src/gui/image/qpicture.cpp

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/****************************************************************************
**
** Copyright (C) 1992-2006 Trolltech ASA. All rights reserved.
**
** This file is part of the QtGui module of the Qt Toolkit.
**
** This file may be used under the terms of the GNU General Public
** License version 2.0 as published by the Free Software Foundation
** and appearing in the file LICENSE.GPL included in the packaging of
** this file.  Please review the following information to ensure GNU
** General Public Licensing requirements will be met:
** http://www.trolltech.com/products/qt/opensource.html
**
** If you are unsure which license is appropriate for your use, please
** review the following information:
** http://www.trolltech.com/products/qt/licensing.html or contact the
** sales department at sales@trolltech.com.
**
** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
**
****************************************************************************/

#include "qpicture.h"
#include <private/qpicture_p.h>

#ifndef QT_NO_PICTURE

#include <private/qfactoryloader_p.h>
#include <private/qpaintengine_pic_p.h>

#include "qdatastream.h"
#include "qfile.h"
#include "qimage.h"
#include "qmutex.h"
#include "qpainter.h"
#include "qpainterpath.h"
#include "qpixmap.h"
#include "qregion.h"
#include "qdebug.h"

void qt_format_text(const QFont &fnt, const QRectF &_r,
                    int tf, const QString& str, QRectF *brect,
                    int tabstops, int *, int tabarraylen,
                    QPainter *painter);

const char  *qt_mfhdr_tag = "QPIC"; // header tag
static const quint16 mfhdr_maj = 8; // major version #
static const quint16 mfhdr_min = 0; // minor version #
extern int qt_defaultDpi();

QPicture::QPicture(int formatVersion)
    : QPaintDevice(),
      d_ptr(new QPicturePrivate)
{
    Q_D(QPicture);
    d_ptr->q_ptr = this;
    d->paintEngine = 0;

    if (formatVersion == 0)
        qWarning("QPicture: invalid format version 0");

    // still accept the 0 default from before Qt 3.0.
    if (formatVersion > 0 && formatVersion != (int)mfhdr_maj) {
        d->formatMajor = formatVersion;
        d->formatMinor = 0;
        d->formatOk = false;
    }
    else {
        d->resetFormat();
    }
}

QPicture::QPicture(const QPicture &pic)
    : QPaintDevice(), d_ptr(pic.d_ptr)
{
    d_func()->ref.ref();
}

QPicture::QPicture(QPicturePrivate &dptr)
    : QPaintDevice(),
      d_ptr(&dptr)
{
    d_ptr->q_ptr = this;
}

QPicture::~QPicture()
{
    if (!d_func()->ref.deref()) {
        delete d_func()->paintEngine;
        delete d_func();
    }
}

int QPicture::devType() const
{
    return QInternal::Picture;
}

bool QPicture::isNull() const
{
    return d_func()->pictb.buffer().isNull();
}

uint QPicture::size() const
{
    return d_func()->pictb.buffer().size();
}

const char* QPicture::data() const
{
    return d_func()->pictb.buffer();
}

void QPicture::detach()
{
    if (d_func()->ref != 1)
        detach_helper();
}

bool QPicture::isDetached() const
{
    return d_func()->ref == 1;
}

void QPicture::setData(const char* data, uint size)
{
    detach();
    d_func()->pictb.setData(data, size);
    d_func()->resetFormat();                                // we'll have to check
}


bool QPicture::load(const QString &fileName, const char *format)
{
    QFile f(fileName);
    if (!f.open(QIODevice::ReadOnly))
        return false;
    return load(&f, format);
}

bool QPicture::load(QIODevice *dev, const char *format)
{
    if(format) {
#ifndef QT_NO_PICTUREIO
        QPictureIO io(dev, format);
        bool result = io.read();
        if (result) {
            operator=(io.picture());

