/*
 * Copyright (C) 2010 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. AND ITS CONTRIBUTORS ``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 ITS 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 "ResponsivenessTimer.h"

#include "WorkItem.h"

namespace WebKit {

static const double kResponsivenessTimeout = 3;

ResponsivenessTimer::ResponsivenessTimer(ResponsivenessTimer::Client* client)
    : m_client(client)
    , m_isResponsive(true)
    , m_timer(RunLoop::main(), this, &ResponsivenessTimer::timerFired)
{
}

ResponsivenessTimer::~ResponsivenessTimer()
{
    m_timer.stop();
}

void ResponsivenessTimer::invalidate()
{
    m_timer.stop();
}

void ResponsivenessTimer::timerFired()
{
    // We'll never schedule the timer unless we're responsive.
    ASSERT(m_isResponsive);
    
    m_isResponsive = false;
    m_client->didBecomeUnresponsive(this);

    m_timer.stop();
}
    
void ResponsivenessTimer::start()
{
    if (m_timer.isActive())
        return;

    if (!m_isResponsive)
        return;

    m_timer.startOneShot(kResponsivenessTimeout);
}

void ResponsivenessTimer::stop()
{
    if (!m_isResponsive) {
        // We got a life sign from the web process!
        m_client->didBecomeResponsive(this);
        m_isResponsive = true;
    }

    m_timer.stop();
}

} // namespace WebKit