Source/WebCore/dom/make-event-names.py

#!/usr/bin/env python3
#
# Copyright (C) 2024 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:
# 1. Redistributions of source code must retain the above copyright
#    notice, this list of conditions and the following disclaimer.
# 2. 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.
#
# THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS 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 APPLE INC. OR ITS 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.

import argparse
import json


def lowercase_first_letter(string):
    return string[0].lower() + string[1:] if len(string) and string[1].islower() else string


def main():
    parser = argparse.ArgumentParser(description='Generate EventNames.h')
    parser.add_argument('--event-names')
    args = parser.parse_args()

    with open(args.event_names, 'r', encoding='utf-8') as event_names_file:
        event_names_input = json.load(event_names_file)

    with open('EventNames.h', 'w') as output_file:
        def write(text):
            output_file.write(text)

        def writeln(text):
            write(text + '\n')

        writeln('''/*
 * Copyright (C) 2005-2024 Apple Inc. All rights reserved.
 * Copyright (C) 2006 Jon Shier (jshier@iastate.edu)
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public License
 * along with this library; see the file COPYING.LIB.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA 02110-1301, USA.
 *
 */

#pragma once

#include <WebCore/ThreadGlobalData.h>
#include <array>
#include <functional>
#include <wtf/HashSet.h>
#include <wtf/OptionSet.h>
#include <wtf/RobinHoodHashMap.h>
#include <wtf/text/AtomString.h>
#include <wtf/text/AtomStringHash.h>

namespace WebCore {

enum class EventType : uint16_t {
    custom = 0,''')

        category_map = {}
        for name in sorted(event_names_input.keys()):
            entry = event_names_input[name]
            for event_category in entry.get('categories', []):
                category_map.setdefault(event_category, [])
                category_map[event_category].append(name)
            conditional = entry.get('conditional', None)
            if conditional:
                writeln(f'#if {conditional}')
            writeln(f'    {name},')
            if conditional:
                writeln('#endif')

        writeln('''};

enum class EventCategory : uint16_t {''')

        bit_shift = 0
        for category in sorted(category_map.keys()):
            writeln(f'    {category} = 1u << {bit_shift},')
            bit_shift += 1

        writeln('''};

class EventTypeInfo {
public:
    enum class DefaultEventHandler : bool { No, Yes };

    EventTypeInfo()
        : m_type(EventType::custom)
    { }

    EventTypeInfo(EventType type, OptionSet<EventCategory> categories, DefaultEventHandler defaultEventHandler)
        : m_type(type)
        , m_categories(categories.toRaw())
        , m_hasDefaultEventHandler(defaultEventHandler == DefaultEventHandler::Yes)
    { }

    EventType type() const { return static_cast<EventType>(m_type); }
    bool isInCategory(EventCategory category) const { return OptionSet<EventCategory>::fromRaw(m_categories).contains(category); }
    bool hasDefaultEventHandler() const { return m_hasDefaultEventHandler; }

private:
    EventType m_type;
    uint16_t m_categories : 15 { 0 };
    uint16_t m_hasDefaultEventHandler : 1 { false };
};

struct EventNames {
    WTF_MAKE_NONCOPYABLE(EventNames); WTF_DEPRECATED_MAKE_FAST_ALLOCATED(EventNames);
public:''')

        for name in sorted(event_names_input.keys()):
            entry = event_names_input[name]
            conditional = entry.get('conditional', None)
            if conditional:
                writeln(f'#if {conditional}')
            writeln(f'    const AtomString {name}Event;')
            if conditional:
                writeln('#endif')

        writeln('''
    EventTypeInfo typeInfoForEvent(const AtomString&) const;

    template<class... Args>
    static std::unique_ptr<EventNames> create(Args&&... args)
    {
        return std::unique_ptr<EventNames>(new EventNames(std::forward<Args>(args)...));
    }
''')
        writeln(f'    std::array<const AtomString, {len(event_names_input)}> allEventNames() const;')
        writeln(f'    WTF::HashSet<AtomString> allEventHandlerNames() const;')
        writeln(f'')
        writeln(f'    static constexpr std::array timedEvents {{')
        for name in category_map['EventTimingEligible']:
            entry = event_names_input[name]
            conditional = entry.get('conditional', None)
            writeln(f'#if {conditional}') if conditional else None
            writeln(f'        EventType::{name},')
            writeln(f'#endif') if conditional else None
        writeln(f'    }};')
        writeln(f'')
        writeln(f'    const AtomString& eventNameFromEventType(EventType) const;')
        writeln('''
private:
    EventNames();

