/*
/ *
 * (C) Copyright IBM Corp. 1998-2015 - All Rights Reserved
 *
 */

#include "LETypes.h"
#include "OpenTypeTables.h"
#include "OpenTypeUtilities.h"
#include "IndicReordering.h"
#include "LEGlyphStorage.h"
#include "MPreFixups.h"

U_NAMESPACE_BEGIN

#define loclFeatureTag LE_LOCL_FEATURE_TAG
#define initFeatureTag LE_INIT_FEATURE_TAG
#define nuktFeatureTag LE_NUKT_FEATURE_TAG
#define akhnFeatureTag LE_AKHN_FEATURE_TAG
#define rphfFeatureTag LE_RPHF_FEATURE_TAG
#define rkrfFeatureTag LE_RKRF_FEATURE_TAG
#define blwfFeatureTag LE_BLWF_FEATURE_TAG
#define halfFeatureTag LE_HALF_FEATURE_TAG
#define pstfFeatureTag LE_PSTF_FEATURE_TAG
#define vatuFeatureTag LE_VATU_FEATURE_TAG
#define presFeatureTag LE_PRES_FEATURE_TAG
#define blwsFeatureTag LE_BLWS_FEATURE_TAG
#define abvsFeatureTag LE_ABVS_FEATURE_TAG
#define pstsFeatureTag LE_PSTS_FEATURE_TAG
#define halnFeatureTag LE_HALN_FEATURE_TAG
#define cjctFeatureTag LE_CJCT_FEATURE_TAG
#define blwmFeatureTag LE_BLWM_FEATURE_TAG
#define abvmFeatureTag LE_ABVM_FEATURE_TAG
#define distFeatureTag LE_DIST_FEATURE_TAG
#define caltFeatureTag LE_CALT_FEATURE_TAG
#define kernFeatureTag LE_KERN_FEATURE_TAG

#define loclFeatureMask 0x80000000UL
#define rphfFeatureMask 0x40000000UL
#define blwfFeatureMask 0x20000000UL
#define halfFeatureMask 0x10000000UL
#define pstfFeatureMask 0x08000000UL
#define nuktFeatureMask 0x04000000UL
#define akhnFeatureMask 0x02000000UL
#define vatuFeatureMask 0x01000000UL
#define presFeatureMask 0x00800000UL
#define blwsFeatureMask 0x00400000UL
#define abvsFeatureMask 0x00200000UL
#define pstsFeatureMask 0x00100000UL 
#define halnFeatureMask 0x00080000UL
#define blwmFeatureMask 0x00040000UL
#define abvmFeatureMask 0x00020000UL
#define distFeatureMask 0x00010000UL
#define initFeatureMask 0x00008000UL
#define cjctFeatureMask 0x00004000UL
#define rkrfFeatureMask 0x00002000UL
#define caltFeatureMask 0x00001000UL
#define kernFeatureMask 0x00000800UL

// Syllable structure bits 
#define baseConsonantMask       0x00000400UL
#define consonantMask           0x00000200UL
#define halfConsonantMask       0x00000100UL
#define rephConsonantMask       0x00000080UL
#define matraMask               0x00000040UL
#define vowelModifierMask       0x00000020UL
#define markPositionMask        0x00000018UL

#define postBasePosition        0x00000000UL
#define preBasePosition         0x00000008UL
#define aboveBasePosition       0x00000010UL
#define belowBasePosition       0x00000018UL

#define repositionedGlyphMask   0x00000002UL

#define basicShapingFormsMask ( loclFeatureMask | nuktFeatureMask | akhnFeatureMask | rkrfFeatureMask | blwfFeatureMask | halfFeatureMask | vatuFeatureMask | cjctFeatureMask )
#define positioningFormsMask ( kernFeatureMask | distFeatureMask | abvmFeatureMask | blwmFeatureMask )
#define presentationFormsMask ( presFeatureMask | abvsFeatureMask | blwsFeatureMask | pstsFeatureMask | halnFeatureMask | caltFeatureMask )


#define C_MALAYALAM_VOWEL_SIGN_U 0x0D41
#define	C_DOTTED_CIRCLE 0x25CC
#define NO_GLYPH 0xFFFF

// Some level of debate as to the proper value for MAX_CONSONANTS_PER_SYLLABLE.  Ticket 5588 states that 4
// is the magic number according to ISCII, but 5 seems to be the more consistent with XP.
#define MAX_CONSONANTS_PER_SYLLABLE 5

#define INDIC_BLOCK_SIZE 0x7F

class IndicReorderingOutput : public UMemory {
private:
    le_int32   fSyllableCount;
    le_int32   fOutIndex;
    LEUnicode *fOutChars;

    LEGlyphStorage &fGlyphStorage;

    LEUnicode   fMpre;
    le_int32    fMpreIndex;

    LEUnicode   fMbelow;
    le_int32    fMbelowIndex;

    LEUnicode   fMabove;
    le_int32    fMaboveIndex;

    LEUnicode   fMpost;
    le_int32    fMpostIndex;

    LEUnicode   fLengthMark;
    le_int32    fLengthMarkIndex;

    LEUnicode   fAlLakuna;
    le_int32    fAlLakunaIndex;

    FeatureMask fMatraFeatures;
    
    le_int32    fMPreOutIndex;
    MPreFixups *fMPreFixups;
    
    LEUnicode   fVMabove;
    LEUnicode   fVMpost;
    le_int32    fVMIndex;
    FeatureMask fVMFeatures;
    
    LEUnicode   fSMabove;
    LEUnicode   fSMbelow;
    le_int32    fSMIndex;
    FeatureMask fSMFeatures;

