parser.cpp

//=============================================================================
//  BWW to MusicXML converter
//  Part of MusE Score
//  Linux Music Score Editor
//
//  Copyright (C) 2010 Werner Schweer and others
//
//  This program is free software; you can redistribute it and/or modify
//  it under the terms of the GNU General Public License version 2.
//
//  This program 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 for more details.
//
//  You should have received a copy of the GNU General Public License
//  along with this program; if not, write to the Free Software
//  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
//=============================================================================

/**
 \file
 A simple parser for bww files. The file header is handled one line at a time,
 until a line starting with "&" is found. The parser then builds measures from
 uinterrupted sequences of notes.
 */

// #include <iostream>

#include <QtCore/QStringList>
#include <QtCore/QtDebug>
#include <QtCore/QMap>

#include "lexer.h"
#include "parser.h"
#include "writer.h"

// Duration of a whole measure in ticks
static const int WHOLE_MEASURE_DURATION = 192;

/**
 Determine if symbol is part of a note sequence
 */

static bool isNote(Bww::Symbol sym)
{
    return sym == Bww::NOTE
           || sym == Bww::TIE
           || sym == Bww::TRIPLET
           || sym == Bww::GRACE;
}

/**
 Determine if symbol is part of a non-note sequence
 */

static bool isNonNote(Bww::Symbol sym)
{
    return sym == Bww::CLEF
           || sym == Bww::KEY
           || sym == Bww::TSIG
           || sym == Bww::PART
           || sym == Bww::BAR;
}

/**
 Dump beams
 */

static void dumpBeams(QList<Bww::MeasureDescription> const& measures)
{
    for (int j = 0; j < measures.size(); ++j) {
        QString beams;
        QString beamStates;
        QVector<QString> beamList(3);
        for (int i = 0; i < measures.at(j).notes.size(); ++i) {
            QString beam = measures.at(j).notes.at(i).beam;
            if (beam == "") {
                beam = " ";
            }

            beams += beam;
            switch (measures.at(j).notes.at(i).beamState) {
            case Bww::ST_NONE:     beamStates += " ";
                break;
            case Bww::ST_START:    beamStates += "[";
                break;
            case Bww::ST_CONTINUE: beamStates += "_";
                break;
            case Bww::ST_STOP:     beamStates += "]";
                break;
            default:               beamStates += " ";
            }
            for (int k = 0; k < 3; k++) {
                switch (measures.at(j).notes.at(i).beamList.at(k)) {
                case Bww::BM_NONE:          beamList[k] += " ";
                    break;
                case Bww::BM_BEGIN:         beamList[k] += "b";
                    break;
                case Bww::BM_CONTINUE:      beamList[k] += "c";
                    break;
                case Bww::BM_END:           beamList[k] += "e";
                    break;
                case Bww::BM_FORWARD_HOOK:  beamList[k] += ">";
                    break;
                case Bww::BM_BACKWARD_HOOK: beamList[k] += "<";
                    break;
                default:                    beamList[k] += "?";
                }
            }
        }
        qDebug() << "beams measure #" << j + 1 << beams;
        qDebug() << "beams measure #" << j + 1 << beamStates;
        for (int k = 0; k < 3; k++) {
            qDebug() << "beams measure #" << j + 1 << beamList.at(k);
        }
    }
}

