/****************************************************************************
** $Id:  qt/qdragobject.cpp   3.0.3   edited Mar 7 11:36 $
**
** Implementation of Drag and Drop support
**
** Copyright (C) 1992-2000 Trolltech AS.  All rights reserved.
**
** This file is part of the kernel module of the Qt GUI Toolkit.
**
** This file may be distributed under the terms of the Q Public License
** as defined by Trolltech AS of Norway and appearing in the file
** LICENSE.QPL included in the packaging of this file.
**
** This file may be distributed and/or modified under the terms of the
** GNU General Public License version 2 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file.
**
** Licensees holding valid Qt Enterprise Edition or Qt Professional Edition
** licenses may use this file in accordance with the Qt Commercial License
** Agreement provided with the Software.
**
** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
**
** See http://www.trolltech.com/pricing.html or email sales@trolltech.com for
**   information about Qt Commercial License Agreements.
** See http://www.trolltech.com/qpl/ for QPL licensing information.
** See http://www.trolltech.com/gpl/ for GPL licensing information.
**
** Contact info@trolltech.com if any conditions of this licensing are
** not clear to you.
**
**********************************************************************/

#include "qtextcodec.h"

#ifndef QT_NO_MIME

#include "qdragobject.h"
#include "qapplication.h"
#include "qpoint.h"
#include "qwidget.h"
#include "qbuffer.h"
#include "qgif.h"
#include "qregexp.h"
#include <ctype.h>


// both a struct for storing stuff in and a wrapper to avoid polluting
// the name space

class QDragObjectData
{
public:
    QDragObjectData(): hot(0,0) {}
    QPixmap pixmap;
    QPoint hot;
};

static QWidget* last_target;

/*!
  After the drag completes, this function will return the QWidget
  which received the drop, or 0 if the data was dropped on another
  application.

  This can be useful for detecting the case where drag and drop is to
  and from the same widget.
*/
QWidget * QDragObject::target()
{
    return last_target;
}

/*!
  \internal
  Sets the target.
*/
void QDragObject::setTarget(QWidget* t)
{
    last_target = t;
}

class QStoredDragData
{
public:
    QStoredDragData() {}
    const char* fmt;
    QByteArray enc;
};


// These pixmaps approximate the images in the Windows User Interface Guidelines.

// XPM

static const char * const move_xpm[] = {
"11 20 3 1",
".	c None",
#if defined(Q_WS_WIN)
"a	c #000000",
"X	c #FFFFFF", // Windows cursor is traditionally white
#else
"a	c #FFFFFF",
"X	c #000000", // X11 cursor is traditionally black
#endif
"aa.........",
"aXa........",
"aXXa.......",
"aXXXa......",
"aXXXXa.....",
"aXXXXXa....",
"aXXXXXXa...",
"aXXXXXXXa..",
"aXXXXXXXXa.",
"aXXXXXXXXXa",
"aXXXXXXaaaa",
"aXXXaXXa...",
"aXXaaXXa...",
"aXa..aXXa..",
"aa...aXXa..",
"a.....aXXa.",
"......aXXa.",
".......aXXa",
".......aXXa",
"........aa."};

/* XPM */
static const char * const copy_xpm[] = {
"24 30 3 1",
".	c None",
"a	c #000000",
"X	c #FFFFFF",
#if defined(Q_WS_WIN) // Windows cursor is traditionally white
"aa......................",
"aXa.....................",
"aXXa....................",
"aXXXa...................",
"aXXXXa..................",
"aXXXXXa.................",
"aXXXXXXa................",
"aXXXXXXXa...............",
"aXXXXXXXXa..............",
"aXXXXXXXXXa.............",
"aXXXXXXaaaa.............",
"aXXXaXXa................",
"aXXaaXXa................",
"aXa..aXXa...............",
"aa...aXXa...............",
"a.....aXXa..............",
"......aXXa..............",
".......aXXa.............",
".......aXXa.............",
"........aa...aaaaaaaaaaa",
#else
"XX......................",
"XaX.....................",
"XaaX....................",
"XaaaX...................",
"XaaaaX..................",
"XaaaaaX.................",
"XaaaaaaX................",
"XaaaaaaaX...............",
"XaaaaaaaaX..............",
"XaaaaaaaaaX.............",
"XaaaaaaXXXX.............",
"XaaaXaaX................",
"XaaXXaaX................",
"XaX..XaaX...............",
"XX...XaaX...............",
"X.....XaaX..............",
"......XaaX..............",
".......XaaX.............",
".......XaaX.............",
"........XX...aaaaaaaaaaa",
#endif
".............aXXXXXXXXXa",
".............aXXXXXXXXXa",
".............aXXXXaXXXXa",
".............aXXXXaXXXXa",
".............aXXaaaaaXXa",
".............aXXXXaXXXXa",
".............aXXXXaXXXXa",
".............aXXXXXXXXXa",
".............aXXXXXXXXXa",
".............aaaaaaaaaaa"};