    LEUnicode   fPreBaseConsonant;
    LEUnicode   fPreBaseVirama;
    le_int32    fPBCIndex;
    FeatureMask fPBCFeatures;

    void saveMatra(LEUnicode matra, le_int32 matraIndex, IndicClassTable::CharClass matraClass)
    {
        // FIXME: check if already set, or if not a matra...
        if (IndicClassTable::isLengthMark(matraClass)) {
            fLengthMark = matra;
            fLengthMarkIndex = matraIndex;
        } else if (IndicClassTable::isAlLakuna(matraClass)) {
            fAlLakuna = matra;
            fAlLakunaIndex = matraIndex;
        } else {
            switch (matraClass & CF_POS_MASK) {
            case CF_POS_BEFORE:
                fMpre = matra;
                fMpreIndex = matraIndex;
                break;
               
            case CF_POS_BELOW:
                fMbelow = matra;
                fMbelowIndex = matraIndex;
                break;
               
            case CF_POS_ABOVE:
                fMabove = matra;
                fMaboveIndex = matraIndex;
                break;
               
            case CF_POS_AFTER:
                fMpost = matra;
                fMpostIndex = matraIndex;
                break;
               
            default:
                // can't get here...
                break;
           }
        }
    }

public:
    IndicReorderingOutput(LEUnicode *outChars, LEGlyphStorage &glyphStorage, MPreFixups *mpreFixups)
        : fSyllableCount(0), fOutIndex(0), fOutChars(outChars), fGlyphStorage(glyphStorage),
          fMpre(0), fMpreIndex(0), fMbelow(0), fMbelowIndex(0), fMabove(0), fMaboveIndex(0),
          fMpost(0), fMpostIndex(0), fLengthMark(0), fLengthMarkIndex(0), fAlLakuna(0), fAlLakunaIndex(0),
          fMatraFeatures(0), fMPreOutIndex(-1), fMPreFixups(mpreFixups),
          fVMabove(0), fVMpost(0), fVMIndex(0), fVMFeatures(0),
          fSMabove(0), fSMbelow(0), fSMIndex(0), fSMFeatures(0),
          fPreBaseConsonant(0), fPreBaseVirama(0), fPBCIndex(0), fPBCFeatures(0)
    {
        // nothing else to do...
    }

    ~IndicReorderingOutput()
    {
        // nothing to do here...
    }

    void reset()
    {
        fSyllableCount += 1;

        fMpre = fMbelow = fMabove = fMpost = fLengthMark = fAlLakuna = 0;
        fMPreOutIndex = -1;
        
        fVMabove = fVMpost  = 0;
        fSMabove = fSMbelow = 0;

        fPreBaseConsonant = fPreBaseVirama = 0;
    }

    void writeChar(LEUnicode ch, le_uint32 charIndex, FeatureMask charFeatures)
    {
        LEErrorCode success = LE_NO_ERROR;

        fOutChars[fOutIndex] = ch;

        fGlyphStorage.setCharIndex(fOutIndex, charIndex, success);
        fGlyphStorage.setAuxData(fOutIndex, charFeatures | (fSyllableCount & LE_GLYPH_GROUP_MASK), success);

        fOutIndex += 1;
    }

    void setFeatures ( le_uint32 charIndex, FeatureMask charFeatures)
    {
        LEErrorCode success = LE_NO_ERROR;

        fGlyphStorage.setAuxData( charIndex, charFeatures, success );

    }

    FeatureMask getFeatures ( le_uint32 charIndex )
    {
        LEErrorCode success = LE_NO_ERROR;
        return fGlyphStorage.getAuxData(charIndex,success);
    }

	void decomposeReorderMatras ( const IndicClassTable *classTable, le_int32 beginSyllable, le_int32 nextSyllable, le_int32 inv_count ) {
		le_int32 i;
        LEErrorCode success = LE_NO_ERROR;

		for ( i = beginSyllable ; i < nextSyllable ; i++ ) {
			if ( classTable->isMatra(fOutChars[i+inv_count])) {
				IndicClassTable::CharClass matraClass = classTable->getCharClass(fOutChars[i+inv_count]);	
				if ( classTable->isSplitMatra(matraClass)) {
					le_int32 saveIndex = fGlyphStorage.getCharIndex(i+inv_count,success);
					le_uint32 saveAuxData = fGlyphStorage.getAuxData(i+inv_count,success);
                    const SplitMatra *splitMatra = classTable->getSplitMatra(matraClass);
                    int j;
                    for (j = 0 ; j < SM_MAX_PIECES && *(splitMatra)[j] != 0 ; j++) {
                        LEUnicode piece = (*splitMatra)[j];
						if ( j == 0 ) {
							fOutChars[i+inv_count] = piece;
							matraClass = classTable->getCharClass(piece);
						} else {
							insertCharacter(piece,i+1+inv_count,saveIndex,saveAuxData);
							nextSyllable++;
						}
 				    }
				}
				
				if ((matraClass & CF_POS_MASK) == CF_POS_BEFORE) {
                    moveCharacter(i+inv_count,beginSyllable+inv_count);
				}
			}
		}
	}

	void moveCharacter( le_int32 fromPosition, le_int32 toPosition ) {
		le_int32 i,saveIndex;
		le_uint32 saveAuxData;
		LEUnicode saveChar = fOutChars[fromPosition];
	    LEErrorCode success = LE_NO_ERROR;
		LEErrorCode success2 = LE_NO_ERROR;
		saveIndex = fGlyphStorage.getCharIndex(fromPosition,success);
        saveAuxData = fGlyphStorage.getAuxData(fromPosition,success);

		if ( fromPosition > toPosition ) {
			for ( i = fromPosition ; i > toPosition ; i-- ) {
				fOutChars[i] = fOutChars[i-1];
				fGlyphStorage.setCharIndex(i,fGlyphStorage.getCharIndex(i-1,success2),success);
				fGlyphStorage.setAuxData(i,fGlyphStorage.getAuxData(i-1,success2), success);

