serenity/Ladybird/AppKit/UI/LadybirdWebViewBridge.cpp

/*
 * Copyright (c) 2023, Tim Flynn <trflynn89@serenityos.org>
 *
 * SPDX-License-Identifier: BSD-2-Clause
 */

#include <Ladybird/HelperProcess.h>
#include <Ladybird/Types.h>
#include <Ladybird/Utilities.h>
#include <LibGfx/Font/FontDatabase.h>
#include <LibGfx/Rect.h>
#include <LibIPC/File.h>
#include <LibWeb/Crypto/Crypto.h>
#include <UI/LadybirdWebViewBridge.h>

#import <UI/Palette.h>

namespace Ladybird {

template<typename T>
static T scale_for_device(T size, float device_pixel_ratio)
{
    return size.template to_type<float>().scaled(device_pixel_ratio).template to_type<int>();
}

ErrorOr<NonnullOwnPtr<WebViewBridge>> WebViewBridge::create(Vector<Gfx::IntRect> screen_rects, float device_pixel_ratio, WebContentOptions const& web_content_options, Optional<StringView> webdriver_content_ipc_path, Web::CSS::PreferredColorScheme preferred_color_scheme)
{
    return adopt_nonnull_own_or_enomem(new (nothrow) WebViewBridge(move(screen_rects), device_pixel_ratio, web_content_options, move(webdriver_content_ipc_path), preferred_color_scheme));
}

WebViewBridge::WebViewBridge(Vector<Gfx::IntRect> screen_rects, float device_pixel_ratio, WebContentOptions const& web_content_options, Optional<StringView> webdriver_content_ipc_path, Web::CSS::PreferredColorScheme preferred_color_scheme)
    : m_screen_rects(move(screen_rects))
    , m_web_content_options(web_content_options)
    , m_webdriver_content_ipc_path(move(webdriver_content_ipc_path))
    , m_preferred_color_scheme(preferred_color_scheme)
{
    m_device_pixel_ratio = device_pixel_ratio;

    create_client();

    on_scroll_by_delta = [this](auto x_delta, auto y_delta) {
        auto position = m_viewport_rect.location();
        position.set_x(position.x() + x_delta);
        position.set_y(position.y() + y_delta);

        if (on_scroll_to_point)
            on_scroll_to_point(position);
    };

    on_scroll_into_view = [this](auto rect) {
        if (m_viewport_rect.contains(rect))
            return;

        auto position = m_viewport_rect.location();

        if (rect.top() < m_viewport_rect.top()) {
            position.set_y(rect.top());
        } else if (rect.top() > m_viewport_rect.top() && rect.bottom() > m_viewport_rect.bottom()) {
            position.set_y(rect.bottom() - m_viewport_rect.height());
        } else {
            return;
        }

        if (on_scroll_to_point)
            on_scroll_to_point(position);
    };

    on_scroll_to_point = [this](auto position) {
        if (on_scroll)
            on_scroll(to_widget_position(position));
    };
}

WebViewBridge::~WebViewBridge() = default;

void WebViewBridge::set_device_pixel_ratio(float device_pixel_ratio)
{
    m_device_pixel_ratio = device_pixel_ratio;
    client().async_set_device_pixels_per_css_pixel(m_device_pixel_ratio * m_zoom_level);
}

void WebViewBridge::set_system_visibility_state(bool is_visible)
{
    client().async_set_system_visibility_state(is_visible);
}

void WebViewBridge::set_viewport_rect(Gfx::IntRect viewport_rect, ForResize for_resize)
{
    viewport_rect.set_size(scale_for_device(viewport_rect.size(), m_device_pixel_ratio));
    m_viewport_rect = viewport_rect;

    client().async_set_viewport_rect(m_viewport_rect);
    request_repaint();

    if (for_resize == ForResize::Yes) {
        handle_resize();
    }
}

void WebViewBridge::update_palette()
{
    auto theme = create_system_palette();
    client().async_update_system_theme(move(theme));
}

void WebViewBridge::set_preferred_color_scheme(Web::CSS::PreferredColorScheme color_scheme)
{
    m_preferred_color_scheme = color_scheme;
    client().async_set_preferred_color_scheme(color_scheme);
}

