/*

 * 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 "RunLoop.h"

#include "WorkItem.h"

static const UINT PerformWorkMessage = WM_USER + 1;

static const LPWSTR kRunLoopMessageWindowClassName = L"RunLoopMessageWindow";

LRESULT CALLBACK RunLoop::RunLoopWndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)

{

    LONG_PTR longPtr = ::GetWindowLongPtr(hWnd, 0);

    if (RunLoop* runLoop = reinterpret_cast<RunLoop*>(longPtr))

        return runLoop->wndProc(hWnd, message, wParam, lParam);

    if (message == WM_CREATE) {

        LPCREATESTRUCT createStruct = reinterpret_cast<LPCREATESTRUCT>(lParam);

        // Associate the RunLoop with the window.

        ::SetWindowLongPtr(hWnd, 0, (LONG_PTR)createStruct->lpCreateParams);

        return 0;

    }

    return ::DefWindowProc(hWnd, message, wParam, lParam);

}

LRESULT RunLoop::wndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)

{

    switch (message) {

    case PerformWorkMessage:

        performWork();

        return 0;

    case WM_TIMER:

        RunLoop::TimerBase::timerFired(this, wParam);

        return 0;

    }

    return ::DefWindowProc(hWnd, message, wParam, lParam);

}

void RunLoop::run()

{

    MSG message;

    while (BOOL result = ::GetMessage(&message, 0, 0, 0)) {

        if (result == -1)

            break;

        ::TranslateMessage(&message);

        ::DispatchMessage(&message);

    }

}

void RunLoop::stop()

{

    ::PostQuitMessage(0);

}

bool RunLoop::registerRunLoopMessageWindowClass()

{

    // FIXME: This really only needs to be called once.

    WNDCLASSEX windowClass = { 0 };

    windowClass.cbSize          = sizeof(windowClass);

    windowClass.lpfnWndProc     = RunLoop::RunLoopWndProc;

    windowClass.cbWndExtra      = sizeof(RunLoop*);

    windowClass.lpszClassName   = kRunLoopMessageWindowClassName;

    return !!::RegisterClassEx(&windowClass);

}

RunLoop::RunLoop()

{

    registerRunLoopMessageWindowClass();

    m_runLoopMessageWindow = ::CreateWindow(kRunLoopMessageWindowClassName, 0, 0,

                                            CW_USEDEFAULT, 0, CW_USEDEFAULT, 0,

                                            HWND_MESSAGE, 0, 0, this);

    ASSERT(::IsWindow(m_runLoopMessageWindow));

}

RunLoop::~RunLoop()

{

    // FIXME: Tear down the work item queue here.

}

void RunLoop::wakeUp()

{

    // FIXME: No need to wake up the run loop if we've already called scheduleWork

    // before the run loop has had the time to respond.

    ::PostMessage(m_runLoopMessageWindow, PerformWorkMessage, reinterpret_cast<WPARAM>(this), 0);

}

// RunLoop::Timer

void RunLoop::TimerBase::timerFired(RunLoop* runLoop, uint64_t ID)

{

    TimerMap::iterator it = runLoop->m_activeTimers.find(ID);

    ASSERT(it != runLoop->m_activeTimers.end());

    TimerBase* timer = it->second;

    timer->fired();

}

static uint64_t generateTimerID()

{

    static uint64_t uniqueTimerID = 1;

    return uniqueTimerID++;

}

RunLoop::TimerBase::TimerBase(RunLoop* runLoop)

    : m_runLoop(runLoop)

    , m_ID(generateTimerID())

{

}

RunLoop::TimerBase::~TimerBase()

{

    stop();

}

void RunLoop::TimerBase::start(double nextFireInterval, double /*repeatInterval*/)

{

    // FIMXE: Support repeating timers.

    m_runLoop->m_activeTimers.set(m_ID, this);

    ::SetTimer(m_runLoop->m_runLoopMessageWindow, m_ID, nextFireInterval, 0);

}

void RunLoop::TimerBase::stop()

{

    TimerMap::iterator it = m_runLoop->m_activeTimers.find(m_ID);

    if (it == m_runLoop->m_activeTimers.end())

        return;

    m_runLoop->m_activeTimers.remove(it);

    ::KillTimer(m_runLoop->m_runLoopMessageWindow, m_ID);

}

bool RunLoop::TimerBase::isActive() const

{

    return m_runLoop->m_activeTimers.contains(m_ID);

}