/**
 Dump measure contents
 */

static void dumpMeasures(QList<Bww::MeasureDescription> const& measures)
{
    qDebug() << "dumpMeasures #measures" << measures.size()
    ;
    for (int j = 0; j < measures.size(); ++j) {
        qDebug() << "measure #" << j + 1;
        qDebug() << "Measure contents:";
        qDebug() << "mbf:"
                 << "repeatBegin" << measures.at(j).mbf.repeatBegin
                 << "endingFirst" << measures.at(j).mbf.endingFirst
                 << "endingSecond" << measures.at(j).mbf.endingSecond
                 << "firstOfSystem" << measures.at(j).mbf.firstOfSystem
                 << "irregular" << measures.at(j).mbf.irregular
        ;
        for (int i = 0; i < measures.at(j).notes.size(); ++i) {
            qDebug()
                << measures.at(j).notes.at(i).pitch
                << measures.at(j).notes.at(i).beam
                << measures.at(j).notes.at(i).type
                << measures.at(j).notes.at(i).dots
                << measures.at(j).notes.at(i).tieStart
                << measures.at(j).notes.at(i).tieStop
                << measures.at(j).notes.at(i).triplet
                << measures.at(j).notes.at(i).grace
            ;
        }
        qDebug() << "mef:"
                 << "repeatEnd" << measures.at(j).mef.repeatEnd
                 << "endingEnd" << measures.at(j).mef.endingEnd
                 << "lastOfSystem" << measures.at(j).mef.lastOfSystem
                 << "lastOfPart" << measures.at(j).mef.lastOfPart
        ;
        qDebug() << "duration:" << measures.at(j).duration;
    }
}

/**
 Calculate measure durations
 */

static void calculateMeasureDurations(QList<Bww::MeasureDescription>& measures)
{
    for (int j = 0; j < measures.size(); ++j) {
        int measureDuration = 0;
        for (int i = 0; i < measures.at(j).notes.size(); ++i) {
            int ticks = WHOLE_MEASURE_DURATION / measures.at(j).notes.at(i).type.toInt();
            if (measures.at(j).notes.at(i).dots) {
                ticks = 3 * ticks / 2;
            }
            if (measures.at(j).notes.at(i).triplet != Bww::ST_NONE) {
                ticks = 2 * ticks / 3;
            }
            if (measures.at(j).notes.at(i).grace) {
                ticks = 0;                             // grace notes don't count
            }
            measureDuration += ticks;
            qDebug()
                << measures.at(j).notes.at(i).pitch
                << measures.at(j).notes.at(i).beam
                << measures.at(j).notes.at(i).type
                << measures.at(j).notes.at(i).dots
                << measures.at(j).notes.at(i).tieStart
                << measures.at(j).notes.at(i).tieStop
                << measures.at(j).notes.at(i).triplet
                << measures.at(j).notes.at(i).grace
                << "->" << ticks
            ;
        }
        qDebug() << "measureDuration:" << measureDuration;
        measures[j].duration = measureDuration;
    }
}

/**
 Determine time signature
 */

static void determineTimesig(QList<Bww::MeasureDescription> const& measures, int& beats, int& beat)
{
    QMap<int, int> map;
    for (int j = 0; j < measures.size(); ++j) {
        int dur = measures[j].duration;
        if (map.contains(dur)) {
            map[dur]++;
        } else {
            map.insert(dur, 1);
        }
    }
    // determine most common duration
    int commonDur = 0;
    int max = 0;
    QMap<int, int>::const_iterator i = map.constBegin();
    while (i != map.constEnd())
    {
        qDebug() << "measureDurations:" << i.key() << i.value();
        if (i.value() > max) {
            commonDur = i.key();
            max = i.value();
        }
        ++i;
    }
    qDebug() << "measureDuration commonDur:" << commonDur << "max:" << max;
    // determine time signature
    beat = 4;
    beats = 0;
    int divisor = WHOLE_MEASURE_DURATION / 4;
    for (; beat < 64; beat *= 2, divisor /= 2) {
        if ((commonDur % divisor) == 0) {
            beats = commonDur / divisor;
            qDebug()
                << "measureDuration found beat:" << beat
                << "beats:" << beats
                << "divisor:" << divisor
            ;
            return;
        }
    }
    // could not determine time signature, set default
    beat = 4;
    beats = 4;
}

/**
 Find irregular measures
 */

static void findIrregularMeasures(QList<Bww::MeasureDescription>& measures, int beats, int beat)
{
    qDebug() << "findIrregularMeasures" << measures.size()
             << "beats" << beats
             << "beat" << beat
    ;

    int normalDuration = WHOLE_MEASURE_DURATION * beats / beat;

