ladybird/Userland/Libraries/LibWeb/Painting/MarkerPaintable.cpp

/*
 * Copyright (c) 2018-2022, Andreas Kling <kling@serenityos.org>
 *
 * SPDX-License-Identifier: BSD-2-Clause
 */

#include <LibGfx/StylePainter.h>
#include <LibWeb/Layout/ListItemMarkerBox.h>
#include <LibWeb/Painting/MarkerPaintable.h>

namespace Web::Painting {

NonnullRefPtr<MarkerPaintable> MarkerPaintable::create(Layout::ListItemMarkerBox const& layout_box)
{
    return adopt_ref(*new MarkerPaintable(layout_box));
}

MarkerPaintable::MarkerPaintable(Layout::ListItemMarkerBox const& layout_box)
    : PaintableBox(layout_box)
{
}

Layout::ListItemMarkerBox const& MarkerPaintable::layout_box() const
{
    return static_cast<Layout::ListItemMarkerBox const&>(layout_node());
}

void MarkerPaintable::paint(PaintContext& context, PaintPhase phase) const
{
    if (phase != PaintPhase::Foreground)
        return;

    auto enclosing = enclosing_int_rect(absolute_rect());

    if (auto const* list_style_image = layout_box().list_style_image_bitmap()) {
        context.painter().blit(enclosing.location(), *list_style_image, list_style_image->rect());
        return;
    }

    auto color = computed_values().color();

    int marker_width = (int)enclosing.height() / 2;
    Gfx::IntRect marker_rect { 0, 0, marker_width, marker_width };
    marker_rect.center_within(enclosing);

    switch (layout_box().list_style_type()) {
    case CSS::ListStyleType::Square:
        context.painter().fill_rect(marker_rect, color);
        break;
    case CSS::ListStyleType::Circle:
        // For some reason for draw_ellipse() the ellipse is outside of the rect while for fill_ellipse() the ellipse is inside.
        // Scale the marker_rect with sqrt(2) to get an ellipse arc (circle) that appears as if it was inside of the marker_rect.
        marker_rect.set_height(marker_rect.height() / 1.41);
        marker_rect.set_width(marker_rect.width() / 1.41);
        marker_rect.center_within(enclosing);
        context.painter().draw_ellipse_intersecting(marker_rect, color);
        break;
    case CSS::ListStyleType::Disc:
        context.painter().fill_ellipse(marker_rect, color);
        break;
    case CSS::ListStyleType::Decimal:
    case CSS::ListStyleType::DecimalLeadingZero:
    case CSS::ListStyleType::LowerAlpha:
    case CSS::ListStyleType::LowerLatin:
    case CSS::ListStyleType::LowerRoman:
    case CSS::ListStyleType::UpperAlpha:
    case CSS::ListStyleType::UpperLatin:
    case CSS::ListStyleType::UpperRoman:
        if (layout_box().text().is_null())
            break;
        context.painter().draw_text(enclosing, layout_box().text(), Gfx::TextAlignment::Center);
        break;
    case CSS::ListStyleType::None:
        return;

    default:
        VERIFY_NOT_REACHED();
    }
}

}