Source/core/html/HTMLSelectElement.cpp

/* [<][>][^][v][top][bottom][index][help] */
This source file includes following definitions.
m_suggestedIndex
create
create
formControlType
optionSelectedByUser
hasPlaceholderLabelOption
validationMessage
valueMissing
listBoxSelectItem
usesMenuList
activeSelectionStartListIndex
activeSelectionEndListIndex
add
addBeforeOptionAtIndex
remove
value
setValue
suggestedValue
setSuggestedValue
isPresentationAttribute
parseAttribute
shouldShowFocusRingOnMouseFocus
canSelectAll
createRenderer
selectedOptions
options
updateListItemSelectedStates
childrenChanged
optionElementChildrenChanged
accessKeyAction
setMultiple
setSize
namedItem
item
setOption
setLength
isRequiredFormControl
nextValidIndex
nextSelectableListIndex
previousSelectableListIndex
firstSelectableListIndex
lastSelectableListIndex
nextSelectableListIndexPageAway
selectAll
saveLastSelection
setActiveSelectionAnchorIndex
setActiveSelectionEndIndex
updateListBoxSelection
listBoxOnChange
dispatchInputAndChangeEventForMenuList
scrollToSelection
setOptionsChangedOnRenderer
listItems
invalidateSelectedItems
setRecalcListItems
recalcListItems
selectedIndex
setSelectedIndex
suggestedIndex
setSuggestedIndex
optionSelectionStateChanged
selectOption
optionToListIndex
listToOptionIndex
dispatchFocusEvent
dispatchBlurEvent
deselectItemsWithoutValidation
saveFormControlState
searchOptionsForValue
restoreFormControlState
parseMultipleAttribute
appendFormData
resetImpl
platformHandleKeydownEvent
menuListDefaultEventHandler
updateSelectedState
listBoxDefaultEventHandler
defaultEventHandler
lastSelectedListIndex
indexOfSelectedOption
optionCount
optionAtIndex
typeAheadFind
insertedInto
accessKeySetSelectedIndex
length
finishParsingChildren
anonymousIndexedSetter
isInteractiveContent
supportsAutofocus
/*
 * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
 * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
 *           (C) 1999 Antti Koivisto (koivisto@kde.org)
 *           (C) 2001 Dirk Mueller (mueller@kde.org)
 * Copyright (C) 2004, 2005, 2006, 2007, 2009, 2010, 2011 Apple Inc. All rights reserved.
 *           (C) 2006 Alexey Proskuryakov (ap@nypop.com)
 * Copyright (C) 2010 Google Inc. All rights reserved.
 * Copyright (C) 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public License
 * along with this library; see the file COPYING.LIB.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA 02110-1301, USA.
 *
 */

#include "config.h"
#include "core/html/HTMLSelectElement.h"

#include "HTMLNames.h"
#include "bindings/v8/ExceptionMessages.h"
#include "bindings/v8/ExceptionState.h"
#include "bindings/v8/ExceptionStatePlaceholder.h"
#include "core/accessibility/AXObjectCache.h"
#include "core/dom/Attribute.h"
#include "core/dom/ElementTraversal.h"
#include "core/dom/NodeTraversal.h"
#include "core/events/GestureEvent.h"
#include "core/events/KeyboardEvent.h"
#include "core/events/MouseEvent.h"
#include "core/frame/LocalFrame.h"
#include "core/html/FormDataList.h"
#include "core/html/HTMLFormElement.h"
#include "core/html/HTMLOptionElement.h"
#include "core/html/forms/FormController.h"
#include "core/page/EventHandler.h"
#include "core/page/SpatialNavigation.h"
#include "core/rendering/RenderListBox.h"
#include "core/rendering/RenderMenuList.h"
#include "core/rendering/RenderTheme.h"
#include "platform/PlatformMouseEvent.h"
#include "platform/text/PlatformLocale.h"

using namespace std;
using namespace WTF::Unicode;

namespace WebCore {

using namespace HTMLNames;

// Upper limit agreed upon with representatives of Opera and Mozilla.
static const unsigned maxSelectItems = 10000;

HTMLSelectElement::HTMLSelectElement(Document& document, HTMLFormElement* form)
    : HTMLFormControlElementWithState(selectTag, document, form)
    , m_typeAhead(this)
    , m_size(0)
    , m_lastOnChangeIndex(-1)
    , m_activeSelectionAnchorIndex(-1)
    , m_activeSelectionEndIndex(-1)
    , m_isProcessingUserDrivenChange(false)
    , m_multiple(false)
    , m_activeSelectionState(false)
    , m_shouldRecalcListItems(false)
    , m_suggestedIndex(-1)
{
    ScriptWrappable::init(this);
}

PassRefPtr<HTMLSelectElement> HTMLSelectElement::create(Document& document)
{
    return adoptRef(new HTMLSelectElement(document, 0));
}

PassRefPtr<HTMLSelectElement> HTMLSelectElement::create(Document& document, HTMLFormElement* form)
{
    return adoptRef(new HTMLSelectElement(document, form));
}

const AtomicString& HTMLSelectElement::formControlType() const
{
    DEFINE_STATIC_LOCAL(const AtomicString, selectMultiple, ("select-multiple", AtomicString::ConstructFromLiteral));
    DEFINE_STATIC_LOCAL(const AtomicString, selectOne, ("select-one", AtomicString::ConstructFromLiteral));
    return m_multiple ? selectMultiple : selectOne;
}

void HTMLSelectElement::optionSelectedByUser(int optionIndex, bool fireOnChangeNow, bool allowMultipleSelection)
{
    // User interaction such as mousedown events can cause list box select elements to send change events.
    // This produces that same behavior for changes triggered by other code running on behalf of the user.
    if (!usesMenuList()) {
        updateSelectedState(optionToListIndex(optionIndex), allowMultipleSelection, false);
        setNeedsValidityCheck();
        if (fireOnChangeNow)
            listBoxOnChange();
        return;
    }

    // Bail out if this index is already the selected one, to avoid running unnecessary JavaScript that can mess up
    // autofill when there is no actual change (see https://bugs.webkit.org/show_bug.cgi?id=35256 and <rdar://7467917>).
    // The selectOption function does not behave this way, possibly because other callers need a change event even
    // in cases where the selected option is not change.
    if (optionIndex == selectedIndex())
        return;

    selectOption(optionIndex, DeselectOtherOptions | (fireOnChangeNow ? DispatchInputAndChangeEvent : 0) | UserDriven);
}

bool HTMLSelectElement::hasPlaceholderLabelOption() const
{
    // The select element has no placeholder label option if it has an attribute "multiple" specified or a display size of non-1.
    //
    // The condition "size() > 1" is not compliant with the HTML5 spec as of Dec 3, 2010. "size() != 1" is correct.
    // Using "size() > 1" here because size() may be 0 in WebKit.
    // See the discussion at https://bugs.webkit.org/show_bug.cgi?id=43887
    //
    // "0 size()" happens when an attribute "size" is absent or an invalid size attribute is specified.
    // In this case, the display size should be assumed as the default.
    // The default display size is 1 for non-multiple select elements, and 4 for multiple select elements.
    //
    // Finally, if size() == 0 and non-multiple, the display size can be assumed as 1.
    if (multiple() || size() > 1)
        return false;

    int listIndex = optionToListIndex(0);
    ASSERT(listIndex >= 0);
    if (listIndex < 0)
        return false;
    return !listIndex && toHTMLOptionElement(listItems()[listIndex])->value().isEmpty();
}