    // need at least one measure
    if (measures.size() == 0) {
        return;
    }

    // if the first measure is shorter that normal, it is irregular
    if (measures.at(0).duration < normalDuration) {
        measures[0].mbf.irregular = true;
    }

    for (int j = 1; j < measures.size(); ++j) {
        // the second measure of a pair where the sum of their duration adds up
        // to the normal duration is also irregular
        const int d1 = measures.at(j - 1).duration;
        const int d2 = measures.at(j).duration;
        if (d1 > 0 && d2 > 0 && (d1 + d2) == normalDuration) {
            measures[j].mbf.irregular = true;
        }
    }
}

/**
 Set mef.lastOfPart flag on last measure
 */

static void setLastOfPart(QList<Bww::MeasureDescription>& measures)
{
    qDebug() << "dumpMeasures #measures" << measures.size()
    ;

    // need at least one measure
    if (measures.size() == 0) {
        return;
    }

    // set lastOfPart flag on last measure
    int j = measures.size() - 1;
    measures[j].mef.lastOfPart = true;
}

static QString findNextNextNoteBeam(QList<Bww::MeasureDescription> const& measures, int measureNr, int noteNr)
{
    for (int i = noteNr + 1; i < measures.at(measureNr).notes.size(); ++i) {
        if (measures.at(measureNr).notes.at(i).grace) {
            // ignore grace notes
            continue;
        }
        return measures.at(measureNr).notes.at(i).beam;
    }
    return " "; // no next non-grace note found
}

static int type2beams(QString type)
{
    if (type == "8") {
        return 1;
    } else if (type == "16") {
        return 2;
    } else if (type == "32") {
        return 3;
    } else {
        return 0;
    }
}

static void calculateHigherBeamStates(Bww::MeasureDescription& m)
{
    qDebug() << "calculateHigherBeamStates";
    for (int i = 0; i < m.notes.size(); ++i) {
        qDebug()
            << m.notes.at(i).pitch
            << m.notes.at(i).beam
            << m.notes.at(i).type
            << m.notes.at(i).dots
            << m.notes.at(i).tieStart
            << m.notes.at(i).tieStop
            << m.notes.at(i).triplet
            << m.notes.at(i).grace
        ;

        if (m.notes.at(i).grace) {
            // just copy beamList[0] into beamList[1] and beamList[2]
            m.notes[i].beamList[1] = m.notes.at(i).beamList[0];
            m.notes[i].beamList[2] = m.notes.at(i).beamList[0];
        } else {
            int blp = -1; // beam level previous chord
            int blc = -1; // beam level current chord
            int bln = -1; // beam level next chord

            // find beam level current note
            blc = type2beams(m.notes.at(i).type);
            if (blc == 0) {
                continue; // note does not have a beam
            }
            // find beam level previous note
            if (m.notes.at(i).beamList[0] == Bww::BM_CONTINUE
                || m.notes.at(i).beamList[0] == Bww::BM_END) {
                for (int j = i - 1; blp == -1 && j >= 0; --j) {
                    if (m.notes.at(j).grace) {
                        continue; // ignore grace notes
                    }
                    blp = type2beams(m.notes.at(j).type);
                }
            }

            // find beam level next note
            if (m.notes.at(i).beamList[0] == Bww::BM_BEGIN
                || m.notes.at(i).beamList[0] == Bww::BM_CONTINUE) {
                for (int j = i + 1; bln == -1 && j < m.notes.size(); ++j) {
                    if (m.notes.at(j).grace) {
                        continue; // ignore grace notes
                    }
                    bln = type2beams(m.notes.at(j).type);
                }
            }

