/**

 * This file is part of the KDE libraries

 *

 * Comic Book Thumbnailer for KDE 4 v0.1

 * Creates cover page previews for comic-book files (.cbr/z/t).

 * SPDX-FileCopyrightText: 2009 Harsh J <harsh@harshj.com>

 *

 * Some code borrowed from Okular's comicbook generators,

 * by Tobias Koenig <tokoe@kde.org>

 *

 * SPDX-License-Identifier: GPL-2.0-only OR GPL-3.0-only OR LicenseRef-KDE-Accepted-GPL

 */

// comiccreator.cpp

#include "comiccreator.h"

#include "thumbnail-comic-logsettings.h"

#include <K7Zip>

#include <KPluginFactory>

#include <KTar>

#include <KZip>

#include <memory>

#include <QEventLoop>

#include <QFile>

#include <QMimeDatabase>

#include <QMimeType>

#include <QProcess>

#include <QStandardPaths>

#include <QTemporaryDir>

K_PLUGIN_CLASS_WITH_JSON(ComicCreator, "comicbookthumbnail.json")

Unexecuted instantiation: comicbookthumbnail_factory::tr(char const*, char const*, int)

Unexecuted instantiation: comicbookthumbnail_factory::~comicbookthumbnail_factory()

ComicCreator::ComicCreator(QObject *parent, const QVariantList &args)

    : KIO::ThumbnailCreator(parent, args)

{

}

KIO::ThumbnailResult ComicCreator::create(const KIO::ThumbnailRequest &request)

{

    const QString path = request.url().toLocalFile();

    QImage cover;

    // Detect mime type.

    QMimeDatabase db;

    const QMimeType mime = db.mimeTypeForName(request.mimeType());

    if (mime.inherits("application/x-cbz") || mime.inherits("application/zip")) {

        // ZIP archive.

        cover = extractArchiveImage(path, ZIP);

    } else if (mime.inherits("application/x-cbt") || mime.inherits("application/x-gzip") || mime.inherits("application/x-tar")) {

        // TAR archive

        cover = extractArchiveImage(path, TAR);

    } else if (mime.inherits("application/x-cb7") || mime.inherits("application/x-7z-compressed")) {

        cover = extractArchiveImage(path, SEVENZIP);

    } else if (mime.inherits("application/x-cbr") || mime.inherits("application/x-rar")) {

        // RAR archive.

        cover = extractRARImage(path);

    }

    if (cover.isNull()) {

        qCDebug(KIO_THUMBNAIL_COMIC_LOG) << "Error creating the comic book thumbnail for" << path;

        return KIO::ThumbnailResult::fail();

    }

    return KIO::ThumbnailResult::pass(cover);

}

void ComicCreator::filterImages(QStringList &entries)

{

    /// Sort case-insensitive, then remove non-image entries.

    QMap<QString, QString> entryMap;

    for (const QString &entry : qAsConst(entries)) {

        // Skip MacOS resource forks

        if (entry.startsWith(QLatin1String("__MACOSX"), Qt::CaseInsensitive) || entry.startsWith(QLatin1String(".DS_Store"), Qt::CaseInsensitive)) {

            continue;

        }

        if (entry.endsWith(QLatin1String(".avif"), Qt::CaseInsensitive) || entry.endsWith(QLatin1String(".bmp"), Qt::CaseInsensitive)

            || entry.endsWith(QLatin1String(".gif"), Qt::CaseInsensitive) || entry.endsWith(QLatin1String(".heif"), Qt::CaseInsensitive)

            || entry.endsWith(QLatin1String(".jpg"), Qt::CaseInsensitive) || entry.endsWith(QLatin1String(".jpeg"), Qt::CaseInsensitive)

            || entry.endsWith(QLatin1String(".jxl"), Qt::CaseInsensitive) || entry.endsWith(QLatin1String(".png"), Qt::CaseInsensitive)

            || entry.endsWith(QLatin1String(".webp"), Qt::CaseInsensitive)) {

            entryMap.insert(entry.toLower(), entry);

        }

    }

    entries = entryMap.values();

}

QImage ComicCreator::extractArchiveImage(const QString &path, const ComicCreator::Type type)

{

    /// Extracts the cover image out of the .cbz or .cbt file.

