/*

 *

 * (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 "MarkToBasePosnSubtables.h"

#include "GlyphIterator.h"

#include "LESwaps.h"

U_NAMESPACE_BEGIN

LEGlyphID MarkToBasePositioningSubtable::findBaseGlyph(GlyphIterator *glyphIterator) const

{

    if (glyphIterator->prev()) {

        return glyphIterator->getCurrGlyphID();

    }

    return 0xFFFF;

}

le_int32 MarkToBasePositioningSubtable::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 base glyph before a previous ligature... 

    GlyphIterator baseIterator(*glyphIterator, (le_uint16) (lfIgnoreMarks /*| lfIgnoreLigatures*/));

    LEGlyphID baseGlyph = findBaseGlyph(&baseIterator);

    le_int32 baseCoverage = getBaseCoverage((LEGlyphID) baseGlyph);

    const BaseArray *baseArray = (const BaseArray *) ((char *) this + SWAPW(baseArrayOffset));

    le_uint16 baseCount = SWAPW(baseArray->baseRecordCount);

    if (baseCoverage < 0 || baseCoverage >= baseCount) {

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

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

        // table is mal-formed...

        return 0;

    }

    const BaseRecord *baseRecord = &baseArray->baseRecordArray[baseCoverage * mcCount];

    Offset anchorTableOffset = SWAPW(baseRecord->baseAnchorTableOffsetArray[markClass]);

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

    LEPoint baseAnchor, markAdvance, pixels;

    if (anchorTableOffset == 0) {

        // this means the table is mal-formed...

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

        return 0;

    }

    anchorTable->getAnchor(baseGlyph, fontInstance, baseAnchor);

    fontInstance->getGlyphAdvance(markGlyph, pixels);

    fontInstance->pixelsToUnits(pixels, markAdvance);

    float anchorDiffX = baseAnchor.fX - markAnchor.fX;

    float anchorDiffY = baseAnchor.fY - markAnchor.fY;

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

    if (glyphIterator->isRightToLeft()) {

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

    } else {

        LEPoint baseAdvance;

        fontInstance->getGlyphAdvance(baseGlyph, pixels);

        fontInstance->pixelsToUnits(pixels, baseAdvance);

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

    }

    return 1;

}

U_NAMESPACE_END