imagethumbs.cpp

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#include "imagethumbs.h"
 
#include <QDir>
#include <QStringList>
 
#include "libmythbase/mythcorecontext.h"  // for MYTH_APPNAME_MYTHPREVIEWGEN
#include "libmythbase/mythdirs.h"         // for GetAppBinDir
#include "libmythbase/mythlogging.h"
#include "libmythbase/mythsystemlegacy.h"
#include "libmythui/mythimage.h"
 
#include "imagemetadata.h"
 
template <class DBFS>
ThumbThread<DBFS>::~ThumbThread()
{
    cancel();
    wait();
}
 
 
template <class DBFS>
void ThumbThread<DBFS>::cancel()
{
    // Clear all queues
    QMutexLocker locker(&m_mutex);
    m_requestQ.clear();
    m_backgroundQ.clear();
}
 
 
template <class DBFS>
void ThumbThread<DBFS>::Enqueue(const TaskPtr &task)
{
    if (task)
    {
        bool background = task->m_priority > kBackgroundPriority;
 
        QMutexLocker locker(&m_mutex);
        if (background)
            m_backgroundQ.insert(task->m_priority, task);
        else
            m_requestQ.insert(task->m_priority, task);
 
        // restart if not already running
        if ((m_doBackground || !background) && !this->isRunning())
            this->start();
    }
}
 
 
template <class DBFS>
void ThumbThread<DBFS>::AbortDevice(int devId, const QString &action)
{
    if (action == "DEVICE CLOSE ALL" || action == "DEVICE CLEAR ALL")
    {
        if (isRunning())
            LOG(VB_FILE, LOG_INFO,
                QString("Aborting all thumbnails %1").arg(action));
 
        // Abort thumbnail generation for all devices
        cancel();
        return;
    }
 
    LOG(VB_FILE, LOG_INFO, QString("Aborting thumbnails (%1) for '%2'")
        .arg(action).arg(m_dbfs.DeviceName(devId)));
 
    // Remove all tasks for specific device from every queue
    QMutexLocker locker(&m_mutex);
    RemoveTasks(m_requestQ, devId);
    RemoveTasks(m_backgroundQ, devId);
    if (isRunning())
        // Wait until current task is complete - it may be using the device
        m_taskDone.wait(&m_mutex, 3000);
}
 
 
#if QT_VERSION < QT_VERSION_CHECK(6,0,0)
#define QMutableMultiMapIterator QMutableMapIterator
#endif
 
template <class DBFS>
void ThumbThread<DBFS>::RemoveTasks(ThumbQueue &queue, int devId)
{
    QMutableMultiMapIterator<int, TaskPtr> it(queue);
    while (it.hasNext())
    {
        it.next();
        TaskPtr task = it.value();
        // All thumbs in a task come from same device
        if (task && !task->m_images.isEmpty()
                && task->m_images.at(0)->m_device == devId)
            it.remove();
    }
}
 
 
template <class DBFS>
void ThumbThread<DBFS>::run()
{
    RunProlog();
 
    setPriority(QThread::LowestPriority);
 
    while (true)
    {
        // Signal previous task is complete (its files have been closed)
        m_taskDone.wakeAll();
 
        // Do all we can to run in background
        QThread::yieldCurrentThread();
 
        // process next highest-priority task
        TaskPtr task;
        {
            QMutexLocker locker(&m_mutex);
            if (!m_requestQ.isEmpty())
                task = m_requestQ.take(m_requestQ.constBegin().key());
            else if (m_doBackground && !m_backgroundQ.isEmpty())
                task = m_backgroundQ.take(m_backgroundQ.constBegin().key());
            else
                // quit when both queues exhausted
                break;
        }
 
        // Shouldn't receive empty requests
        if (task->m_images.isEmpty())
            continue;
 
        if (task->m_action == "CREATE")
        {
            ImagePtrK im = task->m_images.at(0);
 
            QString err = CreateThumbnail(im, task->m_priority);
 
            if (!err.isEmpty())
            {
                LOG(VB_GENERAL, LOG_ERR,  QString("%1").arg(err));
            }
            else if (task->m_notify)
            {
                // notify clients when done
                m_dbfs.Notify("THUMB_AVAILABLE",
                              QStringList(QString::number(im->m_id)));
            }
        }
        else if (task->m_action == "DELETE")
        {
            for (const auto& im : std::as_const(task->m_images))
            {
                QString thumbnail = im->m_thumbPath;
                if (!QDir::root().remove(thumbnail))
                {
                    LOG(VB_FILE, LOG_WARNING,
                        QString("Failed to delete thumbnail %1").arg(thumbnail));
                    continue;
                }
                LOG(VB_FILE, LOG_DEBUG,
                    QString("Deleted thumbnail %1").arg(thumbnail));
 
