/***************************************************************************

 *

 *   Copyright (C) 1998-2002, International Business Machines

 *   Corporation and others.  All Rights Reserved.

 *

 ************************************************************************/

 #include <stdio.h>

 #include "LETypes.h"

 #include "FontObject.h"

 #include "LESwaps.h"

 FontObject::FontObject(char *fileName)

   : directory(NULL), numTables(0), searchRange(0),entrySelector(0),

     cmapTable(NULL), cmSegCount(0), cmSearchRange(0), cmEntrySelector(0),

     cmEndCodes(NULL), cmStartCodes(NULL), cmIdDelta(0), cmIdRangeOffset(0),

     headTable(NULL), hmtxTable(NULL), numGlyphs(0), numOfLongHorMetrics(0), file(NULL)

 {

     file = fopen(fileName, "rb");

     if (file == NULL) {

         printf("?? Couldn't open %s", fileName);

         return;

     }

     SFNTDirectory tempDir;

     fread(&tempDir, sizeof tempDir, 1, file);

     numTables       = SWAPW(tempDir.numTables);

     searchRange     = SWAPW(tempDir.searchRange) >> 4;

     entrySelector   = SWAPW(tempDir.entrySelector);

     rangeShift      = SWAPW(tempDir.rangeShift) >> 4;

     int dirSize = sizeof tempDir + ((numTables - ANY_NUMBER) * sizeof(DirectoryEntry));

     directory = (SFNTDirectory *) new char[dirSize];

     fseek(file, 0L, SEEK_SET);

     fread(directory, sizeof(char), dirSize, file);

     initUnicodeCMAP();

 }

 FontObject::~FontObject()

 {

     fclose(file);

     delete[] directory;

     delete[] cmapTable;

     delete[] headTable;

     delete[] hmtxTable;

 }

 void FontObject::deleteTable(void *table)

 {

     delete[] (char *) table;

 }

 DirectoryEntry *FontObject::findTable(LETag tag)

 {

     le_uint16 table = 0;

     le_uint16 probe = 1 << entrySelector;

     if (SWAPL(directory->tableDirectory[rangeShift].tag) <= tag) {

         table = rangeShift;

     }

     while (probe > (1 << 0)) {

         probe >>= 1;

         if (SWAPL(directory->tableDirectory[table + probe].tag) <= tag) {

             table += probe;

         }

     }

     if (SWAPL(directory->tableDirectory[table].tag) == tag) {

         return &directory->tableDirectory[table];

     }

     return NULL;

 }

 void *FontObject::readTable(LETag tag, le_uint32 *length)

 {

     DirectoryEntry *entry = findTable(tag);

     if (entry == NULL) {

         *length = 0;

         return NULL;

     }

     *length = SWAPL(entry->length);

     void *table = new char[*length];

     fseek(file, SWAPL(entry->offset), SEEK_SET);

     fread(table, sizeof(char), *length, file);

     return table;

 }

 CMAPEncodingSubtable *FontObject::findCMAP(le_uint16 platformID, le_uint16 platformSpecificID)

 {

     LETag cmapTag = 0x636D6170; // 'cmap'

     if (cmapTable == NULL) {

         le_uint32 length;

         cmapTable = (CMAPTable *) readTable(cmapTag, &length);

     }

     if (cmapTable != NULL) {

         le_uint16 i;

         le_uint16 nSubtables = SWAPW(cmapTable->numberSubtables);

         for (i = 0; i < nSubtables; i += 1) {

             CMAPEncodingSubtableHeader *esh = &cmapTable->encodingSubtableHeaders[i];

             if (SWAPW(esh->platformID) == platformID &&

                 SWAPW(esh->platformSpecificID) == platformSpecificID) {

                 return (CMAPEncodingSubtable *) ((char *) cmapTable + SWAPL(esh->encodingOffset));

             }

         }

     }

     return NULL;

 }

 void FontObject::initUnicodeCMAP()

 {

     CMAPEncodingSubtable *encodingSubtable = findCMAP(3, 1);

     if (encodingSubtable == 0 ||

         SWAPW(encodingSubtable->format) != 4) {

         printf("Can't find unicode 'cmap'");

         return;

     }

     CMAPFormat4Encoding *header = (CMAPFormat4Encoding *) encodingSubtable;

     cmSegCount = SWAPW(header->segCountX2) / 2;

     cmSearchRange = SWAPW(header->searchRange);

     cmEntrySelector = SWAPW(header->entrySelector);

     cmRangeShift = SWAPW(header->rangeShift) / 2;

     cmEndCodes = &header->endCodes[0];

     cmStartCodes = &header->endCodes[cmSegCount + 1]; // + 1 for reservedPad...

     cmIdDelta = &cmStartCodes[cmSegCount];

     cmIdRangeOffset = &cmIdDelta[cmSegCount];

 }

 LEGlyphID FontObject::unicodeToGlyph(LEUnicode32 unicode32)

 {

     if (unicode32 >= 0x10000) {

         return 0;

     }

     LEUnicode16 unicode = (LEUnicode16) unicode32;

     le_uint16 index = 0;

     le_uint16 probe = 1 << cmEntrySelector;

     LEGlyphID result = 0;

     if (SWAPW(cmStartCodes[cmRangeShift]) <= unicode) {

         index = cmRangeShift;

     }

     while (probe > (1 << 0)) {

         probe >>= 1;

         if (SWAPW(cmStartCodes[index + probe]) <= unicode) {

             index += probe;

         }

     }

     if (unicode >= SWAPW(cmStartCodes[index]) && unicode <= SWAPW(cmEndCodes[index])) {

         if (cmIdRangeOffset[index] == 0) {

             result = (LEGlyphID) unicode;

         } else {

             le_uint16 offset = unicode - SWAPW(cmStartCodes[index]);

             le_uint16 rangeOffset = SWAPW(cmIdRangeOffset[index]);

             le_uint16 *glyphIndexTable = (le_uint16 *) ((char *) &cmIdRangeOffset[index] + rangeOffset);

             result = SWAPW(glyphIndexTable[offset]);

         }

         result += SWAPW(cmIdDelta[index]);

     } else {

         result = 0;

     }

     return result;

 }

 le_uint16 FontObject::getUnitsPerEM()

 {

     if (headTable == NULL) {

         LETag headTag = 0x68656164; // 'head'

         le_uint32 length;

         headTable = (HEADTable *) readTable(headTag, &length);

     }

     return SWAPW(headTable->unitsPerEm);

 }

 le_uint16 FontObject::getGlyphAdvance(LEGlyphID glyph)

 {

     if (hmtxTable == NULL) {

         LETag maxpTag = 0x6D617870; // 'maxp'

         LETag hheaTag = 0x68686561; // 'hhea'

         LETag hmtxTag = 0x686D7478; // 'hmtx'

         le_uint32 length;

         HHEATable *hheaTable;

         MAXPTable *maxpTable = (MAXPTable *) readTable(maxpTag, &length);

         numGlyphs = SWAPW(maxpTable->numGlyphs);

         deleteTable(maxpTable);

         hheaTable = (HHEATable *) readTable(hheaTag, &length);

         numOfLongHorMetrics = SWAPW(hheaTable->numOfLongHorMetrics);

         deleteTable(hheaTable);

         hmtxTable = (HMTXTable *) readTable(hmtxTag, &length);

     }

     le_uint16 index = glyph;

     if (glyph >= numGlyphs) {

         return 0;

     }

     if (glyph >= numOfLongHorMetrics) {

         index = numOfLongHorMetrics - 1;

     }

     return SWAPW(hmtxTable->hMetrics[index].advanceWidth);

 }