utility.cpp Example File

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 #include "utility.h"

 #include <QtCore>

 #define QT_GALLERY_MEDIA_ART_ILLEGAL_CHARACTERS \
     "\\(.*\\)|\\{.*\\}|\\[.*\\]|<.*>|[\\(\\)_\\{\\}\\[\\]\\!@#$\\^&\\*\\+\\=\\|\\\\/\"'\\?~`]"

 Utility::Utility(QObject *parent)
     : QObject(parent)
 #if defined(Q_OS_UNIX) && !(defined(Q_OS_SYMBIAN) || defined(Q_OS_MAC))
     , illegalCharacters(QLatin1String(QT_GALLERY_MEDIA_ART_ILLEGAL_CHARACTERS))
     , whitespace(QCryptographicHash::hash(" ", QCryptographicHash::Md5).toHex())
 #endif
 {
 }

 Utility::~Utility()
 {
 }

 QString Utility::formatDuration(int duration) const
 {
     const int seconds = duration % 60;
     const int minutes = (duration /= 60) % 60;
     const int hours = duration / 60;

     QTime time(hours, minutes, seconds);

     return time.hour() > 0
             ? time.toString(tr("h:mm:ss"))
             : time.toString(tr("mm:ss"));
 }

 #if defined(Q_OS_UNIX) && !(defined(Q_OS_SYMBIAN) || defined(Q_OS_MAC))
 QUrl Utility::getAlbumArtUrl(const QString &artist, const QString &title) const
 {
     QString fileName = QDir::homePath()
             + QLatin1String("/.cache/media-art/album-")
             + hash(artist)
             + QLatin1Char('-')
             + hash(title)
             + QLatin1String(".jpeg");

     if (QFile::exists(fileName))
         return QUrl::fromLocalFile(fileName);

     return QUrl();

 }

 QUrl Utility::getAlbumArtThumbnailUrl(const QString &artist, const QString &title) const
 {
     QUrl albumUrl = getAlbumArtUrl(artist, title);

     if (albumUrl.isValid()) {
 #if defined(Q_WS_MAEMO_5)
         QString thumbnailPath = QDir::homePath()
                 + QLatin1String("/.thumbnails/cropped/")
                 + QCryptographicHash::hash(
                         albumUrl.toString().toUtf8(), QCryptographicHash::Md5).toHex()
                 + QLatin1String(".jpeg");
 #elif defined(Q_WS_MAEMO_6)
         QString thumbnailPath = QDir::homePath()
                 + QLatin1String("/.thumbnails/grid/")
                 + QCryptographicHash::hash(
                         albumUrl.toString().toUtf8(), QCryptographicHash::Md5).toHex()
                 + QLatin1String(".jpeg");
 #else
         QString thumbnailPath = QDir::homePath()
                 + QLatin1String("/.thumbnails/normal/")
                 + QCryptographicHash::hash(
                         albumUrl.toEncoded(), QCryptographicHash::Md5).toHex()
                 + QLatin1String(".png");
 #endif
         if (QFile::exists(thumbnailPath))
             return QUrl::fromLocalFile(thumbnailPath);
     }
     return albumUrl;
 }

 QString Utility::hash(const QString &identifier) const
 {
     if (identifier.isEmpty()) {
         return whitespace;
     } else {
         return QCryptographicHash::hash(
                 identifier.toLower().remove(illegalCharacters).simplified().toUtf8(),
                 QCryptographicHash::Md5).toHex();
     }
 }

 #else

 QUrl Utility::getAlbumArtUrl(const QString &, const QString &) const
 {
     return QUrl();
 }

 QUrl Utility::getAlbumArtThumbnailUrl(const QString &, const QString &) const
 {
     return QUrl();
 }

 #endif