ladybird/Libraries/LibWeb/CSS/StyleValues/CSSRGB.cpp
2025-07-16 13:05:33 +01:00

111 lines
4 KiB
C++

/*
* Copyright (c) 2024, Sam Atkins <sam@ladybird.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include "CSSRGB.h"
#include <AK/TypeCasts.h>
#include <LibWeb/CSS/Serialize.h>
#include <LibWeb/CSS/StyleValues/CSSKeywordValue.h>
#include <LibWeb/CSS/StyleValues/CalculatedStyleValue.h>
#include <LibWeb/CSS/StyleValues/NumberStyleValue.h>
#include <LibWeb/CSS/StyleValues/PercentageStyleValue.h>
namespace Web::CSS {
Optional<Color> CSSRGB::to_color(Optional<Layout::NodeWithStyle const&>, CalculationResolutionContext const& resolution_context) const
{
auto resolve_rgb_to_u8 = [&resolution_context](CSSStyleValue const& style_value) -> Optional<u8> {
// <number> | <percentage> | none
auto normalized = [](double number) {
if (isnan(number))
number = 0;
return llround(clamp(number, 0.0, 255.0));
};
if (style_value.is_number())
return normalized(style_value.as_number().number());
if (style_value.is_percentage())
return normalized(style_value.as_percentage().value() * 255 / 100);
if (style_value.is_calculated()) {
auto const& calculated = style_value.as_calculated();
if (calculated.resolves_to_number()) {
auto maybe_number = calculated.resolve_number(resolution_context);
if (!maybe_number.has_value())
return {};
return normalized(maybe_number.value());
}
if (calculated.resolves_to_percentage()) {
auto maybe_percentage = calculated.resolve_percentage(resolution_context);
if (!maybe_percentage.has_value())
return {};
return normalized(maybe_percentage.value().value() * 255 / 100);
}
}
return 0;
};
auto resolve_alpha_to_u8 = [&resolution_context](CSSStyleValue const& style_value) -> Optional<u8> {
auto alpha_0_1 = resolve_alpha(style_value, resolution_context);
if (alpha_0_1.has_value())
return llround(clamp(alpha_0_1.value() * 255.0f, 0.0f, 255.0f));
return {};
};
auto r_val = resolve_rgb_to_u8(m_properties.r);
auto g_val = resolve_rgb_to_u8(m_properties.g);
auto b_val = resolve_rgb_to_u8(m_properties.b);
auto alpha_val = resolve_alpha_to_u8(m_properties.alpha);
if (!r_val.has_value() || !g_val.has_value() || !b_val.has_value() || !alpha_val.has_value())
return {};
return Color(r_val.value(), g_val.value(), b_val.value(), alpha_val.value());
}
bool CSSRGB::equals(CSSStyleValue const& other) const
{
if (type() != other.type())
return false;
auto const& other_color = other.as_color();
if (color_type() != other_color.color_type())
return false;
auto const& other_rgb = static_cast<CSSRGB const&>(other_color);
return m_properties == other_rgb.m_properties;
}
// https://www.w3.org/TR/css-color-4/#serializing-sRGB-values
String CSSRGB::to_string(SerializationMode mode) const
{
if (mode != SerializationMode::ResolvedValue && m_properties.name.has_value())
return m_properties.name.value().to_string().to_ascii_lowercase();
if (auto color = to_color({}, {}); color.has_value())
return serialize_a_srgb_value(color.value());
StringBuilder builder;
builder.append("rgb("sv);
serialize_color_component(builder, mode, m_properties.r, 255, 0, 255);
builder.append(" "sv);
serialize_color_component(builder, mode, m_properties.g, 255, 0, 255);
builder.append(" "sv);
serialize_color_component(builder, mode, m_properties.b, 255, 0, 255);
if ((!m_properties.alpha->is_number() || m_properties.alpha->as_number().number() < 1) && (!m_properties.alpha->is_percentage() || m_properties.alpha->as_percentage().percentage().as_fraction() < 1)) {
builder.append(" / "sv);
serialize_alpha_component(builder, mode, m_properties.alpha);
}
builder.append(")"sv);
return builder.to_string_without_validation();
}
}