/*
 * Copyright (c) 2025 Proton AG
 *
 * This file is part of ProtonVPN.
 *
 * ProtonVPN is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * ProtonVPN 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with ProtonVPN.  If not, see <https://www.gnu.org/licenses/>.
 */

using System;
using System.IO;
using System.Threading;
using ProtonVPN.Logging.Contracts;
using ProtonVPN.Logging.Contracts.Events.AppLogs;

namespace ProtonVPN.Vpn.SynchronizationEvent;

/// <summary>
/// Provides access to system synchronization events.
/// </summary>
internal class SystemSynchronizationEvents : ISynchronizationEvents
{
    private readonly ILogger _logger;

    public SystemSynchronizationEvents(ILogger logger)
    {
        _logger = logger;
    }

    public ISynchronizationEvent SynchronizationEvent(string eventName)
    {
        try
        {
            if (EventWaitHandle.TryOpenExisting(eventName, out EventWaitHandle? eventWaitHandle))
            {
                return new SystemSynchronizationEvent(eventWaitHandle);
            }
        }
        catch (UnauthorizedAccessException ex)
        {
            LogException(ex);
        }
        catch (IOException ex)
        {
            LogException(ex);
        }
        return new NullSynchronizationEvent(); 

        void LogException(Exception e)
        {
            _logger.Warn<AppLog>($"Synchronization: Failed to open event {eventName}.", e);
        }
    }
}