/* XPM */
static const char * const link_xpm[] = {
"24 30 3 1",
".	c None",
"a	c #000000",
"X	c #FFFFFF",
#if defined(Q_WS_WIN) // Windows cursor is traditionally white
"aa......................",
"aXa.....................",
"aXXa....................",
"aXXXa...................",
"aXXXXa..................",
"aXXXXXa.................",
"aXXXXXXa................",
"aXXXXXXXa...............",
"aXXXXXXXXa..............",
"aXXXXXXXXXa.............",
"aXXXXXXaaaa.............",
"aXXXaXXa................",
"aXXaaXXa................",
"aXa..aXXa...............",
"aa...aXXa...............",
"a.....aXXa..............",
"......aXXa..............",
".......aXXa.............",
".......aXXa.............",
"........aa...aaaaaaaaaaa",
#else
"XX......................",
"XaX.....................",
"XaaX....................",
"XaaaX...................",
"XaaaaX..................",
"XaaaaaX.................",
"XaaaaaaX................",
"XaaaaaaaX...............",
"XaaaaaaaaX..............",
"XaaaaaaaaaX.............",
"XaaaaaaXXXX.............",
"XaaaXaaX................",
"XaaXXaaX................",
"XaX..XaaX...............",
"XX...XaaX...............",
"X.....XaaX..............",
"......XaaX..............",
".......XaaX.............",
".......XaaX.............",
"........XX...aaaaaaaaaaa",
#endif
".............aXXXXXXXXXa",
".............aXXXaaaaXXa",
".............aXXXXaaaXXa",
".............aXXXaaaaXXa",
".............aXXaaaXaXXa",
".............aXXaaXXXXXa",
".............aXXaXXXXXXa",
".............aXXXaXXXXXa",
".............aXXXXXXXXXa",
".............aaaaaaaaaaa"};

#ifndef QT_NO_DRAGANDDROP

// the universe's only drag manager
static QDragManager * manager = 0;


QDragManager::QDragManager()
    : QObject( qApp, "global drag manager" )
{
    n_cursor = 3;
    pm_cursor = new QPixmap[n_cursor];
    pm_cursor[0] = QPixmap((const char **)move_xpm);
    pm_cursor[1] = QPixmap((const char **)copy_xpm);
    pm_cursor[2] = QPixmap((const char **)link_xpm);
    object = 0;
    dragSource = 0;
    dropWidget = 0;
    if ( !manager )
	manager = this;
    beingCancelled = FALSE;
    restoreCursor = FALSE;
    willDrop = FALSE;
}


QDragManager::~QDragManager()
{
#ifndef QT_NO_CURSOR
    if ( restoreCursor )
	QApplication::restoreOverrideCursor();
#endif
    manager = 0;
    delete [] pm_cursor;
}

#endif


/*!
    Constructs a drag object called \a name, which is a child of \a
    dragSource.

  Note that the drag object will be deleted when \a dragSource is deleted.
*/

QDragObject::QDragObject( QWidget * dragSource, const char * name )
    : QObject( dragSource, name )
{
    d = new QDragObjectData();
#ifndef QT_NO_DRAGANDDROP
    if ( !manager && qApp )
	(void)new QDragManager();
#endif
}


/*! Destroys the drag object, canceling any drag and drop operation
  in which it is involved, and frees up the storage used. */

QDragObject::~QDragObject()
{
#ifndef QT_NO_DRAGANDDROP
    if ( manager && manager->object == this )
	manager->cancel( FALSE );
#endif
    delete d;
}

#ifndef QT_NO_DRAGANDDROP
/*!
  Set the pixmap \a pm to display while dragging the object.
  The platform-specific implementation will use this where it can - so provide
  a small masked pixmap, and do not assume that the user will actually see it.
  For example, cursors on Windows 95 are of limited size.

  The \a hotspot is the point on (or off) the pixmap that should be under the
  cursor as it is dragged. It is relative to the top-left pixel of the pixmap.
*/
void QDragObject::setPixmap(QPixmap pm, const QPoint& hotspot)
{
    d->pixmap = pm;
    d->hot = hotspot;
    if ( manager && manager->object == this )
	manager->updatePixmap();
}

/*!
  \overload
  Uses a hotspot that positions the pixmap below and to the
  right of the mouse pointer.  This allows the user to clearly
  see the point on the window which they are dragging the data onto.
*/
void QDragObject::setPixmap(QPixmap pm)
{
    setPixmap(pm,QPoint(pm.width()/2,pm.height()/2));
}

/*!
  Returns the currently set pixmap
  (which \link QPixmap::isNull() isNull()\endlink if none is set).
*/
QPixmap QDragObject::pixmap() const
{
    return d->pixmap;
}

/*!
  Returns the currently set pixmap hotspot.
*/
QPoint QDragObject::pixmapHotSpot() const
{
    return d->hot;
}

/*!
  Starts a drag operation using the contents of this object,
  using DragDefault mode.

  The function returns TRUE if the caller should delete the
  original copy of the dragged data (but see target()).

  If the drag contains \e references to information
  (eg. file names in a QUriDrag are references)
  then the return value should always be ignored, as the target
  is expected to manipulate the referred-to content directly.
  On X11 the return value should always be correct anyway, but
  on Windows this is not necessarily the case (eg. the file manager
  starts a background process to move files, so the source
  <em>must not</em> delete the files!)
*/
bool QDragObject::drag()
{
    return drag( DragDefault );
}


/*!
  Starts a drag operation using the contents of this object,
  using \c DragMove mode. Be sure to read the constraints described in drag().

