Source/core/dom/DocumentOrderedMap.cpp

/*
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 *
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 * modification, are permitted provided that the following conditions are
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#include "config.h"
#include "core/dom/DocumentOrderedMap.h"

#include "HTMLNames.h"
#include "core/dom/Element.h"
#include "core/dom/NodeTraversal.h"
#include "core/dom/TreeScope.h"
#include "core/html/HTMLLabelElement.h"
#include "core/html/HTMLMapElement.h"
#include "core/html/HTMLNameCollection.h"

namespace WebCore {

using namespace HTMLNames;

inline bool keyMatchesId(StringImpl* key, Element* element)
{
    return element->getIdAttribute().impl() == key;
}

inline bool keyMatchesName(StringImpl* key, Element* element)
{
    return element->getNameAttribute().impl() == key;
}

inline bool keyMatchesMapName(StringImpl* key, Element* element)
{
    return element->hasTagName(mapTag) && toHTMLMapElement(element)->getName().impl() == key;
}

inline bool keyMatchesLowercasedMapName(StringImpl* key, Element* element)
{
    return element->hasTagName(mapTag) && toHTMLMapElement(element)->getName().lower().impl() == key;
}

inline bool keyMatchesLabelForAttribute(StringImpl* key, Element* element)
{
    return isHTMLLabelElement(element) && element->getAttribute(forAttr).impl() == key;
}

void DocumentOrderedMap::clear()
{
    m_map.clear();
}

void DocumentOrderedMap::add(StringImpl* key, Element* element)
{
    ASSERT(key);
    ASSERT(element);

    Map::AddResult addResult = m_map.add(key, MapEntry(element));
    if (addResult.isNewEntry)
        return;

    MapEntry& entry = addResult.iterator->value;
    ASSERT(entry.count);
    entry.element = 0;
    entry.count++;
    entry.orderedList.clear();
}

void DocumentOrderedMap::remove(StringImpl* key, Element* element)
{
    ASSERT(key);
    ASSERT(element);

    Map::iterator it = m_map.find(key);
    ASSERT(it != m_map.end());
    MapEntry& entry = it->value;

    ASSERT(entry.count);
    if (entry.count == 1) {
        ASSERT(!entry.element || entry.element == element);
        m_map.remove(it);
    } else {
        if (entry.element == element)
            entry.element = 0;
        entry.count--;
        entry.orderedList.clear(); // FIXME: Remove the element instead if there are only few items left.
    }
}

template<bool keyMatches(StringImpl*, Element*)>
inline Element* DocumentOrderedMap::get(StringImpl* key, const TreeScope* scope) const
{
    ASSERT(key);
    ASSERT(scope);

    Map::iterator it = m_map.find(key);
    if (it == m_map.end())
        return 0;

    MapEntry& entry = it->value;
    ASSERT(entry.count);
    if (entry.element)
        return entry.element;

    // We know there's at least one node that matches; iterate to find the first one.
    for (Element* element = ElementTraversal::firstWithin(scope->rootNode()); element; element = ElementTraversal::next(element)) {
        if (!keyMatches(key, element))
            continue;
        entry.element = element;
        return element;
    }
    ASSERT_NOT_REACHED();
    return 0;
}

Element* DocumentOrderedMap::getElementById(StringImpl* key, const TreeScope* scope) const
{
    return get<keyMatchesId>(key, scope);
}

Element* DocumentOrderedMap::getElementByName(StringImpl* key, const TreeScope* scope) const
{
    return get<keyMatchesName>(key, scope);
}

Element* DocumentOrderedMap::getElementByMapName(StringImpl* key, const TreeScope* scope) const
{
    return get<keyMatchesMapName>(key, scope);
}

Element* DocumentOrderedMap::getElementByLowercasedMapName(StringImpl* key, const TreeScope* scope) const
{
    return get<keyMatchesLowercasedMapName>(key, scope);
}

Element* DocumentOrderedMap::getElementByLabelForAttribute(StringImpl* key, const TreeScope* scope) const
{
    return get<keyMatchesLabelForAttribute>(key, scope);
}

const Vector<Element*>* DocumentOrderedMap::getAllElementsById(StringImpl* key, const TreeScope* scope) const
{
    ASSERT(key);
    ASSERT(scope);

    Map::iterator it = m_map.find(key);
    if (it == m_map.end())
        return 0;

    MapEntry& entry = it->value;
    ASSERT(entry.count);
    if (!entry.count)
        return 0;

    if (entry.orderedList.isEmpty()) {
        entry.orderedList.reserveCapacity(entry.count);
        for (Element* element = entry.element ? entry.element : ElementTraversal::firstWithin(scope->rootNode()); element; element = ElementTraversal::next(element)) {
            if (!keyMatchesId(key, element))
                continue;
            entry.orderedList.append(element);
        }
        ASSERT(entry.orderedList.size() == entry.count);
    }

    return &entry.orderedList;
}

} // namespace WebCore