/*

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * particular file as subject to the "Classpath" exception as provided

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 *

 */

/*

 *

 * (C) Copyright IBM Corp. 1998-2005 - All Rights Reserved

 *

 */

#include "LETypes.h"

#include "OpenTypeTables.h"

#include "ArabicShaping.h"

#include "LEGlyphStorage.h"

#include "ClassDefinitionTables.h"

U_NAMESPACE_BEGIN

// This table maps Unicode joining types to

// ShapeTypes.

const ArabicShaping::ShapeType ArabicShaping::shapeTypes[] =

{

    ArabicShaping::ST_NOSHAPE_NONE, // [U]

    ArabicShaping::ST_NOSHAPE_DUAL, // [C]

    ArabicShaping::ST_DUAL,         // [D]

    ArabicShaping::ST_LEFT,         // [L]

    ArabicShaping::ST_RIGHT,        // [R]

    ArabicShaping::ST_TRANSPARENT   // [T]

};

/*

    shaping array holds types for Arabic chars between 0610 and 0700

    other values are either unshaped, or transparent if a mark or format

    code, except for format codes 200c (zero-width non-joiner) and 200d

    (dual-width joiner) which are both unshaped and non_joining or

    dual-joining, respectively.

*/

ArabicShaping::ShapeType ArabicShaping::getShapeType(LEUnicode c)

{

    const ClassDefinitionTable *joiningTypes = (const ClassDefinitionTable *) ArabicShaping::shapingTypeTable;

    le_int32 joiningType = joiningTypes->getGlyphClass(c);

    if (joiningType >= 0 && joiningType < ArabicShaping::JT_COUNT) {

        return ArabicShaping::shapeTypes[joiningType];

    }

    return ArabicShaping::ST_NOSHAPE_NONE;

}

#define isolFeatureTag LE_ISOL_FEATURE_TAG

#define initFeatureTag LE_INIT_FEATURE_TAG

#define mediFeatureTag LE_MEDI_FEATURE_TAG

#define finaFeatureTag LE_FINA_FEATURE_TAG

#define ligaFeatureTag LE_LIGA_FEATURE_TAG

#define msetFeatureTag LE_MSET_FEATURE_TAG

#define markFeatureTag LE_MARK_FEATURE_TAG

#define ccmpFeatureTag LE_CCMP_FEATURE_TAG

#define rligFeatureTag LE_RLIG_FEATURE_TAG

#define caltFeatureTag LE_CALT_FEATURE_TAG

#define dligFeatureTag LE_DLIG_FEATURE_TAG

#define cswhFeatureTag LE_CSWH_FEATURE_TAG

#define cursFeatureTag LE_CURS_FEATURE_TAG

#define kernFeatureTag LE_KERN_FEATURE_TAG

#define mkmkFeatureTag LE_MKMK_FEATURE_TAG

// NOTE:

// The isol, fina, init and medi features must be

// defined in the above order, and have masks that

// are all in the same nibble.

#define isolFeatureMask 0x80000000UL

#define finaFeatureMask 0x40000000UL

#define initFeatureMask 0x20000000UL

#define mediFeatureMask 0x10000000UL

#define ccmpFeatureMask 0x08000000UL

#define rligFeatureMask 0x04000000UL

#define caltFeatureMask 0x02000000UL

#define ligaFeatureMask 0x01000000UL

#define dligFeatureMask 0x00800000UL

#define cswhFeatureMask 0x00400000UL

#define msetFeatureMask 0x00200000UL

#define cursFeatureMask 0x00100000UL

#define kernFeatureMask 0x00080000UL

#define markFeatureMask 0x00040000UL

#define mkmkFeatureMask 0x00020000UL

#define ISOL_FEATURES (isolFeatureMask | ligaFeatureMask | msetFeatureMask | markFeatureMask | ccmpFeatureMask | rligFeatureMask | caltFeatureMask | dligFeatureMask | cswhFeatureMask | cursFeatureMask | kernFeatureMask | mkmkFeatureMask)