  \sa drag() dragCopy() dragLink()
*/
bool QDragObject::dragMove()
{
    return drag( DragMove );
}


/*!
  Starts a drag operation using the contents of this object,
  using \c DragCopy mode. Be sure to read the constraints described in drag().

  \sa drag() dragMove() dragLink()
*/
void QDragObject::dragCopy()
{
    (void)drag( DragCopy );
}

/*!
  Starts a drag operation using the contents of this object,
  using \c DragLink mode. Be sure to read the constraints described in drag().

  \sa drag() dragCopy() dragMove()
*/
void QDragObject::dragLink()
{
    (void)drag( DragLink );
}


/*! \enum QDragObject::DragMode

  This enum describes the possible drag modes.

   \value DragDefault  The mode is determined heuristically.
   \value DragCopy  The data is copied, never moved.
   \value DragMove  The data is moved, if dragged at all.
   \value DragLink  The data is linked, if dragged at all.
   \value DragCopyOrMove  The user chooses the mode
	    by using a control key to switch from the default.
*/


/*!
    \overload
  Starts a drag operation using the contents of this object.

  At this point, the object becomes owned by Qt, not the
  application.  You should not delete the drag object nor
  anything it references.  The actual transfer of data to
  the target application will be done during future event
  processing - after that time the drag object will be deleted.

  Returns TRUE if the dragged data was dragged as a \e move,
  indicating that the caller should remove the original source
  of the data (the drag object must continue to have a copy).

    The \a mode specifies the drag mode (see \l{QDragObject::DragMode}.)
  Normally one of the simpler drag(), dragMove(), or dragCopy() functions
  would be used instead.

  \warning in Qt 1.x, drag operations all return FALSE.
*/
bool QDragObject::drag( DragMode mode )
{ // ### In Qt 1.x?  huh?
    if ( manager )
	return manager->drag( this, mode );
    else
	return FALSE;
}

#endif


/*!  Returns a pointer to the drag source where this object originated.
*/

QWidget * QDragObject::source()
{
    if ( parent() && parent()->isWidgetType() )
	return (QWidget *)parent();
    else
	return 0;
}


/*! \class QDragObject qdragobject.h

  \brief The QDragObject class encapsulates MIME-based data transfer.

  \ingroup draganddrop

  QDragObject is the base class for all data that needs to be transferred
  between and within applications, both for drag and drop and for the
  clipboard.

  See the \link dnd.html Drag-and-drop documentation\endlink for
  an overview of how to provide drag and drop in your application.

  See the QClipboard documentation for
  an overview of how to provide cut-and-paste in your application.

  The drag() function is used to start a drag operation. You can specify the
  \l DragMode in the call or use one of the convenience functions dragCopy(),
  dragMove() or dragLink(). The drag source where the data originated is
  retrieved with source(). If the data was dropped on a widget within the
  application target() will return a pointer to that widget. Specify the
  pixmap to display during the drag with setPixmap().
*/

static
void stripws(QCString& s)
{
    int f;
    while ( (f=s.find(' ')) >= 0 )
	s.remove(f,1);
}

static
const char * staticCharset(int i)
{
    static QCString localcharset;

    switch ( i ) {
      case 0:
	return "UTF-8";
      case 1:
	return "ISO-10646-UCS-2";
      case 2:
	return ""; // in the 3rd place - some Xdnd targets might only look at 3
      case 3:
	if ( localcharset.isNull() ) {
	    QTextCodec *localCodec = QTextCodec::codecForLocale();
	    if ( localCodec ) {
		localcharset = localCodec->name();
		localcharset = localcharset.lower();
		stripws(localcharset);
	    } else {
		localcharset = "";
	    }
	}
	return localcharset;
    }
    return 0;
}


class QTextDragPrivate {
public:
    QTextDragPrivate();
    
    enum { nfmt=4 };

    QString txt;
    QCString fmt[nfmt];
    QCString subtype;

    void setSubType(const QCString & st)
    {
	subtype = st.lower();
	for ( int i=0; i<nfmt; i++ ) {
	    fmt[i] = "text/";
	    fmt[i].append(subtype);
	    QCString cs = staticCharset(i);
	    if ( !cs.isEmpty() ) {
		fmt[i].append(";charset=");
		fmt[i].append(cs);
	    }
	}
    }
};

inline QTextDragPrivate::QTextDragPrivate()
{
    setSubType("plain");
}

/*!  Sets the MIME subtype of the text being dragged to \a st. The default subtype
  is "plain", so the default MIME type of the text is "text/plain".  You
  might use this to declare that the text is "text/html" by calling
  setSubtype("html").
*/
void QTextDrag::setSubtype( const QCString & st)
{
    d->setSubType(st);
}

/*! \class QTextDrag qdragobject.h

  \brief The QTextDrag class is a drag and drop object for
	      transferring plain and Unicode text.

  \ingroup draganddrop

  Plain text is passed in a QString which may contain multiple lines
  (i.e. may contain newline characters).

