/*

 * %W% %E%

 *

 * (C) Copyright IBM Corp. 1998-2003 - All Rights Reserved

 *

 */

#include "LETypes.h"

#include "LEGlyphFilter.h"

#include "OpenTypeTables.h"

#include "GlyphSubstitutionTables.h"

#include "LigatureSubstSubtables.h"

#include "GlyphIterator.h"

#include "LESwaps.h"

U_NAMESPACE_BEGIN

le_uint32 LigatureSubstitutionSubtable::process(GlyphIterator *glyphIterator, const LEGlyphFilter *filter) const

{

    LEGlyphID glyph = glyphIterator->getCurrGlyphID();

    le_int32 coverageIndex = getGlyphCoverage(glyph);

    if (coverageIndex >= 0) {

        Offset ligSetTableOffset = SWAPW(ligSetTableOffsetArray[coverageIndex]);

        const LigatureSetTable *ligSetTable = (const LigatureSetTable *) ((char *) this + ligSetTableOffset);

        le_uint16 ligCount = SWAPW(ligSetTable->ligatureCount);

        for (le_uint16 lig = 0; lig < ligCount; lig += 1) {

            Offset ligTableOffset = SWAPW(ligSetTable->ligatureTableOffsetArray[lig]);

            const LigatureTable *ligTable = (const LigatureTable *) ((char *)ligSetTable + ligTableOffset);

            le_uint16 compCount = SWAPW(ligTable->compCount) - 1;

            le_int32 startPosition = glyphIterator->getCurrStreamPosition();

            TTGlyphID ligGlyph = SWAPW(ligTable->ligGlyph);

            le_uint16 comp;

            if (filter != NULL && ! filter->accept(LE_SET_GLYPH(glyph, ligGlyph))) {

                continue;

            }

            for (comp = 0; comp < compCount; comp += 1) {

                if (! glyphIterator->next()) {

                    break;

                }

                if (LE_GET_GLYPH(glyphIterator->getCurrGlyphID()) != SWAPW(ligTable->componentArray[comp])) {

                    break;

                }

            }

            if (comp == compCount) {

                GlyphIterator tempIterator(*glyphIterator);

                TTGlyphID deletedGlyph = tempIterator.ignoresMarks()? 0xFFFE : 0xFFFF;

                while (comp > 0) {

                    tempIterator.setCurrGlyphID(deletedGlyph);

                    tempIterator.prev();

                    comp -= 1;

                }

                tempIterator.setCurrGlyphID(ligGlyph);

                return compCount + 1;

            }

            glyphIterator->setCurrStreamPosition(startPosition);

        }

    }

    return 0;

}

U_NAMESPACE_END