/*

 *

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

 *

 */

#include "LETypes.h"

#include "LayoutEngine.h"

#include "ThaiLayoutEngine.h"

#include "ScriptAndLanguageTags.h"

#include "LEGlyphStorage.h"

#include "ThaiShaping.h"

U_NAMESPACE_BEGIN

UOBJECT_DEFINE_RTTI_IMPLEMENTATION(ThaiLayoutEngine)

ThaiLayoutEngine::ThaiLayoutEngine(const LEFontInstance *fontInstance, le_int32 scriptCode, le_int32 languageCode, le_int32 typoFlags)

    : LayoutEngine(fontInstance, scriptCode, languageCode, typoFlags)

{

    fErrorChar = 0x25CC;

    // Figure out which presentation forms the font uses

    if (fontInstance->canDisplay(0x0E64)) {

        // WorldType uses reserved space in Thai block

        fGlyphSet = 0;

    } else if (fontInstance->canDisplay(0xF701)) {

        // Microsoft corporate zone

        fGlyphSet = 1;

        if (!fontInstance->canDisplay(fErrorChar)) {

            fErrorChar = 0xF71B;

        }

    } else if (fontInstance->canDisplay(0xF885)) {

        // Apple corporate zone

        fGlyphSet = 2;

    } else {

        // no presentation forms in the font

        fGlyphSet = 3;

    }

}

ThaiLayoutEngine::~ThaiLayoutEngine()

{

    // nothing to do

}

// Input: characters (0..max provided for context)

// Output: glyphs, char indices

// Returns: the glyph count

// NOTE: this assumes that ThaiShaping::compose will allocate the outChars array...

le_int32 ThaiLayoutEngine::computeGlyphs(const LEUnicode chars[], le_int32 offset, le_int32 count, le_int32 max, le_bool /*rightToLeft*/, LEGlyphStorage &glyphStorage, LEErrorCode &success)

{

    if (LE_FAILURE(success)) {

        return 0;

    }

    if (chars == NULL || offset < 0 || count < 0 || max < 0 || offset >= max || offset + count > max) {

        success = LE_ILLEGAL_ARGUMENT_ERROR;

        return 0;

    }

    LEUnicode *outChars;

    le_int32 glyphCount;

    // This is enough room for the worst-case expansion

    // (it says here...)

    outChars = LE_NEW_ARRAY(LEUnicode, count * 2);

    if (outChars == NULL) {

        success = LE_MEMORY_ALLOCATION_ERROR;

        return 0;

    }

    glyphStorage.allocateGlyphArray(count * 2, FALSE, success);

    if (LE_FAILURE(success)) {

        LE_DELETE_ARRAY(outChars);

        success = LE_MEMORY_ALLOCATION_ERROR;

        return 0;

    }

    glyphCount = ThaiShaping::compose(chars, offset, count, fGlyphSet, fErrorChar, outChars, glyphStorage);

    mapCharsToGlyphs(outChars, 0, glyphCount, FALSE, FALSE, glyphStorage, success);

    LE_DELETE_ARRAY(outChars);

    glyphStorage.adoptGlyphCount(glyphCount);

    return glyphCount;

}

U_NAMESPACE_END