/*

  * (C) Copyright IBM Corp. 1998-2004 - All Rights Reserved

  *

  */

 #include "LETypes.h"

 #include "LEFontInstance.h"

 #include "OpenTypeTables.h"

 #include "AnchorTables.h"

 #include "MarkArrays.h"

 #include "GlyphPositioningTables.h"

 #include "AttachmentPosnSubtables.h"

 #include "MarkToLigaturePosnSubtables.h"

 #include "GlyphIterator.h"

 #include "LESwaps.h"

 U_NAMESPACE_BEGIN

 LEGlyphID MarkToLigaturePositioningSubtable::findLigatureGlyph(GlyphIterator *glyphIterator) const

 {

     if (glyphIterator->prev()) {

         return glyphIterator->getCurrGlyphID();

     }

     return 0xFFFF;

 }

 le_int32 MarkToLigaturePositioningSubtable::process(GlyphIterator *glyphIterator, const LEFontInstance *fontInstance) const

 {

     LEGlyphID markGlyph = glyphIterator->getCurrGlyphID();

     le_int32 markCoverage = getGlyphCoverage((LEGlyphID) markGlyph);

     if (markCoverage < 0) {

         // markGlyph isn't a covered mark glyph

         return 0;

     }

     LEPoint markAnchor;

     const MarkArray *markArray = (const MarkArray *) ((char *) this + SWAPW(markArrayOffset));

     le_int32 markClass = markArray->getMarkClass(markGlyph, markCoverage, fontInstance, markAnchor);

     le_uint16 mcCount = SWAPW(classCount);

     if (markClass < 0 || markClass >= mcCount) {

         // markGlyph isn't in the mark array or its

         // mark class is too big. The table is mal-formed!

         return 0;

     }

     // FIXME: we probably don't want to find a ligature before a previous base glyph...

     GlyphIterator ligatureIterator(*glyphIterator, (le_uint16) (lfIgnoreMarks /*| lfIgnoreBaseGlyphs*/));

     LEGlyphID ligatureGlyph = findLigatureGlyph(&ligatureIterator);

     le_int32 ligatureCoverage = getBaseCoverage((LEGlyphID) ligatureGlyph);

     const LigatureArray *ligatureArray = (const LigatureArray *) ((char *) this + SWAPW(baseArrayOffset));

     le_uint16 ligatureCount = SWAPW(ligatureArray->ligatureCount);

     if (ligatureCoverage < 0 || ligatureCoverage >= ligatureCount) {

         // The ligature glyph isn't covered, or the coverage

         // index is too big. The latter means that the

         // table is mal-formed...

         return 0;

     }

     le_int32 markPosition = glyphIterator->getCurrStreamPosition();

     Offset ligatureAttachOffset = SWAPW(ligatureArray->ligatureAttachTableOffsetArray[ligatureCoverage]);

     const LigatureAttachTable *ligatureAttachTable = (const LigatureAttachTable *) ((char *) ligatureArray + ligatureAttachOffset);

     le_int32 componentCount = SWAPW(ligatureAttachTable->componentCount);

     le_int32 component = ligatureIterator.getMarkComponent(markPosition);

     if (component >= componentCount) {

         // should really just bail at this point...

         component = componentCount - 1;

     }

     const ComponentRecord *componentRecord = &ligatureAttachTable->componentRecordArray[component * mcCount];

     Offset anchorTableOffset = SWAPW(componentRecord->ligatureAnchorTableOffsetArray[markClass]);

     const AnchorTable *anchorTable = (const AnchorTable *) ((char *) ligatureAttachTable + anchorTableOffset);

     LEPoint ligatureAnchor, markAdvance, pixels;

     anchorTable->getAnchor(ligatureGlyph, fontInstance, ligatureAnchor);

     fontInstance->getGlyphAdvance(markGlyph, pixels);

     fontInstance->pixelsToUnits(pixels, markAdvance);

     float anchorDiffX = ligatureAnchor.fX - markAnchor.fX;

     float anchorDiffY = ligatureAnchor.fY - markAnchor.fY;

     glyphIterator->setCurrGlyphBaseOffset(ligatureIterator.getCurrStreamPosition());

     if (glyphIterator->isRightToLeft()) {

         glyphIterator->setCurrGlyphPositionAdjustment(anchorDiffX, anchorDiffY, -markAdvance.fX, -markAdvance.fY);

     } else {

         LEPoint ligatureAdvance;

         fontInstance->getGlyphAdvance(ligatureGlyph, pixels);

         fontInstance->pixelsToUnits(pixels, ligatureAdvance);

         glyphIterator->setCurrGlyphPositionAdjustment(anchorDiffX - ligatureAdvance.fX, anchorDiffY - ligatureAdvance.fY, -markAdvance.fX, -markAdvance.fY);

     }

     return 1;

 }

 U_NAMESPACE_END