String HTMLSelectElement::validationMessage() const
{
    if (!willValidate())
        return String();
    if (customError())
        return customValidationMessage();
    if (valueMissing())
        return locale().queryString(blink::WebLocalizedString::ValidationValueMissingForSelect);
    return String();
}

bool HTMLSelectElement::valueMissing() const
{
    if (!willValidate())
        return false;

    if (!isRequired())
        return false;

    int firstSelectionIndex = selectedIndex();

    // If a non-placeholer label option is selected (firstSelectionIndex > 0), it's not value-missing.
    return firstSelectionIndex < 0 || (!firstSelectionIndex && hasPlaceholderLabelOption());
}

void HTMLSelectElement::listBoxSelectItem(int listIndex, bool allowMultiplySelections, bool shift, bool fireOnChangeNow)
{
    if (!multiple())
        optionSelectedByUser(listToOptionIndex(listIndex), fireOnChangeNow, false);
    else {
        updateSelectedState(listIndex, allowMultiplySelections, shift);
        setNeedsValidityCheck();
        if (fireOnChangeNow)
            listBoxOnChange();
    }
}

bool HTMLSelectElement::usesMenuList() const
{
    if (RenderTheme::theme().delegatesMenuListRendering())
        return true;

    return !m_multiple && m_size <= 1;
}

int HTMLSelectElement::activeSelectionStartListIndex() const
{
    if (m_activeSelectionAnchorIndex >= 0)
        return m_activeSelectionAnchorIndex;
    return optionToListIndex(selectedIndex());
}

int HTMLSelectElement::activeSelectionEndListIndex() const
{
    if (m_activeSelectionEndIndex >= 0)
        return m_activeSelectionEndIndex;
    return lastSelectedListIndex();
}

void HTMLSelectElement::add(HTMLElement* element, HTMLElement* before, ExceptionState& exceptionState)
{
    // Make sure the element is ref'd and deref'd so we don't leak it.
    RefPtr<HTMLElement> protectNewChild(element);

    if (!element || !(isHTMLOptionElement(element) || isHTMLOptGroupElement(element) || isHTMLHRElement(element)))
        return;

    insertBefore(element, before, exceptionState);
    setNeedsValidityCheck();
}

void HTMLSelectElement::addBeforeOptionAtIndex(HTMLElement* element, int beforeIndex, ExceptionState& exceptionState)
{
    HTMLElement* beforeElement = toHTMLElement(options()->item(beforeIndex));
    add(element, beforeElement, exceptionState);
}

void HTMLSelectElement::remove(int optionIndex)
{
    int listIndex = optionToListIndex(optionIndex);
    if (listIndex < 0)
        return;

    listItems()[listIndex]->remove(IGNORE_EXCEPTION);
}

String HTMLSelectElement::value() const
{
    const Vector<HTMLElement*>& items = listItems();
    for (unsigned i = 0; i < items.size(); i++) {
        if (isHTMLOptionElement(items[i]) && toHTMLOptionElement(items[i])->selected())
            return toHTMLOptionElement(items[i])->value();
    }
    return "";
}

void HTMLSelectElement::setValue(const String &value, bool sendEvents)
{
    // We clear the previously selected option(s) when needed, to guarantee calling setSelectedIndex() only once.
    int optionIndex = 0;
    if (value.isNull()) {
        optionIndex = -1;
    } else {
        // Find the option with value() matching the given parameter and make it the current selection.
        const Vector<HTMLElement*>& items = listItems();
        for (unsigned i = 0; i < items.size(); i++) {
            if (isHTMLOptionElement(items[i])) {
                if (toHTMLOptionElement(items[i])->value() == value)
                    break;
                optionIndex++;
            }
        }
        if (optionIndex >= static_cast<int>(items.size()))
            optionIndex = -1;
    }

    int previousSelectedIndex = selectedIndex();
    setSelectedIndex(optionIndex);

    if (sendEvents && previousSelectedIndex != selectedIndex()) {
        if (usesMenuList())
            dispatchInputAndChangeEventForMenuList(false);
        else
            listBoxOnChange();
    }
}

String HTMLSelectElement::suggestedValue() const
{
    const Vector<HTMLElement*>& items = listItems();
    for (unsigned i = 0; i < items.size(); ++i) {
        if (isHTMLOptionElement(items[i]) && m_suggestedIndex >= 0) {
            if (i == static_cast<unsigned>(m_suggestedIndex))
                return toHTMLOptionElement(items[i])->value();
        }
    }
    return "";
}

void HTMLSelectElement::setSuggestedValue(const String& value)
{
    if (value.isNull()) {
        setSuggestedIndex(-1);
        return;
    }

    const Vector<HTMLElement*>& items = listItems();
    unsigned optionIndex = 0;
    for (unsigned i = 0; i < items.size(); ++i) {
        if (isHTMLOptionElement(items[i])) {
            if (toHTMLOptionElement(items[i])->value() == value) {
                setSuggestedIndex(optionIndex);
                return;
            }
            optionIndex++;
        }
    }

    setSuggestedIndex(-1);
}

bool HTMLSelectElement::isPresentationAttribute(const QualifiedName& name) const
{
    if (name == alignAttr) {
        // Don't map 'align' attribute. This matches what Firefox, Opera and IE do.
        // See http://bugs.webkit.org/show_bug.cgi?id=12072
        return false;
    }

    return HTMLFormControlElementWithState::isPresentationAttribute(name);
}

void HTMLSelectElement::parseAttribute(const QualifiedName& name, const AtomicString& value)
{
    if (name == sizeAttr) {
        int oldSize = m_size;
        // Set the attribute value to a number.
        // This is important since the style rules for this attribute can determine the appearance property.
        int size = value.toInt();
        AtomicString attrSize = AtomicString::number(size);
        if (attrSize != value) {
            // FIXME: This is horribly factored.
            if (Attribute* sizeAttribute = ensureUniqueElementData().getAttributeItem(sizeAttr))
                sizeAttribute->setValue(attrSize);
        }
        size = max(size, 1);

        // Ensure that we've determined selectedness of the items at least once prior to changing the size.
        if (oldSize != size)
            updateListItemSelectedStates();

        m_size = size;
        setNeedsValidityCheck();
        if (m_size != oldSize && inActiveDocument()) {
            lazyReattachIfAttached();
            setRecalcListItems();
        }
    } else if (name == multipleAttr)
        parseMultipleAttribute(value);
    else if (name == accesskeyAttr) {
        // FIXME: ignore for the moment.
        //
    } else if (name == disabledAttr) {
        HTMLFormControlElementWithState::parseAttribute(name, value);
        if (renderer() && renderer()->isMenuList()) {
            if (RenderMenuList* menuList = toRenderMenuList(renderer())) {
                if (menuList->popupIsVisible())
                    menuList->hidePopup();
            }
        }

    } else
        HTMLFormControlElementWithState::parseAttribute(name, value);
}

bool HTMLSelectElement::shouldShowFocusRingOnMouseFocus() const
{
    return true;
}

bool HTMLSelectElement::canSelectAll() const
{
    return !usesMenuList();
}

RenderObject* HTMLSelectElement::createRenderer(RenderStyle*)
{
    if (usesMenuList())
        return new RenderMenuList(this);
    return new RenderListBox(this);
}

PassRefPtr<HTMLCollection> HTMLSelectElement::selectedOptions()
{
    updateListItemSelectedStates();
    return ensureCachedHTMLCollection(SelectedOptions);
}