        } else if (format)
#else
            bool result = false;
#endif
        {
            qWarning("QPicture::load: No such picture format: %s", format);
        }
        return result;
    }

    detach();
    QByteArray a = dev->readAll();

    d_func()->pictb.setData(a);                        // set byte array in buffer
    return d_func()->checkFormat();
}

bool QPicture::save(const QString &fileName, const char *format)
{
    if (paintingActive()) {
        qWarning("QPicture::save: still being painted on. "
                  "Call QPainter::end() first");
        return false;
    }


    if(format) {
#ifndef QT_NO_PICTUREIO
        QPictureIO io(fileName, format);
        bool result = io.write();
        if (result) {
            operator=(io.picture());
        } else if (format)
#else
        bool result = false;
#endif
        {
            qWarning("QPicture::save: No such picture format: %s", format);
        }
        return result;
    }

    QFile f(fileName);
    if (!f.open(QIODevice::WriteOnly))
        return false;
    return save(&f, format);
}

bool QPicture::save(QIODevice *dev, const char *format)
{
    if (paintingActive()) {
        qWarning("QPicture::save: still being painted on. "
                  "Call QPainter::end() first");
        return false;
    }

    if(format) {
#ifndef QT_NO_PICTUREIO
        QPictureIO io(dev, format);
        bool result = io.write();
        if (result) {
            operator=(io.picture());
        } else if (format)
#else
        bool result = false;
#endif
        {
            qWarning("QPicture::save: No such picture format: %s", format);
        }
        return result;
    }

    dev->write(d_func()->pictb.buffer(), d_func()->pictb.buffer().size());
    return true;
}

QRect QPicture::boundingRect() const
{
    Q_D(const QPicture);
    // Use override rect where possible.
    if (!d->override_rect.isEmpty())
        return d->override_rect;

    if (!d->formatOk)
        d_ptr->checkFormat();

    return d->brect;
}

void QPicture::setBoundingRect(const QRect &r)
{
    d_func()->override_rect = r;
}

bool QPicture::play(QPainter *painter)
{
    Q_D(QPicture);

    if (d->pictb.size() == 0)                        // nothing recorded
        return true;

    if (!d->formatOk && !d->checkFormat())
        return false;

    d->pictb.open(QIODevice::ReadOnly);                // open buffer device
    QDataStream s;
    s.setDevice(&d->pictb);                        // attach data stream to buffer
    s.device()->seek(10);                        // go directly to the data
    s.setVersion(d->formatMajor == 4 ? 3 : d->formatMajor);

    quint8  c, clen;
    quint32 nrecords;
    s >> c >> clen;
    Q_ASSERT(c == QPicturePrivate::PdcBegin);
    // bounding rect was introduced in ver 4. Read in checkFormat().
    if (d->formatMajor >= 4) {
        qint32 dummy;
        s >> dummy >> dummy >> dummy >> dummy;
    }
    s >> nrecords;
    if (!exec(painter, s, nrecords)) {
        qWarning("QPicture::play: Format error");
        d->pictb.close();
        return false;
    }
    d->pictb.close();
    return true;                                // no end-command
}


bool QPicture::exec(QPainter *painter, QDataStream &s, int nrecords)
{
    Q_D(QPicture);
#if defined(QT_DEBUG)
    int                strm_pos;
#endif
    quint8     c;                      // command id
    quint8     tiny_len;               // 8-bit length descriptor
    qint32     len;                    // 32-bit length descriptor
    qint16     i_16, i1_16, i2_16;     // parameters...
    qint8      i_8;
    quint32    ul;
    QByteArray  str1;
    QString     str;
    QPointF     p, p1, p2;
    QRectF      r;
    QPolygonF   a;
    QPolygon    pa;
    QColor      color;
    QFont       font;
    QPen        pen;
    QBrush      brush;
    QRegion     rgn;
    QMatrix     matrix;

    QMatrix worldMatrix = painter->matrix();
    worldMatrix.scale(qreal(painter->device()->logicalDpiX()) / qreal(qt_defaultDpi()),
                      qreal(painter->device()->logicalDpiY()) / qreal(qt_defaultDpi()));
    painter->setMatrix(worldMatrix);