            qDebug()
                << "blp" << blp
                << "blc" << blc
                << "bln" << bln;
            for (int j = 2; j <= blc; ++j) {
                Bww::BeamType bt = Bww::BM_NONE;
                if (blp < j && bln >= j) {
                    bt = Bww::BM_BEGIN;
                } else if (blp < j && bln < j) {
                    if (bln > 0) {
                        bt = Bww::BM_FORWARD_HOOK;
                    } else if (blp > 0) {
                        bt = Bww::BM_BACKWARD_HOOK;
                    }
                } else if (blp >= j && bln < j) {
                    bt = Bww::BM_END;
                } else if (blp >= j && bln >= j) {
                    bt = Bww::BM_CONTINUE;
                }
                m.notes[i].beamList[j - 1] = bt;
                qDebug() << "beamList" << j - 1 << "=" << bt;
            }
        } // else
    } // for (int i = 0; i < m.notes.size(); ++i)
}

/**
 Determine all beam states.
 First for normal notes convert "r" and "l" in notes.beam into BM_BEGIN,
 BM_CONTINUE and BM_END in notes.beamList[0]. For grace notes "b", "c" and
 "e" can be directly converted into the corresponding beam states in
 notes.beamList[0].
 Then calculate the higher level beams.
 */

static void determineBeamStates(QList<Bww::MeasureDescription>& measures)
{
    enum State {
        NONE, LEFT, RIGHT
    };
    for (int j = 0; j < measures.size(); ++j) {
        State state = NONE;
        for (int i = 0; i < measures.at(j).notes.size(); ++i) {
            QString beam = measures.at(j).notes.at(i).beam;
            // handle normal notes
            if (beam == "") {
                measures[j].notes[i].beamState = Bww::ST_NONE;
                measures[j].notes[i].beamList[0] = Bww::BM_NONE;
                state = NONE;
            } else if (beam == "r") {
                if (state == NONE) {
                    measures[j].notes[i].beamState = Bww::ST_START;
                    measures[j].notes[i].beamList[0] = Bww::BM_BEGIN;
                    state = LEFT; // now in left part of beam
                } else if (state == LEFT) {
                    measures[j].notes[i].beamState = Bww::ST_CONTINUE;
                    measures[j].notes[i].beamList[0] = Bww::BM_CONTINUE;
                } else if (state == RIGHT) {
                    // shouldn't happen TODO report (internal?) error
                }
            } else if (beam == "l") {
                if (state == NONE) {
                    // shouldn't happen TODO report error
                } else if (state == LEFT || state == RIGHT) {
                    // if the beam does not end here (next note has beam "l")
                    // then beamState is CONTINUE else STOP
                    if (findNextNextNoteBeam(measures, j, i) == "l") {
                        measures[j].notes[i].beamState = Bww::ST_CONTINUE;
                        measures[j].notes[i].beamList[0] = Bww::BM_CONTINUE;
                        state = RIGHT; // now in right part of beam
                    } else {
                        measures[j].notes[i].beamState = Bww::ST_STOP;
                        measures[j].notes[i].beamList[0] = Bww::BM_END;
                        state = NONE; // now in right part of beam
                    }
                }
            }
            // handle grace notes
            else if (beam == "b") {
                measures[j].notes[i].beamList[0] = Bww::BM_BEGIN;
            } else if (beam == "c") {
                measures[j].notes[i].beamList[0] = Bww::BM_CONTINUE;
            } else if (beam == "e") {
                measures[j].notes[i].beamList[0] = Bww::BM_END;
            }
        }
        calculateHigherBeamStates(measures[j]);
    }
}

namespace Bww {
/**
   Parser constructor, using Lexer \a l and Writer \a w.
   */

Parser::Parser(Lexer& l, Writer& w)
    : lex(l),
    wrt(w),
    tempo(0),
    //inMeasure(false),
    //measureNr(0),
    beat(0),
    beats(0),
    tieStart(false),
    inTie(false),
    tripletStart(false),
    inTriplet(false),
    tsigFound(false)
{
    qDebug() << "Parser::Parser()";
}