  Qt provides no built-in mechanism for delivering only single-line.

  For more information about drag and drop, see the QDragObject class
  and the \link dnd.html drag and drop documentation\endlink.
*/


/*!  Constructs a text drag object and sets it to \a text.  \a dragSource
  must be the drag source; \a name is the object name.
*/

QTextDrag::QTextDrag( const QString &text,
		      QWidget * dragSource, const char * name )
    : QDragObject( dragSource, name )
{
    d = new QTextDragPrivate;
    setText( text );
}


/*!  Constructs a default text drag object.  \a dragSource must be the drag
  source; \a name is the object name.
*/

QTextDrag::QTextDrag( QWidget * dragSource, const char * name )
    : QDragObject( dragSource, name )
{
    d = new QTextDragPrivate;
}


/*!  Destroys the text drag object and frees up all allocated resources.
*/
QTextDrag::~QTextDrag()
{
    delete d;
}


/*!
  Sets the text to be dragged to \a text.  You will need to call this
  if you did not pass the text during construction.
*/
void QTextDrag::setText( const QString &text )
{
    d->txt = text;
}


/*!
  \reimp
*/
const char * QTextDrag::format(int i) const
{
    if ( i >= d->nfmt )
	return 0;
    return d->fmt[i];
}

static
QTextCodec* findcharset(const QCString& mimetype)
{
    int i=mimetype.find("charset=");
    if ( i >= 0 ) {
	QCString cs = mimetype.mid(i+8);
	stripws(cs);
	i = cs.find(';');
	if ( i >= 0 )
	    cs = cs.left(i);
	// May return 0 if unknown charset
	return QTextCodec::codecForName(cs,cs.length()*3/4);
    }
    // no charset=, use locale
    return QTextCodec::codecForLocale();
}

static
QTextCodec* findcodec(const QMimeSource* e)
{
    QTextCodec* r;
    const char* f;
    int i;
    for ( i=0; (f=e->format(i)); i++ )
	if ( (r = findcharset(QCString(f).lower())) )
	    return r;
    return 0;
}


/*!
  \reimp
*/
QByteArray QTextDrag::encodedData(const char* mime) const
{
    QCString r;
    if ( 0==qstrnicmp(mime,"text/",5) ) {
	QCString m(mime);
	m = m.lower();
	QTextCodec *codec = findcharset(m);
	if ( !codec )
	    return r;
	QString text( d->txt );
#if defined(Q_WS_WIN)
	int index = text.find( QString::fromLatin1("\r\n"), 0 );
	while ( index != -1 ) {
	    text.replace( index, 2, QChar('\n') );
	    index = text.find( "\r\n", index );
	}
#endif
	r = codec->fromUnicode(text);
	if (!codec || codec->mibEnum() != 1000) {
	    // Don't include NUL in size (QCString::resize() adds NUL)
#if defined(Q_WS_WIN)
	    // This is needed to ensure the \0 isn't lost on Windows 95
	    if ( qWinVersion() & Qt::WV_DOS_based )
		((QByteArray&)r).resize(r.length()+1);
	    else
#endif
		((QByteArray&)r).resize(r.length());
	}
    }
    return r;
}

/*!
  Returns TRUE if the information in \a e can be decoded into a
  QString; otherwise returns FALSE.
  \sa decode()
*/
bool QTextDrag::canDecode( const QMimeSource* e )
{
    const char* f;
    for (int i=0; (f=e->format(i)); i++) {
	if ( 0==qstrnicmp(f,"text/",5) ) {
	    return findcodec(e) != 0;
	}
    }
    return 0;
}

/*!
  \overload

  Attempts to decode the dropped information in \a e into \a str.
  Returns TRUE if successful; otherwise returns FALSE.  If \a subtype
  is null, any text subtype is accepted; otherwise only the specified
  \a subtype is accepted.

  \sa canDecode()
*/
bool QTextDrag::decode( const QMimeSource* e, QString& str, QCString& subtype )
{
    if(!e)
	return FALSE;

    if ( e->cacheType == QMimeSource::Text ) {
	str = *e->cache.txt.str;
	subtype = *e->cache.txt.subtype;
	return TRUE;
    }

    const char* mime;
    for (int i=0; (mime = e->format(i)); i++) {
	if ( 0==qstrnicmp(mime,"text/",5) ) {
	    QCString m(mime);
	    m = m.lower();
	    int semi = m.find(';');
	    if ( semi < 0 )
		semi = m.length();
	    QCString foundst = m.mid(5,semi-5);
	    if ( subtype.isNull() || foundst == subtype ) {
		QTextCodec* codec = findcharset(m);
		if ( codec ) {
		    QByteArray payload;

		    payload = e->encodedData(mime);
		    if ( payload.size() ) {
			int l;
			if ( codec->mibEnum() != 1000) {
			    // length is at NUL or payload.size()
			    l = 0;
			    while ( l < (int)payload.size() && payload[l] )
				l++;
			} else {
			    l = payload.size();
			}

			str = codec->toUnicode(payload,l);

			if ( subtype.isNull() )
			    subtype = foundst;

			QMimeSource *m = (QMimeSource*)e;
			m->clearCache();
			m->cacheType = QMimeSource::Text;
			m->cache.txt.str = new QString( str );
			m->cache.txt.subtype = new QCString( subtype );

			return TRUE;
		    }
		}
	    }
	}
    }
    return FALSE;
}

/*!
  Attempts to decode the dropped information in \a e
  into \a str. Returns TRUE if successful; otherwise returns FALSE.

