// Copyright (c) .NET Foundation. All rights reserved.
// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.

using System;
using Microsoft.Extensions.Logging;

namespace Libuv
{
  public class LibuvTrace : ILibuvTrace
  {
    // ConnectionRead: Reserved: 3

    private static readonly Action<ILogger, string, Exception> _connectionPause =
      LoggerMessage.Define<string>(LogLevel.Debug, new EventId(4, nameof(ConnectionPause)), @"Connection id ""{ConnectionId}"" paused.");

    private static readonly Action<ILogger, string, Exception> _connectionResume =
      LoggerMessage.Define<string>(LogLevel.Debug, new EventId(5, nameof(ConnectionResume)), @"Connection id ""{ConnectionId}"" resumed.");

    private static readonly Action<ILogger, string, Exception> _connectionReadFin =
      LoggerMessage.Define<string>(LogLevel.Debug, new EventId(6, nameof(ConnectionReadFin)), @"Connection id ""{ConnectionId}"" received FIN.");

    private static readonly Action<ILogger, string, string, Exception> _connectionWriteFin =
      LoggerMessage.Define<string, string>(LogLevel.Debug, new EventId(7, nameof(ConnectionWriteFin)), @"Connection id ""{ConnectionId}"" sending FIN because: ""{Reason}""");

    // ConnectionWrite: Reserved: 11

    // ConnectionWriteCallback: Reserved: 12

    private static readonly Action<ILogger, string, Exception> _connectionError =
      LoggerMessage.Define<string>(LogLevel.Debug, new EventId(14, nameof(ConnectionError)), @"Connection id ""{ConnectionId}"" communication error.");

    private static readonly Action<ILogger, string, Exception> _connectionReset =
      LoggerMessage.Define<string>(LogLevel.Debug, new EventId(19, nameof(ConnectionReset)), @"Connection id ""{ConnectionId}"" reset.");

    private readonly ILogger _logger;

    public LibuvTrace(ILogger logger) => _logger = logger;

    public void ConnectionRead(string connectionId, int count)
    {
      // Don't log for now since this could be *too* verbose.
      // Reserved: Event ID 3
    }

    public void ConnectionReadFin(string connectionId)
    {
      _connectionReadFin(_logger, connectionId, null);
    }

    public void ConnectionWriteFin(string connectionId, string reason)
    {
      _connectionWriteFin(_logger, connectionId, reason, null);
    }

    public void ConnectionWrite(string connectionId, int count)
    {
      // Don't log for now since this could be *too* verbose.
      // Reserved: Event ID 11
    }

    public void ConnectionWriteCallback(string connectionId, int status)
    {
      // Don't log for now since this could be *too* verbose.
      // Reserved: Event ID 12
    }

    public void ConnectionError(string connectionId, Exception ex)
    {
      _connectionError(_logger, connectionId, ex);
    }

    public void ConnectionReset(string connectionId)
    {
      _connectionReset(_logger, connectionId, null);
    }

    public void ConnectionPause(string connectionId)
    {
      _connectionPause(_logger, connectionId, null);
    }

    public void ConnectionResume(string connectionId)
    {
      _connectionResume(_logger, connectionId, null);
    }

    public IDisposable BeginScope<TState>(TState state) => _logger.BeginScope(state);

    public bool IsEnabled(LogLevel logLevel) => _logger.IsEnabled(logLevel);

    public void Log<TState>(LogLevel logLevel, EventId eventId, TState state, Exception exception, Func<TState, Exception, string> formatter)
      => _logger.Log(logLevel, eventId, state, exception, formatter);
  }
}