/**
   Parse the input stream and write result.
   */

void Parser::parse()
{
    // read the header, handling only strings and tune tempo
    while (lex.symType() == COMMENT
           || lex.symType() == STRING
           || lex.symType() == TEMPO)
    {
        if (lex.symType() == STRING) {
            parseString();
        } else if (lex.symType() == TEMPO) {
            parseTempo();
        } else if (lex.symType() == COMMENT) {
            lex.getSym();
        }
    }
    qDebug() << "Parser::parse()"
             << "title:" << title
             << "type:" << type
             << "composer:" << composer
             << "footer:" << footer
    ;
    wrt.header(title, type, composer, footer, tempo);

    // read the actual music
    if (lex.symType() != CLEF) {
        errorHandler("clef ('&') expected");
    }
    while (lex.symType() != NONE)
    {
        if (isNonNote(lex.symType())) {
            parseSeqNonNotes();
        } else if (isNote(lex.symType())) {
            parseSeqNotes();
        } else if (lex.symType() == UNKNOWN) {
            errorHandler("unknown symbol '" + lex.symValue() + "'");
            lex.getSym();
        } else {
            // others not implemented yet: silently ignored
            lex.getSym();
        }
    }

    qDebug() << "Parser::parse() finished, #measures" << measures.size()
    ;

    calculateMeasureDurations(measures);
    if (!tsigFound) {
        determineTimesig(measures, beats, beat);
        wrt.tsig(beats, beat);
    }
    findIrregularMeasures(measures, beats, beat);
    determineBeamStates(measures);
    setLastOfPart(measures);
    dumpMeasures(measures);
    dumpBeams(measures);

    for (int j = 0; j < measures.size(); ++j) {
        wrt.beginMeasure(measures.at(j).mbf);
        for (int i = 0; i < measures.at(j).notes.size(); ++i) {
            wrt.note(measures.at(j).notes.at(i).pitch,
                     measures.at(j).notes.at(i).beamList,
                     measures.at(j).notes.at(i).type,
                     measures.at(j).notes.at(i).dots,
                     measures.at(j).notes.at(i).tieStart,
                     measures.at(j).notes.at(i).tieStop,
                     measures.at(j).notes.at(i).triplet,
                     measures.at(j).notes.at(i).grace
                     );
        }
        wrt.endMeasure(measures.at(j).mef);
    }

    // trailer
    wrt.trailer();
}

/**
   Display error \a s.
   */

void Parser::errorHandler(QString /*s*/)
{
#if 0 // WS
    std::cerr << "Parse error line "
              << lex.symLineNumber() + 1
              << ": "
              << qPrintable(s)
              << std::endl;
#endif
}

/**
   Parse a bww bar symbol.
   */

void Parser::parseBar(Bww::MeasureEndFlags& mef)
{
    qDebug() << "Parser::parseBar() value:" << qPrintable(lex.symValue());
    if (lex.symValue() == "!!t") {
        mef.doubleBarLine = true;
    }
    lex.getSym();
}

/**
   Parse a bww note.
   */

void Parser::parseNote()
{
    qDebug() << "Parser::parseNote() value:" << qPrintable(lex.symValue());

    QRegExp rNotes("(LG|LA|[B-F]|HG|HA)([lr]?)_(1|2|4|8|16|32)");

    QStringList caps;
    if (rNotes.exactMatch(lex.symValue())) {
        caps = rNotes.capturedTexts();
        qDebug() << " match" << caps.size();
        if (caps.size() == 4) {
            qDebug()
                << "caps[1]" << caps.at(1)
                << "caps[2]" << caps.at(2)
                << "caps[3]" << caps.at(3)
            ;
        }
    }
    lex.getSym();

