Source/WebCore/dom/WebKitNamedFlow.cpp

/*
 * Copyright (C) 2011 Adobe Systems Incorporated. All rights reserved.
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 * modification, are permitted provided that the following conditions
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#include "config.h"
#include "WebKitNamedFlow.h"

#include "RenderNamedFlowThread.h"
#include "RenderRegion.h"
#include "StaticNodeList.h"
#include "WebKitNamedFlowCollection.h"

namespace WebCore {

WebKitNamedFlow::WebKitNamedFlow(PassRefPtr<WebKitNamedFlowCollection> manager, const AtomicString& flowThreadName)
    : m_flowThreadName(flowThreadName)
    , m_flowManager(manager)
    , m_parentFlowThread(0)
    , m_state(FlowStateCreated)
{
}

WebKitNamedFlow::~WebKitNamedFlow()
{
    // The named flow is not "strong" referenced from anywhere at this time so it shouldn't be reused if the named flow is recreated.
    m_flowManager->discardNamedFlow(this);
}

PassRefPtr<WebKitNamedFlow> WebKitNamedFlow::create(PassRefPtr<WebKitNamedFlowCollection> manager, const AtomicString& flowThreadName)
{
    return adoptRef(new WebKitNamedFlow(manager, flowThreadName));
}

const AtomicString& WebKitNamedFlow::name() const
{
    return m_flowThreadName;
}

bool WebKitNamedFlow::overset() const
{
    if (m_flowManager->document())
        m_flowManager->document()->updateLayoutIgnorePendingStylesheets();

    // The renderer may be destroyed or created after the style update.
    // Because this is called from JS, where the wrapper keeps a reference to the NamedFlow, no guard is necessary.
    return m_parentFlowThread ? m_parentFlowThread->overset() : true;
}

static inline bool nodeInFlowThread(Node* contentNode, RenderNamedFlowThread* flowThread)
{
    return contentNode->renderer() && contentNode->renderer()->inRenderFlowThread() && flowThread == contentNode->renderer()->enclosingRenderFlowThread();
}

int WebKitNamedFlow::firstEmptyRegionIndex() const
{
    if (m_flowManager->document())
        m_flowManager->document()->updateLayoutIgnorePendingStylesheets();

    if (!m_parentFlowThread)
        return -1;

    const RenderRegionList& regionList = m_parentFlowThread->renderRegionList();
    if (regionList.isEmpty())
        return -1;
    RenderRegionList::const_iterator iter = regionList.begin();
    for (int index = 0; iter != regionList.end(); ++index, ++iter) {
        const RenderRegion* renderRegion = *iter;
        if (renderRegion->regionState() == RenderRegion::RegionEmpty)
            return index;
    }
    return -1;
}

PassRefPtr<NodeList> WebKitNamedFlow::getRegionsByContent(Node* contentNode)
{
    Vector<RefPtr<Node> > regionNodes;

    if (!contentNode)
        return StaticNodeList::adopt(regionNodes);

    if (m_flowManager->document())
        m_flowManager->document()->updateLayoutIgnorePendingStylesheets();

    // The renderer may be destroyed or created after the style update.
    // Because this is called from JS, where the wrapper keeps a reference to the NamedFlow, no guard is necessary.
    if (!m_parentFlowThread)
        return StaticNodeList::adopt(regionNodes);

    if (nodeInFlowThread(contentNode, m_parentFlowThread)) {
        const RenderRegionList& regionList = m_parentFlowThread->renderRegionList();
        for (RenderRegionList::const_iterator iter = regionList.begin(); iter != regionList.end(); ++iter) {
            const RenderRegion* renderRegion = *iter;
            if (!renderRegion->isValid())
                continue;
            if (m_parentFlowThread->objectInFlowRegion(contentNode->renderer(), renderRegion))
                regionNodes.append(renderRegion->node());
        }
    }

    return StaticNodeList::adopt(regionNodes);
}

PassRefPtr<NodeList> WebKitNamedFlow::getContent()
{
    Vector<RefPtr<Node> > contentNodes;

    if (m_flowManager->document())
        m_flowManager->document()->updateLayoutIgnorePendingStylesheets();

    // The renderer may be destroyed or created after the style update.
    // Because this is called from JS, where the wrapper keeps a reference to the NamedFlow, no guard is necessary.
    if (!m_parentFlowThread)
        return StaticNodeList::adopt(contentNodes);

    const NamedFlowContentNodes& contentNodesList = m_parentFlowThread->contentNodes();
    for (NamedFlowContentNodes::const_iterator it = contentNodesList.begin(); it != contentNodesList.end(); ++it) {
        Node* node = *it;
        ASSERT(node->computedStyle()->flowThread() == m_parentFlowThread->flowThreadName());
        contentNodes.append(node);
    }

    return StaticNodeList::adopt(contentNodes);
}

void WebKitNamedFlow::setRenderer(RenderNamedFlowThread* parentFlowThread)
{
    // The named flow can either go from a no_renderer->renderer or renderer->no_renderer state; anything else could indicate a bug.
    ASSERT((!m_parentFlowThread && parentFlowThread) || (m_parentFlowThread && !parentFlowThread));

    // If parentFlowThread is 0, the flow thread will move in the "NULL" state"
    m_parentFlowThread = parentFlowThread;
}

} // namespace WebCore