			}
		} else {
			for ( i = fromPosition ; i < toPosition ; i++ ) {
				fOutChars[i] = fOutChars[i+1];
				fGlyphStorage.setCharIndex(i,fGlyphStorage.getCharIndex(i+1,success2),success);
				fGlyphStorage.setAuxData(i,fGlyphStorage.getAuxData(i+1,success2), success);
			}

		}
		fOutChars[toPosition] = saveChar;
		fGlyphStorage.setCharIndex(toPosition,saveIndex,success);
		fGlyphStorage.setAuxData(toPosition,saveAuxData,success);

	}
	void insertCharacter( LEUnicode ch, le_int32 toPosition, le_int32 charIndex, le_uint32 auxData ) {
	    LEErrorCode success = LE_NO_ERROR;
        le_int32 i;
		fOutIndex += 1;

		for ( i = fOutIndex ; i > toPosition ; i--) {
				fOutChars[i] = fOutChars[i-1];
				fGlyphStorage.setCharIndex(i,fGlyphStorage.getCharIndex(i-1,success),success);
				fGlyphStorage.setAuxData(i,fGlyphStorage.getAuxData(i-1,success), success);
		}

		fOutChars[toPosition] = ch;
		fGlyphStorage.setCharIndex(toPosition,charIndex,success);
		fGlyphStorage.setAuxData(toPosition,auxData,success);

	}
	void removeCharacter( le_int32 fromPosition ) {
	    LEErrorCode success = LE_NO_ERROR;
        le_int32 i;
		fOutIndex -= 1;

		for ( i = fromPosition ; i < fOutIndex ; i--) {
				fOutChars[i] = fOutChars[i+1];
				fGlyphStorage.setCharIndex(i,fGlyphStorage.getCharIndex(i+1,success),success);
				fGlyphStorage.setAuxData(i,fGlyphStorage.getAuxData(i+1,success), success);
		}
	}

    le_bool noteMatra(const IndicClassTable *classTable, LEUnicode matra, le_uint32 matraIndex, FeatureMask matraFeatures, le_bool wordStart)
    {
        IndicClassTable::CharClass matraClass = classTable->getCharClass(matra);

        fMatraFeatures  = matraFeatures;

        if (wordStart) {
            fMatraFeatures |= initFeatureMask;
        }

        if (IndicClassTable::isMatra(matraClass)) {
            if (IndicClassTable::isSplitMatra(matraClass)) {
                const SplitMatra *splitMatra = classTable->getSplitMatra(matraClass);
                int i;

                for (i = 0; i < SM_MAX_PIECES && (*splitMatra)[i] != 0; i += 1) {
                    LEUnicode piece = (*splitMatra)[i];
                    IndicClassTable::CharClass pieceClass = classTable->getCharClass(piece);

                    saveMatra(piece, matraIndex, pieceClass);
                }
            } else {
                saveMatra(matra, matraIndex, matraClass);
            }

            return TRUE;
        }

        return FALSE;
    }
    
    void noteVowelModifier(const IndicClassTable *classTable, LEUnicode vowelModifier, le_uint32 vowelModifierIndex, FeatureMask vowelModifierFeatures)
    {
        IndicClassTable::CharClass vmClass = classTable->getCharClass(vowelModifier);
        
        fVMIndex = vowelModifierIndex;
        fVMFeatures  = vowelModifierFeatures;
        
        if (IndicClassTable::isVowelModifier(vmClass)) {
           switch (vmClass & CF_POS_MASK) {
           case CF_POS_ABOVE:
               fVMabove = vowelModifier;
               break;
            
           case CF_POS_AFTER:
               fVMpost = vowelModifier;
               break;
           
           default:
               // FIXME: this is an error...
               break;
           }
        }
    }
    
    void noteStressMark(const IndicClassTable *classTable, LEUnicode stressMark, le_uint32 stressMarkIndex, FeatureMask stressMarkFeatures)
    {
       IndicClassTable::CharClass smClass = classTable->getCharClass(stressMark);
        
        fSMIndex = stressMarkIndex;
        fSMFeatures  = stressMarkFeatures;
        
        if (IndicClassTable::isStressMark(smClass)) {
            switch (smClass & CF_POS_MASK) {
            case CF_POS_ABOVE:
                fSMabove = stressMark;
                break;
            
            case CF_POS_BELOW:
                fSMbelow = stressMark;
                break;
           
            default:
                // FIXME: this is an error...
                break;
           }
        }
    }

    void notePreBaseConsonant(le_uint32 index,LEUnicode PBConsonant, LEUnicode PBVirama, FeatureMask features)
    {
        fPBCIndex = index;
        fPreBaseConsonant = PBConsonant;
        fPreBaseVirama = PBVirama;
        fPBCFeatures = features;
    }

    void noteBaseConsonant()
    {
        if (fMPreFixups != NULL && fMPreOutIndex >= 0) {
            fMPreFixups->add(fOutIndex, fMPreOutIndex);
        }
    }

    // Handles Al-Lakuna in Sinhala split vowels.
    void writeAlLakuna()
    {
        if (fAlLakuna != 0) {
            writeChar(fAlLakuna, fAlLakunaIndex, fMatraFeatures);
        }
    }

    void writeMpre()
    {
        if (fMpre != 0) {
            fMPreOutIndex = fOutIndex;
            writeChar(fMpre, fMpreIndex, fMatraFeatures);
        }
    }

    void writeMbelow()
    {
        if (fMbelow != 0) {
            writeChar(fMbelow, fMbelowIndex, fMatraFeatures);
        }
    }

    void writeMabove()
    {
        if (fMabove != 0) {
            writeChar(fMabove, fMaboveIndex, fMatraFeatures);
        }
    }

    void writeMpost()
    {
        if (fMpost != 0) {
            writeChar(fMpost, fMpostIndex, fMatraFeatures);
        }
    }