  \sa canDecode()
*/
bool QTextDrag::decode( const QMimeSource* e, QString& str )
{
    QCString st;
    return decode(e,str,st);
}


/*
  QImageDrag could use an internal MIME type for communicating QPixmaps
  and QImages rather than always converting to raw data.  This is available
  for that purpose and others.  It is not currently used.
*/
class QImageDragData
{
public:
};


/*! \class QImageDrag qdragobject.h

  \brief The QImageDrag class provides a drag and drop object for
  transferring images.

  \ingroup draganddrop

  Images are offered to the receiving application in multiple formats,
  determined by the \link QImage::outputFormats() output formats\endlink
  in Qt.

  For more information about drag and drop, see the QDragObject class
  and the \link dnd.html drag and drop documentation\endlink.
*/

/*!  Constructs an image drag object and sets it to \a image.  \a dragSource
  must be the drag source; \a name is the object name. */

QImageDrag::QImageDrag( QImage image,
			QWidget * dragSource, const char * name )
    : QDragObject( dragSource, name ),
	d(0)
{
    setImage( image );
}

/*!  Constructs a default text drag object.  \a dragSource must be the drag
  source; \a name is the object name.
*/

QImageDrag::QImageDrag( QWidget * dragSource, const char * name )
    : QDragObject( dragSource, name ),
	d(0)
{
}


/*!  Destroys the image drag object and frees up all allocated resources.
*/

QImageDrag::~QImageDrag()
{
    // nothing
}


/*!
  Sets the image to be dragged to \a image.  You will need to call this if you did
  not pass the image during construction.
*/
void QImageDrag::setImage( QImage image )
{
    img = image; // ### detach?
    ofmts = QImage::outputFormats();
    ofmts.remove("PBM"); // remove non-raw PPM
    if ( image.depth()!=32 ) {
	// BMP better than PPM for paletted images
	if ( ofmts.remove("BMP") ) // move to front
	    ofmts.insert(0,"BMP");
    }
    // PNG is best of all
    if ( ofmts.remove("PNG") ) // move to front
	ofmts.insert(0,"PNG");

    if(cacheType == QMimeSource::NoCache) { //cache it
	cacheType = QMimeSource::Graphics;
	cache.gfx.img = new QImage( img );
	cache.gfx.pix = 0;
    }
}

/*!
  \reimp
*/
const char * QImageDrag::format(int i) const
{
    if ( i < (int)ofmts.count() ) {
	static QCString str;
	str.sprintf("image/%s",(((QImageDrag*)this)->ofmts).at(i));
	str = str.lower();
	if ( str == "image/pbmraw" )
	    str = "image/ppm";
	return str;
    } else {
	return 0;
    }
}

/*!
  \reimp
*/
QByteArray QImageDrag::encodedData(const char* fmt) const
{
    if ( qstrnicmp( fmt, "image/", 6 )==0 ) {
	QCString f = fmt+6;
	QByteArray data;
	QBuffer w( data );
	w.open( IO_WriteOnly );
	QImageIO io( &w, f.upper() );
	io.setImage( img );
	if  ( !io.write() )
	    return QByteArray();
	w.close();
	return data;
    } else {
	return QByteArray();
    }
}

/*!
  Returns TRUE if the information in mime source \a e can be decoded
  into an image. \sa decode()
*/
bool QImageDrag::canDecode( const QMimeSource* e ) {
    QStrList fileFormats = QImageIO::inputFormats();

    fileFormats.first();
    while ( fileFormats.current()) {
	QCString format = fileFormats.current();
	QCString type = "image/" + format.lower();
	if ( e->provides(type.data()))
	    return TRUE;
	fileFormats.next();
    }

    return FALSE;
}

/*!
  Attempts to decode the dropped information in mime source \a e
  into \a img. Returns TRUE if successful; otherwise returns FALSE.

  \sa canDecode()
*/
bool QImageDrag::decode( const QMimeSource* e, QImage& img )
{
    if ( !e )
	return FALSE;
    if ( e->cacheType == QMimeSource::Graphics ) {
	img = *e->cache.gfx.img;
	return TRUE;
    }

    QByteArray payload;
    QStrList fileFormats = QImageIO::inputFormats();
    // PNG is best of all
    if ( fileFormats.remove("PNG") ) // move to front
	fileFormats.insert(0,"PNG");
    fileFormats.first();
    while ( fileFormats.current() ) {
	QCString format = fileFormats.current();
	QCString type = "image/" + format.lower();
	payload = e->encodedData( type.data() );
	if ( !payload.isEmpty() )
	    break;
	fileFormats.next();
    }

    if ( payload.isEmpty() )
	return FALSE;

    img.loadFromData(payload);
    if ( img.isNull() )
	return FALSE;
    QMimeSource *m = (QMimeSource*)e;
    m->clearCache();
    m->cacheType = QMimeSource::Graphics;
    m->cache.gfx.img = new QImage( img );
    m->cache.gfx.pix = 0;
    return TRUE;
}

/*!
  \overload

  Attempts to decode the dropped information in mime source \a e into
  pixmap \a pm. Returns TRUE if successful; otherwise returns FALSE.