                // Clean up empty dirs
                QString path = QFileInfo(thumbnail).path();
                if (QDir::root().rmpath(path))
                    LOG(VB_FILE, LOG_DEBUG,
                        QString("Cleaned up path %1").arg(path));
            }
        }
        else if (task->m_action == "MOVE")
        {
            for (const auto& im : std::as_const(task->m_images))
            {
                // Build new thumb path
                QString newThumbPath =
                        m_dbfs.GetAbsThumbPath(m_dbfs.ThumbDir(im->m_device),
                                               m_dbfs.ThumbPath(*im.data()));
 
                // Ensure path exists
                if (QDir::root().mkpath(QFileInfo(newThumbPath).path())
                        && QFile::rename(im->m_thumbPath, newThumbPath))
                {
                    LOG(VB_FILE, LOG_DEBUG, QString("Moved thumbnail %1 -> %2")
                        .arg(im->m_thumbPath, newThumbPath));
                }
                else
                {
                    LOG(VB_FILE, LOG_WARNING,
                        QString("Failed to rename thumbnail %1 -> %2")
                        .arg(im->m_thumbPath, newThumbPath));
                    continue;
                }
 
                // Clean up empty dirs
                QString path = QFileInfo(im->m_thumbPath).path();
                if (QDir::root().rmpath(path))
                    LOG(VB_FILE, LOG_DEBUG,
                        QString("Cleaned up path %1").arg(path));
            }
        }
        else
        {
            LOG(VB_GENERAL, LOG_ERR,
                QString("Unknown task %1").arg(task->m_action));
        }
    }
 
    RunEpilog();
}
 
 
template <class DBFS>
QString ThumbThread<DBFS>::CreateThumbnail(const ImagePtrK &im, int thumbPriority)
{
    if (QDir::root().exists(im->m_thumbPath))
    {
        LOG(VB_FILE, LOG_DEBUG,  QString("[%3] %2 already exists")
            .arg(im->m_thumbPath).arg(thumbPriority));
        return {}; // Notify anyway
    }
 
    // Local filenames are always absolute
    // Remote filenames are absolute from the scanner only
    // UI requests (derived from Db) are relative
    QString imagePath = m_dbfs.GetAbsFilePath(im);
    if (imagePath.isEmpty())
        return QString("Empty image path: %1").arg(im->m_filePath);
 
    // Ensure path exists
    QDir::root().mkpath(QFileInfo(im->m_thumbPath).path());
 
    QImage image;
    if (im->m_type == kImageFile)
    {
        if (!image.load(imagePath))
            return QString("Failed to open image %1").arg(imagePath);
 
        // Resize to optimise load/display time by FE's
        image = image.scaled(QSize(240,180), Qt::KeepAspectRatio, Qt::SmoothTransformation);
    }
    else if (im->m_type == kVideoFile)
    {
        // Run Preview Generator in foreground
        QString cmd = GetAppBinDir() + MYTH_APPNAME_MYTHPREVIEWGEN;
        QStringList args;
        args << "--size 320x240"; // Video thumbnails are also shown in slideshow
        args << QString("--infile '%1'").arg(imagePath);
        args << QString("--outfile '%1'").arg(im->m_thumbPath);
 
        MythSystemLegacy ms(cmd, args,
                            kMSRunShell           |
                            kMSDontBlockInputDevs |
                            kMSDontDisableDrawing |
                            kMSProcessEvents      |
                            kMSAutoCleanup        |
                            kMSPropagateLogs);
        ms.SetNice(10);
        ms.SetIOPrio(7);
        ms.Run(30s);
        if (ms.Wait() != GENERIC_EXIT_OK)
        {
            LOG(VB_GENERAL, LOG_ERR,  QString("Failed to run %2 %3")
                .arg(cmd, args.join(" ")));
            return QString("Preview Generator failed for %1").arg(imagePath);
        }
 
        if (!image.load(im->m_thumbPath))
            return QString("Failed to open preview %1").arg(im->m_thumbPath);
    }
    else
    {
        return QString("Can't create thumbnail for type %1 (image %2)")
                .arg(im->m_type).arg(imagePath);
    }
 
    // Compensate for any Qt auto-orientation
    int orientBy = Orientation(im->m_orientation)
            .GetCurrent(im->m_type == kImageFile);
 
    // Orientate now to optimise load/display time - no orientation
    // is required when displaying thumbnails
    image = MythImage::ApplyExifOrientation(image, orientBy);
 
    // Create the thumbnail
    if (!image.save(im->m_thumbPath))
        return QString("Failed to create thumbnail %1").arg(im->m_thumbPath);
 