PassRefPtr<HTMLOptionsCollection> HTMLSelectElement::options()
{
    return static_cast<HTMLOptionsCollection*>(ensureCachedHTMLCollection(SelectOptions).get());
}

void HTMLSelectElement::updateListItemSelectedStates()
{
    if (!m_shouldRecalcListItems)
        return;
    recalcListItems();
    setNeedsValidityCheck();
}

void HTMLSelectElement::childrenChanged(bool changedByParser, Node* beforeChange, Node* afterChange, int childCountDelta)
{
    setRecalcListItems();
    setNeedsValidityCheck();
    m_lastOnChangeSelection.clear();

    HTMLFormControlElementWithState::childrenChanged(changedByParser, beforeChange, afterChange, childCountDelta);
}

void HTMLSelectElement::optionElementChildrenChanged()
{
    setRecalcListItems();
    setNeedsValidityCheck();

    if (renderer()) {
        if (AXObjectCache* cache = renderer()->document().existingAXObjectCache())
            cache->childrenChanged(this);
    }
}

void HTMLSelectElement::accessKeyAction(bool sendMouseEvents)
{
    focus();
    dispatchSimulatedClick(0, sendMouseEvents ? SendMouseUpDownEvents : SendNoEvents);
}

void HTMLSelectElement::setMultiple(bool multiple)
{
    bool oldMultiple = this->multiple();
    int oldSelectedIndex = selectedIndex();
    setAttribute(multipleAttr, multiple ? emptyAtom : nullAtom);

    // Restore selectedIndex after changing the multiple flag to preserve
    // selection as single-line and multi-line has different defaults.
    if (oldMultiple != this->multiple())
        setSelectedIndex(oldSelectedIndex);
}

void HTMLSelectElement::setSize(int size)
{
    setIntegralAttribute(sizeAttr, size);
}

Element* HTMLSelectElement::namedItem(const AtomicString& name)
{
    return options()->namedItem(name);
}

Element* HTMLSelectElement::item(unsigned index)
{
    return options()->item(index);
}

void HTMLSelectElement::setOption(unsigned index, HTMLOptionElement* option, ExceptionState& exceptionState)
{
    if (index > maxSelectItems - 1)
        index = maxSelectItems - 1;
    int diff = index - length();
    RefPtr<HTMLElement> before = nullptr;
    // Out of array bounds? First insert empty dummies.
    if (diff > 0) {
        setLength(index, exceptionState);
        // Replace an existing entry?
    } else if (diff < 0) {
        before = toHTMLElement(options()->item(index+1));
        remove(index);
    }
    // Finally add the new element.
    if (!exceptionState.hadException()) {
        add(option, before.get(), exceptionState);
        if (diff >= 0 && option->selected())
            optionSelectionStateChanged(option, true);
    }
}

void HTMLSelectElement::setLength(unsigned newLen, ExceptionState& exceptionState)
{
    if (newLen > maxSelectItems)
        newLen = maxSelectItems;
    int diff = length() - newLen;

    if (diff < 0) { // Add dummy elements.
        do {
            RefPtr<Element> option = document().createElement(optionTag, false);
            ASSERT(option);
            add(toHTMLElement(option), 0, exceptionState);
            if (exceptionState.hadException())
                break;
        } while (++diff);
    } else {
        const Vector<HTMLElement*>& items = listItems();

        // Removing children fires mutation events, which might mutate the DOM further, so we first copy out a list
        // of elements that we intend to remove then attempt to remove them one at a time.
        Vector<RefPtr<Element> > itemsToRemove;
        size_t optionIndex = 0;
        for (size_t i = 0; i < items.size(); ++i) {
            Element* item = items[i];
            if (isHTMLOptionElement(items[i]) && optionIndex++ >= newLen) {
                ASSERT(item->parentNode());
                itemsToRemove.append(item);
            }
        }

        for (size_t i = 0; i < itemsToRemove.size(); ++i) {
            Element* item = itemsToRemove[i].get();
            if (item->parentNode())
                item->parentNode()->removeChild(item, exceptionState);
        }
    }
    setNeedsValidityCheck();
}

bool HTMLSelectElement::isRequiredFormControl() const
{
    return isRequired();
}

// Returns the 1st valid item |skip| items from |listIndex| in direction |direction| if there is one.
// Otherwise, it returns the valid item closest to that boundary which is past |listIndex| if there is one.
// Otherwise, it returns |listIndex|.
// Valid means that it is enabled and an option element.
int HTMLSelectElement::nextValidIndex(int listIndex, SkipDirection direction, int skip) const
{
    ASSERT(direction == -1 || direction == 1);
    const Vector<HTMLElement*>& listItems = this->listItems();
    int lastGoodIndex = listIndex;
    int size = listItems.size();
    for (listIndex += direction; listIndex >= 0 && listIndex < size; listIndex += direction) {
        --skip;
        if (!listItems[listIndex]->isDisabledFormControl() && isHTMLOptionElement(*listItems[listIndex])) {
            lastGoodIndex = listIndex;
            if (skip <= 0)
                break;
        }
    }
    return lastGoodIndex;
}

int HTMLSelectElement::nextSelectableListIndex(int startIndex) const
{
    return nextValidIndex(startIndex, SkipForwards, 1);
}

int HTMLSelectElement::previousSelectableListIndex(int startIndex) const
{
    if (startIndex == -1)
        startIndex = listItems().size();
    return nextValidIndex(startIndex, SkipBackwards, 1);
}

int HTMLSelectElement::firstSelectableListIndex() const
{
    const Vector<HTMLElement*>& items = listItems();
    int index = nextValidIndex(items.size(), SkipBackwards, INT_MAX);
    if (static_cast<size_t>(index) == items.size())
        return -1;
    return index;
}

int HTMLSelectElement::lastSelectableListIndex() const
{
    return nextValidIndex(-1, SkipForwards, INT_MAX);
}

// Returns the index of the next valid item one page away from |startIndex| in direction |direction|.
int HTMLSelectElement::nextSelectableListIndexPageAway(int startIndex, SkipDirection direction) const
{
    const Vector<HTMLElement*>& items = listItems();
    // Can't use m_size because renderer forces a minimum size.
    int pageSize = 0;
    if (renderer()->isListBox())
        pageSize = toRenderListBox(renderer())->size() - 1; // -1 so we still show context.

    // One page away, but not outside valid bounds.
    // If there is a valid option item one page away, the index is chosen.
    // If there is no exact one page away valid option, returns startIndex or the most far index.
    int edgeIndex = (direction == SkipForwards) ? 0 : (items.size() - 1);
    int skipAmount = pageSize + ((direction == SkipForwards) ? startIndex : (edgeIndex - startIndex));
    return nextValidIndex(edgeIndex, direction, skipAmount);
}

void HTMLSelectElement::selectAll()
{
    ASSERT(!usesMenuList());
    if (!renderer() || !m_multiple)
        return;

    // Save the selection so it can be compared to the new selectAll selection
    // when dispatching change events.
    saveLastSelection();

    m_activeSelectionState = true;
    setActiveSelectionAnchorIndex(nextSelectableListIndex(-1));
    setActiveSelectionEndIndex(previousSelectableListIndex(-1));

    updateListBoxSelection(false);
    listBoxOnChange();
    setNeedsValidityCheck();
}

void HTMLSelectElement::saveLastSelection()
{
    if (usesMenuList()) {
        m_lastOnChangeIndex = selectedIndex();
        return;
    }

    m_lastOnChangeSelection.clear();
    const Vector<HTMLElement*>& items = listItems();
    for (unsigned i = 0; i < items.size(); ++i) {
        HTMLElement* element = items[i];
        m_lastOnChangeSelection.append(isHTMLOptionElement(*element) && toHTMLOptionElement(element)->selected());
    }
}

void HTMLSelectElement::setActiveSelectionAnchorIndex(int index)
{
    m_activeSelectionAnchorIndex = index;