    while (nrecords-- && !s.atEnd()) {
        s >> c;                 // read cmd
        s >> tiny_len;          // read param length
        if (tiny_len == 255)    // longer than 254 bytes
            s >> len;
        else
            len = tiny_len;
#if defined(QT_DEBUG)
        strm_pos = s.device()->pos();
#endif
        switch (c) {            // exec cmd
        case QPicturePrivate::PdcNOP:
            break;
        case QPicturePrivate::PdcDrawPoint:
            s >> p;
            painter->drawPoint(p);
            break;
        case QPicturePrivate::PdcDrawPoints:
// ## implement me in the picture paint engine
//                 s >> a >> i1_32 >> i2_32;
//                 painter->drawPoints(a.mid(i1_32, i2_32));
            break;
        case QPicturePrivate::PdcDrawPath: {
            QPainterPath path;
            s >> path;
            painter->drawPath(path);
            break;
        }
        case QPicturePrivate::PdcDrawLine:
            s >> p1 >> p2;
            painter->drawLine(p1, p2);
            break;
        case QPicturePrivate::PdcDrawRect:
            s >> r;
            painter->drawRect(r);
            break;
        case QPicturePrivate::PdcDrawRoundRect:
            s >> r >> i1_16 >> i2_16;
            painter->drawRoundRect(r, i1_16, i2_16);
            break;
        case QPicturePrivate::PdcDrawEllipse:
            s >> r;
            painter->drawEllipse(r);
            break;
        case QPicturePrivate::PdcDrawArc:
            s >> r >> i1_16 >> i2_16;
            painter->drawArc(r, i1_16, i2_16);
            break;
        case QPicturePrivate::PdcDrawPie:
            s >> r >> i1_16 >> i2_16;
            painter->drawPie(r, i1_16, i2_16);
            break;
        case QPicturePrivate::PdcDrawChord:
            s >> r >> i1_16 >> i2_16;
            painter->drawChord(r, i1_16, i2_16);
            break;
        case QPicturePrivate::PdcDrawLineSegments:
            s >> pa;
            painter->drawLines(pa);
            pa.clear();
            break;
        case QPicturePrivate::PdcDrawPolyline:
            s >> a;
            painter->drawPolyline(a);
            a.clear();
            break;
        case QPicturePrivate::PdcDrawPolygon:
            s >> a >> i_8;
            painter->drawPolygon(a, i_8 ? Qt::WindingFill : Qt::OddEvenFill);
            a.clear();
            break;
        case QPicturePrivate::PdcDrawCubicBezier: {
            s >> a;
            QPainterPath path;
            Q_ASSERT(a.size() == 4);
            path.moveTo(a.at(0));
            path.cubicTo(a.at(1), a.at(2), a.at(3));
            painter->strokePath(path, painter->pen());
            a.clear();
        }
            break;
        case QPicturePrivate::PdcDrawText:
            s >> p >> str1;
            painter->drawText(p, str1);
            break;
        case QPicturePrivate::PdcDrawTextFormatted:
            s >> r >> i_16 >> str1;
            painter->drawText(r, i_16, str1);
            break;
        case QPicturePrivate::PdcDrawText2:
            s >> p >> str;
            painter->drawText(p, str);
            break;
        case QPicturePrivate::PdcDrawText2Formatted:
            s >> r >> i_16 >> str;
            painter->drawText(r, i_16, str);
            break;
        case QPicturePrivate::PdcDrawTextItem: {
            Qt::LayoutDirection oldDir = painter->layoutDirection();

            s >> p >> str >> font >> ul;

            if (ul & QTextItem::RightToLeft)
                painter->setLayoutDirection(Qt::RightToLeft);
            else
                painter->setLayoutDirection(Qt::LeftToRight);

            qt_format_text(font, QRectF(p, QSizeF(1, 1)), Qt::TextSingleLine | Qt::TextDontClip, str, /*brect=*/0, /*tabstops=*/0, /*...*/0, /*tabarraylen=*/0, painter);