    void writeLengthMark()
    {
        if (fLengthMark != 0) {
            writeChar(fLengthMark, fLengthMarkIndex, fMatraFeatures);
        }
    }
    
    void writeVMabove()
    {
        if (fVMabove != 0) {
            writeChar(fVMabove, fVMIndex, fVMFeatures);
        }
    }
        
    void writeVMpost()
    {
        if (fVMpost != 0) {
            writeChar(fVMpost, fVMIndex, fVMFeatures);
        }
    }
    
    void writeSMabove()
    {
        if (fSMabove != 0) {
            writeChar(fSMabove, fSMIndex, fSMFeatures);
        }
    }
    
    void writeSMbelow()
    {
        if (fSMbelow != 0) {
            writeChar(fSMbelow, fSMIndex, fSMFeatures);
        }
    }
    
    void writePreBaseConsonant()
    {
        // The TDIL spec says that consonant + virama + RRA should produce a rakar in Malayalam.  However,
        // it seems that almost none of the fonts for Malayalam are set up to handle this.
        // So, we're going to force the issue here by using the rakar as defined with RA in most fonts.

        if (fPreBaseConsonant == 0x0d31) { // RRA
            fPreBaseConsonant = 0x0d30; // RA
        }
        
        if (fPreBaseConsonant != 0) {
            writeChar(fPreBaseConsonant, fPBCIndex, fPBCFeatures);
            writeChar(fPreBaseVirama,fPBCIndex-1,fPBCFeatures);
        }
    }

    le_int32 getOutputIndex()
    {
        return fOutIndex;
    }
};



// TODO: Find better names for these!
#define tagArray4 (loclFeatureMask | nuktFeatureMask | akhnFeatureMask | vatuFeatureMask | presFeatureMask | blwsFeatureMask | abvsFeatureMask | pstsFeatureMask | halnFeatureMask | blwmFeatureMask | abvmFeatureMask | distFeatureMask)
#define tagArray3 (pstfFeatureMask | tagArray4)
#define tagArray2 (halfFeatureMask | tagArray3)
#define tagArray1 (blwfFeatureMask | tagArray2)
#define tagArray0 (rphfFeatureMask | tagArray1)

static const FeatureMap featureMap[] = {
    {loclFeatureTag, loclFeatureMask},
    {initFeatureTag, initFeatureMask},
    {nuktFeatureTag, nuktFeatureMask},
    {akhnFeatureTag, akhnFeatureMask},
    {rphfFeatureTag, rphfFeatureMask},
    {blwfFeatureTag, blwfFeatureMask},
    {halfFeatureTag, halfFeatureMask},
    {pstfFeatureTag, pstfFeatureMask},
    {vatuFeatureTag, vatuFeatureMask},
    {presFeatureTag, presFeatureMask},
    {blwsFeatureTag, blwsFeatureMask},
    {abvsFeatureTag, abvsFeatureMask},
    {pstsFeatureTag, pstsFeatureMask},
    {halnFeatureTag, halnFeatureMask},
    {blwmFeatureTag, blwmFeatureMask},
    {abvmFeatureTag, abvmFeatureMask},
    {distFeatureTag, distFeatureMask}
};

static const le_int32 featureCount = LE_ARRAY_SIZE(featureMap);

static const FeatureMap v2FeatureMap[] = {
	{loclFeatureTag, loclFeatureMask},
    {nuktFeatureTag, nuktFeatureMask},
    {akhnFeatureTag, akhnFeatureMask},
    {rphfFeatureTag, rphfFeatureMask},
	{rkrfFeatureTag, rkrfFeatureMask}, 
	{blwfFeatureTag, blwfFeatureMask},
    {halfFeatureTag, halfFeatureMask},
    {vatuFeatureTag, vatuFeatureMask},
    {cjctFeatureTag, cjctFeatureMask},
    {presFeatureTag, presFeatureMask},
    {abvsFeatureTag, abvsFeatureMask},
    {blwsFeatureTag, blwsFeatureMask},
    {pstsFeatureTag, pstsFeatureMask},
	{halnFeatureTag, halnFeatureMask}, 
	{caltFeatureTag, caltFeatureMask},
    {kernFeatureTag, kernFeatureMask},
    {distFeatureTag, distFeatureMask},
    {abvmFeatureTag, abvmFeatureMask},
    {blwmFeatureTag, blwmFeatureMask}
};

static const le_int32 v2FeatureMapCount = LE_ARRAY_SIZE(v2FeatureMap);

static const le_int8 stateTable[][CC_COUNT] =
{
//   xx  vm  sm  iv  i2  i3  ct  cn  nu  dv  s1  s2  s3  vr  zw  al
    { 1,  6,  1,  5,  8, 11,  3,  2,  1,  5,  9,  5,  5,  1,  1,  1}, //  0 - ground state
    {-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1}, //  1 - exit state
    {-1,  6,  1, -1, -1, -1, -1, -1, -1,  5,  9,  5,  5,  4, 12, -1}, //  2 - consonant with nukta
    {-1,  6,  1, -1, -1, -1, -1, -1,  2,  5,  9,  5,  5,  4, 12, 13}, //  3 - consonant
    {-1, -1, -1, -1, -1, -1,  3,  2, -1, -1, -1, -1, -1, -1,  7, -1}, //  4 - consonant virama
    {-1,  6,  1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1}, //  5 - dependent vowels
    {-1, -1,  1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1}, //  6 - vowel mark
    {-1, -1, -1, -1, -1, -1,  3,  2, -1, -1, -1, -1, -1, -1, -1, -1}, //  7 - consonant virama ZWJ, consonant ZWJ virama
    {-1,  6,  1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,  4, -1, -1}, //  8 - independent vowels that can take a virama
    {-1,  6,  1, -1, -1, -1, -1, -1, -1, -1, -1, 10,  5, -1, -1, -1}, //  9 - first part of split vowel
    {-1,  6,  1, -1, -1, -1, -1, -1, -1, -1, -1, -1,  5, -1, -1, -1}, // 10 - second part of split vowel
    {-1,  6,  1, -1, -1, -1, -1, -1, -1,  5,  9,  5,  5,  4, -1, -1}, // 11 - independent vowels that can take an iv
    {-1, -1,  1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,  7, -1,  7}, // 12 - consonant ZWJ (TODO: Take everything else that can be after a consonant?)
    {-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,  7, -1}  // 13 - consonant al-lakuna ZWJ consonant
};