    // Cache the selection state so we can restore the old selection as the new
    // selection pivots around this anchor index.
    m_cachedStateForActiveSelection.clear();

    const Vector<HTMLElement*>& items = listItems();
    for (unsigned i = 0; i < items.size(); ++i) {
        HTMLElement* element = items[i];
        m_cachedStateForActiveSelection.append(isHTMLOptionElement(*element) && toHTMLOptionElement(element)->selected());
    }
}

void HTMLSelectElement::setActiveSelectionEndIndex(int index)
{
    m_activeSelectionEndIndex = index;
}

void HTMLSelectElement::updateListBoxSelection(bool deselectOtherOptions)
{
    ASSERT(renderer() && (renderer()->isListBox() || m_multiple));
    ASSERT(!listItems().size() || m_activeSelectionAnchorIndex >= 0);

    unsigned start = min(m_activeSelectionAnchorIndex, m_activeSelectionEndIndex);
    unsigned end = max(m_activeSelectionAnchorIndex, m_activeSelectionEndIndex);

    const Vector<HTMLElement*>& items = listItems();
    for (unsigned i = 0; i < items.size(); ++i) {
        HTMLElement* element = items[i];
        if (!isHTMLOptionElement(*element) || toHTMLOptionElement(element)->isDisabledFormControl())
            continue;

        if (i >= start && i <= end)
            toHTMLOptionElement(element)->setSelectedState(m_activeSelectionState);
        else if (deselectOtherOptions || i >= m_cachedStateForActiveSelection.size())
            toHTMLOptionElement(element)->setSelectedState(false);
        else
            toHTMLOptionElement(element)->setSelectedState(m_cachedStateForActiveSelection[i]);
    }

    scrollToSelection();
    setNeedsValidityCheck();
    notifyFormStateChanged();
}

void HTMLSelectElement::listBoxOnChange()
{
    ASSERT(!usesMenuList() || m_multiple);

    const Vector<HTMLElement*>& items = listItems();

    // If the cached selection list is empty, or the size has changed, then fire
    // dispatchFormControlChangeEvent, and return early.
    // FIXME: Why? This looks unreasonable.
    if (m_lastOnChangeSelection.isEmpty() || m_lastOnChangeSelection.size() != items.size()) {
        dispatchFormControlChangeEvent();
        return;
    }

    // Update m_lastOnChangeSelection and fire dispatchFormControlChangeEvent.
    bool fireOnChange = false;
    for (unsigned i = 0; i < items.size(); ++i) {
        HTMLElement* element = items[i];
        bool selected = isHTMLOptionElement(*element) && toHTMLOptionElement(element)->selected();
        if (selected != m_lastOnChangeSelection[i])
            fireOnChange = true;
        m_lastOnChangeSelection[i] = selected;
    }

    if (fireOnChange) {
        RefPtr<HTMLSelectElement> protector(this);
        dispatchInputEvent();
        dispatchFormControlChangeEvent();
    }
}

void HTMLSelectElement::dispatchInputAndChangeEventForMenuList(bool requiresUserGesture)
{
    ASSERT(usesMenuList());

    int selected = selectedIndex();
    if (m_lastOnChangeIndex != selected && (!requiresUserGesture || m_isProcessingUserDrivenChange)) {
        m_lastOnChangeIndex = selected;
        m_isProcessingUserDrivenChange = false;
        RefPtr<HTMLSelectElement> protector(this);
        dispatchInputEvent();
        dispatchFormControlChangeEvent();
    }
}

void HTMLSelectElement::scrollToSelection()
{
    if (usesMenuList())
        return;

    if (RenderObject* renderer = this->renderer())
        toRenderListBox(renderer)->selectionChanged();
}

void HTMLSelectElement::setOptionsChangedOnRenderer()
{
    if (RenderObject* renderer = this->renderer()) {
        if (usesMenuList())
            toRenderMenuList(renderer)->setOptionsChanged(true);
        else
            toRenderListBox(renderer)->setOptionsChanged(true);
    }
}

const Vector<HTMLElement*>& HTMLSelectElement::listItems() const
{
    if (m_shouldRecalcListItems)
        recalcListItems();
    else {
#if !ASSERT_DISABLED
        Vector<HTMLElement*> items = m_listItems;
        recalcListItems(false);
        ASSERT(items == m_listItems);
#endif
    }

    return m_listItems;
}

void HTMLSelectElement::invalidateSelectedItems()
{
    if (HTMLCollection* collection = cachedHTMLCollection(SelectedOptions))
        collection->invalidateCache();
}

void HTMLSelectElement::setRecalcListItems()
{
    // FIXME: This function does a bunch of confusing things depending on if it
    // is in the document or not.

    m_shouldRecalcListItems = true;
    // Manual selection anchor is reset when manipulating the select programmatically.
    m_activeSelectionAnchorIndex = -1;
    setOptionsChangedOnRenderer();
    setNeedsStyleRecalc(SubtreeStyleChange);
    if (!inDocument()) {
        if (HTMLCollection* collection = cachedHTMLCollection(SelectOptions))
            collection->invalidateCache();
    }
    if (!inDocument())
        invalidateSelectedItems();

    if (renderer()) {
        if (AXObjectCache* cache = renderer()->document().existingAXObjectCache())
            cache->childrenChanged(this);
    }
}

void HTMLSelectElement::recalcListItems(bool updateSelectedStates) const
{
    m_listItems.clear();

    m_shouldRecalcListItems = false;

    HTMLOptionElement* foundSelected = 0;
    HTMLOptionElement* firstOption = 0;
    for (Element* currentElement = ElementTraversal::firstWithin(*this); currentElement; ) {
        if (!currentElement->isHTMLElement()) {
            currentElement = ElementTraversal::nextSkippingChildren(*currentElement, this);
            continue;
        }
        HTMLElement& current = toHTMLElement(*currentElement);

        // optgroup tags may not nest. However, both FireFox and IE will
        // flatten the tree automatically, so we follow suit.
        // (http://www.w3.org/TR/html401/interact/forms.html#h-17.6)
        if (isHTMLOptGroupElement(current)) {
            m_listItems.append(&current);
            if (Element* nextElement = ElementTraversal::firstWithin(current)) {
                currentElement = nextElement;
                continue;
            }
        }

        if (isHTMLOptionElement(current)) {
            m_listItems.append(&current);

            if (updateSelectedStates && !m_multiple) {
                HTMLOptionElement& option = toHTMLOptionElement(current);
                if (!firstOption)
                    firstOption = &option;
                if (option.selected()) {
                    if (foundSelected)
                        foundSelected->setSelectedState(false);
                    foundSelected = &option;
                } else if (m_size <= 1 && !foundSelected && !option.isDisabledFormControl()) {
                    foundSelected = &option;
                    foundSelected->setSelectedState(true);
                }
            }
        }

        if (isHTMLHRElement(current))
            m_listItems.append(&current);

        // In conforming HTML code, only <optgroup> and <option> will be found
        // within a <select>. We call NodeTraversal::nextSkippingChildren so that we only step
        // into those tags that we choose to. For web-compat, we should cope
        // with the case where odd tags like a <div> have been added but we
        // handle this because such tags have already been removed from the
        // <select>'s subtree at this point.
        currentElement = ElementTraversal::nextSkippingChildren(*currentElement, this);
    }

    if (!foundSelected && m_size <= 1 && firstOption && !firstOption->selected())
        firstOption->setSelectedState(true);
}

int HTMLSelectElement::selectedIndex() const
{
    unsigned index = 0;