    LOG(VB_FILE, LOG_INFO,  QString("[%2] Created %1")
        .arg(im->m_thumbPath).arg(thumbPriority));
    return {};
}
 
 
template <class DBFS>
void ThumbThread<DBFS>::PauseBackground(bool pause)
{
    QMutexLocker locker(&m_mutex);
    m_doBackground = !pause;
 
    // restart if not already running
    if (m_doBackground && !this->isRunning())
        this->start();
}
 
 
template <class DBFS>
ImageThumb<DBFS>::ImageThumb(DBFS *const dbfs)
    : m_dbfs(*dbfs),
      m_imageThread(new ThumbThread<DBFS>("ImageThumbs", dbfs)),
      m_videoThread(new ThumbThread<DBFS>("VideoThumbs", dbfs))
{}
 
 
template <class DBFS>
ImageThumb<DBFS>::~ImageThumb()
{
    delete m_imageThread;
    delete m_videoThread;
    m_imageThread = m_videoThread = nullptr;
}
 
 
template <class DBFS>
void ImageThumb<DBFS>::ClearThumbs(int devId, const QString &action)
{
    // Cancel pending requests for the device
    // Waits for current generator task to complete
    if (m_imageThread)
        m_imageThread->AbortDevice(devId, action);
    if (m_videoThread)
        m_videoThread->AbortDevice(devId, action);
 
    // Remove devices now they are not in use
    QStringList mountPaths = m_dbfs.CloseDevices(devId, action);
//    if (mountPaths.isEmpty())
//        return;
 
    // Generate file & thumbnail urls (as per image cache) of mountpoints
    QStringList mesg;
    for (const auto& mount : std::as_const(mountPaths))
        mesg << m_dbfs.MakeFileUrl(mount)
             << m_dbfs.MakeThumbUrl(mount);
 
    // Notify clients to clear cache
    m_dbfs.Notify("IMAGE_DEVICE_CHANGED", mesg);
}
 
 
template <class DBFS>
QString ImageThumb<DBFS>::DeleteThumbs(const ImageList &images)
{
    // Determine affected images and redundant images/thumbnails
    QStringList ids;
 
    // Pictures & videos are deleted by their own threads
    ImageListK pics;
    ImageListK videos;
    for (const auto& im : std::as_const(images))
    {
        if (im->m_type == kVideoFile)
            videos.append(im);
        else
            pics.append(im);
 
        ids << QString::number(im->m_id);
    }
 
    if (!pics.isEmpty() && m_imageThread)
        m_imageThread->Enqueue(TaskPtr(new ThumbTask("DELETE", pics)));
    if (!videos.isEmpty() && m_videoThread)
        m_videoThread->Enqueue(TaskPtr(new ThumbTask("DELETE", videos)));
    return ids.join(",");
}
 
 
template <class DBFS>
void ImageThumb<DBFS>::CreateThumbnail(const ImagePtrK &im, int priority,
                                       bool notify)
{
    if (!im)
        return;
 
    // Allocate task a (hopefully) unique priority
    if (priority == kBackgroundPriority)
        priority = Priority(*im);
 
    TaskPtr task(new ThumbTask("CREATE", im, priority, notify));
 
    if (im->m_type == kImageFile && m_imageThread)
    {
        m_imageThread->Enqueue(task);
    }
    else if (im->m_type == kVideoFile && m_videoThread)
    {
        m_videoThread->Enqueue(task);
    }
    else
    {
        LOG(VB_FILE, LOG_INFO, QString("Ignoring create thumbnail %1, type %2")
            .arg(im->m_id).arg(im->m_type));
    }
}
 
 
template <class DBFS>
void ImageThumb<DBFS>::MoveThumbnail(const ImagePtrK &im)
{
    if (!im)
        return;
 
    TaskPtr task(new ThumbTask("MOVE", im));
 
    if (im->m_type == kImageFile && m_imageThread)
    {
        m_imageThread->Enqueue(task);
    }
    else if (im->m_type == kVideoFile && m_videoThread)
    {
        m_videoThread->Enqueue(task);
    }
    else
    {
        LOG(VB_FILE, LOG_INFO, QString("Ignoring move thumbnail %1, type %2")
            .arg(im->m_id).arg(im->m_type));
    }
}
 
 
template <class DBFS>
void ImageThumb<DBFS>::PauseBackground(bool pause)
{
    LOG(VB_FILE, LOG_INFO,  QString("Paused %1").arg(pause));
 
    if (m_imageThread)
        m_imageThread->PauseBackground(pause);
    if (m_videoThread)
        m_videoThread->PauseBackground(pause);
}
 
 
// Must define the valid template implementations to generate code for the
// instantiations (as they are defined in the cpp rather than header).
// Otherwise the linker will fail with undefined references...
#include "imagemanager.h"
template class ImageThumb<ImageDbLocal>;
template class ImageThumb<ImageDbSg>;