            painter->setLayoutDirection(oldDir);
            break;
        }
        case QPicturePrivate::PdcDrawPixmap: {
            QPixmap pixmap;
            if (d->formatMajor < 4) {
                s >> p >> pixmap;
                painter->drawPixmap(p, pixmap);
            } else {
                QRectF sr;
                s >> r >> pixmap >> sr;
                painter->drawPixmap(r, pixmap, sr);
            }
        }
            break;
        case QPicturePrivate::PdcDrawTiledPixmap: {
            QPixmap pixmap;
            s >> r >> pixmap >> p;
            painter->drawTiledPixmap(r, pixmap, p);
        }
            break;
        case QPicturePrivate::PdcDrawImage: {
            QImage image;
            if (d->formatMajor < 4) {
                s >> p >> image;
                painter->drawPixmap(p, QPixmap::fromImage(image));
            } else {
                s >> r >> image;
                painter->drawPixmap(r, QPixmap::fromImage(image), QRectF(0, 0, r.width(), r.height()));
            }
        }
            break;
        case QPicturePrivate::PdcBegin:
            s >> ul;                        // number of records
            if (!exec(painter, s, ul))
                return false;
            break;
        case QPicturePrivate::PdcEnd:
            if (nrecords == 0)
                return true;
            break;
        case QPicturePrivate::PdcSave:
            painter->save();
            break;
        case QPicturePrivate::PdcRestore:
            painter->restore();
            break;
        case QPicturePrivate::PdcSetBkColor:
            s >> color;
            painter->setBackground(color);
            break;
        case QPicturePrivate::PdcSetBkMode:
            s >> i_8;
            painter->setBackgroundMode((Qt::BGMode)i_8);
            break;
        case QPicturePrivate::PdcSetROP: // NOP
            break;
        case QPicturePrivate::PdcSetBrushOrigin:
            s >> p;
            painter->setBrushOrigin(p);
            break;
        case QPicturePrivate::PdcSetFont:
            s >> font;
            painter->setFont(font);
            break;
        case QPicturePrivate::PdcSetPen:
            s >> pen;
            painter->setPen(pen);
            break;
        case QPicturePrivate::PdcSetBrush:
            s >> brush;
            painter->setBrush(brush);
            break;
// #ifdef Q_Q3PAINTER
//         case QPicturePrivate::PdcSetTabStops:
//                 s >> i_16;
//                 painter->setTabStops(i_16);
//                 break;
//             case QPicturePrivate::PdcSetTabArray:
//                 s >> i_16;
//                 if (i_16 == 0) {
//                     painter->setTabArray(0);
//                 } else {
//                     int *ta = new int[i_16];
//                     for (int i=0; i<i_16; i++) {
//                         s >> i1_16;
//                         ta[i] = i1_16;
//                     }
//                     painter->setTabArray(ta);
//                     delete [] ta;
//                 }
//                 break;
// #endif
        case QPicturePrivate::PdcSetVXform:
            s >> i_8;
            painter->setViewTransformEnabled(i_8);
            break;
        case QPicturePrivate::PdcSetWindow:
            s >> r;
            painter->setWindow(r.toRect());
            break;
        case QPicturePrivate::PdcSetViewport:
            s >> r;
            painter->setViewport(r.toRect());
            break;
        case QPicturePrivate::PdcSetWXform:
            s >> i_8;
            painter->setMatrixEnabled(i_8);
            break;
        case QPicturePrivate::PdcSetWMatrix:
            s >> matrix >> i_8;
            // i_8 is always false due to updateXForm() in qpaintengine_pic.cpp
            painter->setMatrix(matrix * worldMatrix, false);
            break;
// #ifdef Q_Q3PAINTER
//             case QPicturePrivate::PdcSaveWMatrix:
//                 painter->saveWorldMatrix();
//                 break;
//             case QPicturePrivate::PdcRestoreWMatrix:
//                 painter->restoreWorldMatrix();
//                 break;
// #endif
        case QPicturePrivate::PdcSetClip:
            s >> i_8;
            painter->setClipping(i_8);
            break;
        case QPicturePrivate::PdcSetClipRegion:
            s >> rgn >> i_8;
            painter->setClipRegion(rgn);
            break;
        case QPicturePrivate::PdcSetClipPath:
            {
                QPainterPath path;
                s >> path >> i_8;
                painter->setClipPath(path, Qt::ClipOperation(i_8));
                break;
            }
        case QPicturePrivate::PdcSetRenderHint:
            s >> ul;
            painter->setRenderHint(QPainter::Antialiasing,
                                   bool(ul & QPainter::Antialiasing));
            painter->setRenderHint(QPainter::SmoothPixmapTransform,
                                   bool(ul & QPainter::SmoothPixmapTransform));
            break;
        default:
            qWarning("QPicture::play: Invalid command %d", c);
            if (len)                        // skip unknown command
                s.device()->seek(s.device()->pos()+len);
        }
#if defined(QT_DEBUG)
        //qDebug("device->at(): %i, strm_pos: %i len: %i", s.device()->at(), strm_pos, len);
        Q_ASSERT(qint32(s.device()->pos() - strm_pos) == len);
#endif
    }
    return false;
}