    // Return the number of the first option selected.
    const Vector<HTMLElement*>& items = listItems();
    for (size_t i = 0; i < items.size(); ++i) {
        HTMLElement* element = items[i];
        if (isHTMLOptionElement(*element)) {
            if (toHTMLOptionElement(*element).selected())
                return index;
            ++index;
        }
    }

    return -1;
}

void HTMLSelectElement::setSelectedIndex(int index)
{
    selectOption(index, DeselectOtherOptions);
}

int HTMLSelectElement::suggestedIndex() const
{
    return m_suggestedIndex;
}

void HTMLSelectElement::setSuggestedIndex(int suggestedIndex)
{
    m_suggestedIndex = suggestedIndex;

    if (RenderObject* renderer = this->renderer())  {
        renderer->updateFromElement();
        if (renderer->isListBox())
            toRenderListBox(renderer)->scrollToRevealElementAtListIndex(suggestedIndex);
    }
}

void HTMLSelectElement::optionSelectionStateChanged(HTMLOptionElement* option, bool optionIsSelected)
{
    ASSERT(option->ownerSelectElement() == this);
    if (optionIsSelected)
        selectOption(option->index());
    else if (!usesMenuList() || multiple())
        selectOption(-1);
    else
        selectOption(nextSelectableListIndex(-1));
}

void HTMLSelectElement::selectOption(int optionIndex, SelectOptionFlags flags)
{
    bool shouldDeselect = !m_multiple || (flags & DeselectOtherOptions);

    const Vector<HTMLElement*>& items = listItems();
    int listIndex = optionToListIndex(optionIndex);

    HTMLElement* element = 0;
    if (listIndex >= 0) {
        element = items[listIndex];
        if (isHTMLOptionElement(*element)) {
            if (m_activeSelectionAnchorIndex < 0 || shouldDeselect)
                setActiveSelectionAnchorIndex(listIndex);
            if (m_activeSelectionEndIndex < 0 || shouldDeselect)
                setActiveSelectionEndIndex(listIndex);
            toHTMLOptionElement(*element).setSelectedState(true);
        }
    }

    if (shouldDeselect)
        deselectItemsWithoutValidation(element);

    // For the menu list case, this is what makes the selected element appear.
    if (RenderObject* renderer = this->renderer())
        renderer->updateFromElement();

    scrollToSelection();

    if (usesMenuList()) {
        m_isProcessingUserDrivenChange = flags & UserDriven;
        if (flags & DispatchInputAndChangeEvent)
            dispatchInputAndChangeEventForMenuList();
        if (RenderObject* renderer = this->renderer()) {
            if (usesMenuList())
                toRenderMenuList(renderer)->didSetSelectedIndex(listIndex);
            else if (renderer->isListBox())
                toRenderListBox(renderer)->selectionChanged();
        }
    }

    setNeedsValidityCheck();
    notifyFormStateChanged();
}

int HTMLSelectElement::optionToListIndex(int optionIndex) const
{
    const Vector<HTMLElement*>& items = listItems();
    int listSize = static_cast<int>(items.size());
    if (optionIndex < 0 || optionIndex >= listSize)
        return -1;

    int optionIndex2 = -1;
    for (int listIndex = 0; listIndex < listSize; ++listIndex) {
        if (isHTMLOptionElement(*items[listIndex])) {
            ++optionIndex2;
            if (optionIndex2 == optionIndex)
                return listIndex;
        }
    }

    return -1;
}

int HTMLSelectElement::listToOptionIndex(int listIndex) const
{
    const Vector<HTMLElement*>& items = listItems();
    if (listIndex < 0 || listIndex >= static_cast<int>(items.size()) || !isHTMLOptionElement(*items[listIndex]))
        return -1;

    // Actual index of option not counting OPTGROUP entries that may be in list.
    int optionIndex = 0;
    for (int i = 0; i < listIndex; ++i) {
        if (isHTMLOptionElement(*items[i]))
            ++optionIndex;
    }

    return optionIndex;
}

void HTMLSelectElement::dispatchFocusEvent(Element* oldFocusedElement, FocusType type)
{
    // Save the selection so it can be compared to the new selection when
    // dispatching change events during blur event dispatch.
    if (usesMenuList())
        saveLastSelection();
    HTMLFormControlElementWithState::dispatchFocusEvent(oldFocusedElement, type);
}

void HTMLSelectElement::dispatchBlurEvent(Element* newFocusedElement)
{
    // We only need to fire change events here for menu lists, because we fire
    // change events for list boxes whenever the selection change is actually made.
    // This matches other browsers' behavior.
    if (usesMenuList())
        dispatchInputAndChangeEventForMenuList();
    HTMLFormControlElementWithState::dispatchBlurEvent(newFocusedElement);
}

void HTMLSelectElement::deselectItemsWithoutValidation(HTMLElement* excludeElement)
{
    const Vector<HTMLElement*>& items = listItems();
    for (unsigned i = 0; i < items.size(); ++i) {
        HTMLElement* element = items[i];
        if (element != excludeElement && isHTMLOptionElement(*element))
            toHTMLOptionElement(element)->setSelectedState(false);
    }
}

FormControlState HTMLSelectElement::saveFormControlState() const
{
    const Vector<HTMLElement*>& items = listItems();
    size_t length = items.size();
    FormControlState state;
    for (unsigned i = 0; i < length; ++i) {
        if (!isHTMLOptionElement(*items[i]))
            continue;
        HTMLOptionElement* option = toHTMLOptionElement(items[i]);
        if (!option->selected())
            continue;
        state.append(option->value());
        if (!multiple())
            break;
    }
    return state;
}

size_t HTMLSelectElement::searchOptionsForValue(const String& value, size_t listIndexStart, size_t listIndexEnd) const
{
    const Vector<HTMLElement*>& items = listItems();
    size_t loopEndIndex = std::min(items.size(), listIndexEnd);
    for (size_t i = listIndexStart; i < loopEndIndex; ++i) {
        if (!isHTMLOptionElement(items[i]))
            continue;
        if (toHTMLOptionElement(items[i])->value() == value)
            return i;
    }
    return kNotFound;
}

void HTMLSelectElement::restoreFormControlState(const FormControlState& state)
{
    recalcListItems();

    const Vector<HTMLElement*>& items = listItems();
    size_t itemsSize = items.size();
    if (!itemsSize)
        return;

    for (size_t i = 0; i < itemsSize; ++i) {
        if (!isHTMLOptionElement(items[i]))
            continue;
        toHTMLOptionElement(items[i])->setSelectedState(false);
    }

    if (!multiple()) {
        size_t foundIndex = searchOptionsForValue(state[0], 0, itemsSize);
        if (foundIndex != kNotFound)
            toHTMLOptionElement(items[foundIndex])->setSelectedState(true);
    } else {
        size_t startIndex = 0;
        for (size_t i = 0; i < state.valueSize(); ++i) {
            const String& value = state[i];
            size_t foundIndex = searchOptionsForValue(value, startIndex, itemsSize);
            if (foundIndex == kNotFound)
                foundIndex = searchOptionsForValue(value, 0, startIndex);
            if (foundIndex == kNotFound)
                continue;
            toHTMLOptionElement(items[foundIndex])->setSelectedState(true);
            startIndex = foundIndex + 1;
        }
    }

    setOptionsChangedOnRenderer();
    setNeedsValidityCheck();
}

void HTMLSelectElement::parseMultipleAttribute(const AtomicString& value)
{
    bool oldUsesMenuList = usesMenuList();
    m_multiple = !value.isNull();
    setNeedsValidityCheck();
    if (oldUsesMenuList != usesMenuList())
        lazyReattachIfAttached();
}

bool HTMLSelectElement::appendFormData(FormDataList& list, bool)
{
    const AtomicString& name = this->name();
    if (name.isEmpty())
        return false;

    bool successful = false;
    const Vector<HTMLElement*>& items = listItems();

    for (unsigned i = 0; i < items.size(); ++i) {
        HTMLElement* element = items[i];
        if (isHTMLOptionElement(*element) && toHTMLOptionElement(*element).selected() && !toHTMLOptionElement(*element).isDisabledFormControl()) {
            list.appendData(name, toHTMLOptionElement(*element).value());
            successful = true;
        }
    }