void WebViewBridge::mouse_wheel_event(Gfx::IntPoint position, Gfx::IntPoint screen_position, GUI::MouseButton button, KeyModifier modifiers, int wheel_delta_x, int wheel_delta_y)
{
    client().async_mouse_wheel(to_content_position(position), screen_position, to_underlying(button), to_underlying(button), modifiers, wheel_delta_x, wheel_delta_y);
}

void WebViewBridge::mouse_down_event(Gfx::IntPoint position, Gfx::IntPoint screen_position, GUI::MouseButton button, KeyModifier modifiers)
{
    client().async_mouse_down(to_content_position(position), screen_position, to_underlying(button), to_underlying(button), modifiers);
}

void WebViewBridge::mouse_up_event(Gfx::IntPoint position, Gfx::IntPoint screen_position, GUI::MouseButton button, KeyModifier modifiers)
{
    client().async_mouse_up(to_content_position(position), screen_position, to_underlying(button), to_underlying(button), modifiers);
}

void WebViewBridge::mouse_move_event(Gfx::IntPoint position, Gfx::IntPoint screen_position, GUI::MouseButton button, KeyModifier modifiers)
{
    client().async_mouse_move(to_content_position(position), screen_position, 0, to_underlying(button), modifiers);
}

void WebViewBridge::mouse_double_click_event(Gfx::IntPoint position, Gfx::IntPoint screen_position, GUI::MouseButton button, KeyModifier modifiers)
{
    client().async_doubleclick(to_content_position(position), screen_position, button, to_underlying(button), modifiers);
}

void WebViewBridge::key_down_event(KeyCode key_code, KeyModifier modifiers, u32 code_point)
{
    client().async_key_down(key_code, modifiers, code_point);
}

void WebViewBridge::key_up_event(KeyCode key_code, KeyModifier modifiers, u32 code_point)
{
    client().async_key_up(key_code, modifiers, code_point);
}

Optional<WebViewBridge::Paintable> WebViewBridge::paintable()
{
    Gfx::Bitmap* bitmap = nullptr;
    Gfx::IntSize bitmap_size;

    if (m_client_state.has_usable_bitmap) {
        bitmap = m_client_state.front_bitmap.bitmap.ptr();
        bitmap_size = m_client_state.front_bitmap.last_painted_size;
    } else {
        bitmap = m_backup_bitmap.ptr();
        bitmap_size = m_backup_bitmap_size;
    }

    if (!bitmap)
        return {};
    return Paintable { *bitmap, bitmap_size };
}

void WebViewBridge::update_zoom()
{
    client().async_set_device_pixels_per_css_pixel(m_device_pixel_ratio * m_zoom_level);

    if (on_zoom_level_changed)
        on_zoom_level_changed();
}

Gfx::IntRect WebViewBridge::viewport_rect() const
{
    return m_viewport_rect;
}

Gfx::IntPoint WebViewBridge::to_content_position(Gfx::IntPoint widget_position) const
{
    return scale_for_device(widget_position, m_device_pixel_ratio);
}

Gfx::IntPoint WebViewBridge::to_widget_position(Gfx::IntPoint content_position) const
{
    return scale_for_device(content_position, inverse_device_pixel_ratio());
}

void WebViewBridge::create_client()
{
    m_client_state = {};

    auto candidate_web_content_paths = MUST(get_paths_for_helper_process("WebContent"sv));
    auto new_client = MUST(launch_web_content_process(*this, candidate_web_content_paths, m_web_content_options));

    m_client_state.client = new_client;
    m_client_state.client->on_web_content_process_crash = [this] {
        Core::deferred_invoke([this] {
            handle_web_content_process_crash();
        });
    };

    m_client_state.client_handle = MUST(Web::Crypto::generate_random_uuid());
    client().async_set_window_handle(m_client_state.client_handle);

    client().async_set_device_pixels_per_css_pixel(m_device_pixel_ratio);
    client().async_update_system_fonts(Gfx::FontDatabase::default_font_query(), Gfx::FontDatabase::fixed_width_font_query(), Gfx::FontDatabase::window_title_font_query());
    client().async_set_preferred_color_scheme(m_preferred_color_scheme);
    update_palette();

    if (!m_screen_rects.is_empty()) {
        // FIXME: Update the screens again if they ever change.
        client().async_update_screen_rects(m_screen_rects, 0);
    }

    if (m_webdriver_content_ipc_path.has_value()) {
        client().async_connect_to_webdriver(*m_webdriver_content_ipc_path);
    }
}

}