/*
    Scan Tailor - Interactive post-processing tool for scanned pages.
    Copyright (C)  Joseph Artsimovich <joseph.artsimovigh@gmail.com>

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#include "config.h"
#include "ImageLoader.h"
#include "TiffReader.h"
#ifdef ENABLE_MUPDF
#include "PdfReader.h"
#endif
#ifdef ENABLE_OPENJPEG
#include "Jp2Reader.h"
#endif
#include "ImageId.h"
#include <QImageReader>
#include <QImage>
#include <QString>
#include <QIODevice>
#include <QFile>

QImage
ImageLoader::load(ImageId const& image_id)
{
    return load(image_id.filePath(), image_id.zeroBasedPage());
}

QImage
ImageLoader::load(QString const& file_path, int const page_num)
{
    QFile file(file_path);
    if (!file.open(QIODevice::ReadOnly)) {
        return QImage();
    }

    if (file_path.startsWith(":")) {
        // internally empty pages are represented as multipage image although they're just links to the same single page image in app resources
        return load(file, 0);
    }

    return load(file, page_num);
}

QImage
ImageLoader::load(QIODevice& io_dev, int const page_num)
{
#ifdef ENABLE_MUPDF
    if (PdfReader::canRead(io_dev)) {
        return PdfReader::readImage(io_dev, page_num);
    }
#endif

    if (TiffReader::canRead(io_dev)) {
        return TiffReader::readImage(io_dev, page_num);
    }

    if (page_num != 0) {
        // Qt can only load the first page of multi-page images.
        return QImage();
    }

#ifdef ENABLE_OPENJPEG
    if (Jp2Reader::canRead(io_dev)) {
        return Jp2Reader::readImage(io_dev);
    }
#endif

    QImage image;
    QImageReader(&io_dev).read(&image);
    return image;
}