    // It's possible that this is a menulist with multiple options and nothing
    // will be submitted (!successful). We won't send a unselected non-disabled
    // option as fallback. This behavior matches to other browsers.
    return successful;
}

void HTMLSelectElement::resetImpl()
{
    HTMLOptionElement* firstOption = 0;
    HTMLOptionElement* selectedOption = 0;

    const Vector<HTMLElement*>& items = listItems();
    for (unsigned i = 0; i < items.size(); ++i) {
        HTMLElement* element = items[i];
        if (!isHTMLOptionElement(*element))
            continue;

        if (items[i]->fastHasAttribute(selectedAttr)) {
            if (selectedOption && !m_multiple)
                selectedOption->setSelectedState(false);
            toHTMLOptionElement(element)->setSelectedState(true);
            selectedOption = toHTMLOptionElement(element);
        } else
            toHTMLOptionElement(element)->setSelectedState(false);

        if (!firstOption)
            firstOption = toHTMLOptionElement(element);
    }

    if (!selectedOption && firstOption && !m_multiple && m_size <= 1)
        firstOption->setSelectedState(true);

    setOptionsChangedOnRenderer();
    setNeedsStyleRecalc(SubtreeStyleChange);
    setNeedsValidityCheck();
}

#if !OS(WIN)
bool HTMLSelectElement::platformHandleKeydownEvent(KeyboardEvent* event)
{
    if (!RenderTheme::theme().popsMenuByArrowKeys())
        return false;

    if (!isSpatialNavigationEnabled(document().frame())) {
        if (event->keyIdentifier() == "Down" || event->keyIdentifier() == "Up") {
            focus();
            // Calling focus() may cause us to lose our renderer. Return true so
            // that our caller doesn't process the event further, but don't set
            // the event as handled.
            if (!renderer() || isDisabledFormControl())
                return true;

            // Save the selection so it can be compared to the new selection
            // when dispatching change events during selectOption, which
            // gets called from RenderMenuList::valueChanged, which gets called
            // after the user makes a selection from the menu.
            saveLastSelection();
            if (RenderMenuList* menuList = toRenderMenuList(renderer()))
                menuList->showPopup();
            event->setDefaultHandled();
        }
        return true;
    }

    return false;
}
#endif

void HTMLSelectElement::menuListDefaultEventHandler(Event* event)
{
    RenderTheme& renderTheme = RenderTheme::theme();

    if (event->type() == EventTypeNames::keydown) {
        if (!renderer() || !event->isKeyboardEvent())
            return;

        if (platformHandleKeydownEvent(toKeyboardEvent(event)))
            return;

        // When using spatial navigation, we want to be able to navigate away
        // from the select element when the user hits any of the arrow keys,
        // instead of changing the selection.
        if (isSpatialNavigationEnabled(document().frame())) {
            if (!m_activeSelectionState)
                return;
        }

        const String& keyIdentifier = toKeyboardEvent(event)->keyIdentifier();
        bool handled = true;
        const Vector<HTMLElement*>& listItems = this->listItems();
        int listIndex = optionToListIndex(selectedIndex());

        if (keyIdentifier == "Down" || keyIdentifier == "Right")
            listIndex = nextValidIndex(listIndex, SkipForwards, 1);
        else if (keyIdentifier == "Up" || keyIdentifier == "Left")
            listIndex = nextValidIndex(listIndex, SkipBackwards, 1);
        else if (keyIdentifier == "PageDown")
            listIndex = nextValidIndex(listIndex, SkipForwards, 3);
        else if (keyIdentifier == "PageUp")
            listIndex = nextValidIndex(listIndex, SkipBackwards, 3);
        else if (keyIdentifier == "Home")
            listIndex = nextValidIndex(-1, SkipForwards, 1);
        else if (keyIdentifier == "End")
            listIndex = nextValidIndex(listItems.size(), SkipBackwards, 1);
        else
            handled = false;

        if (handled && static_cast<size_t>(listIndex) < listItems.size())
            selectOption(listToOptionIndex(listIndex), DeselectOtherOptions | DispatchInputAndChangeEvent | UserDriven);

        if (handled)
            event->setDefaultHandled();
    }

    // Use key press event here since sending simulated mouse events
    // on key down blocks the proper sending of the key press event.
    if (event->type() == EventTypeNames::keypress) {
        if (!renderer() || !event->isKeyboardEvent())
            return;

        int keyCode = toKeyboardEvent(event)->keyCode();
        bool handled = false;

        if (keyCode == ' ' && isSpatialNavigationEnabled(document().frame())) {
            // Use space to toggle arrow key handling for selection change or spatial navigation.
            m_activeSelectionState = !m_activeSelectionState;
            event->setDefaultHandled();
            return;
        }

        if (renderTheme.popsMenuBySpaceOrReturn()) {
            if (keyCode == ' ' || keyCode == '\r') {
                focus();

                // Calling focus() may remove the renderer or change the
                // renderer type.
                if (!renderer() || !renderer()->isMenuList() || isDisabledFormControl())
                    return;

                // Save the selection so it can be compared to the new selection
                // when dispatching change events during selectOption, which
                // gets called from RenderMenuList::valueChanged, which gets called
                // after the user makes a selection from the menu.
                saveLastSelection();
                if (RenderMenuList* menuList = toRenderMenuList(renderer()))
                    menuList->showPopup();
                handled = true;
            }
        } else if (renderTheme.popsMenuByArrowKeys()) {
            if (keyCode == ' ') {
                focus();

                // Calling focus() may remove the renderer or change the
                // renderer type.
                if (!renderer() || !renderer()->isMenuList() || isDisabledFormControl())
                    return;

                // Save the selection so it can be compared to the new selection
                // when dispatching change events during selectOption, which
                // gets called from RenderMenuList::valueChanged, which gets called
                // after the user makes a selection from the menu.
                saveLastSelection();
                if (RenderMenuList* menuList = toRenderMenuList(renderer()))
                    menuList->showPopup();
                handled = true;
            } else if (keyCode == '\r') {
                if (form())
                    form()->submitImplicitly(event, false);
                dispatchInputAndChangeEventForMenuList();
                handled = true;
            }
        }

        if (handled)
            event->setDefaultHandled();
    }

    if (event->type() == EventTypeNames::mousedown && event->isMouseEvent() && toMouseEvent(event)->button() == LeftButton) {
        focus();
        if (renderer() && renderer()->isMenuList() && !isDisabledFormControl()) {
            if (RenderMenuList* menuList = toRenderMenuList(renderer())) {
                if (menuList->popupIsVisible())
                    menuList->hidePopup();
                else {
                    // Save the selection so it can be compared to the new
                    // selection when we call onChange during selectOption,
                    // which gets called from RenderMenuList::valueChanged,
                    // which gets called after the user makes a selection from
                    // the menu.
                    saveLastSelection();
                    menuList->showPopup();
                }
            }
        }
        event->setDefaultHandled();
    }

    if (event->type() == EventTypeNames::blur) {
        if (RenderMenuList* menuList = toRenderMenuList(renderer())) {
            if (menuList->popupIsVisible())
                menuList->hidePopup();
        }
    }
}

void HTMLSelectElement::updateSelectedState(int listIndex, bool multi, bool shift)
{
    ASSERT(listIndex >= 0);