    MemoryCompactLookupOnlyRobinHoodHashMap<AtomString, EventTypeInfo> m_typeInfoMap;
};

const EventNames& eventNames();

inline const EventNames& eventNames()
{
    return threadGlobalDataSingleton().eventNames();
}

inline EventTypeInfo EventNames::typeInfoForEvent(const AtomString& eventType) const
{
    return m_typeInfoMap.inlineGet(eventType);
}

} // namespace WebCore''')

    with open('EventNames.cpp', 'w') as output_file:
        def writeln(text):
            output_file.write(text + '\n')
        writeln('''/*
 * Copyright (C) 2005-2024 Apple Inc. All rights reserved.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public License
 * along with this library; see the file COPYING.LIB.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA 02110-1301, USA.
 *
 */

#include "config.h"
#include "EventNames.h"

namespace WebCore {
''')

        # Generate static constexpr StaticStringImpl declarations
        for name in sorted(event_names_input.keys()):
            conditional = event_names_input[name].get('conditional', None)
            if conditional:
                writeln(f'#if {conditional}')
            writeln(f'static constexpr StringImpl::StaticStringImpl {name}Data("{name}", StringImpl::StringAtom);')
            if conditional:
                writeln('#endif')

        writeln('')

        # Generate constructor using StaticStringImpl references
        writeln('EventNames::EventNames()')

        delimiter = ':'
        for name in sorted(event_names_input.keys()):
            conditional = event_names_input[name].get('conditional', None)
            if conditional:
                writeln(f'#if {conditional}')
            writeln(f'    {delimiter} {name}Event({name}Data)')
            delimiter = ','
            if conditional:
                writeln('#endif')

        # m_typeInfoMap uses already-initialized member variables as keys
        writeln(f'    {delimiter} m_typeInfoMap({{')
        for name in sorted(event_names_input.keys()):
            entry = event_names_input[name]
            conditional = entry.get('conditional', None)
            if conditional:
                writeln(f'#if {conditional}')
            write(f'        {{ \"{name}\"_s, {{ EventType::{name}, {{ ')
            categories = entry.get('categories', [])
            if categories:
                for category in categories[:-1]:
                    write(f'EventCategory::{category}, ')
                write(f'EventCategory::{categories[-1]} ')
            write('}, ')
            if entry.get('defaultEventHandler', False):
                write('EventTypeInfo::DefaultEventHandler::Yes')
            else:
                write('EventTypeInfo::DefaultEventHandler::No')
            writeln(' } },')
            if conditional:
                writeln('#endif')
        writeln('    })')
        writeln('{ }')
        writeln('')
        writeln(f'std::array<const AtomString, {len(event_names_input)}> EventNames::allEventNames() const')
        writeln('{')
        writeln('    return { {')
        for name in sorted(event_names_input.keys()):
            conditional = event_names_input[name].get('conditional', None)
            if conditional:
                writeln(f'#if {conditional}')
            writeln(f'        {name}Event,')
            if conditional:
                writeln(f'#endif')
        writeln('''    } };''')
        writeln('}')
        writeln('')
        writeln(f'WTF::HashSet<AtomString> EventNames::allEventHandlerNames() const')
        writeln('{')
        writeln(f'    WTF::HashSet<AtomString> set;')
        for name in sorted(event_names_input.keys()):
            conditional = event_names_input[name].get('conditional', None)
            if conditional:
                writeln(f'#if {conditional}')
            writeln(f'    set.add("on{name.lower()}"_s);')
            if conditional:
                writeln(f'#endif')
        writeln('    return set;')
        writeln('}')
        writeln('')
        writeln(f'static constexpr std::array<const AtomString EventNames::*, {len(event_names_input)}> eventStringInEventNames {{')
        for name in sorted(event_names_input.keys()):
            entry = event_names_input[name]
            conditional = entry.get('conditional', None)
            writeln(f'#if {conditional}') if conditional else None
            writeln(f'    &EventNames::{name}Event,')
            writeln(f'#endif') if conditional else None
        writeln('};')
        writeln('''
const AtomString& EventNames::eventNameFromEventType(EventType type) const {
    auto typeAsIndex = static_cast<size_t>(type) - 1;
    return this->*(eventStringInEventNames[typeAsIndex]);
}

} // namespace WebCore''')


if __name__ == '__main__':
    main()