CSSCustomPropertyValue.cpp

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#include "config.h"
#include "CSSCustomPropertyValue.h"

#include "CSSCalcValue.h"
#include "CSSFunctionValue.h"
#include "CSSMarkup.h"
#include "CSSParserIdioms.h"
#include "CSSTokenizer.h"
#include "ColorSerialization.h"
#include "ComputedStyleExtractor.h"
#include "RenderStyle.h"

namespace WebCore {

Ref<CSSCustomPropertyValue> CSSCustomPropertyValue::createEmpty(const AtomString& name)
{
    return adoptRef(*new CSSCustomPropertyValue(name, std::monostate { }));
}

Ref<CSSCustomPropertyValue> CSSCustomPropertyValue::createWithID(const AtomString& name, CSSValueID id)
{
    ASSERT(WebCore::isCSSWideKeyword(id) || id == CSSValueInvalid);
    return adoptRef(*new CSSCustomPropertyValue(name, { id }));
}

bool CSSCustomPropertyValue::equals(const CSSCustomPropertyValue& other) const
{
    if (m_name != other.m_name || m_value.index() != other.m_value.index())
        return false;
    return WTF::switchOn(m_value, [&](const std::monostate&) {
        return true;
    }, [&](const Ref<CSSVariableReferenceValue>& value) {
        return value.get() == std::get<Ref<CSSVariableReferenceValue>>(other.m_value).get();
    }, [&](const CSSValueID& value) {
        return value == std::get<CSSValueID>(other.m_value);
    }, [&](const Ref<CSSVariableData>& value) {
        return value.get() == std::get<Ref<CSSVariableData>>(other.m_value).get();
    }, [&](const SyntaxValue& value) {
        return value == std::get<SyntaxValue>(other.m_value);
    }, [&](const SyntaxValueList& value) {
        return value == std::get<SyntaxValueList>(other.m_value);
    });
}

String CSSCustomPropertyValue::customCSSText() const
{
    auto serializeSyntaxValue = [](const SyntaxValue& syntaxValue) -> String {
        return WTF::switchOn(syntaxValue, [&](const Length& value) {
            return CSSPrimitiveValue::create(value, RenderStyle::defaultStyle())->cssText();
        }, [&](const NumericSyntaxValue& value) {
            return CSSPrimitiveValue::create(value.value, value.unitType)->cssText();
        }, [&](const StyleColor& value) {
            return serializationForCSS(value);
        }, [&](const RefPtr<StyleImage>& value) {
            // FIXME: This is not right for gradients that use `currentcolor`. There should be a way preserve it.
            return value->computedStyleValue(RenderStyle::defaultStyle())->cssText();
        }, [&](const URL& value) {
            return serializeURL(value.string());
        }, [&](const String& value) {
            return value;
        }, [&](const TransformSyntaxValue& value) {
            auto cssValue = transformOperationAsCSSValue(*value.transform, RenderStyle::defaultStyle());
            if (!cssValue)
                return emptyString();
            return cssValue->cssText();
        });
    };

    if (m_stringValue.isNull()) {
        WTF::switchOn(m_value, [&](const std::monostate&) {
            m_stringValue = emptyString();
        }, [&](const Ref<CSSVariableReferenceValue>& value) {
            m_stringValue = value->cssText();
        }, [&](const CSSValueID& value) {
            m_stringValue = nameString(value);
        }, [&](const Ref<CSSVariableData>& value) {
            m_stringValue = value->tokenRange().serialize();
        }, [&](const SyntaxValue& syntaxValue) {
            m_stringValue = serializeSyntaxValue(syntaxValue);
        }, [&](const SyntaxValueList& syntaxValueList) {
            StringBuilder builder;
            auto separator = separatorCSSText(syntaxValueList.separator);
            for (auto& syntaxValue : syntaxValueList.values) {
                if (!builder.isEmpty())
                    builder.append(separator);
                builder.append(serializeSyntaxValue(syntaxValue));
            }
            m_stringValue = builder.toString();
        });
    }
    return m_stringValue;
}

Vector<CSSParserToken> CSSCustomPropertyValue::tokens() const
{
    Vector<CSSParserToken> result;
    WTF::switchOn(m_value, [&](const std::monostate&) {
        // Do nothing.
    }, [&](const Ref<CSSVariableReferenceValue>&) {
        ASSERT_NOT_REACHED();
    }, [&](const CSSValueID&) {
        // Do nothing.
    }, [&](const Ref<CSSVariableData>& value) {
        result.appendVector(value->tokens());
    }, [&](auto&) {
        CSSTokenizer tokenizer(customCSSText());
        auto tokenizerRange = tokenizer.tokenRange();
        while (!tokenizerRange.atEnd())
            result.append(tokenizerRange.consume());
    });
    return result;
}

bool CSSCustomPropertyValue::containsCSSWideKeyword() const
{
    return std::holds_alternative<CSSValueID>(m_value) && WebCore::isCSSWideKeyword(std::get<CSSValueID>(m_value));
}

Ref<const CSSVariableData> CSSCustomPropertyValue::asVariableData() const
{
    return WTF::switchOn(m_value, [&](const Ref<CSSVariableData>& value) -> Ref<const CSSVariableData> {
        return value.get();
    }, [&](const Ref<CSSVariableReferenceValue>& value) -> Ref<const CSSVariableData> {
        return value->data();
    }, [&](auto&) -> Ref<const CSSVariableData> {
        return CSSVariableData::create(tokens());
    });
}

bool CSSCustomPropertyValue::isCurrentColor() const
{
    // FIXME: it's surprising that setting a custom property to "currentcolor"
    // results in m_value being a CSSVariableReferenceValue rather than a
    // CSSValueID set to CSSValueCurrentcolor or a StyleValue.
    return std::holds_alternative<Ref<CSSVariableReferenceValue>>(m_value) && std::get<Ref<CSSVariableReferenceValue>>(m_value)->customCSSText() == "currentcolor"_s;
}

}