/********************************************************************
 KWin - the KDE window manager
 This file is part of the KDE project.

Copyright (C) 2014 Martin Gräßlin <mgraesslin@kde.org>

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 2 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 "buffer_interface.h"
#include "surface_interface.h"

namespace KWin
{
namespace WaylandServer
{

BufferInterface::BufferInterface(wl_resource *resource, SurfaceInterface *parent)
    : QObject(parent)
    , m_buffer(resource)
    , m_shmBuffer(wl_shm_buffer_get(m_buffer))
    , m_surface(parent)
    , m_refCount(0)
{
}

BufferInterface::~BufferInterface()
{
    Q_ASSERT(m_refCount == 0);
    releaseImage();
}

void BufferInterface::releaseImage()
{
    if (m_image.isNull()) {
        return;
    }
    // first destroy it
    m_image = QImage();
    wl_shm_buffer_end_access(m_shmBuffer);
}

void BufferInterface::ref()
{
    m_refCount++;
}

void BufferInterface::unref()
{
    Q_ASSERT(m_refCount > 0);
    m_refCount--;
    if (m_refCount == 0) {
        releaseImage();
        wl_buffer_send_release(m_buffer);
        deleteLater();
    }
}

QImage::Format BufferInterface::format() const
{
    switch (wl_shm_buffer_get_format(m_shmBuffer)) {
    case WL_SHM_FORMAT_ARGB8888:
        return QImage::Format_ARGB32;
    case WL_SHM_FORMAT_XRGB8888:
        return QImage::Format_RGB32;
    default:
        return QImage::Format_Invalid;
    }
}

QImage BufferInterface::data()
{
    if (m_image.isNull()) {
        createImage();
    }
    return m_image;
}

void BufferInterface::createImage()
{
    if (!m_shmBuffer) {
        return;
    }
    const QImage::Format imageFormat = format();
    if (imageFormat == QImage::Format_Invalid) {
        return;
    }
    wl_shm_buffer_begin_access(m_shmBuffer);
    m_image = QImage((const uchar*)wl_shm_buffer_get_data(m_shmBuffer),
                     wl_shm_buffer_get_width(m_shmBuffer),
                     wl_shm_buffer_get_height(m_shmBuffer),
                     wl_shm_buffer_get_stride(m_shmBuffer),
                     imageFormat);
}

}
}