
sl@0:         return lowerBelowVowels[glyphSet][vowel - CH_SARA_U];
sl@0:     }
sl@0:     
sl@0:     return vowel;
sl@0: }
sl@0: 
sl@0: LEUnicode ThaiShaping::noDescenderCOD(LEUnicode cod, le_uint8 glyphSet)
sl@0: {
sl@0:     static const LEUnicode noDescenderCODs[][4] = {
sl@0:         {0x0E60, 0x0E0E, 0x0E0F, 0x0E63},
sl@0:         {0xF70F, 0x0E0E, 0x0E0F, 0xF700},
sl@0:         {0x0E0D, 0x0E0E, 0x0E0F, 0x0E10},
sl@0:         {0x0E0D, 0x0E0E, 0x0E0F, 0x0E10}
sl@0: 
sl@0:     };
sl@0: 
sl@0:     if (cod >= CH_YO_YING && cod <= CH_THO_THAN) {
sl@0:         return noDescenderCODs[glyphSet][cod - CH_YO_YING];
sl@0:     }
sl@0:     
sl@0:     return cod;
sl@0: }
sl@0: 
sl@0: le_uint8 ThaiShaping::doTransition (StateTransition transition, LEUnicode currChar, le_int32 inputIndex, le_uint8 glyphSet,
sl@0:         LEUnicode errorChar, LEUnicode *outputBuffer, LEGlyphStorage &glyphStorage, le_int32 &outputIndex)
sl@0: {
sl@0:     LEErrorCode success = LE_NO_ERROR;
sl@0: 
sl@0:     switch (transition.action) {
sl@0:     case tA:
sl@0:         glyphStorage.setCharIndex(outputIndex, inputIndex, success);
sl@0:         outputBuffer[outputIndex++] = currChar;
sl@0:         break;
sl@0:         
sl@0:     case tC:
sl@0:         glyphStorage.setCharIndex(outputIndex, inputIndex, success);
sl@0:         outputBuffer[outputIndex++] = currChar;
sl@0:         break;
sl@0:         
sl@0:     case tD:
sl@0:         glyphStorage.setCharIndex(outputIndex, inputIndex, success);
sl@0:         outputBuffer[outputIndex++] = leftAboveVowel(currChar, glyphSet);
sl@0:         break;
sl@0:         
sl@0:     case tE:
sl@0:         glyphStorage.setCharIndex(outputIndex, inputIndex, success);
sl@0:         outputBuffer[outputIndex++] = lowerRightTone(currChar, glyphSet);
sl@0:         break;
sl@0:         
sl@0:     case tF:
sl@0:         glyphStorage.setCharIndex(outputIndex, inputIndex, success);
sl@0:         outputBuffer[outputIndex++] = lowerLeftTone(currChar, glyphSet);
sl@0:         break;
sl@0:     
sl@0:     case tG:
sl@0:         glyphStorage.setCharIndex(outputIndex, inputIndex, success);
sl@0:         outputBuffer[outputIndex++] = upperLeftTone(currChar, glyphSet);
sl@0:         break;
sl@0:         
sl@0:     case tH:
sl@0:     {
sl@0:         LEUnicode cod = outputBuffer[outputIndex - 1];
sl@0:         LEUnicode coa = noDescenderCOD(cod, glyphSet);
sl@0: 
sl@0:         if (cod != coa) {
sl@0:             outputBuffer[outputIndex - 1] = coa;
sl@0:             
sl@0:             glyphStorage.setCharIndex(outputIndex, inputIndex, success);
sl@0:             outputBuffer[outputIndex++] = currChar;
sl@0:             break;
sl@0:         }
sl@0: 
sl@0:         glyphStorage.setCharIndex(outputIndex, inputIndex, success);
sl@0:         outputBuffer[outputIndex++] = lowerBelowVowel(currChar, glyphSet);
sl@0:         break;
sl@0:     }
sl@0:         
sl@0:     case tR:
sl@0:         glyphStorage.setCharIndex(outputIndex, inputIndex, success);
sl@0:         outputBuffer[outputIndex++] = errorChar;
sl@0: 
sl@0:         glyphStorage.setCharIndex(outputIndex, inputIndex, success);
sl@0:         outputBuffer[outputIndex++] = currChar;
sl@0:         break;
sl@0:         
sl@0:     case tS:
sl@0:         if (currChar == CH_SARA_AM) {
sl@0:             glyphStorage.setCharIndex(outputIndex, inputIndex, success);
sl@0:             outputBuffer[outputIndex++] = errorChar;
sl@0:         }
sl@0: 
sl@0:         glyphStorage.setCharIndex(outputIndex, inputIndex, success);
sl@0:         outputBuffer[outputIndex++] = currChar;
sl@0:         break;
sl@0:         
sl@0:     default:
sl@0:         // FIXME: if we get here, there's an error
sl@0:         // in the state table!