  This is a convenience function that converts to \a pm via a QImage.

  \sa canDecode()
*/
bool QImageDrag::decode( const QMimeSource* e, QPixmap& pm )
{
    if ( !e )
	return FALSE;

    if ( e->cacheType == QMimeSource::Graphics && e->cache.gfx.pix) {
	pm = *e->cache.gfx.pix;
	return TRUE;
    }

    QImage img;
    // We avoid dither, since the image probably came from this display
    if ( decode( e, img ) ) {
	if ( !pm.convertFromImage( img, AvoidDither ) )
	    return FALSE;
	// decode initialized the cache for us

	QMimeSource *m = (QMimeSource*)e;
	m->cache.gfx.pix = new QPixmap( pm );
	return TRUE;
    }
    return FALSE;
}




/*!
  \class QStoredDrag qdragobject.h
  \ingroup draganddrop
  \brief The QStoredDrag class provides a simple stored-value drag object for arbitrary MIME data.

  When a block of data has only one representation, you can use
  a QStoredDrag to hold it.

  For more information about drag and drop, see the QDragObject
  class and the \link dnd.html drag and drop documentation\endlink.
*/

/*!
  Constructs a QStoredDrag.  The \a dragSource and \a name are passed
  to the QDragObject constructor, and the format is set to \a mimeType.

  The data will be unset.  Use setEncodedData() to set it.
*/
QStoredDrag::QStoredDrag( const char* mimeType, QWidget * dragSource, const char * name ) :
    QDragObject(dragSource,name)
{
    d = new QStoredDragData();
    d->fmt = qstrdup(mimeType);
}

/*!
  Destroys the drag object and frees up all allocated resources.
*/
QStoredDrag::~QStoredDrag()
{
    delete [] (char*)d->fmt;
    delete d;
}

/*!
  \reimp
*/
const char * QStoredDrag::format(int i) const
{
    if ( i==0 )
	return d->fmt;
    else
	return 0;
}


/*!
  Sets the encoded data of this drag object to \a encodedData.  The
  encoded data is what's delivered to the drop sites. It must be in a
  strictly defined and portable format.

  The drag object can't be dropped (by the user) until this function
  has been called.
*/

void QStoredDrag::setEncodedData( const QByteArray & encodedData )
{
    d->enc = encodedData.copy();
}

/*!
  Returns the stored data. \a m contains the data's format.

  \sa setEncodedData()
*/
QByteArray QStoredDrag::encodedData(const char* m) const
{
    if ( !qstricmp(m,d->fmt) )
	return d->enc;
    else
	return QByteArray();
}


/*!
  \class QUriDrag qdragobject.h
  \ingroup draganddrop
  \brief The QUriDrag class provides a drag object for a list of URI references.

  URIs are a useful way to refer to files that may be distributed
  across multiple machines.  A URI will often refer to
  a file on a machine local to both the drag source and the
  drop target, so the URI will be equivalent to passing a
  file name but will be more extensible.

  Use URIs in Unicode form so that the user can comfortably edit and view
  them.  For use in HTTP or other protocols, use the correctly escaped
  ASCII form.

  You can convert a list of file names to file URIs using
  setFileNames(), or into human-readble for with setUnicodeUris().

  Static functions are provided to convert between filenames and URIs,
  e.g. uriToLocalFile() and localFileToUri(), and to and from
  human-readable form, e.g. uriToUnicodeUri(), unicodeUriToUri(). You
  can also decode URIs from a mimesource into a list with
  decodeLocalFiles() and decodeToUnicodeUris().

*/

/*!
  Constructs an object to drag the list of URIs in \a uris.
  The \a dragSource and \a name arguments are passed on to
  QStoredDrag.  Note that URIs are always in escaped UTF8
  encoding, as defined by the W3C.
*/
QUriDrag::QUriDrag( QStrList uris,
	    QWidget * dragSource, const char * name ) :
    QStoredDrag( "text/uri-list", dragSource, name )
{
    setUris(uris);
}

/*!
  Constructs a object to drag.  You will need to call
  setUris() before you start the drag().
  Passes \a dragSource and \a name to the QStoredDrag constructor.
*/
QUriDrag::QUriDrag( QWidget * dragSource, const char * name ) :
    QStoredDrag( "text/uri-list", dragSource, name )
{
}

/*!
  Destroys the object.
*/
QUriDrag::~QUriDrag()
{
}

/*!
  Changes the list of \a uris to be dragged.
*/
void QUriDrag::setUris( QStrList uris )
{
    QByteArray a;
    int c=0;
    for ( const char* s = uris.first(); s; s = uris.next() ) {
	int l = qstrlen(s);
	a.resize(c+l+2);
	memcpy(a.data()+c,s,l);
	memcpy(a.data()+c+l,"\r\n",2);
	c+=l+2;
    }
    setEncodedData(a);
}


/*!
  Returns TRUE if decode() would be able to decode \a e; otherwise
  returns FALSE.
*/
bool QUriDrag::canDecode( const QMimeSource* e )
{
    return e->provides( "text/uri-list" );
}

/*!
  Decodes URIs from \a e, placing the result in \a l (which is first cleared).