int QPicture::metric(PaintDeviceMetric m) const
{
    int val;
    QRect brect = boundingRect();
    switch (m) {
        case PdmWidth:
            val = brect.width();
            break;
        case PdmHeight:
            val = brect.height();
            break;
        case PdmWidthMM:
            val = int(25.4/qt_defaultDpi()*brect.width());
            break;
        case PdmHeightMM:
            val = int(25.4/qt_defaultDpi()*brect.height());
            break;
        case PdmDpiX:
        case PdmPhysicalDpiX:
            val = qt_defaultDpi();
            break;
        case PdmDpiY:
        case PdmPhysicalDpiY:
            val = qt_defaultDpi();
            break;
        case PdmNumColors:
            val = 16777216;
            break;
        case PdmDepth:
            val = 24;
            break;
        default:
            val = 0;
            qWarning("QPicture::metric: Invalid metric command");
    }
    return val;
}

void QPicture::detach_helper()
{
    Q_D(QPicture);
    QPicturePrivate *x = new QPicturePrivate;
    int pictsize = size();
    x->pictb.setData(data(), pictsize);
    if (d->pictb.isOpen()) {
        x->pictb.open(d->pictb.openMode());
        x->pictb.seek(d->pictb.pos());
    }
    x->trecs = d->trecs;
    x->formatOk = d->formatOk;
    x->formatMinor = d->formatMinor;
    x->brect = d->brect;
    x->override_rect = d->override_rect;
    x = qAtomicSetPtr(&d_ptr, x);
    if (!x->ref.deref())
        delete x;
}

QPicture& QPicture::operator=(const QPicture &p)
{
    qAtomicAssign<QPicturePrivate>(d_ptr, p.d_ptr);
    return *this;
}

void QPicturePrivate::resetFormat()
{
    formatOk = false;
    formatMajor = mfhdr_maj;
    formatMinor = mfhdr_min;
}


bool QPicturePrivate::checkFormat()
{
    resetFormat();

    // can't check anything in an empty buffer
    if (pictb.size() == 0 || pictb.isOpen())
        return false;

    pictb.open(QIODevice::ReadOnly);                        // open buffer device
    QDataStream s;
    s.setDevice(&pictb);                        // attach data stream to buffer

    char mf_id[4];                                // picture header tag
    s.readRawData(mf_id, 4);                        // read actual tag
    if (memcmp(mf_id, qt_mfhdr_tag, 4) != 0) {         // wrong header id
        qWarning("QPicturePaintEngine::checkFormat: Incorrect header");
        pictb.close();
        return false;
    }

    int cs_start = sizeof(quint32);                // pos of checksum word
    int data_start = cs_start + sizeof(quint16);
    quint16 cs,ccs;
    QByteArray buf = pictb.buffer();        // pointer to data

    s >> cs;                                // read checksum
    ccs = (quint16) qChecksum(buf.constData() + data_start, buf.size() - data_start);
    if (ccs != cs) {
        qWarning("QPicturePaintEngine::checkFormat: Invalid checksum %x, %x expected",
                  ccs, cs);
        pictb.close();
        return false;
    }

    quint16 major, minor;
    s >> major >> minor;                        // read version number
    if (major > mfhdr_maj) {                // new, incompatible version
        qWarning("QPicturePaintEngine::checkFormat: Incompatible version %d.%d",
                  major, minor);
        pictb.close();
        return false;
    }
    s.setVersion(major != 4 ? major : 3);

    quint8  c, clen;
    s >> c >> clen;
    if (c == QPicturePrivate::PdcBegin) {
        if (!(major >= 1 && major <= 3)) {
            qint32 l, t, w, h;
            s >> l >> t >> w >> h;
            brect = QRect(l, t, w, h);
        }
    } else {
        qWarning("QPicturePaintEngine::checkFormat: Format error");
        pictb.close();
        return false;
    }
    pictb.close();

    formatOk = true;                        // picture seems to be ok
    formatMajor = major;
    formatMinor = minor;
    return true;
}

