Source/WebCore/html/HTMLTextAreaElement.cpp

/*
 * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
 *           (C) 1999 Antti Koivisto (koivisto@kde.org)
 *           (C) 2001 Dirk Mueller (mueller@kde.org)
 * Copyright (C) 2004-2022 Apple Inc. All rights reserved.
 *           (C) 2006 Alexey Proskuryakov (ap@nypop.com)
 * Copyright (C) 2007 Samuel Weinig (sam@webkit.org)
 *
 * 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 "HTMLTextAreaElement.h"

#include "AXObjectCache.h"
#include "BeforeTextInsertedEvent.h"
#include "CSSValueKeywords.h"
#include "Chrome.h"
#include "ChromeClient.h"
#include "DOMFormData.h"
#include "Document.h"
#include "Editor.h"
#include "ElementInlines.h"
#include "Event.h"
#include "EventNames.h"
#include "FormController.h"
#include "FrameSelection.h"
#include "HTMLNames.h"
#include "HTMLParserIdioms.h"
#include "LocalFrame.h"
#include "LocalizedStrings.h"
#include "NodeName.h"
#include "RenderObjectInlines.h"
#include "RenderTextControlMultiLine.h"
#include "ShadowRoot.h"
#include "Text.h"
#include "TextControlInnerElements.h"
#include "TextIterator.h"
#include "TextNodeTraversal.h"
#include <wtf/Ref.h>
#include <wtf/StdLibExtras.h>
#include <wtf/TZoneMallocInlines.h>

namespace WebCore {

WTF_MAKE_TZONE_OR_ISO_ALLOCATED_IMPL(HTMLTextAreaElement);

using namespace HTMLNames;

static inline unsigned computeLengthForAPIValue(StringView text)
{
    unsigned length = text.length();
    unsigned crlfCount = 0;
    for (unsigned i = 0; i < length; ++i) {
        if (text[i] == '\r' && i + 1 < length && text[i + 1] == '\n')
            crlfCount++;
    }
    return text.length() - crlfCount;
}

HTMLTextAreaElement::HTMLTextAreaElement(Document& document, HTMLFormElement* form)
    : HTMLTextFormControlElement(textareaTag, document, form)
{
    setFormControlValueMatchesRenderer(true);
}

Ref<HTMLTextAreaElement> HTMLTextAreaElement::create(const QualifiedName& tagName, Document& document, HTMLFormElement* form)
{
    ASSERT_UNUSED(tagName, tagName == textareaTag);
    auto textArea = adoptRef(*new HTMLTextAreaElement(document, form));
    textArea->ensureUserAgentShadowRoot();
    return textArea;
}

Ref<HTMLTextAreaElement> HTMLTextAreaElement::create(Document& document)
{
    return create(textareaTag, document, nullptr);
}

void HTMLTextAreaElement::didAddUserAgentShadowRoot(ShadowRoot& root)
{
    root.appendChild(TextControlInnerTextElement::create(document(), isInnerTextElementEditable()));
}

const AtomString& HTMLTextAreaElement::formControlType() const
{
    return textareaTag->localName();
}

FormControlState HTMLTextAreaElement::saveFormControlState() const
{
    return m_isDirty ? FormControlState { { AtomString { value() } } } : FormControlState { };
}

void HTMLTextAreaElement::restoreFormControlState(const FormControlState& state)
{
    setValue(state[0]);
}

void HTMLTextAreaElement::childrenChanged(const ChildChange& change)
{
    HTMLElement::childrenChanged(change);
    setLastChangeWasNotUserEdit();
    if (m_isDirty)
        setInnerTextValue(String { value() });
    else
        setNonDirtyValue(defaultValue(), TextControlSetValueSelection::Clamp);
}

bool HTMLTextAreaElement::hasPresentationalHintsForAttribute(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=7075
        return false;
    }
    if (name == wrapAttr)
        return true;
    return HTMLTextFormControlElement::hasPresentationalHintsForAttribute(name);
}