const FeatureMap *IndicReordering::getFeatureMap(le_int32 &count)
{
    count = featureCount;

    return featureMap;
}

const FeatureMap *IndicReordering::getv2FeatureMap(le_int32 &count)
{
    count = v2FeatureMapCount;

    return v2FeatureMap;
}

le_int32 IndicReordering::findSyllable(const IndicClassTable *classTable, const LEUnicode *chars, le_int32 prev, le_int32 charCount)
{
    le_int32 cursor = prev;
    le_int8 state = 0;
    le_int8 consonant_count = 0;

    while (cursor < charCount) {
        IndicClassTable::CharClass charClass = classTable->getCharClass(chars[cursor]);
        
        if ( IndicClassTable::isConsonant(charClass) ) {
            consonant_count++;
            if ( consonant_count > MAX_CONSONANTS_PER_SYLLABLE ) {
                break;
            }
        }

        state = stateTable[state][charClass & CF_CLASS_MASK];

        if (state < 0) {
            break;
        }

        cursor += 1;
    }

    return cursor;
}

le_int32 IndicReordering::reorder(const LEUnicode *chars, le_int32 charCount, le_int32 scriptCode,
                                  LEUnicode *outChars, LEGlyphStorage &glyphStorage,
                                  MPreFixups **outMPreFixups, LEErrorCode& success)
{
    if (LE_FAILURE(success)) {
        return 0;
    }

    MPreFixups *mpreFixups = NULL;
    const IndicClassTable *classTable = IndicClassTable::getScriptClassTable(scriptCode);

    if (classTable==NULL) {
        success = LE_INTERNAL_ERROR;
        return 0;
    }

    if (classTable->scriptFlags & SF_MPRE_FIXUP) {
        mpreFixups = new MPreFixups(charCount);
        if (mpreFixups == NULL) { 
            success = LE_MEMORY_ALLOCATION_ERROR;
            return 0;
        }
    }

    IndicReorderingOutput output(outChars, glyphStorage, mpreFixups);
    le_int32 i, prev = 0;
    le_bool lastInWord = FALSE;

    while (prev < charCount) {
        le_int32 syllable = findSyllable(classTable, chars, prev, charCount);
        le_int32 matra, markStart = syllable;

        output.reset();
        
        if (classTable->isStressMark(chars[markStart - 1])) {
            markStart -= 1;
            output.noteStressMark(classTable, chars[markStart], markStart, tagArray1);
        }
        
        if (markStart != prev && classTable->isVowelModifier(chars[markStart - 1])) {
            markStart -= 1;
            output.noteVowelModifier(classTable, chars[markStart], markStart, tagArray1);
        }

        matra = markStart - 1;

        while (output.noteMatra(classTable, chars[matra], matra, tagArray1, !lastInWord) && matra != prev) {
            matra -= 1;
        }

        lastInWord = TRUE;

        switch (classTable->getCharClass(chars[prev]) & CF_CLASS_MASK) {
        case CC_RESERVED:
            lastInWord = FALSE;
            /* fall through */

        case CC_INDEPENDENT_VOWEL:
        case CC_ZERO_WIDTH_MARK:
            for (i = prev; i < syllable; i += 1) {
                output.writeChar(chars[i], i, tagArray1);
            }

            break;

        case CC_AL_LAKUNA:
        case CC_NUKTA:
            output.writeChar(C_DOTTED_CIRCLE, prev, tagArray1);
            output.writeChar(chars[prev], prev, tagArray1);
            break;

        case CC_VIRAMA:
            // A lone virama is illegal unless it follows a
            // MALAYALAM_VOWEL_SIGN_U. Such a usage is called
            // "samvruthokaram".
            if (chars[prev - 1] != C_MALAYALAM_VOWEL_SIGN_U) {
                output.writeChar(C_DOTTED_CIRCLE, prev, tagArray1);
            }

            output.writeChar(chars[prev], prev, tagArray1);
            break;

        case CC_DEPENDENT_VOWEL:
        case CC_SPLIT_VOWEL_PIECE_1:
        case CC_SPLIT_VOWEL_PIECE_2:
        case CC_SPLIT_VOWEL_PIECE_3:
        case CC_VOWEL_MODIFIER:
        case CC_STRESS_MARK:
            output.writeMpre();

            output.writeChar(C_DOTTED_CIRCLE, prev, tagArray1);

            output.writeMbelow();
            output.writeSMbelow();
            output.writeMabove();

            if ((classTable->scriptFlags & SF_MATRAS_AFTER_BASE) != 0) {
                output.writeMpost();
            }

            if ((classTable->scriptFlags & SF_REPH_AFTER_BELOW) != 0) {
                output.writeVMabove();
                output.writeSMabove(); // FIXME: there are no SM's in these scripts...
            }

            if ((classTable->scriptFlags & SF_MATRAS_AFTER_BASE) == 0) {
                output.writeMpost();
            }

            output.writeLengthMark();
            output.writeAlLakuna();

            if ((classTable->scriptFlags & SF_REPH_AFTER_BELOW) == 0) {
                output.writeVMabove();
                output.writeSMabove();
            }

            output.writeVMpost();
            break;

        case CC_INDEPENDENT_VOWEL_2:
        case CC_INDEPENDENT_VOWEL_3:
        case CC_CONSONANT:
        case CC_CONSONANT_WITH_NUKTA:
        {
            le_uint32 length = markStart - prev;
            le_int32  lastConsonant = markStart - 1;
            le_int32  baseLimit = prev;