  Returns TRUE if the event contained a valid list of URIs; otherwise
  returns FALSE.
*/
bool QUriDrag::decode( const QMimeSource* e, QStrList& l )
{
    QByteArray payload = e->encodedData( "text/uri-list" );
    if ( payload.size() ) {
	l.clear();
	l.setAutoDelete(TRUE);
	uint c=0;
	const char* d = payload.data();
	while (c < payload.size() && d[c]) {
	    uint f = c;
	    // Find line end
	    while (c < payload.size() && d[c] && d[c]!='\r'
		    && d[c] != '\n')
		c++;
	    QCString s(d+f,c-f+1);
	    if ( s[0] != '#' ) // non-comment?
		l.append( s );
	    // Skip junk
	    while (c < payload.size() && d[c] &&
		    (d[c]=='\n' || d[c]=='\r'))
		c++;
	}
	return TRUE;
    }
    return FALSE;
}

static uint htod( int h )
{
    if ( isdigit(h) )
	return h - '0';
    return tolower( h ) - 'a' + 10;
}

/*!
  \fn QUriDrag::setFilenames( const QStringList & )
  \obsolete

  Use setFileNames() instead (notice the N).
*/

/*!
  Sets the URIs to be the local-file URIs equivalent to \a fnames.

  \sa localFileToUri(), setUris()
*/
void QUriDrag::setFileNames( const QStringList & fnames )
{
    QStrList uris;
    for ( QStringList::ConstIterator i = fnames.begin();
	    i != fnames.end(); ++i )
	uris.append( localFileToUri(*i) );
    setUris( uris );
}

/*!
  Sets the URIs to be the Unicode URIs (only useful for displaying to
  humans) \a uuris.

  \sa localFileToUri(), setUris()
*/
void QUriDrag::setUnicodeUris( const QStringList & uuris )
{
    QStrList uris;
    for ( QStringList::ConstIterator i = uuris.begin();
	    i != uuris.end(); ++i )
	uris.append( unicodeUriToUri(*i) );
    setUris( uris );
}

/*!
  Returns the URI equivalent to the Unicode URI (only useful for
  displaying to humans) \a uuri.

  \sa uriToLocalFile()
*/
QCString QUriDrag::unicodeUriToUri(const QString& uuri)
{
    QCString utf8 = uuri.utf8();
    QCString escutf8;
    int n = utf8.length();
    for (int i=0; i<n; i++) {
	if ( utf8[i] >= 'a' && utf8[i] <= 'z'
	  || utf8[i] == '/'
	  || utf8[i] >= '0' && utf8[i] <= '9'
	  || utf8[i] >= 'A' && utf8[i] <= 'Z'

	  || utf8[i] == '-' || utf8[i] == '_'
	  || utf8[i] == '.' || utf8[i] == '!'
	  || utf8[i] == '~' || utf8[i] == '*'
	  || utf8[i] == '(' || utf8[i] == ')'
	  || utf8[i] == '\''

	  // Allow this through, so that all URI-references work.
	  || utf8[i] == '#'

	  || utf8[i] == ';'
	  || utf8[i] == '?' || utf8[i] == ':'
	  || utf8[i] == '@' || utf8[i] == '&'
	  || utf8[i] == '=' || utf8[i] == '+'
	  || utf8[i] == '$' || utf8[i] == ',' )
	{
	    escutf8 += utf8[i];
	} else {
	    // Everything else is escaped as %HH
	    QCString s(4);
	    s.sprintf("%%%02x",(uchar)utf8[i]);
	    escutf8 += s;
	}
    }
    return escutf8;
}

/*!
  Returns the URI equivalent to the absolute
  local file \a filename.

  \sa uriToLocalFile()
*/
QCString QUriDrag::localFileToUri(const QString& filename)
{
    QString r = filename;
#ifdef Q_WS_WIN
    // Slosh -> Slash
    int slosh;
    while ( (slosh=r.find('\\')) >= 0 ) {
	r[slosh] = '/';
    }
    // Drive
    if ( r[0] != '/' ) {
	int colon = r.find(':');
	if ( colon >= 0 ) {
	    r[colon] = '|';
	    if ( r[colon+1] != '/' )
		r.insert(colon+1,'/');
	}
	r.insert(0,'/');
    }
#endif
    return unicodeUriToUri(QString("file://" + r));
}

/*!
  Returns the Unicode URI (only useful for
  displaying to humans) equivalent to \a uri.

  \sa localFileToUri()
*/
QString QUriDrag::uriToUnicodeUri(const char* uri)
{
    QCString utf8;

    while (*uri) {
	switch (*uri) {
	  case '%': {
		uint ch = (uchar) uri[1];
		if ( ch && uri[2] ) {
		    ch = htod( ch ) * 16 + htod( (uchar) uri[2] );
		    utf8 += (char) ch;
		    uri += 2;
		}
	    }
	    break;
	  default:
	    utf8 += *uri;
	}
	++uri;
    }

    return QString::fromUtf8(utf8);
}

/*!
  Returns the name of a local file equivalent to \a uri
  or a null string if \a uri is not a local file.