void HTMLTextAreaElement::collectPresentationalHintsForAttribute(const QualifiedName& name, const AtomString& value, MutableStyleProperties& style)
{
    if (name == wrapAttr) {
        if (m_wrap != NoWrap) {
            addPropertyToPresentationalHintStyle(style, CSSPropertyWhiteSpaceCollapse, CSSValuePreserve);
            addPropertyToPresentationalHintStyle(style, CSSPropertyTextWrapMode, CSSValueWrap);
            addPropertyToPresentationalHintStyle(style, CSSPropertyOverflowWrap, CSSValueBreakWord);
        } else {
            addPropertyToPresentationalHintStyle(style, CSSPropertyWhiteSpaceCollapse, CSSValuePreserve);
            addPropertyToPresentationalHintStyle(style, CSSPropertyTextWrapMode, CSSValueNowrap);
            addPropertyToPresentationalHintStyle(style, CSSPropertyOverflowWrap, CSSValueNormal);
        }
    } else
        HTMLTextFormControlElement::collectPresentationalHintsForAttribute(name, value, style);
}

void HTMLTextAreaElement::attributeChanged(const QualifiedName& name, const AtomString& oldValue, const AtomString& newValue, AttributeModificationReason attributeModificationReason)
{
    HTMLTextFormControlElement::attributeChanged(name, oldValue, newValue, attributeModificationReason);

    switch (name.nodeName()) {
    case AttributeNames::rowsAttr: {
        unsigned rows = limitToOnlyHTMLNonNegativeNumbersGreaterThanZero(newValue, defaultRows);
        if (m_rows != rows) {
            m_rows = rows;
            if (renderer())
                renderer()->setNeedsLayoutAndPreferredWidthsUpdate();
        }
        break;
    }
    case AttributeNames::colsAttr: {
        unsigned cols = limitToOnlyHTMLNonNegativeNumbersGreaterThanZero(newValue, defaultCols);
        if (m_cols != cols) {
            m_cols = cols;
            if (renderer())
                renderer()->setNeedsLayoutAndPreferredWidthsUpdate();
        }
        break;
    }
    case AttributeNames::wrapAttr: {
        // The virtual/physical values were a Netscape extension of HTML 3.0, now deprecated.
        // The soft/hard /off values are a recommendation for HTML 4 extension by IE and NS 4.
        WrapMethod wrap;
        if (equalLettersIgnoringASCIICase(newValue, "physical"_s) || equalLettersIgnoringASCIICase(newValue, "hard"_s) || equalLettersIgnoringASCIICase(newValue, "on"_s))
            wrap = HardWrap;
        else if (equalLettersIgnoringASCIICase(newValue, "off"_s))
            wrap = NoWrap;
        else
            wrap = SoftWrap;
        if (wrap != m_wrap) {
            m_wrap = wrap;
            if (renderer())
                renderer()->setNeedsLayoutAndPreferredWidthsUpdate();
        }
        break;
    }
    case AttributeNames::maxlengthAttr:
        internalSetMaxLength(parseHTMLNonNegativeInteger(newValue).value_or(-1));
        updateValidity();
        break;
    case AttributeNames::minlengthAttr:
        internalSetMinLength(parseHTMLNonNegativeInteger(newValue).value_or(-1));
        updateValidity();
        break;
    default:
        break;
    }
}

RenderPtr<RenderElement> HTMLTextAreaElement::createElementRenderer(RenderStyle&& style, const RenderTreePosition&)
{
    return createRenderer<RenderTextControlMultiLine>(*this, WTFMove(style));
}

bool HTMLTextAreaElement::appendFormData(DOMFormData& formData)
{
    if (name().isEmpty())
        return false;

    Ref protectedThis(*this);
    document().updateLayout();

    formData.append(name(), m_wrap == HardWrap ? valueWithHardLineBreaks() : value().get());
    if (auto& dirname = attributeWithoutSynchronization(dirnameAttr); !dirname.isNull())
        formData.append(dirname, directionForFormData());
    return true;    
}

void HTMLTextAreaElement::reset()
{
    setInteractedWithSinceLastFormSubmitEvent(false);
    setNonDirtyValue(defaultValue(), TextControlSetValueSelection::SetSelectionToEnd);
}