            // Check for REPH at front of syllable
            if (length > 2 && classTable->isReph(chars[prev]) && classTable->isVirama(chars[prev + 1]) && chars[prev + 2] != C_SIGN_ZWNJ) {
                baseLimit += 2;

                // Check for eyelash RA, if the script supports it
                if ((classTable->scriptFlags & SF_EYELASH_RA) != 0 &&
                    chars[baseLimit] == C_SIGN_ZWJ) {
                    if (length > 3) {
                        baseLimit += 1;
                    } else {
                        baseLimit -= 2;
                    }
                }
            }

            while (lastConsonant > baseLimit && !classTable->isConsonant(chars[lastConsonant])) {
                lastConsonant -= 1;
            }

            
            IndicClassTable::CharClass charClass = CC_RESERVED;
            IndicClassTable::CharClass nextClass = CC_RESERVED;
            le_int32 baseConsonant = lastConsonant;
            le_int32 postBase = lastConsonant + 1;
            le_int32 postBaseLimit = classTable->scriptFlags & SF_POST_BASE_LIMIT_MASK;
            le_bool  seenVattu = FALSE;
            le_bool  seenBelowBaseForm = FALSE;
            le_bool  seenPreBaseForm = FALSE;
            le_bool  hasNukta = FALSE;
            le_bool  hasBelowBaseForm = FALSE;
            le_bool  hasPostBaseForm = FALSE;
            le_bool  hasPreBaseForm = FALSE;

            if (postBase < markStart && classTable->isNukta(chars[postBase])) {
                charClass = CC_NUKTA;
                postBase += 1;
            }

            while (baseConsonant > baseLimit) {
                nextClass = charClass;
                hasNukta  = IndicClassTable::isNukta(nextClass);
                charClass = classTable->getCharClass(chars[baseConsonant]);

                hasBelowBaseForm = IndicClassTable::hasBelowBaseForm(charClass) && !hasNukta;
                hasPostBaseForm  = IndicClassTable::hasPostBaseForm(charClass)  && !hasNukta;
                hasPreBaseForm = IndicClassTable::hasPreBaseForm(charClass) && !hasNukta;

                if (IndicClassTable::isConsonant(charClass)) {
                    if (postBaseLimit == 0 || seenVattu ||
                        (baseConsonant > baseLimit && !classTable->isVirama(chars[baseConsonant - 1])) ||
                        !(hasBelowBaseForm || hasPostBaseForm || hasPreBaseForm)) {
                        break;
                    }

                    // Note any pre-base consonants
                    if ( baseConsonant == lastConsonant && lastConsonant > 0 && 
                         hasPreBaseForm && classTable->isVirama(chars[baseConsonant - 1])) {
                        output.notePreBaseConsonant(lastConsonant,chars[lastConsonant],chars[lastConsonant-1],tagArray2);
                        seenPreBaseForm = TRUE;
   
                    }
                    // consonants with nuktas are never vattus
                    seenVattu = IndicClassTable::isVattu(charClass) && !hasNukta;

                    // consonants with nuktas never have below- or post-base forms
                    if (hasPostBaseForm) {
                        if (seenBelowBaseForm) {
                            break;
                        }

                        postBase = baseConsonant;
                    } else if (hasBelowBaseForm) {
                        seenBelowBaseForm = TRUE;
                    }

                    postBaseLimit -= 1;
                }

                baseConsonant -= 1;
            }

            // Write Mpre
            output.writeMpre();

            // Write eyelash RA
            // NOTE: baseLimit == prev + 3 iff eyelash RA present...
            if (baseLimit == prev + 3) {
                output.writeChar(chars[prev], prev, tagArray2);
                output.writeChar(chars[prev + 1], prev + 1, tagArray2);
                output.writeChar(chars[prev + 2], prev + 2, tagArray2);
            }

            // write any pre-base consonants
            output.writePreBaseConsonant();

            le_bool supressVattu = TRUE;

            for (i = baseLimit; i < baseConsonant; i += 1) {
                LEUnicode ch = chars[i];
                // Don't put 'pstf' or 'blwf' on anything before the base consonant.
                FeatureMask features = tagArray1 & ~( pstfFeatureMask | blwfFeatureMask );

                charClass = classTable->getCharClass(ch);
                nextClass = classTable->getCharClass(chars[i + 1]);
                hasNukta  = IndicClassTable::isNukta(nextClass);

                if (IndicClassTable::isConsonant(charClass)) {
                    if (IndicClassTable::isVattu(charClass) && !hasNukta && supressVattu) {
                        features = tagArray4;
                    }

                    supressVattu = IndicClassTable::isVattu(charClass) && !hasNukta;
                } else if (IndicClassTable::isVirama(charClass) && chars[i + 1] == C_SIGN_ZWNJ)
                {
                    features = tagArray4;
                }

                output.writeChar(ch, i, features);
            }

            le_int32 bcSpan = baseConsonant + 1;

            if (bcSpan < markStart && classTable->isNukta(chars[bcSpan])) {
                bcSpan += 1;
            }

            if (baseConsonant == lastConsonant && bcSpan < markStart &&
                 (classTable->isVirama(chars[bcSpan]) || classTable->isAlLakuna(chars[bcSpan]))) {
                bcSpan += 1;

                if (bcSpan < markStart && chars[bcSpan] == C_SIGN_ZWNJ) {
                    bcSpan += 1;
                }
            }

            // note the base consonant for post-GSUB fixups
            output.noteBaseConsonant();