    // Save the selection so it can be compared to the new selection when
    // dispatching change events during mouseup, or after autoscroll finishes.
    saveLastSelection();

    m_activeSelectionState = true;

    bool shiftSelect = m_multiple && shift;
    bool multiSelect = m_multiple && multi && !shift;

    HTMLElement* clickedElement = listItems()[listIndex];
    ASSERT(clickedElement);
    if (isHTMLOptionElement(*clickedElement)) {
        // Keep track of whether an active selection (like during drag
        // selection), should select or deselect.
        if (toHTMLOptionElement(*clickedElement).selected() && multiSelect)
            m_activeSelectionState = false;
        if (!m_activeSelectionState)
            toHTMLOptionElement(*clickedElement).setSelectedState(false);
    }

    // If we're not in any special multiple selection mode, then deselect all
    // other items, excluding the clicked option. If no option was clicked, then
    // this will deselect all items in the list.
    if (!shiftSelect && !multiSelect)
        deselectItemsWithoutValidation(clickedElement);

    // If the anchor hasn't been set, and we're doing a single selection or a
    // shift selection, then initialize the anchor to the first selected index.
    if (m_activeSelectionAnchorIndex < 0 && !multiSelect)
        setActiveSelectionAnchorIndex(selectedIndex());

    // Set the selection state of the clicked option.
    if (isHTMLOptionElement(*clickedElement) && !toHTMLOptionElement(*clickedElement).isDisabledFormControl())
        toHTMLOptionElement(*clickedElement).setSelectedState(true);

    // If there was no selectedIndex() for the previous initialization, or If
    // we're doing a single selection, or a multiple selection (using cmd or
    // ctrl), then initialize the anchor index to the listIndex that just got
    // clicked.
    if (m_activeSelectionAnchorIndex < 0 || !shiftSelect)
        setActiveSelectionAnchorIndex(listIndex);

    setActiveSelectionEndIndex(listIndex);
    updateListBoxSelection(!multiSelect);
}

void HTMLSelectElement::listBoxDefaultEventHandler(Event* event)
{
    const Vector<HTMLElement*>& listItems = this->listItems();
    bool dragSelection = false;
    if (event->type() == EventTypeNames::gesturetap && event->isGestureEvent()) {
        focus();
        // Calling focus() may cause us to lose our renderer or change the render type, in which case do not want to handle the event.
        if (!renderer() || !renderer()->isListBox())
            return;

        // Convert to coords relative to the list box if needed.
        GestureEvent& gestureEvent = toGestureEvent(*event);
        IntPoint localOffset = roundedIntPoint(renderer()->absoluteToLocal(gestureEvent.absoluteLocation(), UseTransforms));
        int listIndex = toRenderListBox(renderer())->listIndexAtOffset(toIntSize(localOffset));
        if (listIndex >= 0) {
            if (!isDisabledFormControl())
                updateSelectedState(listIndex, true, gestureEvent.shiftKey());
            event->setDefaultHandled();
        }
    } else if (event->type() == EventTypeNames::mousedown && event->isMouseEvent() && toMouseEvent(event)->button() == LeftButton) {
        focus();
        // Calling focus() may cause us to lose our renderer, in which case do not want to handle the event.
        if (!renderer())
            return;

        // Convert to coords relative to the list box if needed.
        MouseEvent* mouseEvent = toMouseEvent(event);
        IntPoint localOffset = roundedIntPoint(renderer()->absoluteToLocal(mouseEvent->absoluteLocation(), UseTransforms));
        int listIndex = toRenderListBox(renderer())->listIndexAtOffset(toIntSize(localOffset));
        if (listIndex >= 0) {
            if (!isDisabledFormControl()) {
#if OS(MACOSX)
                updateSelectedState(listIndex, mouseEvent->metaKey(), mouseEvent->shiftKey());
#else
                updateSelectedState(listIndex, mouseEvent->ctrlKey(), mouseEvent->shiftKey());
#endif
            }
            if (LocalFrame* frame = document().frame())
                frame->eventHandler().setMouseDownMayStartAutoscroll();

            event->setDefaultHandled();
        }
    } else if (event->type() == EventTypeNames::mousemove && event->isMouseEvent() && !toRenderBox(renderer())->canBeScrolledAndHasScrollableArea()) {
        MouseEvent* mouseEvent = toMouseEvent(event);
        if (mouseEvent->button() != LeftButton || !mouseEvent->buttonDown())
            return;

        IntPoint localOffset = roundedIntPoint(renderer()->absoluteToLocal(mouseEvent->absoluteLocation(), UseTransforms));
        int listIndex = toRenderListBox(renderer())->listIndexAtOffset(toIntSize(localOffset));
        if (listIndex >= 0) {
            if (!isDisabledFormControl()) {
                if (m_multiple) {
                    // Only extend selection if there is something selected.
                    if (m_activeSelectionAnchorIndex < 0)
                        return;

                    setActiveSelectionEndIndex(listIndex);
                    updateListBoxSelection(false);
                } else {
                    setActiveSelectionAnchorIndex(listIndex);
                    setActiveSelectionEndIndex(listIndex);
                    updateListBoxSelection(true);
                }
            }
            dragSelection = true;
        }
    } else if (event->type() == EventTypeNames::mouseup && event->isMouseEvent() && toMouseEvent(event)->button() == LeftButton && renderer() && !toRenderBox(renderer())->autoscrollInProgress()) {
        // We didn't start this click/drag on any options.
        if (m_lastOnChangeSelection.isEmpty())
            return;
        // This makes sure we fire dispatchFormControlChangeEvent for a single
        // click. For drag selection, onChange will fire when the autoscroll
        // timer stops.
        if (!dragSelection) {
            listBoxOnChange();
        }
    } else if (event->type() == EventTypeNames::keydown) {
        if (!event->isKeyboardEvent())
            return;
        const String& keyIdentifier = toKeyboardEvent(event)->keyIdentifier();

        bool handled = false;
        int endIndex = 0;
        if (m_activeSelectionEndIndex < 0) {
            // Initialize the end index
            if (keyIdentifier == "Down" || keyIdentifier == "PageDown") {
                int startIndex = lastSelectedListIndex();
                handled = true;
                if (keyIdentifier == "Down")
                    endIndex = nextSelectableListIndex(startIndex);
                else
                    endIndex = nextSelectableListIndexPageAway(startIndex, SkipForwards);
            } else if (keyIdentifier == "Up" || keyIdentifier == "PageUp") {
                int startIndex = optionToListIndex(selectedIndex());
                handled = true;
                if (keyIdentifier == "Up")
                    endIndex = previousSelectableListIndex(startIndex);
                else
                    endIndex = nextSelectableListIndexPageAway(startIndex, SkipBackwards);
            }
        } else {
            // Set the end index based on the current end index.
            if (keyIdentifier == "Down") {
                endIndex = nextSelectableListIndex(m_activeSelectionEndIndex);
                handled = true;
            } else if (keyIdentifier == "Up") {
                endIndex = previousSelectableListIndex(m_activeSelectionEndIndex);
                handled = true;
            } else if (keyIdentifier == "PageDown") {
                endIndex = nextSelectableListIndexPageAway(m_activeSelectionEndIndex, SkipForwards);
                handled = true;
            } else if (keyIdentifier == "PageUp") {
                endIndex = nextSelectableListIndexPageAway(m_activeSelectionEndIndex, SkipBackwards);
                handled = true;
            }
        }
        if (keyIdentifier == "Home") {
            endIndex = firstSelectableListIndex();
            handled = true;
        } else if (keyIdentifier == "End") {
            endIndex = lastSelectableListIndex();
            handled = true;
        }

