/*
 * Copyright (C) 2010, 2014 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
 */

#include "config.h"
#include "DisplayRefreshMonitorManager.h"

#if USE(REQUEST_ANIMATION_FRAME_DISPLAY_MONITOR)

#include "DisplayRefreshMonitor.h"
#include "DisplayRefreshMonitorClient.h"
#include <wtf/CurrentTime.h>

namespace WebCore {

DisplayRefreshMonitorManager::~DisplayRefreshMonitorManager()
{
}

DisplayRefreshMonitorManager& DisplayRefreshMonitorManager::sharedManager()
{
    static NeverDestroyed<DisplayRefreshMonitorManager> manager;
    return manager.get();
}

DisplayRefreshMonitor* DisplayRefreshMonitorManager::createMonitorForClient(DisplayRefreshMonitorClient& client)
{
    PlatformDisplayID clientDisplayID = client.displayID();
    for (const RefPtr<DisplayRefreshMonitor>& monitor : m_monitors) {
        if (monitor->displayID() != clientDisplayID)
            continue;
        monitor->addClient(client);
        return monitor.get();
    }

    RefPtr<DisplayRefreshMonitor> monitor = DisplayRefreshMonitor::create(client);
    if (!monitor)
        return nullptr;

    monitor->addClient(client);
    DisplayRefreshMonitor* result = monitor.get();
    m_monitors.append(monitor.release());
    return result;
}

void DisplayRefreshMonitorManager::registerClient(DisplayRefreshMonitorClient& client)
{
    if (!client.hasDisplayID())
        return;

    createMonitorForClient(client);
}

void DisplayRefreshMonitorManager::unregisterClient(DisplayRefreshMonitorClient& client)
{
    if (!client.hasDisplayID())
        return;

    PlatformDisplayID clientDisplayID = client.displayID();
    for (size_t i = 0; i < m_monitors.size(); ++i) {
        RefPtr<DisplayRefreshMonitor> monitor = m_monitors[i];
        if (monitor->displayID() != clientDisplayID)
            continue;
        if (monitor->removeClient(client)) {
            if (!monitor->hasClients())
                m_monitors.remove(i);
        }
        return;
    }
}

bool DisplayRefreshMonitorManager::scheduleAnimation(DisplayRefreshMonitorClient& client)
{
    if (!client.hasDisplayID())
        return false;

    DisplayRefreshMonitor* monitor = createMonitorForClient(client);
    if (!monitor)
        return false;

    client.setIsScheduled(true);
    return monitor->requestRefreshCallback();
}

void DisplayRefreshMonitorManager::displayDidRefresh(DisplayRefreshMonitor& monitor)
{
    if (!monitor.shouldBeTerminated())
        return;

    size_t monitorIndex = m_monitors.find(&monitor);
    ASSERT(monitorIndex != notFound);
    m_monitors.remove(monitorIndex);
}

void DisplayRefreshMonitorManager::windowScreenDidChange(PlatformDisplayID displayID, DisplayRefreshMonitorClient& client)
{
    if (client.hasDisplayID() && client.displayID() == displayID)
        return;
    
    unregisterClient(client);
    client.setDisplayID(displayID);
    registerClient(client);
    if (client.isScheduled())
        scheduleAnimation(client);
}

}

#endif // USE(REQUEST_ANIMATION_FRAME_DISPLAY_MONITOR)
