ladybird/Userland/Libraries/LibWeb/CSS/Supports.cpp
Sam Atkins 2aac9f9258 LibWeb: Bring parse_a_declaration() to spec and add comments
User code now calls `parse_as_supports_condition()` which actually does
the conversion to a StyleProperty.
2022-03-30 18:43:07 +02:00

76 lines
1.7 KiB
C++

/*
* Copyright (c) 2021-2022, Sam Atkins <atkinssj@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <LibWeb/CSS/Parser/Parser.h>
#include <LibWeb/CSS/Supports.h>
namespace Web::CSS {
Supports::Supports(NonnullOwnPtr<Condition>&& condition)
: m_condition(move(condition))
{
m_matches = m_condition->evaluate();
}
bool Supports::Condition::evaluate() const
{
switch (type) {
case Type::Not:
return !children.first().evaluate();
case Type::And:
for (auto& child : children) {
if (!child.evaluate())
return false;
}
return true;
case Type::Or:
for (auto& child : children) {
if (child.evaluate())
return true;
}
return false;
}
VERIFY_NOT_REACHED();
}
bool Supports::InParens::evaluate() const
{
return value.visit(
[&](NonnullOwnPtr<Condition> const& condition) {
return condition->evaluate();
},
[&](Feature const& feature) {
return feature.evaluate();
},
[&](GeneralEnclosed const&) {
return false;
});
}
bool Supports::Declaration::evaluate() const
{
auto style_property = Parser({}, declaration).parse_as_supports_condition();
return style_property.has_value();
}
bool Supports::Selector::evaluate() const
{
auto style_property = Parser({}, selector).parse_as_selector();
return style_property.has_value();
}
bool Supports::Feature::evaluate() const
{
return value.visit(
[&](Declaration const& declaration) {
return declaration.evaluate();
},
[&](Selector const& selector) {
return selector.evaluate();
});
}
}