    QScopedPointer<KArchive> cArchive;

    if (type == ZIP) {

        // Open the ZIP archive.

        cArchive.reset(new KZip(path));

    } else if (type == TAR) {

        // Open the TAR archive.

        cArchive.reset(new KTar(path));

    } else if (type == SEVENZIP) {

        // Open the 7z archive.

        cArchive.reset(new K7Zip(path));

    } else {

        // Reject all other types for this method.

        return QImage();

    }

    // Can our archive be opened?

    if (!cArchive->open(QIODevice::ReadOnly)) {

        return QImage();

    }

    // Get the archive's directory.

    const KArchiveDirectory *cArchiveDir = nullptr;

    cArchiveDir = cArchive->directory();

    if (!cArchiveDir) {

        return QImage();

    }

    QStringList entries;

    // Get and filter the entries from the archive.

    getArchiveFileList(entries, QString(), cArchiveDir);

    filterImages(entries);

    if (entries.isEmpty()) {

        return QImage();

    }

    // Extract the cover file.

    const KArchiveFile *coverFile = static_cast<const KArchiveFile *>(cArchiveDir->entry(entries[0]));

    if (!coverFile) {

        return QImage();

    }

    return QImage::fromData(coverFile->data());

}

void ComicCreator::getArchiveFileList(QStringList &entries, const QString &prefix, const KArchiveDirectory *dir)

{

    /// Recursively list all files in the ZIP archive into 'entries'.

    const auto dirEntries = dir->entries();

    for (const QString &entry : dirEntries) {

        const KArchiveEntry *e = dir->entry(entry);

        if (e->isDirectory()) {

            getArchiveFileList(entries, prefix + entry + '/', static_cast<const KArchiveDirectory *>(e));

        } else if (e->isFile()) {

            entries.append(prefix + entry);

        }

    }

}

QImage ComicCreator::extractRARImage(const QString &path)

{

    /// Extracts the cover image out of the .cbr file.

    // Check if unrar is available. Get its path in 'unrarPath'.

    static const QString unrar = unrarPath();

    if (unrar.isEmpty()) {

        return QImage();

    }

    // Get the files and filter the images out.

    QStringList entries = getRARFileList(path, unrar);

    filterImages(entries);

    if (entries.isEmpty()) {

        return QImage();

    }

    // Extract the cover file alone. Use verbose paths.

    // unrar x -n<file> path/to/archive /path/to/temp

    QTemporaryDir cUnrarTempDir;

    runProcess(unrar, {"x", "-n" + entries[0], path, cUnrarTempDir.path()});

    // Load cover file data into image.

    QImage cover;

    cover.load(cUnrarTempDir.path() + QDir::separator() + entries[0]);

    return cover;

}

QStringList ComicCreator::getRARFileList(const QString &path, const QString &unrarPath)

{

    /// Get a verbose unrar listing so we can extract a single file later.

    // CMD: unrar vb /path/to/archive

    QStringList entries;

    runProcess(unrarPath, {"vb", path});

    entries = QString::fromLocal8Bit(m_stdOut).split('\n', Qt::SkipEmptyParts);

    return entries;

}

QString ComicCreator::unrarPath() const

{

    /// Check the standard paths to see if a suitable unrar is available.

    QString unrar = QStandardPaths::findExecutable("unrar");

    if (unrar.isEmpty()) {

        unrar = QStandardPaths::findExecutable("unrar-nonfree");

    }

    if (unrar.isEmpty()) {

        unrar = QStandardPaths::findExecutable("rar");

    }

    if (!unrar.isEmpty()) {

        QProcess proc;

        proc.start(unrar, {"-version"});

        proc.waitForFinished(-1);

        const QStringList lines = QString::fromLocal8Bit(proc.readAllStandardOutput()).split('\n', Qt::SkipEmptyParts);

        if (!lines.isEmpty()) {

            if (lines.first().startsWith(QLatin1String("RAR ")) || lines.first().startsWith(QLatin1String("UNRAR "))) {

                return unrar;

            }

        }

    }

    qCWarning(KIO_THUMBNAIL_COMIC_LOG) << "A suitable version of unrar is not available.";

    return QString();

}

int ComicCreator::runProcess(const QString &processPath, const QStringList &args)

{

    /// Run a process and store stdout data in a buffer.

    QProcess process;

    process.setProcessChannelMode(QProcess::SeparateChannels);

    process.setProgram(processPath);

    process.setArguments(args);

    process.start(QIODevice::ReadWrite | QIODevice::Unbuffered);

    auto ret = process.waitForFinished(-1);

    m_stdOut = process.readAllStandardOutput();

    return ret;

}

#include "comiccreator.moc"

#include "moc_comiccreator.cpp"