            // write base consonant
            for (i = baseConsonant; i < bcSpan; i += 1) {
                output.writeChar(chars[i], i, tagArray4);
            }

            if ((classTable->scriptFlags & SF_MATRAS_AFTER_BASE) != 0) {
                output.writeMbelow();
                output.writeSMbelow(); // FIXME: there are no SMs in these scripts...
                output.writeMabove();
                output.writeMpost();
            }

            // write below-base consonants
            if (baseConsonant != lastConsonant && !seenPreBaseForm) {
                for (i = bcSpan + 1; i < postBase; i += 1) {
                    output.writeChar(chars[i], i, tagArray1);
                }

                if (postBase > lastConsonant) {
                    // write halant that was after base consonant
                    output.writeChar(chars[bcSpan], bcSpan, tagArray1);
                }
            }

            // write Mbelow, SMbelow, Mabove
            if ((classTable->scriptFlags & SF_MATRAS_AFTER_BASE) == 0) {
                output.writeMbelow();
                output.writeSMbelow();
                output.writeMabove();
            }

            if ((classTable->scriptFlags & SF_REPH_AFTER_BELOW) != 0) {
                if (baseLimit == prev + 2) {
                    output.writeChar(chars[prev], prev, tagArray0);
                    output.writeChar(chars[prev + 1], prev + 1, tagArray0);
                }

                output.writeVMabove();
                output.writeSMabove(); // FIXME: there are no SM's in these scripts...
            }

            // write post-base consonants
            // FIXME: does this put the right tags on post-base consonants?
            if (baseConsonant != lastConsonant && !seenPreBaseForm) {
                if (postBase <= lastConsonant) {
                    for (i = postBase; i <= lastConsonant; i += 1) {
                        output.writeChar(chars[i], i, tagArray3);
                    }

                    // write halant that was after base consonant
                    output.writeChar(chars[bcSpan], bcSpan, tagArray1);
                }

                // write the training halant, if there is one
                if (lastConsonant < matra && classTable->isVirama(chars[matra])) {
                    output.writeChar(chars[matra], matra, tagArray4);
                }
            }

            // write Mpost
            if ((classTable->scriptFlags & SF_MATRAS_AFTER_BASE) == 0) {
                output.writeMpost();
            }

            output.writeLengthMark();
            output.writeAlLakuna();

            // write reph
            if ((classTable->scriptFlags & SF_REPH_AFTER_BELOW) == 0) {
                if (baseLimit == prev + 2) {
                    output.writeChar(chars[prev], prev, tagArray0);
                    output.writeChar(chars[prev + 1], prev + 1, tagArray0);
                }

                output.writeVMabove();
                output.writeSMabove();
            }

            output.writeVMpost();

            break;
        }

        default:
            break;
        }

        prev = syllable;
    }

    *outMPreFixups = mpreFixups;

    return output.getOutputIndex();
}

void IndicReordering::adjustMPres(MPreFixups *mpreFixups, LEGlyphStorage &glyphStorage, LEErrorCode& success)
{
    if (mpreFixups != NULL) {
        mpreFixups->apply(glyphStorage, success);
        
        delete mpreFixups;
    }
}

void IndicReordering::applyPresentationForms(LEGlyphStorage &glyphStorage, le_int32 count)
{
    LEErrorCode success = LE_NO_ERROR;

//  This sets us up for 2nd pass of glyph substitution as well as setting the feature masks for the
//  GPOS table lookups

    for ( le_int32 i = 0 ; i < count ; i++ ) {
        glyphStorage.setAuxData(i, ( presentationFormsMask | positioningFormsMask ), success);
    }

}
void IndicReordering::finalReordering(LEGlyphStorage &glyphStorage, le_int32 count)
{
    LEErrorCode success = LE_NO_ERROR;

    // Reposition REPH as appropriate

    for ( le_int32 i = 0 ; i < count ; i++ ) {

        le_int32 tmpAuxData = glyphStorage.getAuxData(i,success);
        LEGlyphID tmpGlyph = glyphStorage.getGlyphID(i,success);

        if ( ( tmpGlyph != NO_GLYPH ) && (tmpAuxData & rephConsonantMask) && !(tmpAuxData & repositionedGlyphMask))  {

            le_bool targetPositionFound = false;
            le_int32 targetPosition = i+1;
            le_int32 baseConsonantData;

            while (!targetPositionFound) {
                tmpGlyph = glyphStorage.getGlyphID(targetPosition,success);
                tmpAuxData = glyphStorage.getAuxData(targetPosition,success);

                if ( tmpAuxData & baseConsonantMask ) {
                    baseConsonantData = tmpAuxData;
                    targetPositionFound = true;
                } else {
                    targetPosition++;
                }
            }

            // Make sure we are not putting the reph into an empty hole

            le_bool targetPositionHasGlyph = false;
            while (!targetPositionHasGlyph) {
                tmpGlyph = glyphStorage.getGlyphID(targetPosition,success);
                if ( tmpGlyph != NO_GLYPH ) {
                    targetPositionHasGlyph = true;
                } else {
                    targetPosition--;
                }
            }

            // Make sure that REPH is positioned after any above base or post base matras
            //
            le_bool checkMatraDone = false;
            le_int32 checkMatraPosition = targetPosition+1;
            while ( !checkMatraDone ) {
               tmpAuxData = glyphStorage.getAuxData(checkMatraPosition,success);
               if ( checkMatraPosition >= count || ( (tmpAuxData ^ baseConsonantData) & LE_GLYPH_GROUP_MASK)) {
                   checkMatraDone = true;
                   continue;
               }
               if ( (tmpAuxData & matraMask) && 
                    (((tmpAuxData & markPositionMask) == aboveBasePosition) || 
                      ((tmpAuxData & markPositionMask) == postBasePosition))) {
                   targetPosition = checkMatraPosition;                   
               }
               checkMatraPosition++;
            }
            
            glyphStorage.moveGlyph(i,targetPosition,repositionedGlyphMask);
        }
    }
}


le_int32 IndicReordering::v2process(const LEUnicode *chars, le_int32 charCount, le_int32 scriptCode,
                                  LEUnicode *outChars, LEGlyphStorage &glyphStorage)
{
    const IndicClassTable *classTable = IndicClassTable::getScriptClassTable(scriptCode);
    if (classTable == NULL) {
        return 0;
    }