    int dots = 0;
    bool tieStop = false;
    if (tieStart) {
        inTie = true;
    }
    bool tripletStop = false;
    if (tripletStart) {
        inTriplet = true;
    }
    if (lex.symType() == DOT) {
        qDebug() << " dot" << qPrintable(lex.symValue());
        ++dots;
        lex.getSym();
    } else if (lex.symType() == TIE) {
        qDebug() << " tie" << qPrintable(lex.symValue());
        if (lex.symValue() == "^ts") {
            if (inTie) {
                errorHandler("tie start ('^ts') unexpected");
            }
        } else {
            if (!inTie) {
                errorHandler("tie end ('^te') unexpected");
            } else {
                tieStop = true;
                inTie = false;
                lex.getSym();
            }
        }
    } else if (lex.symType() == TRIPLET) {
        qDebug() << " triplet" << qPrintable(lex.symValue());
        if (lex.symValue() == "^3s") {
            if (inTriplet) {
                errorHandler("triplet start ('^3s') unexpected");
            }
        } else {
            if (!inTriplet) {
                errorHandler("triplet end ('^3e') unexpected");
            } else {
                tripletStop = true;
            }
        }
        lex.getSym();
    }

    StartStop triplet = ST_NONE;
    if (inTriplet) {
        if (tripletStart) {
            triplet = ST_START;
        } else if (tripletStop) {
            triplet = ST_STOP;
        } else {
            triplet = ST_CONTINUE;
        }
    }
    qDebug() << " tie start" << tieStart << " tie stop" << tieStop;
    qDebug() << " triplet start" << tripletStart << " triplet stop" << tripletStop;
    NoteDescription noteDesc(caps[1], caps[2], caps[3], dots, tieStart, tieStop, triplet);

    if (measures.isEmpty()) {
        errorHandler("cannot append note: no measure");
    } else {
        measures.last().notes.append(noteDesc);
    }
    tieStart = false;
    tripletStart = false;
    if (tripletStop) {
        inTriplet = false;
        tripletStop = false;
    }
}

/**
   Determine beam for grace note \a index in a group of \a size grace notes.
   */

static QString graceBeam(const int size, const int index)
{
    if (size <= 1) {
        return " ";                           // no beam
    }
    if (index < 0) {
        return " ";                           // no beam (but should not happen)
    }
    if (index == 0) {
        return "b";                           // begin
    } else if (index == (size - 1)) {
        return "e";                           // end
    } else if (index >= size) {
        return " ";                           // no beam (but should not happen)
    } else {
        return "c";                           // continue
    }
}

/**
   Parse a bww embellishment.
   */

void Parser::parseGraces()
{
    qDebug() << "Parser::parseGraces() value:" << qPrintable(lex.symValue());

    const QString c_type = "32";
    const int dots = 0;
    QStringList graces = lex.symValue().split(" ");
    for (int i = 0; i < graces.size(); ++i) {
        const QString beam = graceBeam(graces.size(), i);
        NoteDescription noteDesc(graces.at(i), beam, c_type, dots, false, false, ST_NONE, true);
        if (measures.isEmpty()) {
            errorHandler("cannot append note: no measure");
        } else {
            measures.last().notes.append(noteDesc);
        }
    }
    lex.getSym();
}

/**
   Parse a bww part symbol.
   */

void Parser::parsePart(Bww::MeasureBeginFlags& mbf, Bww::MeasureEndFlags& mef)
{
    qDebug() << "Parser::parsePart() value:" << qPrintable(lex.symValue());
    if (lex.symValue() == "I!''") {
        mbf.repeatBegin = true;
    } else if (lex.symValue() == "'1") {
        mbf.endingFirst = true;
    } else if (lex.symValue() == "'2") {
        mbf.endingSecond = true;
    } else if (lex.symValue() == "''!I") {
        mef.repeatEnd = true;
    } else if (lex.symValue() == "_'") {
        mef.endingEnd = true;
    } else {
        // other silently ignored
    }
    lex.getSym();
}