QPaintEngine *QPicture::paintEngine() const
{
    if (!d_func()->paintEngine)
        const_cast<QPicture*>(this)->d_func()->paintEngine = new QPicturePaintEngine;
    return d_func()->paintEngine;
}

/*****************************************************************************
  QPicture stream functions
 *****************************************************************************/

QDataStream &operator<<(QDataStream &s, const QPicture &r)
{
    quint32 size = r.d_func()->pictb.buffer().size();
    s << size;
    // null picture ?
    if (size == 0)
        return s;
    // just write the whole buffer to the stream
    s.writeRawData (r.d_func()->pictb.buffer(), r.d_func()->pictb.buffer().size());
    return s;
}

QDataStream &operator>>(QDataStream &s, QPicture &r)
{
    QDataStream sr;

    // "init"; this code is similar to the beginning of QPicture::cmd()
    sr.setDevice(&r.d_func()->pictb);
    sr.setVersion(r.d_func()->formatMajor);
    quint32 len;
    s >> len;
    QByteArray data;
    if (len > 0) {
        data.resize(len);
        s.readRawData(data.data(), len);
    }

    r.d_func()->pictb.setData(data);
    r.d_func()->resetFormat();
    return s;
}


#ifndef QT_NO_PICTUREIO
#include "qregexp.h"
#include "qapplication.h"
#include "qpictureformatplugin.h"

const char* QPicture::pictureFormat(const QString &fileName)
{
    return QPictureIO::pictureFormat(fileName);
}

QList<QByteArray> QPicture::inputFormats()
{
    return QPictureIO::inputFormats();
}

static QStringList qToStringList(const QList<QByteArray> arr)
{
    QStringList list;
    for (int i = 0; i < arr.count(); ++i)
        list.append(QString::fromLatin1(arr.at(i)));
    return list;
}

QStringList QPicture::inputFormatList()
{
    return qToStringList(QPictureIO::inputFormats());
}


QStringList QPicture::outputFormatList()
{
    return qToStringList(QPictureIO::outputFormats());
}

QList<QByteArray> QPicture::outputFormats()
{
    return QPictureIO::outputFormats();
}

/*****************************************************************************
  QPictureIO member functions
 *****************************************************************************/

struct QPictureIOData
{
    QPicture        pi;                                // picture
    int                iostat;                                // IO status
    QByteArray        frmt;                                // picture format
    QIODevice  *iodev;                                // IO device
    QString        fname;                                // file name
    QString     descr;                                // picture description
    const char *parameters;
    int quality;
    float gamma;
};

QPictureIO::QPictureIO()
{
    init();
}

QPictureIO::QPictureIO(QIODevice *ioDevice, const char *format)
{
    init();
    d->iodev = ioDevice;
    d->frmt = format;
}

QPictureIO::QPictureIO(const QString &fileName, const char* format)
{
    init();
    d->frmt = format;
    d->fname = fileName;
}

void QPictureIO::init()
{
    d = new QPictureIOData();
    d->parameters = 0;
    d->quality = -1; // default quality of the current format
    d->gamma=0.0f;
    d->iostat = 0;
    d->iodev  = 0;
}

QPictureIO::~QPictureIO()
{
    if (d->parameters)
        delete [] (char*)d->parameters;
    delete d;
}


/*****************************************************************************
  QPictureIO picture handler functions
 *****************************************************************************/

class QPictureHandler
{
public:
    QPictureHandler(const char *f, const char *h, const QByteArray& fl,
                     picture_io_handler r, picture_io_handler w);
    QByteArray              format;                        // picture format
    QRegExp              header;                        // picture header pattern
    enum TMode { Untranslated=0, TranslateIn, TranslateInOut } text_mode;
    picture_io_handler  read_picture;                // picture read function
    picture_io_handler  write_picture;                // picture write function
    bool              obsolete;                        // support not "published"
};

