Source/WebCore/css/StyleColor.cpp

/*
 * Copyright (C) 2015 Google Inc. All rights reserved.
 * Copyright (C) 2016 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *     * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above
 * copyright notice, this list of conditions and the following disclaimer
 * in the documentation and/or other materials provided with the
 * distribution.
 *     * Neither the name of Google Inc. nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "config.h"
#include "StyleColor.h"

#include "HashTools.h"
#include "RenderTheme.h"

namespace WebCore {

Color StyleColor::colorFromKeyword(CSSValueID keyword, OptionSet<StyleColorOptions> options)
{
    if (const char* valueName = getValueName(keyword)) {
        if (const NamedColor* namedColor = findColor(valueName, strlen(valueName)))
            return asSRGBA(PackedColor::ARGB { namedColor->ARGBValue });
    }

    ASSERT(!isAbsoluteColorKeyword(keyword));
    return RenderTheme::singleton().systemColor(keyword, options);
}

static bool isVGAPaletteColor(CSSValueID id)
{
    // https://drafts.csswg.org/css-color-4/#named-colors
    // "16 of CSS’s named colors come from the VGA palette originally, and were then adopted into HTML"
    return (id >= CSSValueAqua && id <= CSSValueYellow) || id == CSSValueGrey;
}

static bool isNonVGANamedColor(CSSValueID id)
{
    // https://drafts.csswg.org/css-color-4/#named-colors
    return id >= CSSValueAliceblue && id <= CSSValueYellowgreen;
}

bool StyleColor::isAbsoluteColorKeyword(CSSValueID id)
{
    // https://drafts.csswg.org/css-color-4/#typedef-absolute-color
    return isVGAPaletteColor(id) || isNonVGANamedColor(id) || id == CSSValueAlpha || id == CSSValueTransparent;
}

bool StyleColor::isSystemColorKeyword(CSSValueID id)
{
    // https://drafts.csswg.org/css-color-4/#css-system-colors
    // https://drafts.csswg.org/css-color-4/#deprecated-system-colors
    return (id >= CSSValueWebkitLink && id <= CSSValueWebkitFocusRingColor) || id == CSSValueWebkitText || id == CSSValueMenu || id == CSSValueText;
}

bool StyleColor::isColorKeyword(CSSValueID id, OptionSet<CSSColorType> allowedColorTypes)
{
    return (allowedColorTypes.contains(CSSColorType::Absolute) && isAbsoluteColorKeyword(id))
        || (allowedColorTypes.contains(CSSColorType::Current) && id == CSSValueCurrentcolor)
        || (allowedColorTypes.contains(CSSColorType::System) && isSystemColorKeyword(id));
}

} // namespace WebCore