using LearningOfficer.OA.Common.Attributes;
using LearningOfficer.OA.Common.Configs;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Options;
using RabbitMQ.Client;
using Serilog;

namespace LearningOfficer.OA.Infrastructure.RabbitMQ
{
    /// <summary>
    /// RabbitMQ 连接服务
    /// </summary>
    public class RabbitMQConnectionService : IAsyncDisposable
    {
        private readonly RabbitMQConfig _config;
        private IConnection? _connection;
        private bool _disposed = false;
        private readonly SemaphoreSlim _lock = new(1, 1);

        public RabbitMQConnectionService(IOptionsMonitor<RabbitMQConfig> config)
        {
            _config = config.CurrentValue;
        }

        /// <summary>
        /// 获取 RabbitMQ 连接
        /// </summary>
        /// <returns></returns>
        public async Task<IConnection> GetConnection()
        {
            if (_connection?.IsOpen == true)
            {
                return _connection;
            }
            await _lock.WaitAsync();
            try
            {
                if (_connection?.IsOpen == true)
                {
                    return _connection;
                }

                try
                {
                    var factory = new ConnectionFactory
                    {
                        HostName = _config.HostName,
                        Port = _config.Port,
                        UserName = _config.UserName,
                        Password = _config.Password,
                        VirtualHost = _config.VirtualHost,
                        AutomaticRecoveryEnabled = true,
                        NetworkRecoveryInterval = TimeSpan.FromSeconds(10)
                    };

                    _connection = await factory.CreateConnectionAsync();
                    _connection.ConnectionShutdownAsync += _connection_ConnectionShutdownAsync;

                    Log.Information("RabbitMQ 连接创建成功: {HostName}:{Port}", _config.HostName, _config.Port);

                    return _connection;
                }
                catch (Exception ex)
                {
                    Log.Error(ex, "RabbitMQ 连接创建失败: {HostName}:{Port}", _config.HostName, _config.Port);
                    throw;
                }
            }
            finally
            {
                _lock.Release();
            }
        }

        private async Task _connection_ConnectionShutdownAsync(object sender, global::RabbitMQ.Client.Events.ShutdownEventArgs @event)
        {
            Log.Warning("RabbitMQ 连接断开: {ReplyText}", @event.ReplyText);
            await Task.CompletedTask;
        }
        /// <summary>
        /// 创建通道
        /// </summary>
        public async Task<IChannel> CreateChannel()
        {
            var connection = await GetConnection();
            return await connection.CreateChannelAsync();
        }

        public async ValueTask DisposeAsync()
        {
            if (!_disposed)
            {
                if (_connection != null)
                {
                    _connection.ConnectionShutdownAsync -= _connection_ConnectionShutdownAsync;
                    await _connection.DisposeAsync();
                    Log.Information("RabbitMQ 连接已释放");
                }
                _disposed = true;
            }
            GC.SuppressFinalize(this);
        }
    }
}