using System;

using System.Collections.Concurrent;

using System.Collections.Generic;

using System.Threading;

using ServiceStack.Logging;

namespace ServiceStack.Redis

{

/// <summary>

/// Don't immediately kill connections of active clients after failover to give them a chance to dispose gracefully.

/// Deactivating clients are automatically cleared from the pool.

/// </summary>

internal static class RedisState

{

private static ILog log = LogManager.GetLogger(typeof(RedisState));

internal static long TotalFailovers = 0;

internal static long TotalDeactivatedClients = 0;

internal static long TotalFailedSentinelWorkers = 0;

internal static long TotalForcedMasterFailovers = 0;

internal static long TotalInvalidMasters = 0;

internal static long TotalNoMastersFound = 0;

internal static long TotalClientsCreated = 0;

internal static long TotalClientsCreatedOutsidePool = 0;

internal static long TotalSubjectiveServersDown = 0;

internal static long TotalObjectiveServersDown = 0;

internal static readonly ConcurrentDictionary<RedisClient, DateTime> DeactivatedClients = new ConcurrentDictionary<RedisClient, DateTime>();

internal static void DeactivateClient(RedisClient client)

{

Interlocked.Increment(ref TotalDeactivatedClients);

if (RedisConfig.DeactivatedClientsExpiry == TimeSpan.Zero)

{

client.DisposeConnection();

return;

}

var deactivatedAt = client.DeactivatedAt ?? DateTime.UtcNow;

client.DeactivatedAt = deactivatedAt;

if (!DeactivatedClients.TryAdd(client, deactivatedAt))

client.DisposeConnection();

}

internal static void DisposeExpiredClients()

{

if (RedisConfig.DeactivatedClientsExpiry == TimeSpan.Zero || DeactivatedClients.Count == 0)

return;

var now = DateTime.UtcNow;

var removeDisposed = new List<RedisClient>();

foreach (var entry in DeactivatedClients)

{

try

{

if (now - entry.Value <= RedisConfig.DeactivatedClientsExpiry)

continue;

if (log.IsDebugEnabled)

log.Debug("Disposed Deactivated Client: {0}".Fmt(entry.Key.GetHostString()));

entry.Key.DisposeConnection();

removeDisposed.Add(entry.Key);

}

catch

{

removeDisposed.Add(entry.Key);

}

}

if (removeDisposed.Count == 0)

return;

var dict = ((IDictionary<RedisClient, DateTime>)DeactivatedClients);

foreach (var client in removeDisposed)

{

dict.Remove(client);

}

}

internal static void DisposeAllDeactivatedClients()

{

if (RedisConfig.DeactivatedClientsExpiry == TimeSpan.Zero)

return;

var allClients = DeactivatedClients.Keys.ToArray();

DeactivatedClients.Clear();

foreach (var client in allClients)

{

if (log.IsDebugEnabled)

log.Debug("Disposed Deactivated Client (All): {0}".Fmt(client.GetHostString()));

client.DisposeConnection();

}

}

}

}