        if (isSpatialNavigationEnabled(document().frame()))
            // Check if the selection moves to the boundary.
            if (keyIdentifier == "Left" || keyIdentifier == "Right" || ((keyIdentifier == "Down" || keyIdentifier == "Up") && endIndex == m_activeSelectionEndIndex))
                return;

        if (endIndex >= 0 && handled) {
            // Save the selection so it can be compared to the new selection
            // when dispatching change events immediately after making the new
            // selection.
            saveLastSelection();

            ASSERT_UNUSED(listItems, !listItems.size() || static_cast<size_t>(endIndex) < listItems.size());
            setActiveSelectionEndIndex(endIndex);

            bool selectNewItem = !m_multiple || toKeyboardEvent(event)->shiftKey() || !isSpatialNavigationEnabled(document().frame());
            if (selectNewItem)
                m_activeSelectionState = true;
            // If the anchor is unitialized, or if we're going to deselect all
            // other options, then set the anchor index equal to the end index.
            bool deselectOthers = !m_multiple || (!toKeyboardEvent(event)->shiftKey() && selectNewItem);
            if (m_activeSelectionAnchorIndex < 0 || deselectOthers) {
                if (deselectOthers)
                    deselectItemsWithoutValidation();
                setActiveSelectionAnchorIndex(m_activeSelectionEndIndex);
            }

            toRenderListBox(renderer())->scrollToRevealElementAtListIndex(endIndex);
            if (selectNewItem) {
                updateListBoxSelection(deselectOthers);
                listBoxOnChange();
            } else
                scrollToSelection();

            event->setDefaultHandled();
        }
    } else if (event->type() == EventTypeNames::keypress) {
        if (!event->isKeyboardEvent())
            return;
        int keyCode = toKeyboardEvent(event)->keyCode();

        if (keyCode == '\r') {
            if (form())
                form()->submitImplicitly(event, false);
            event->setDefaultHandled();
        } else if (m_multiple && keyCode == ' ' && isSpatialNavigationEnabled(document().frame())) {
            // Use space to toggle selection change.
            m_activeSelectionState = !m_activeSelectionState;
            updateSelectedState(listToOptionIndex(m_activeSelectionEndIndex), true /*multi*/, false /*shift*/);
            listBoxOnChange();
            event->setDefaultHandled();
        }
    }
}

void HTMLSelectElement::defaultEventHandler(Event* event)
{
    if (!renderer())
        return;

    if (isDisabledFormControl()) {
        HTMLFormControlElementWithState::defaultEventHandler(event);
        return;
    }

    if (usesMenuList())
        menuListDefaultEventHandler(event);
    else
        listBoxDefaultEventHandler(event);
    if (event->defaultHandled())
        return;

    if (event->type() == EventTypeNames::keypress && event->isKeyboardEvent()) {
        KeyboardEvent* keyboardEvent = toKeyboardEvent(event);
        if (!keyboardEvent->ctrlKey() && !keyboardEvent->altKey() && !keyboardEvent->metaKey() && isPrintableChar(keyboardEvent->charCode())) {
            typeAheadFind(keyboardEvent);
            event->setDefaultHandled();
            return;
        }
    }
    HTMLFormControlElementWithState::defaultEventHandler(event);
}

int HTMLSelectElement::lastSelectedListIndex() const
{
    const Vector<HTMLElement*>& items = listItems();
    for (size_t i = items.size(); i;) {
        HTMLElement* element = items[--i];
        if (isHTMLOptionElement(*element) && toHTMLOptionElement(element)->selected())
            return i;
    }
    return -1;
}

int HTMLSelectElement::indexOfSelectedOption() const
{
    return optionToListIndex(selectedIndex());
}

int HTMLSelectElement::optionCount() const
{
    return listItems().size();
}

String HTMLSelectElement::optionAtIndex(int index) const
{
    const Vector<HTMLElement*>& items = listItems();

    HTMLElement* element = items[index];
    if (!isHTMLOptionElement(*element) || toHTMLOptionElement(element)->isDisabledFormControl())
        return String();
    return toHTMLOptionElement(element)->textIndentedToRespectGroupLabel();
}

void HTMLSelectElement::typeAheadFind(KeyboardEvent* event)
{
    int index = m_typeAhead.handleEvent(event, TypeAhead::MatchPrefix | TypeAhead::CycleFirstChar);
    if (index < 0)
        return;
    selectOption(listToOptionIndex(index), DeselectOtherOptions | DispatchInputAndChangeEvent | UserDriven);
    if (!usesMenuList())
        listBoxOnChange();
}

Node::InsertionNotificationRequest HTMLSelectElement::insertedInto(ContainerNode* insertionPoint)
{
    // When the element is created during document parsing, it won't have any
    // items yet - but for innerHTML and related methods, this method is called
    // after the whole subtree is constructed.
    recalcListItems();
    HTMLFormControlElementWithState::insertedInto(insertionPoint);
    return InsertionDone;
}

void HTMLSelectElement::accessKeySetSelectedIndex(int index)
{
    // First bring into focus the list box.
    if (!focused())
        accessKeyAction(false);

    // If this index is already selected, unselect. otherwise update the selected index.
    const Vector<HTMLElement*>& items = listItems();
    int listIndex = optionToListIndex(index);
    if (listIndex >= 0) {
        HTMLElement* element = items[listIndex];
        if (isHTMLOptionElement(*element)) {
            if (toHTMLOptionElement(*element).selected())
                toHTMLOptionElement(*element).setSelectedState(false);
            else
                selectOption(index, DispatchInputAndChangeEvent | UserDriven);
        }
    }

    if (usesMenuList())
        dispatchInputAndChangeEventForMenuList();
    else
        listBoxOnChange();

    scrollToSelection();
}

unsigned HTMLSelectElement::length() const
{
    unsigned options = 0;

    const Vector<HTMLElement*>& items = listItems();
    for (unsigned i = 0; i < items.size(); ++i) {
        if (isHTMLOptionElement(*items[i]))
            ++options;
    }

    return options;
}

void HTMLSelectElement::finishParsingChildren()
{
    HTMLFormControlElementWithState::finishParsingChildren();
    updateListItemSelectedStates();
}

bool HTMLSelectElement::anonymousIndexedSetter(unsigned index, PassRefPtr<HTMLOptionElement> value, ExceptionState& exceptionState)
{
    if (!value) { // undefined or null
        remove(index);
        return true;
    }
    setOption(index, value.get(), exceptionState);
    return true;
}

bool HTMLSelectElement::isInteractiveContent() const
{
    return true;
}

bool HTMLSelectElement::supportsAutofocus() const
{
    return true;
}

} // namespace
/* [<][>][^][v][top][bottom][index][help] */
root/Source/core/html/HTMLSelectElement.cpp

DEFINITIONS