QPictureHandler::QPictureHandler(const char *f, const char *h, const QByteArray& fl,
                              picture_io_handler r, picture_io_handler w)
    : format(f), header(QString::fromLatin1(h))
{
    text_mode = Untranslated;
    if (fl.contains('t'))
        text_mode = TranslateIn;
    else if (fl.contains('T'))
        text_mode = TranslateInOut;
    obsolete = fl.contains('O');
    read_picture  = r;
    write_picture = w;
}

typedef QList<QPictureHandler *> QPHList;
static QPHList pictureHandlers;

#ifndef QT_NO_LIBRARY
Q_GLOBAL_STATIC(QMutex, mutex)
Q_GLOBAL_STATIC_WITH_ARGS(QFactoryLoader, loader,
                          (QPictureFormatInterface_iid,
                           QCoreApplication::libraryPaths(),
                           QLatin1String("/pictureformats")))
#endif
void qt_init_picture_plugins()
{
#ifndef QT_NO_LIBRARY
    QMutexLocker locker(mutex());
    QFactoryLoader *loader = ::loader();
    QStringList keys = loader->keys();
    for (int i = 0; i < keys.count(); ++i)
        if (QPictureFormatInterface *format = qobject_cast<QPictureFormatInterface*>(loader->instance(keys.at(i))))
            format->installIOHandler(keys.at(i));
#endif
}

static void cleanup()
{
    // make sure that picture handlers are delete before plugin manager
    while (!pictureHandlers.isEmpty())
        delete pictureHandlers.takeFirst();
}

void qt_init_picture_handlers()                // initialize picture handlers
{
    static bool done = false;
    if (done) return;
    done = true;

    qAddPostRoutine(cleanup);
}

static QPictureHandler *get_picture_handler(const char *format)
{                                                // get pointer to handler
    qt_init_picture_handlers();
    qt_init_picture_plugins();
    for (int i = 0; i < pictureHandlers.size(); ++i) {
        if (pictureHandlers.at(i)->format == format)
            return pictureHandlers.at(i);
    }
    return 0;                                        // no such handler
}


void QPictureIO::defineIOHandler(const char *format,
                                const char *header,
                                const char *flags,
                                picture_io_handler readPicture,
                                picture_io_handler writePicture)
{
    qt_init_picture_handlers();
    QPictureHandler *p;
    p = new QPictureHandler(format, header, QByteArray(flags), readPicture, writePicture);
    pictureHandlers.prepend(p);
}


/*****************************************************************************
  QPictureIO normal member functions
 *****************************************************************************/

const QPicture &QPictureIO::picture() const { return d->pi; }

int QPictureIO::status() const { return d->iostat; }

const char *QPictureIO::format() const { return d->frmt; }

QIODevice *QPictureIO::ioDevice() const { return d->iodev; }

QString QPictureIO::fileName() const { return d->fname; }


QString QPictureIO::description() const { return d->descr; }

void QPictureIO::setPicture(const QPicture &picture)
{
    d->pi = picture;
}

void QPictureIO::setStatus(int status)
{
    d->iostat = status;
}

void QPictureIO::setFormat(const char *format)
{
    d->frmt = format;
}

void QPictureIO::setIODevice(QIODevice *ioDevice)
{
    d->iodev = ioDevice;
}

void QPictureIO::setFileName(const QString &fileName)
{
    d->fname = fileName;
}

int QPictureIO::quality() const
{
    return d->quality;
}

void QPictureIO::setQuality(int q)
{
    d->quality = q;
}

const char *QPictureIO::parameters() const
{
    return d->parameters;
}

void QPictureIO::setParameters(const char *parameters)
{
    if (d->parameters)
        delete [] (char*)d->parameters;
    d->parameters = qstrdup(parameters);
}

void QPictureIO::setGamma(float gamma)
{
    d->gamma=gamma;
}

float QPictureIO::gamma() const
{
    return d->gamma;
}

void QPictureIO::setDescription(const QString &description)
{
    d->descr = description;
}


QByteArray QPictureIO::pictureFormat(const QString &fileName)
{
    QFile file(fileName);
    QByteArray format;
    if (!file.open(QIODevice::ReadOnly))
        return format;
    format = pictureFormat(&file);
    file.close();
    return format;
}