#define SHAPE_MASK 0xF0000000UL

static const FeatureMap featureMap[] = {

    {ccmpFeatureTag, ccmpFeatureMask},

    {isolFeatureTag, isolFeatureMask},

    {finaFeatureTag, finaFeatureMask},

    {mediFeatureTag, mediFeatureMask},

    {initFeatureTag, initFeatureMask},

    {rligFeatureTag, rligFeatureMask},

    {caltFeatureTag, caltFeatureMask},

    {ligaFeatureTag, ligaFeatureMask},

    {dligFeatureTag, dligFeatureMask},

    {cswhFeatureTag, cswhFeatureMask},

    {msetFeatureTag, msetFeatureMask},

    {cursFeatureTag, cursFeatureMask},

    {kernFeatureTag, kernFeatureMask},

    {markFeatureTag, markFeatureMask},

    {mkmkFeatureTag, mkmkFeatureMask}

};

const FeatureMap *ArabicShaping::getFeatureMap(le_int32 &count)

{

    count = LE_ARRAY_SIZE(featureMap);

    return featureMap;

}

void ArabicShaping::adjustTags(le_int32 outIndex, le_int32 shapeOffset, LEGlyphStorage &glyphStorage)

{

    LEErrorCode success = LE_NO_ERROR;

    FeatureMask featureMask = (FeatureMask) glyphStorage.getAuxData(outIndex, success);

    FeatureMask shape = featureMask & SHAPE_MASK;

    shape >>= shapeOffset;

    glyphStorage.setAuxData(outIndex, ((featureMask & ~SHAPE_MASK) | shape), success);

}

void ArabicShaping::shape(const LEUnicode *chars, le_int32 offset, le_int32 charCount, le_int32 charMax,

                          le_bool rightToLeft, LEGlyphStorage &glyphStorage)

{

    // iterate in logical order, store tags in visible order

    //

    // the effective right char is the most recently encountered

    // non-transparent char

    //

    // four boolean states:

    //   the effective right char shapes

    //   the effective right char causes left shaping

    //   the current char shapes

    //   the current char causes right shaping

    //

    // if both cause shaping, then

    //   shaper.shape(errout, 2) (isolate to initial, or final to medial)

    //   shaper.shape(out, 1) (isolate to final)

    ShapeType rightType = ST_NOSHAPE_NONE, leftType = ST_NOSHAPE_NONE;

    LEErrorCode success = LE_NO_ERROR;

    le_int32 i;

    for (i = offset - 1; i >= 0; i -= 1) {

        rightType = getShapeType(chars[i]);

        if (rightType != ST_TRANSPARENT) {

            break;

        }

    }

    for (i = offset + charCount; i < charMax; i += 1) {

        leftType = getShapeType(chars[i]);

        if (leftType != ST_TRANSPARENT) {

            break;

        }

    }

    // erout is effective right logical index

    le_int32 erout = -1;

    le_bool rightShapes = FALSE;

    le_bool rightCauses = (rightType & MASK_SHAPE_LEFT) != 0;

    le_int32 in, e, out = 0, dir = 1;

    if (rightToLeft) {

        out = charCount - 1;

        erout = charCount;

        dir = -1;

    }

    for (in = offset, e = offset + charCount; in < e; in += 1, out += dir) {

        LEUnicode c = chars[in];

        ShapeType t = getShapeType(c);

        glyphStorage.setAuxData(out, ISOL_FEATURES, success);

        if ((t & MASK_TRANSPARENT) != 0) {

            continue;

        }

        le_bool curShapes = (t & MASK_NOSHAPE) == 0;

        le_bool curCauses = (t & MASK_SHAPE_RIGHT) != 0;

        if (rightCauses && curCauses) {

            if (rightShapes) {

                adjustTags(erout, 2, glyphStorage);

            }

            if (curShapes) {

                adjustTags(out, 1, glyphStorage);

            }

        }

        rightShapes = curShapes;

        rightCauses = (t & MASK_SHAPE_LEFT) != 0;

        erout = out;

    }

    if (rightShapes && rightCauses && (leftType & MASK_SHAPE_RIGHT) != 0) {

        adjustTags(erout, 2, glyphStorage);

    }

}

U_NAMESPACE_END