/*
 * Copyright (c) 2008      Harry Bock <hbock@providence.edu>
 * Copyright (c) 2007      Gustavo Pichorim Boiko <gustavo.boiko@kdemail.net>
 * Copyright (c) 2002,2003 Hamish Rodda <rodda@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, write to the Free Software
 *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */

#include <KDebug>
#include <QWidget>
#include <QtGui/qx11info_x11.h>

#include "randrdisplay.h"
#include "randrscreen.h"


RandRDisplay::RandRDisplay()
    : m_valid(true)
{
    m_dpy = QX11Info::display();

    // Check extension
    if(XRRQueryExtension(m_dpy, &m_eventBase, &m_errorBase) == False) {
        m_valid = false;
        return;
    }

    int major_version, minor_version;
    XRRQueryVersion(m_dpy, &major_version, &minor_version);

    // check if we have the new version of the XRandR extension
    m_valid = (major_version > 1 || (major_version == 1 && minor_version >= 2));
    if (! m_valid) {
        return;
    }

    kDebug() << "XRANDR error code base: " << m_errorBase;
    m_numScreens = ScreenCount(m_dpy);
    m_currentScreenIndex = 0;

    // set the timestamp to 0
    RandR::timestamp = 0;

    // This assumption is WRONG with Xinerama
    // Q_ASSERT(QApplication::desktop()->numScreens() == ScreenCount(QX11Info::display()));
    for (int i = 0; i < m_numScreens; i++) {
            m_screens.append(new RandRScreen(i));
    }

    setCurrentScreen(DefaultScreen(QX11Info::display()));
}

RandRDisplay::~RandRDisplay()
{
    qDeleteAll(m_screens);
}

bool RandRDisplay::isValid() const
{
    return m_valid;
}

const QString& RandRDisplay::errorCode() const
{
    return m_errorCode;
}

int RandRDisplay::eventBase() const
{
    return m_eventBase;
}

int RandRDisplay::errorBase() const
{
    return m_errorBase;
}

const QString& RandRDisplay::version() const
{
    return m_version;
}

void RandRDisplay::setCurrentScreen(int index)
{
    Q_ASSERT(index < ScreenCount(m_dpy));
    m_currentScreenIndex = index;
}

int RandRDisplay::screenIndexOfWidget(QWidget* widget)
{
    // get info from Qt's X11 info directly; QDesktopWidget seems to use
    // Xinerama by default, which doesn't work properly with randr.
    // It will return more screens than exist for the display, causing
    // a crash in the screen/currentScreen methods.
    if(widget)
        return widget->x11Info().screen();

    return -1;
}

int RandRDisplay::currentScreenIndex() const
{
    return m_currentScreenIndex;
}

bool RandRDisplay::needsRefresh() const
{
    Time time, config_timestamp;
    time = XRRTimes(m_dpy, m_currentScreenIndex, &config_timestamp);

    kDebug() << "Cache:" << RandR::timestamp << "Server:" << time << "Config:" << config_timestamp;
    return (RandR::timestamp < time);
}

void RandRDisplay::refresh()
{
    foreach (RandRScreen* s, m_screens) {
        s->loadSettings();
    }
}

bool RandRDisplay::canHandle(const XEvent *e) const
{
    if (e->type == m_eventBase + RRScreenChangeNotify)
        return true;
    else if (e->type == m_eventBase + RRNotify)
        return true;
    return false;
}


void RandRDisplay::handleEvent(XEvent *e)
{
    if (e->type == m_eventBase + RRScreenChangeNotify) {
        XRRScreenChangeNotifyEvent *event = (XRRScreenChangeNotifyEvent*)(e);
        kDebug() << "RRScreenChangeNotify window: " << event->window << " root: " << event->root;
        for (int i=0; i < m_screens.count(); ++i) {
            RandRScreen *screen = m_screens.at(i);
            if (screen->rootWindow() == event->root)
                screen->handleEvent(event);
        }
    }
    else if (e->type == m_eventBase + RRNotify) {
        //forward the event to the right screen
        XRRNotifyEvent *event = (XRRNotifyEvent*)e;
        kDebug() << "RRNotify window: " << event->window;
        for (int i=0; i < m_screens.count(); ++i) {
            RandRScreen *screen = m_screens.at(i);
            // TODO: removed the window check because randr seems to pass an incorrect window
            // if ( screen->rootWindow() == event->window ) {
            screen->handleRandREvent(event);
            // }
        }
    }
    else {
        kDebug() << "RandRDisplay::handleEvent - Other";
    }
}

int RandRDisplay::numScreens() const
{
    Q_ASSERT(ScreenCount(QX11Info::display()) == m_numScreens);
    return m_numScreens;
}

RandRScreen* RandRDisplay::screen(int index)
{
    return m_screens.at(index);
}

RandRScreen* RandRDisplay::currentScreen()
{
    return m_screens.at(m_currentScreenIndex);
}