/**
   Parse a sequence of non-notes.
   */

void Parser::parseSeqNonNotes()
{
    qDebug() << "Parser::parseSeqNonNotes() value:" << qPrintable(lex.symValue());
    MeasureBeginFlags mbfl;
    MeasureEndFlags mefl;
    while (isNonNote(lex.symType()))
    {
        if (lex.symType() == CLEF) {
            mbfl.firstOfSystem = true;
            mefl.lastOfSystem = true;
            lex.getSym();
        } else if (lex.symType() == KEY) {
            lex.getSym(); // ignore
        } else if (lex.symType() == TSIG) {
            parseTSig();
        } else if (lex.symType() == PART) {
            parsePart(mbfl, mefl);
        } else if (lex.symType() == BAR) {
            parseBar(mefl);
        }
    }
    // First end the previous measure
    if (!measures.isEmpty()) {
        measures.last().mef = mefl;
    }
    // Then start a new measure, if necessary
    if (isNote(lex.symType())) {
        MeasureDescription md;
        md.mbf = mbfl;
        measures.append(md);
    }
}

/**
   Parse a sequence of notes.
   Includes handling ties and triplets, but without extensive error checking.
   May break on invalid input.
   */

void Parser::parseSeqNotes()
{
    qDebug() << "Parser::parseSeqNotes() value:" << qPrintable(lex.symValue());
    while (lex.symType() == GRACE || lex.symType() == NOTE || lex.symType() == TIE || lex.symType() == TRIPLET)
    {
        if (lex.symType() == GRACE) {
            parseGraces();
        } else if (lex.symType() == NOTE) {
            parseNote();
        } else if (lex.symType() == TIE) {
            if (lex.symValue() == "^ts") {
                if (inTie) {
                    errorHandler("tie start ('^ts') unexpected");
                } else {
                    tieStart = true;
                }
            } else {
                errorHandler("tie end ('^te') unexpected");
            }
            lex.getSym();
        } else if (lex.symType() == TRIPLET) {
            if (lex.symValue() == "^3s") {
                if (inTriplet) {
                    errorHandler("triplet start ('^3s') unexpected");
                } else {
                    tripletStart = true;
                }
            } else {
                errorHandler("triplet end ('^3e') unexpected");
            }
            lex.getSym();
        }
    }
}

/**
   Parse a bww string. Extract text and type.
   Example: "Air",(Y,C,0,0,Times New Roman,14,400,0,0,18,0,0,0)
   */

void Parser::parseString()
{
    qDebug() << "Parser::parseString() value:" << qPrintable(lex.symValue());

    QRegExp rString("\\\"(.*)\\\",\\(([A-Z]),.*\\)");

    if (rString.exactMatch(lex.symValue())) {
        QStringList caps = rString.capturedTexts();
        if (caps.size() == 3) {
            if (caps.at(2) == "T") {
                title = caps.at(1);
            }
            if (caps.at(2) == "Y") {
                type = caps.at(1);
            }
            if (caps.at(2) == "M") {
                composer = caps.at(1);
            }
            if (caps.at(2) == "F") {
                footer = caps.at(1);
            }
        }
    }
    lex.getSym();
}

/**
   Parse a bww tempo symbol.
   */

void Parser::parseTempo()
{
    qDebug() << "Parser::parseTempo() value:" << qPrintable(lex.symValue());

    QRegExp rTempo("^TuneTempo,(\\d+)");

    if (rTempo.exactMatch(lex.symValue())) {
        QStringList caps = rTempo.capturedTexts();
        if (caps.size() == 2) {
            tempo = caps.at(1).toInt();
        }
    }
    lex.getSym();
}

/**
   Parse a bww tsig symbol.
   */

void Parser::parseTSig()
{
    qDebug() << "Parser::parseTSig() value:" << qPrintable(lex.symValue());

    QRegExp rTSig("(\\d+)_(1|2|4|8|16|32)");

    if (rTSig.exactMatch(lex.symValue())) {
        QStringList caps = rTSig.capturedTexts();
        if (caps.size() == 3) {
            beats = caps.at(1).toInt();
            beat  = caps.at(2).toInt();
            tsigFound = true;
            wrt.tsig(beats, beat);
        }
    }
    lex.getSym();
}
} // namespace Bww