void HTMLTextAreaElement::updateFocusAppearance(SelectionRestorationMode restorationMode, SelectionRevealMode revealMode)
{
    if (restorationMode == SelectionRestorationMode::RestoreOrSelectAll && hasCachedSelection())
        restoreCachedSelection(revealMode, Element::defaultFocusTextStateChangeIntent());
    else {
        // If this is the first focus, set a caret at the beginning of the text.  
        // This matches some browsers' behavior; see bug 11746 Comment #15.
        // http://bugs.webkit.org/show_bug.cgi?id=11746#c15
        setSelectionRange(0, 0, SelectionHasNoDirection, revealMode, Element::defaultFocusTextStateChangeIntent());
    }
}

void HTMLTextAreaElement::defaultEventHandler(Event& event)
{
    if (renderer()) {
        if (event.isMouseEvent() || event.type() == eventNames().blurEvent)
            forwardEvent(event);
        else if (auto* insertedEvent = dynamicDowncast<BeforeTextInsertedEvent>(event))
            handleBeforeTextInsertedEvent(*insertedEvent);
    }

    HTMLTextFormControlElement::defaultEventHandler(event);
}

void HTMLTextAreaElement::subtreeHasChanged()
{
    setFormControlValueMatchesRenderer(false);
    updateValidity();
    updatePlaceholderVisibility();

    if (!focused())
        return;

    setChangedSinceLastFormControlChangeEvent(true);

    if (RefPtr frame = document().frame())
        frame->editor().textDidChangeInTextArea(*this);
    // When typing in a textarea, childrenChanged is not called, so we need to force the directionality check.
    if (selfOrPrecedingNodesAffectDirAuto())
        updateEffectiveTextDirection();
}

void HTMLTextAreaElement::handleBeforeTextInsertedEvent(BeforeTextInsertedEvent& event) const
{
    ASSERT(renderer());
    int signedMaxLength = maxLength();
    if (signedMaxLength < 0)
        return;
    unsigned unsignedMaxLength = static_cast<unsigned>(signedMaxLength);

    const String& currentValue = innerTextValue();
    unsigned currentLength = computeLengthForAPIValue(currentValue);
    if (currentLength + computeLengthForAPIValue(event.text()) < unsignedMaxLength)
        return;

    // selectionLength represents the selection length of this text field to be
    // removed by this insertion.
    // If the text field has no focus, we don't need to take account of the
    // selection length. The selection is the source of text drag-and-drop in
    // that case, and nothing in the text field will be removed.
    auto selectionRange = focused() ? document().frame()->selection().selection().toNormalizedRange() : std::nullopt;
    unsigned selectionLength = selectionRange ? computeLengthForAPIValue(plainText(*selectionRange)) : 0;
    ASSERT(currentLength >= selectionLength);
    unsigned baseLength = currentLength - selectionLength;
    unsigned appendableLength = unsignedMaxLength > baseLength ? unsignedMaxLength - baseLength : 0;
    event.setText(sanitizeUserInputValue(event.text(), appendableLength));
}

String HTMLTextAreaElement::sanitizeUserInputValue(const String& proposedValue, unsigned maxLength)
{
    unsigned submissionLength = 0;
    unsigned i = 0;
    for (; i < proposedValue.length(); ++i) {
        if (proposedValue[i] == '\r' && i + 1 < proposedValue.length() && proposedValue[i + 1] == '\n')
            continue;
        ++submissionLength;
        if (submissionLength == maxLength) {
            ++i;
            break;
        }
        if (submissionLength > maxLength)
            break;
    }
    if (i > 0 && U16_IS_LEAD(proposedValue[i - 1]))
        --i;
    return proposedValue.left(i);
}

RefPtr<TextControlInnerTextElement> HTMLTextAreaElement::innerTextElement() const
{
    RefPtr root = userAgentShadowRoot();
    return root ? downcast<TextControlInnerTextElement>(root->firstChild()) : nullptr;
}

RefPtr<TextControlInnerTextElement> HTMLTextAreaElement::innerTextElementCreatingShadowSubtreeIfNeeded()
{
    return innerTextElement();
}

void HTMLTextAreaElement::updateValue() const
{
    if (formControlValueMatchesRenderer())
        return;

