/*

 * Copyright (C) 2009 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 COMPUTER, 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 COMPUTER, 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 "CachedPage.h"

#include "CachedFramePlatformData.h"

#include "DocumentLoader.h"

#include "ExceptionCode.h"

#include "EventNames.h"

#include "Frame.h"

#include "FrameLoaderClient.h"

#include "FrameView.h"

#include "Logging.h"

#include "PageTransitionEvent.h"

#include <wtf/text/CString.h>

#include <wtf/RefCountedLeakCounter.h>

#if ENABLE(SVG)

#include "SVGDocumentExtensions.h"

#endif

#if ENABLE(TOUCH_EVENTS)

#include "Chrome.h"

#include "ChromeClient.h"

#include "Page.h"

#endif

namespace WebCore {

#ifndef NDEBUG

static WTF::RefCountedLeakCounter& cachedFrameCounter()

{

    DEFINE_STATIC_LOCAL(WTF::RefCountedLeakCounter, counter, ("CachedFrame"));

    return counter;

}

#endif

CachedFrameBase::CachedFrameBase(Frame* frame)

    : m_document(frame->document())

    , m_documentLoader(frame->loader()->documentLoader())

    , m_view(frame->view())

    , m_mousePressNode(frame->eventHandler()->mousePressNode())

    , m_url(frame->loader()->url())

    , m_isMainFrame(!frame->tree()->parent())

{

}

CachedFrameBase::~CachedFrameBase()

{

#ifndef NDEBUG

    cachedFrameCounter().decrement();

#endif

    // CachedFrames should always have had destroy() called by their parent CachedPage

    ASSERT(!m_document);

}

void CachedFrameBase::restore()

{

    ASSERT(m_document->view() == m_view);

    Frame* frame = m_view->frame();

    m_cachedFrameScriptData->restore(frame);

#if ENABLE(SVG)

    if (m_document->svgExtensions())

        m_document->accessSVGExtensions()->unpauseAnimations();

#endif

    frame->animation()->resumeAnimations(m_document.get());

    frame->eventHandler()->setMousePressNode(m_mousePressNode.get());

    m_document->resumeActiveDOMObjects();

    // It is necessary to update any platform script objects after restoring the

    // cached page.

    frame->script()->updatePlatformScriptObjects();

    // Reconstruct the FrameTree

    for (unsigned i = 0; i < m_childFrames.size(); ++i)

        frame->tree()->appendChild(m_childFrames[i]->view()->frame());

    // Open the child CachedFrames in their respective FrameLoaders.

    for (unsigned i = 0; i < m_childFrames.size(); ++i)

        m_childFrames[i]->open();

    m_document->enqueuePageshowEvent(PageshowEventPersisted);

#if ENABLE(TOUCH_EVENTS)

    if (m_document->hasListenerType(Document::TOUCH_LISTENER))

        m_document->page()->chrome()->client()->needTouchEvents(true);

#endif

}

CachedFrame::CachedFrame(Frame* frame)

    : CachedFrameBase(frame)

{

#ifndef NDEBUG

    cachedFrameCounter().increment();

#endif

    ASSERT(m_document);

    ASSERT(m_documentLoader);

    ASSERT(m_view);

    // Active DOM objects must be suspended before we cached the frame script data

    m_document->suspendActiveDOMObjects();

    m_cachedFrameScriptData = adoptPtr(new ScriptCachedFrameData(frame));

    // Custom scrollbar renderers will get reattached when the document comes out of the page cache

    m_view->detachCustomScrollbars();

    m_document->documentWillBecomeInactive();

    frame->clearTimers();

    m_document->setInPageCache(true);

    frame->loader()->stopLoading(UnloadEventPolicyUnloadAndPageHide);

    frame->loader()->client()->savePlatformDataToCachedFrame(this);

    // Create the CachedFrames for all Frames in the FrameTree.

    for (Frame* child = frame->tree()->firstChild(); child; child = child->tree()->nextSibling())

        m_childFrames.append(CachedFrame::create(child));

    // Deconstruct the FrameTree, to restore it later.

