/*
 * 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
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * 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.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
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/*
 *
 * (C) Copyright IBM Corp. 1998-2005 - All Rights Reserved
 *
 */

#ifndef __THAISHAPING_H
#define __THAISHAPING_H

/**
 * \file
 * \internal
 */

#include "LETypes.h"
#include "LEGlyphFilter.h"
#include "OpenTypeTables.h"

U_NAMESPACE_BEGIN

class LEGlyphStorage;

class ThaiShaping /* not : public UObject because all methods are static */ {
public:

    enum {
        // Character classes
        NON =  0,
        CON =  1,
        COA =  2,
        COD =  3,
        LVO =  4,
        FV1 =  5,
        FV2 =  6,
        FV3 =  7,
        BV1 =  8,
        BV2 =  9,
        BDI = 10,
        TON = 11,
        AD1 = 12,
        AD2 = 13,
        AD3 = 14,
        NIK = 15,
        AV1 = 16,
        AV2 = 17,
        AV3 = 18,
        classCount = 19,

        // State Transition actions
        tA  =  0,
        tC  =  1,
        tD  =  2,
        tE  =  3,
        tF  =  4,
        tG  =  5,
        tH  =  6,
        tR  =  7,
        tS  =  8
    };

    struct StateTransition
    {
        le_uint8 nextState;
        le_uint8 action;

        le_uint8 getNextState() { return nextState; };
        le_uint8 getAction() { return action; };
    };

    static le_int32 compose(const LEUnicode *input, le_int32 offset, le_int32 charCount, le_uint8 glyphSet,
        LEUnicode errorChar, LEUnicode *output, LEGlyphStorage &glyphStorage);

private:
    // forbid instantiation
    ThaiShaping();

    static const le_uint8 classTable[];
    static const StateTransition thaiStateTable[][classCount];

    inline static StateTransition getTransition(le_uint8 state, le_uint8 currClass);

    static le_uint8 doTransition(StateTransition transition, LEUnicode currChar, le_int32 inputIndex, le_uint8 glyphSet,
        LEUnicode errorChar, LEUnicode *outputBuffer, LEGlyphStorage &glyphStorage, le_int32 &outputIndex);

    static le_uint8 getNextState(LEUnicode ch, le_uint8 state, le_int32 inputIndex, le_uint8 glyphSet, LEUnicode errorChar,
        le_uint8 &charClass, LEUnicode *output, LEGlyphStorage &glyphStorage, le_int32 &outputIndex);

    static le_bool isLegalHere(LEUnicode ch, le_uint8 prevState);
    static le_uint8 getCharClass(LEUnicode ch);

    static LEUnicode noDescenderCOD(LEUnicode cod, le_uint8 glyphSet);
    static LEUnicode leftAboveVowel(LEUnicode vowel, le_uint8 glyphSet);
    static LEUnicode lowerBelowVowel(LEUnicode vowel, le_uint8 glyphSet);
    static LEUnicode lowerRightTone(LEUnicode tone, le_uint8 glyphSet);
    static LEUnicode lowerLeftTone(LEUnicode tone, le_uint8 glyphSet);
    static LEUnicode upperLeftTone(LEUnicode tone, le_uint8 glyphSet);

};

inline ThaiShaping::StateTransition ThaiShaping::getTransition(le_uint8 state, le_uint8 currClass)
{
    return thaiStateTable[state][currClass];
}

U_NAMESPACE_END
#endif