    ASSERT(renderer());
    m_value = innerTextValue();
    const_cast<HTMLTextAreaElement*>(this)->setFormControlValueMatchesRenderer(true);
    m_isDirty = true;
    m_wasModifiedByUser = true;
    const_cast<HTMLTextAreaElement*>(this)->updatePlaceholderVisibility();
}

ValueOrReference<String> HTMLTextAreaElement::value() const
{
    if (protectedDocument()->requiresScriptTrackingPrivacyProtection(ScriptTrackingPrivacyCategory::FormControls))
        return emptyString();
    updateValue();
    return m_value;
}

ExceptionOr<void> HTMLTextAreaElement::setValue(const String& value, TextFieldEventBehavior eventBehavior, TextControlSetValueSelection selection)
{
    setValueCommon(value, eventBehavior, selection);
    m_isDirty = true;
    updateValidity();
    return { };
}

void HTMLTextAreaElement::setNonDirtyValue(const String& value, TextControlSetValueSelection selection)
{
    setValueCommon(value, TextFieldEventBehavior::DispatchNoEvent, selection);
    m_isDirty = false;
    updateValidity();
}

void HTMLTextAreaElement::setValueCommon(const String& newValue, TextFieldEventBehavior eventBehavior, TextControlSetValueSelection selection)
{
    m_wasModifiedByUser = false;
    // Code elsewhere normalizes line endings added by the user via the keyboard or pasting.
    // We normalize line endings coming from JavaScript here.
    auto normalizedValue = newValue.isNull() ? emptyString() : makeStringBySimplifyingNewLines(newValue);

    // Return early because we don't want to move the caret or trigger other side effects
    // when the value isn't changing. This matches Firefox behavior, at least.
    if (normalizedValue == value())
        return;

    bool valueWasEmpty = m_value.isEmpty();
    bool shouldClamp = selection == TextControlSetValueSelection::Clamp;
    auto selectionStartValue = shouldClamp ? computeSelectionStart() : 0;
    auto selectionEndValue = shouldClamp ? computeSelectionEnd() : 0;

    m_value = normalizedValue;
    setInnerTextValue(String { m_value });
    setLastChangeWasNotUserEdit();
    updatePlaceholderVisibility();
    invalidateStyleForSubtree();
    if (selfOrPrecedingNodesAffectDirAuto())
        updateEffectiveTextDirection();
    setFormControlValueMatchesRenderer(true);

    auto endOfString = m_value.length();
    if (selection == TextControlSetValueSelection::SetSelectionToEnd) {
        if (document().focusedElement() == this)
            setSelectionRange(endOfString, endOfString);
        else {
            // We don't change text selection here but need to update caret to
            // the end of the text value except for initialize.
            cacheSelection(endOfString, endOfString, SelectionHasNoDirection);
        }
    } else if (shouldClamp)
        cacheSelection(std::min(endOfString, selectionStartValue), std::min(endOfString, selectionEndValue), SelectionHasNoDirection);

    setTextAsOfLastFormControlChangeEvent(String(normalizedValue));

    if (CheckedPtr cache = document().existingAXObjectCache())
        cache->valueChanged(*this);

    if (eventBehavior == DispatchNoEvent && !valueWasEmpty && normalizedValue.isEmpty()) {
        if (RefPtr page = document().page())
            page->chrome().client().didProgrammaticallyClearTextFormControl(*this);
    }
}

String HTMLTextAreaElement::defaultValue() const
{
    return TextNodeTraversal::childTextContent(*this);
}

void HTMLTextAreaElement::setDefaultValue(String&& defaultValue)
{
    setTextContent(WTFMove(defaultValue));
}

