1/*
2 * (C) Copyright IBM Corp. 1998-2015 - All Rights Reserved
3 *
4 */
5
6#include "LETypes.h"
7#include "LEGlyphFilter.h"
8#include "OpenTypeTables.h"
9#include "GlyphSubstitutionTables.h"
10#include "LigatureSubstSubtables.h"
11#include "GlyphIterator.h"
12#include "LESwaps.h"
13
14U_NAMESPACE_BEGIN
15
16le_uint32 LigatureSubstitutionSubtable::process(const LETableReference &base, GlyphIterator *glyphIterator, LEErrorCode &success, const LEGlyphFilter *filter) const
17{
18    LEGlyphID glyph = glyphIterator->getCurrGlyphID();
19    le_int32 coverageIndex = getGlyphCoverage(base, glyph, success);
20
21    if (coverageIndex >= 0) {
22        Offset ligSetTableOffset = SWAPW(ligSetTableOffsetArray[coverageIndex]);
23        const LigatureSetTable *ligSetTable = (const LigatureSetTable *) ((char *) this + ligSetTableOffset);
24        le_uint16 ligCount = SWAPW(ligSetTable->ligatureCount);
25
26        for (le_uint16 lig = 0; lig < ligCount; lig += 1) {
27            Offset ligTableOffset = SWAPW(ligSetTable->ligatureTableOffsetArray[lig]);
28            const LigatureTable *ligTable = (const LigatureTable *) ((char *)ligSetTable + ligTableOffset);
29            le_uint16 compCount = SWAPW(ligTable->compCount) - 1;
30            LEReferenceToArrayOf<TTGlyphID>
31                componentArrayRef(base, success, ligTable->componentArray, compCount);
32            if (LE_FAILURE(success)) { return 0; }
33            le_int32 startPosition = glyphIterator->getCurrStreamPosition();
34            TTGlyphID ligGlyph = SWAPW(ligTable->ligGlyph);
35            le_uint16 comp;
36
37            for (comp = 0; comp < compCount; comp += 1) {
38                if (! glyphIterator->next()) {
39                    break;
40                }
41
42                if (LE_GET_GLYPH(glyphIterator->getCurrGlyphID()) != SWAPW(ligTable->componentArray[comp])) {
43                    break;
44                }
45            }
46
47            if (comp == compCount && (filter == NULL || filter->accept(LE_SET_GLYPH(glyph, ligGlyph)))) {
48                GlyphIterator tempIterator(*glyphIterator);
49                TTGlyphID deletedGlyph = tempIterator.ignoresMarks()? 0xFFFE : 0xFFFF;
50
51                while (comp > 0) {
52                    tempIterator.setCurrGlyphID(deletedGlyph);
53                    tempIterator.prev();
54
55                    comp -= 1;
56                }
57
58                tempIterator.setCurrGlyphID(ligGlyph);
59
60                return compCount + 1;
61            }
62
63            glyphIterator->setCurrStreamPosition(startPosition);
64        }
65
66    }
67
68    return 0;
69}
70
71U_NAMESPACE_END
72