  \sa localFileToUri()
*/
QString QUriDrag::uriToLocalFile(const char* uri)
{
    QString file;

    if ( uri && 0==qstrnicmp(uri,"file:/",6) ) {
	uri += 6;
	if ( uri[0] != '/' || uri[1] == '/' ) {
	    // It is local.
	    file = uriToUnicodeUri(uri);
	    if ( uri[1] == '/' ) {
		file.remove(0,1);
	    } else {
		file.insert(0,'/');
	    }
#ifdef Q_WS_WIN
	    if ( file.length() > 2 && file[0] == '/' && file[2] == '|' ) {
		file[2] = ':';
		file.remove(0,1);
	    }
	    // Leave slash as slashes.
#endif
	}
    }

    return file;
}

/*!
  Decodes URIs from the mime source event \a e, converts them to local
  files if they refer to local files, and places them in \a l (which
  is first cleared).

  Returns TRUE if \e contained a valid list of URIs; otherwise
  returns FALSE.
  The list will be empty if no URIs were local files.
*/
bool QUriDrag::decodeLocalFiles( const QMimeSource* e, QStringList& l )
{
    QStrList u;
    if ( !decode( e, u ) )
	return FALSE;

    l.clear();
    for (const char* s=u.first(); s; s=u.next()) {
	QString lf = uriToLocalFile(s);
	if ( !lf.isNull() )
	    l.append( lf );
    }
    return TRUE;
}

/*!
  Decodes URIs from the mime source event \a e, converts them to
  Unicode URIs (only useful for displaying to humans), placing them in
  \a l (which is first cleared).

  Returns TRUE if \e contained a valid list of URIs; otherwise returns
  FALSE.
*/
bool QUriDrag::decodeToUnicodeUris( const QMimeSource* e, QStringList& l )
{
    QStrList u;
    if ( !decode( e, u ) )
	return FALSE;

    l.clear();
    for (const char* s=u.first(); s; s=u.next())
	l.append( uriToUnicodeUri(s) );

    return TRUE;
}


#ifndef QT_NO_DRAGANDDROP
/*!
  If the source of the drag operation is a widget in this application,
  this function returns that source, otherwise it returns 0.  The
  source of the operation is the first parameter to to drag object
  subclass.

  This is useful if your widget needs special behavior when dragging
  to itself, etc.

  See QDragObject::QDragObject() and subclasses.
*/
QWidget* QDropEvent::source() const
{
    return manager ? manager->dragSource : 0;
}
#endif

/*! \class QColorDrag qdragobject.h

  \brief The QColorDrag class provides a drag and drop object for
	      transferring colors.

  \ingroup draganddrop

  This class provides a drag object which can be used to transfer data
  about colors for drag and drop and over the clipboard. For example, it
  is used in the QColorDialog.

  The color is set in the constructor but can be changed with
  setColor().

  For more information about drag and drop, see the QDragObject class
  and the \link dnd.html drag and drop documentation\endlink.
*/

/*!
  Constructs a color drag object with the color \a col.
    Passes \a dragsource and \a name to the QStoredDrag constructor.
*/

QColorDrag::QColorDrag( const QColor &col, QWidget *dragsource, const char *name )
    : QStoredDrag( "application/x-color", dragsource, name )
{
    setColor( col );
}

/*!
  Constructs a color drag object with a white color
    Passes \a dragsource and \a name to the QStoredDrag constructor.
*/

QColorDrag::QColorDrag( QWidget *dragsource, const char *name )
    : QStoredDrag( "application/x-color", dragsource, name )
{
    setColor( Qt::white );
}

/*!
  Sets the color of the color drag to \a col.
*/

void QColorDrag::setColor( const QColor &col )
{
    QByteArray data;
    ushort rgba[ 4 ];
    data.resize( sizeof( rgba ) );
    rgba[ 0 ] = col.red()  * 0xFF;
    rgba[ 1 ] = col.green() * 0xFF;
    rgba[ 2 ] = col.blue()  * 0xFF;
    rgba[ 3 ] = 0xFFFF; // Alpha not supported yet.
    memcpy( data.data(), rgba, sizeof( rgba) );
    setEncodedData( data );
}

/*!
  Returns TRUE if the color drag object can decode the
  mime source \a e.
*/

bool QColorDrag::canDecode( QMimeSource *e )
{
    return e->provides( "application/x-color" );
}

/*!
  Decodes the mime source \a e and sets the decoded values to \a col.
*/

bool QColorDrag::decode( QMimeSource *e, QColor &col )
{
    QByteArray data = e->encodedData( "application/x-color" );
    ushort rgba[ 4 ];
    if( data.size() != sizeof( rgba ) )
	return FALSE;
    memcpy( rgba, data.data(), sizeof( rgba ) );
    col.setRgb( rgba[ 0 ] / 0xFF, rgba[ 1 ] / 0xFF, rgba[ 2 ] / 0xFF );
    return TRUE;
}

#endif // QT_NO_MIME