    DynamicProperties dynProps[INDIC_BLOCK_SIZE];
    IndicReordering::getDynamicProperties(dynProps,classTable);

    IndicReorderingOutput output(outChars, glyphStorage, NULL);
    le_int32 i, firstConsonant, baseConsonant, secondConsonant, inv_count = 0, beginSyllable = 0;
    //le_bool lastInWord = FALSE;

    while (beginSyllable < charCount) {
        le_int32 nextSyllable = findSyllable(classTable, chars, beginSyllable, charCount);

        output.reset();

		// Find the First Consonant
		for ( firstConsonant = beginSyllable ; firstConsonant < nextSyllable ; firstConsonant++ ) {
			 if ( classTable->isConsonant(chars[firstConsonant]) ) {
					break;
				}
		}

        // Find the base consonant

        baseConsonant = nextSyllable - 1;
        secondConsonant = firstConsonant;

        // TODO: Use Dynamic Properties for hasBelowBaseForm and hasPostBaseForm()

        while ( baseConsonant > firstConsonant ) {
            if ( classTable->isConsonant(chars[baseConsonant]) && 
                 !classTable->hasBelowBaseForm(chars[baseConsonant]) && 
                 !classTable->hasPostBaseForm(chars[baseConsonant]) ) {
                break;
            }
            else {
                if ( classTable->isConsonant(chars[baseConsonant]) ) {
                    secondConsonant = baseConsonant;
                }
                baseConsonant--;
            }
        }

        // If the syllable starts with Ra + Halant ( in a script that has Reph ) and has more than one
        // consonant, Ra is excluced from candidates for base consonants

        if ( classTable->isReph(chars[beginSyllable]) &&
             beginSyllable+1 < nextSyllable && classTable->isVirama(chars[beginSyllable+1]) &&
             secondConsonant != firstConsonant) {
            baseConsonant = secondConsonant;                     
        }

	    // Populate the output 
		for ( i = beginSyllable ; i < nextSyllable ; i++ ) {

            // Handle invalid combinartions

            if ( classTable->isVirama(chars[beginSyllable]) || 
			     classTable->isMatra(chars[beginSyllable]) ||
			     classTable->isVowelModifier(chars[beginSyllable]) ||
			     classTable->isNukta(chars[beginSyllable]) ) {
                     output.writeChar(C_DOTTED_CIRCLE,beginSyllable,basicShapingFormsMask);
                     inv_count++;
            }
             output.writeChar(chars[i],i, basicShapingFormsMask);

        }

        // Adjust features and set syllable structure bits

        for ( i = beginSyllable ; i < nextSyllable ; i++ ) {

            FeatureMask outMask = output.getFeatures(i+inv_count);
            FeatureMask saveMask = outMask;

            // Since reph can only validly occur at the beginning of a syllable
            // We only apply it to the first 2 characters in the syllable, to keep it from
            // conflicting with other features ( i.e. rkrf )

            // TODO : Use the dynamic property for determining isREPH
            if ( i == beginSyllable && i < baseConsonant && classTable->isReph(chars[i]) &&
                 i+1 < nextSyllable && classTable->isVirama(chars[i+1])) {
                outMask |= rphfFeatureMask;
                outMask |= rephConsonantMask;
                output.setFeatures(i+1+inv_count,outMask);

            }

            if ( i == baseConsonant ) {
                outMask |= baseConsonantMask;
            }

            if ( classTable->isMatra(chars[i])) {
                    outMask |= matraMask;
                    if ( classTable->hasAboveBaseForm(chars[i])) {
                        outMask |= aboveBasePosition;
                    } else if ( classTable->hasBelowBaseForm(chars[i])) {
                        outMask |= belowBasePosition;
                    }
            }

            // Don't apply half form to virama that stands alone at the end of a syllable
            // to prevent half forms from forming when syllable ends with virama

            if ( classTable->isVirama(chars[i]) && (i+1 == nextSyllable) ) {
                outMask ^= halfFeatureMask;
                if ( classTable->isConsonant(chars[i-1]) ) {
                    FeatureMask tmp = output.getFeatures(i-1+inv_count);
                    tmp ^= halfFeatureMask;
                    output.setFeatures(i-1+inv_count,tmp);
                }
            }

            if ( outMask != saveMask ) {
                output.setFeatures(i+inv_count,outMask);
            }
		}

	    output.decomposeReorderMatras(classTable,beginSyllable,nextSyllable,inv_count);

        beginSyllable = nextSyllable;   
	}


    return output.getOutputIndex();
}


void IndicReordering::getDynamicProperties( DynamicProperties *, const IndicClassTable *classTable ) {


    LEUnicode currentChar;
    LEUnicode workChars[2];
    LEGlyphStorage workGlyphs;

    IndicReorderingOutput workOutput(workChars, workGlyphs, NULL);

    //le_int32 offset = 0;

#if 0
// TODO:  Should this section of code have actually been doing something?
    // First find the relevant virama for the script we are dealing with
    LEUnicode virama;
    for ( currentChar = classTable->firstChar ; currentChar <= classTable->lastChar ; currentChar++ ) {
        if ( classTable->isVirama(currentChar)) {
            virama = currentChar;
            break;
        }
    }
#endif

    for ( currentChar = classTable->firstChar ; currentChar <= classTable->lastChar ; currentChar++ ) {
        if ( classTable->isConsonant(currentChar)) {
            workOutput.reset();
        }
    }


}

U_NAMESPACE_END