    // We do this for two reasons:

    // 1 - We reuse the main frame, so when it navigates to a new page load it needs to start with a blank FrameTree.

    // 2 - It's much easier to destroy a CachedFrame while it resides in the PageCache if it is disconnected from its parent.

    for (unsigned i = 0; i < m_childFrames.size(); ++i)

        frame->tree()->removeChild(m_childFrames[i]->view()->frame());

    if (!m_isMainFrame)

        frame->page()->decrementFrameCount();

#ifndef NDEBUG

    if (m_isMainFrame)

        LOG(PageCache, "Finished creating CachedFrame for main frame url '%s' and DocumentLoader %p\n", m_url.string().utf8().data(), m_documentLoader.get());

    else

        LOG(PageCache, "Finished creating CachedFrame for child frame with url '%s' and DocumentLoader %p\n", m_url.string().utf8().data(), m_documentLoader.get());

#endif

#if ENABLE(TOUCH_EVENTS)

    if (m_document->hasListenerType(Document::TOUCH_LISTENER))

        m_document->page()->chrome()->client()->needTouchEvents(false);

#endif

}

void CachedFrame::open()

{

    ASSERT(m_view);

    m_view->frame()->loader()->open(*this);

    if (!m_isMainFrame)

        m_view->frame()->page()->incrementFrameCount();

}

void CachedFrame::clear()

{

    if (!m_document)

        return;

    // clear() should only be called for Frames representing documents that are no longer in the page cache.

    // This means the CachedFrame has been:

    // 1 - Successfully restore()'d by going back/forward.

    // 2 - destroy()'ed because the PageCache is pruning or the WebView was closed.

    ASSERT(!m_document->inPageCache());

    ASSERT(m_view);

    ASSERT(m_document->frame() == m_view->frame());

    for (int i = m_childFrames.size() - 1; i >= 0; --i)

        m_childFrames[i]->clear();

    m_document = 0;

    m_view = 0;

    m_mousePressNode = 0;

    m_url = KURL();

    m_cachedFramePlatformData.clear();

    m_cachedFrameScriptData.clear();

}

void CachedFrame::destroy()

{

    if (!m_document)

        return;

    // Only CachedFrames that are still in the PageCache should be destroyed in this manner

    ASSERT(m_document->inPageCache());

    ASSERT(m_view);

    ASSERT(m_document->frame() == m_view->frame());

    if (!m_isMainFrame) {

        m_view->frame()->detachFromPage();

        m_view->frame()->loader()->detachViewsAndDocumentLoader();

    }

    for (int i = m_childFrames.size() - 1; i >= 0; --i)

        m_childFrames[i]->destroy();

    if (m_cachedFramePlatformData)

        m_cachedFramePlatformData->clear();

    Frame::clearTimers(m_view.get(), m_document.get());

    // FIXME: Why do we need to call removeAllEventListeners here? When the document is in page cache, this method won't work

    // fully anyway, because the document won't be able to access its DOMWindow object (due to being frameless).

    m_document->removeAllEventListeners();

    m_document->setInPageCache(false);

    // FIXME: We don't call willRemove here. Why is that OK?

    m_document->detach();

    m_view->clearFrame();

    clear();

}

void CachedFrame::setCachedFramePlatformData(PassOwnPtr<CachedFramePlatformData> data)

{

    m_cachedFramePlatformData = data;

}

CachedFramePlatformData* CachedFrame::cachedFramePlatformData()

{

    return m_cachedFramePlatformData.get();

}

int CachedFrame::descendantFrameCount() const

{

    int count = m_childFrames.size();

    for (size_t i = 0; i < m_childFrames.size(); ++i)

        count += m_childFrames[i]->descendantFrameCount();

    return count;

}

} // namespace WebCore