String HTMLTextAreaElement::validationMessage() const
{
    if (!willValidate())
        return String();

    if (customError())
        return customValidationMessage();

    if (valueMissing())
        return validationMessageValueMissingText();

    if (tooShort())
        return validationMessageTooShortText(value()->length(), minLength());

    if (tooLong())
        return validationMessageTooLongText(value()->length(), maxLength());

    return String();
}

void HTMLTextAreaElement::setSelectionRangeForBindings(unsigned start, unsigned end, const String& direction)
{
    setSelectionRange(start, end, direction, AXTextStateChangeIntent(), ForBindings::Yes);
}

bool HTMLTextAreaElement::valueMissing() const
{
    return valueMissing({ });
}

bool HTMLTextAreaElement::tooShort() const
{
    return tooShort({ }, CheckDirtyFlag);
}

bool HTMLTextAreaElement::tooLong() const
{
    return tooLong({ }, CheckDirtyFlag);
}

bool HTMLTextAreaElement::valueMissing(StringView value) const
{
    if (!(isRequired() && isMutable()))
        return false;
    if (value.isNull())
        return this->value()->isEmpty();
    return value.isEmpty();
}

bool HTMLTextAreaElement::isValidValue(StringView candidate) const
{
    return !valueMissing(candidate) && !tooShort(candidate, IgnoreDirtyFlag) && !tooLong(candidate, IgnoreDirtyFlag);
}

bool HTMLTextAreaElement::tooShort(StringView value, NeedsToCheckDirtyFlag check) const
{
    // Return false for the default value or value set by script even if it is
    // shorter than minLength.
    if (check == CheckDirtyFlag && !m_wasModifiedByUser)
        return false;

    int min = minLength();
    if (min <= 0)
        return false;

    // The empty string is excluded from tooShort validation.
    unsigned length = value.isNull() ? this->value()->length() : computeLengthForAPIValue(value);
    return length > 0 && length < static_cast<unsigned>(min);
}

bool HTMLTextAreaElement::tooLong(StringView value, NeedsToCheckDirtyFlag check) const
{
    // Return false for the default value or value set by script even if it is
    // longer than maxLength.
    if (check == CheckDirtyFlag && !m_wasModifiedByUser)
        return false;

    int max = maxLength();
    if (max < 0)
        return false;

    unsigned length = value.isNull() ? this->value()->length() : computeLengthForAPIValue(value);
    return length > static_cast<unsigned>(max);
}

bool HTMLTextAreaElement::accessKeyAction(bool)
{
    focus();
    return false;
}

void HTMLTextAreaElement::setCols(unsigned cols)
{
    setUnsignedIntegralAttribute(colsAttr, limitToOnlyHTMLNonNegativeNumbersGreaterThanZero(cols, defaultCols));
}

void HTMLTextAreaElement::setRows(unsigned rows)
{
    setUnsignedIntegralAttribute(rowsAttr, limitToOnlyHTMLNonNegativeNumbersGreaterThanZero(rows, defaultRows));
}

void HTMLTextAreaElement::updatePlaceholderText()
{
    auto& placeholderText = attributeWithoutSynchronization(placeholderAttr);
    if (placeholderText.isEmpty()) {
        if (RefPtr placeholder = m_placeholder) {
            protectedUserAgentShadowRoot()->removeChild(*placeholder);
            m_placeholder = nullptr;
        }
        return;
    }
    if (!m_placeholder) {
        m_placeholder = TextControlPlaceholderElement::create(document());
        protectedUserAgentShadowRoot()->insertBefore(*protectedPlaceholderElement(), innerTextElement()->protectedNextSibling());
    }
    protectedPlaceholderElement()->setInnerText(String { placeholderText });
}

RefPtr<HTMLElement> HTMLTextAreaElement::protectedPlaceholderElement() const
{
    return m_placeholder;
}

RenderStyle HTMLTextAreaElement::createInnerTextStyle(const RenderStyle& style)
{
    auto textBlockStyle = RenderStyle::create();
    textBlockStyle.inheritFrom(style);
    adjustInnerTextStyle(style, textBlockStyle);
    textBlockStyle.setDisplay(DisplayType::Block);
    return textBlockStyle;
}

void HTMLTextAreaElement::copyNonAttributePropertiesFromElement(const Element& source)
{
    auto& sourceElement = downcast<HTMLTextAreaElement>(source);

    setValueCommon(sourceElement.value(), DispatchNoEvent, TextControlSetValueSelection::DoNotSet);
    m_isDirty = sourceElement.m_isDirty;
    HTMLTextFormControlElement::copyNonAttributePropertiesFromElement(source);

    updateValidity();
}

} // namespace WebCore