sl@0:         glyphStorage.setCharIndex(outputIndex, inputIndex, success);
sl@0:         outputBuffer[outputIndex++] = currChar;
sl@0:         break;
sl@0:      }
sl@0:      
sl@0:      return transition.nextState;
sl@0: }
sl@0: 
sl@0: le_uint8 ThaiShaping::getNextState(LEUnicode ch, le_uint8 prevState, le_int32 inputIndex, le_uint8 glyphSet, LEUnicode errorChar,
sl@0:                               le_uint8 &charClass, LEUnicode *output, LEGlyphStorage &glyphStorage, le_int32 &outputIndex)
sl@0: {
sl@0:     StateTransition transition;
sl@0: 
sl@0:     charClass = getCharClass(ch);
sl@0:     transition = getTransition(prevState, charClass);
sl@0:     
sl@0:     return doTransition(transition, ch, inputIndex, glyphSet, errorChar, output, glyphStorage, outputIndex);
sl@0: }
sl@0: 
sl@0: le_bool ThaiShaping::isLegalHere(LEUnicode ch, le_uint8 prevState)
sl@0: {
sl@0:     le_uint8 charClass = getCharClass(ch);
sl@0:     StateTransition transition = getTransition(prevState, charClass);
sl@0: 
sl@0:     switch (transition.action) {
sl@0:     case tA:
sl@0:     case tC:
sl@0:     case tD:
sl@0:     case tE:
sl@0:     case tF:
sl@0:     case tG:
sl@0:     case tH:
sl@0:         return TRUE;
sl@0:             
sl@0:     case tR:
sl@0:     case tS:
sl@0:         return FALSE;
sl@0:             
sl@0:     default:
sl@0:         // FIXME: if we get here, there's an error
sl@0:         // in the state table!
sl@0:         return FALSE;
sl@0:     }
sl@0: }
sl@0:     
sl@0: le_int32 ThaiShaping::compose(const LEUnicode *input, le_int32 offset, le_int32 charCount, le_uint8 glyphSet,
sl@0:                           LEUnicode errorChar, LEUnicode *output, LEGlyphStorage &glyphStorage)
sl@0: {
sl@0:     le_uint8 state = 0;
sl@0:     le_int32 inputIndex;
sl@0:     le_int32 outputIndex = 0;
sl@0:     le_uint8 conState = 0xFF;
sl@0:     le_int32 conInput = -1;
sl@0:     le_int32 conOutput = -1;
sl@0:     
sl@0:     for (inputIndex = 0; inputIndex < charCount; inputIndex += 1) {
sl@0:         LEUnicode ch = input[inputIndex + offset];
sl@0:         le_uint8 charClass;
sl@0:         
sl@0:         // Decompose SARA AM into NIKHAHIT + SARA AA
sl@0:         if (ch == CH_SARA_AM && isLegalHere(ch, state)) {
sl@0:             outputIndex = conOutput;
sl@0:             state = getNextState(CH_NIKHAHIT, conState, inputIndex, glyphSet, errorChar, charClass,
sl@0:                 output, glyphStorage, outputIndex);
sl@0:             
sl@0:             for (int j = conInput + 1; j < inputIndex; j += 1) {
sl@0:                 ch = input[j + offset];
sl@0:                 state = getNextState(ch, state, j, glyphSet, errorChar, charClass,
sl@0:                     output, glyphStorage, outputIndex);
sl@0:             }
sl@0:             
sl@0:             ch = CH_SARA_AA;
sl@0:         }
sl@0:         
sl@0:         state = getNextState(ch, state, inputIndex, glyphSet, errorChar, charClass,
sl@0:             output, glyphStorage, outputIndex);
sl@0:         
sl@0:         if (charClass >= CON && charClass <= COD) {
sl@0:             conState = state;
sl@0:             conInput = inputIndex;
sl@0:             conOutput = outputIndex;
sl@0:         }
sl@0:     }
sl@0:     
sl@0:     return outputIndex;
sl@0: }
sl@0: 
sl@0: U_NAMESPACE_END