QByteArray QPictureIO::pictureFormat(QIODevice *d)
{
    // if you change this change the documentation for defineIOHandler()
    const int buflen = 14;

    char buf[buflen];
    char buf2[buflen];
    qt_init_picture_handlers();
    qt_init_picture_plugins();
    int pos = d->pos();                      // save position
    int rdlen = d->read(buf, buflen);        // read a few bytes

    QByteArray format;
    if (rdlen != buflen)
        return format;

    memcpy(buf2, buf, buflen);

    for (int n = 0; n < rdlen; n++)
        if (buf[n] == '\0')
            buf[n] = '\001';
    if (rdlen > 0) {
        buf[rdlen - 1] = '\0';
        QString bufStr = QString::fromLatin1(buf);
        for (int i = 0; i < pictureHandlers.size(); ++i) {
            if (pictureHandlers.at(i)->header.indexIn(bufStr) != -1) { // try match with headers
                format = pictureHandlers.at(i)->format;
                break;
            }
        }
    }
    d->seek(pos);                                // restore position
    return format;
}

QList<QByteArray> QPictureIO::inputFormats()
{
    QList<QByteArray> result;

    qt_init_picture_handlers();
    qt_init_picture_plugins();

    for (int i = 0; i < pictureHandlers.size(); ++i) {
        QPictureHandler *p = pictureHandlers.at(i);
        if (p->read_picture && !p->obsolete  && !result.contains(p->format))
            result.append(p->format);
    }
    qSort(result);

    return result;
}

QList<QByteArray> QPictureIO::outputFormats()
{
    qt_init_picture_handlers();
    qt_init_picture_plugins();

    QList<QByteArray> result;
    for (int i = 0; i < pictureHandlers.size(); ++i) {
        QPictureHandler *p = pictureHandlers.at(i);
        if (p->write_picture && !p->obsolete && !result.contains(p->format))
            result.append(p->format);
    }
    return result;
}



bool QPictureIO::read()
{
    QFile           file;
    const char          *picture_format;
    QPictureHandler *h;

    if (d->iodev) {                                // read from io device
        // ok, already open
    } else if (!d->fname.isEmpty()) {                // read from file
        file.setFileName(d->fname);
        if (!file.open(QIODevice::ReadOnly))
            return false;                        // cannot open file
        d->iodev = &file;
    } else {                                        // no file name or io device
        return false;
    }
    if (d->frmt.isEmpty()) {
        // Try to guess format
        picture_format = pictureFormat(d->iodev);        // get picture format
        if (!picture_format) {
            if (file.isOpen()) {                        // unknown format
                file.close();
                d->iodev = 0;
            }
            return false;
        }
    } else {
        picture_format = d->frmt;
    }

    h = get_picture_handler(picture_format);
    if (file.isOpen()) {
#if !defined(Q_OS_UNIX)
        if (h && h->text_mode) {                // reopen in translated mode
            file.close();
            file.open(QIODevice::ReadOnly | QIODevice::Text);
        }
        else
#endif
            file.seek(0);                        // position to start
    }
    d->iostat = 1;                                        // assume error

    if (h && h->read_picture)
        (*h->read_picture)(this);

    if (file.isOpen()) {                        // picture was read using file
        file.close();
        d->iodev = 0;
    }
    return d->iostat == 0;                                // picture successfully read?
}


bool QPictureIO::write()
{
    if (d->frmt.isEmpty())
        return false;
    QPictureHandler *h = get_picture_handler(d->frmt);
    if (!h || !h->write_picture) {
        qWarning("QPictureIO::write: No such picture format handler: %s",
                 format());
        return false;
    }
    QFile file;
    if (!d->iodev && !d->fname.isEmpty()) {
        file.setFileName(d->fname);
        bool translate = h->text_mode==QPictureHandler::TranslateInOut;
        QIODevice::OpenMode fmode = translate ? QIODevice::WriteOnly | QIODevice::Text : QIODevice::OpenMode(QIODevice::WriteOnly);
        if (!file.open(fmode))                // couldn't create file
            return false;
        d->iodev = &file;
    }
    d->iostat = 1;
    (*h->write_picture)(this);
    if (file.isOpen()) {                        // picture was written using file
        file.close();
        d->iodev = 0;
    }
    return d->iostat == 0;                                // picture successfully written?
}
#endif //QT_NO_PICTUREIO

#endif // QT_NO_PICTURE

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