xref: /external/icu4c/layout/StateTableProcessor2.cpp

/*
 *
 * (C) Copyright IBM Corp.  and others 1998-2013 - All Rights Reserved
 *
 */

#include "LETypes.h"
#include "MorphTables.h"
#include "StateTables.h"
#include "MorphStateTables.h"
#include "SubtableProcessor2.h"
#include "StateTableProcessor2.h"
#include "LEGlyphStorage.h"
#include "LESwaps.h"
#include "LookupTables.h"
#include <stdio.h>

U_NAMESPACE_BEGIN

StateTableProcessor2::StateTableProcessor2()
{
}

StateTableProcessor2::StateTableProcessor2(const MorphSubtableHeader2 *morphSubtableHeader)
  : SubtableProcessor2(morphSubtableHeader)
{
    stateTableHeader = (const MorphStateTableHeader2 *) morphSubtableHeader;
    nClasses = SWAPL(stateTableHeader->stHeader.nClasses);
    classTableOffset = SWAPL(stateTableHeader->stHeader.classTableOffset);
    stateArrayOffset = SWAPL(stateTableHeader->stHeader.stateArrayOffset);
    entryTableOffset = SWAPL(stateTableHeader->stHeader.entryTableOffset);

    classTable = (LookupTable *) ((char *) &stateTableHeader->stHeader + classTableOffset);
    format = SWAPW(classTable->format);

    stateArray = (const EntryTableIndex2 *) ((char *) &stateTableHeader->stHeader + stateArrayOffset);
}

StateTableProcessor2::~StateTableProcessor2()
{
}

void StateTableProcessor2::process(LEGlyphStorage &glyphStorage)
{
    // Start at state 0
    // XXX: How do we know when to start at state 1?
    le_uint16 currentState = 0;
    le_int32 glyphCount = glyphStorage.getGlyphCount();

    le_int32 currGlyph = 0;
    if ((coverage & scfReverse2) != 0) {  // process glyphs in descending order
        currGlyph = glyphCount - 1;
        dir = -1;
    } else {
        dir = 1;
    }

    beginStateTable();
    switch (format) {
        case ltfSimpleArray: {
#ifdef TEST_FORMAT
            SimpleArrayLookupTable *lookupTable0 = (SimpleArrayLookupTable *) classTable;
            while ((dir == 1 && currGlyph <= glyphCount) || (dir == -1 && currGlyph >= -1)) {
                LookupValue classCode = classCodeOOB;
                if (currGlyph == glyphCount || currGlyph == -1) {
                    // XXX: How do we handle EOT vs. EOL?
                    classCode = classCodeEOT;
                } else {
                    LEGlyphID gid = glyphStorage[currGlyph];
                    TTGlyphID glyphCode = (TTGlyphID) LE_GET_GLYPH(gid);

                    if (glyphCode == 0xFFFF) {
                        classCode = classCodeDEL;
                    } else {
                        classCode = SWAPW(lookupTable0->valueArray[gid]);
                    }
                }
                EntryTableIndex2 entryTableIndex = SWAPW(stateArray[classCode + currentState * nClasses]);
                currentState = processStateEntry(glyphStorage, currGlyph, entryTableIndex); // return a zero-based index instead of a byte offset
            }
#endif
            break;
        }
        case ltfSegmentSingle: {
            SegmentSingleLookupTable *lookupTable2 = (SegmentSingleLookupTable *) classTable;
            while ((dir == 1 && currGlyph <= glyphCount) || (dir == -1 && currGlyph >= -1)) {
                LookupValue classCode = classCodeOOB;
                if (currGlyph == glyphCount || currGlyph == -1) {
                    // XXX: How do we handle EOT vs. EOL?
                    classCode = classCodeEOT;
                } else {
                    LEGlyphID gid = glyphStorage[currGlyph];
                    TTGlyphID glyphCode = (TTGlyphID) LE_GET_GLYPH(gid);

                    if (glyphCode == 0xFFFF) {
                        classCode = classCodeDEL;
                    } else {
                        const LookupSegment *segment = lookupTable2->lookupSegment(lookupTable2->segments, gid);
                        if (segment != NULL) {
                            classCode = SWAPW(segment->value);
                        }
                    }
                }
                EntryTableIndex2 entryTableIndex = SWAPW(stateArray[classCode + currentState * nClasses]);
                currentState = processStateEntry(glyphStorage, currGlyph, entryTableIndex);
            }
            break;
        }
        case ltfSegmentArray: {
            printf("Lookup Table Format4: specific interpretation needed!\n");
            break;
        }
        case ltfSingleTable: {
            SingleTableLookupTable *lookupTable6 = (SingleTableLookupTable *) classTable;
            while ((dir == 1 && currGlyph <= glyphCount) || (dir == -1 && currGlyph >= -1)) {
                LookupValue classCode = classCodeOOB;
                if (currGlyph == glyphCount || currGlyph == -1) {
                    // XXX: How do we handle EOT vs. EOL?
                    classCode = classCodeEOT;
                } else {
                    LEGlyphID gid = glyphStorage[currGlyph];
                    TTGlyphID glyphCode = (TTGlyphID) LE_GET_GLYPH(gid);

                    if (glyphCode == 0xFFFF) {
                        classCode = classCodeDEL;
                    } else {
                        const LookupSingle *segment = lookupTable6->lookupSingle(lookupTable6->entries, gid);
                        if (segment != NULL) {
                            classCode = SWAPW(segment->value);
                        }
                    }
                }
                EntryTableIndex2 entryTableIndex = SWAPW(stateArray[classCode + currentState * nClasses]);
                currentState = processStateEntry(glyphStorage, currGlyph, entryTableIndex);
            }
            break;
        }
        case ltfTrimmedArray: {
            TrimmedArrayLookupTable *lookupTable8 = (TrimmedArrayLookupTable *) classTable;
            TTGlyphID firstGlyph = SWAPW(lookupTable8->firstGlyph);
            TTGlyphID lastGlyph  = firstGlyph + SWAPW(lookupTable8->glyphCount);

            while ((dir == 1 && currGlyph <= glyphCount) || (dir == -1 && currGlyph >= -1)) {
                LookupValue classCode = classCodeOOB;
                if (currGlyph == glyphCount || currGlyph == -1) {
                    // XXX: How do we handle EOT vs. EOL?
                    classCode = classCodeEOT;
                } else {
                    TTGlyphID glyphCode = (TTGlyphID) LE_GET_GLYPH(glyphStorage[currGlyph]);
                    if (glyphCode == 0xFFFF) {
                        classCode = classCodeDEL;
                    } else if ((glyphCode >= firstGlyph) && (glyphCode < lastGlyph)) {
                        classCode = SWAPW(lookupTable8->valueArray[glyphCode - firstGlyph]);
                    }
                }
                EntryTableIndex2 entryTableIndex = SWAPW(stateArray[classCode + currentState * nClasses]);
                currentState = processStateEntry(glyphStorage, currGlyph, entryTableIndex);
            }
            break;
        }
        default:
            break;
    }

    endStateTable();
}

U_NAMESPACE_END