//using MessengerApi.Db;
//using MessengerBroker.Db;
//using Microsoft.EntityFrameworkCore;
//using System.Text.Json;

//namespace MessengerBroker.Handlers
//{
//    public class MasterHandler
//    {
//        private readonly Settings settings;

//        private readonly HttpClient httpClient = new HttpClient();

//        public async Task BeginSyncingWithMaster(Settings.MasterServer masterServer, CancellationToken ct = default)
//        {
//            while (!ct.IsCancellationRequested)
//            {
//                await Task.Delay(TimeSpan.FromSeconds(1));

//                var usersRequest = new HttpRequestMessage(HttpMethod.Get, $"{masterServer.BrokerApiUrl}/users");
//                usersRequest.Headers.Authorization = new System.Net.Http.Headers.AuthenticationHeaderValue("Bearer", this.settings.BrokerId.ToString());

//                var usersResponseMessage = await this.httpClient.SendAsync(usersRequest, ct);

//                if (!usersResponseMessage.IsSuccessStatusCode)
//                {
//                    continue;
//                }

//                var usersResponse = JsonSerializer.Deserialize<Model.Http.Users.UsersResponse>(await usersResponseMessage.Content.ReadAsStringAsync());

//                using (var broCtx = new BrokerDbContext(this.settings.MessengerBrokerDbConnectionString))
//                using (var apiCtx = new MessengerDbContext(this.settings.MessengerApiDbConnectionString))
//                {
//                    var updatedUsers = usersResponse.Users.Where(x => broCtx.Users.GetUserExists(x.Id)).ToList();
//                    updatedUsers.ForEach(async x => await this.UpdateUser(x, apiCtx));

//                    var deletedUsers = broCtx.Users.GetUsersExcept(usersResponse.Users.Select(x => x.Id)).ToList();
//                    deletedUsers.ForEach(async x => await this.RemoveUser(x.Id, broCtx, apiCtx));

//                    var addedUsers = usersResponse.Users.Where(x => !broCtx.Users.GetUserExists(x.Id)).ToList();
//                    addedUsers.ForEach(async x => await this.AddUser(x, masterServer.BrokerId, broCtx, apiCtx));

//                    foreach (var route in usersResponse.UserRoutes
//                        .Where(r => apiCtx.UserRoutes
//                            .Include(x => x.From)
//                            .Include(x => x.To)
//                            .Any(apir => apir.Id == r.Id && (apir.From.Id != r.FromId || apir.To.Id != r.ToId))))
//                    {
//                        var existing = apiCtx.UserRoutes.Include(x => x.From).Include(x => x.To).Single(x => x.Id == route.Id);
//                        existing.From = apiCtx.Users.Single(x => x.Id == route.FromId);
//                        existing.To = apiCtx.Users.Single(x => x.Id == route.ToId);
//                    }

//                    foreach (var deletedRoute in apiCtx.UserRoutes
//                        .Where(x => !usersResponse.UserRoutes.Any(r => r.Id == x.Id)))
//                    {
//                        apiCtx.UserRoutes.Remove(deletedRoute);
//                    }

//                    foreach (var addedRoute in usersResponse.UserRoutes
//                        .Where(r => !apiCtx.UserRoutes.Any(x => x.Id == r.Id)))
//                    {
//                        apiCtx.UserRoutes.Add(new MessengerApi.Db.Entities.UserRoute
//                        {
//                            Id = addedRoute.Id,
//                            From = apiCtx.Users.Single(x => x.Id == addedRoute.FromId),
//                            To = apiCtx.Users.Single(x => x.Id == addedRoute.ToId)
//                        });
//                    }

//                    broCtx.SaveChanges();
//                    apiCtx.SaveChanges();
//                }

//                var messagesRequest = new HttpRequestMessage(HttpMethod.Get, $"{masterServer.BrokerApiUrl}/messages");
//                messagesRequest.Headers.Authorization = new System.Net.Http.Headers.AuthenticationHeaderValue("Bearer", this.settings.BrokerId.ToString());

//                var messagesResponseMessage = await this.httpClient.SendAsync(messagesRequest, ct);

//                if (!messagesResponseMessage.IsSuccessStatusCode)
//                {
//                    continue;
//                }

//                var messagesResponse = JsonSerializer.Deserialize<Model.Http.Messages.MessagesResponse>(await messagesResponseMessage.Content.ReadAsStringAsync());

//                using (var broCtx = new BrokerDbContext(this.settings.MessengerBrokerDbConnectionString))
//                using (var apiCtx = new MessengerDbContext(this.settings.MessengerApiDbConnectionString))
//                {
//                    var addedMessages = messagesResponse.Messages
//                        .Where(m => broCtx.Messages.Any(x => x.BrokerId == masterServer.BrokerId && x.Id == m.Id) == false)
//                        .ToList();

//                    addedMessages.ForEach(x =>
//                    {
//                        broCtx.Messages.Add(new Db.Model.Message
//                        {
//                            BrokerId = masterServer.BrokerId,
//                            Id = x.Id
//                        });

//                        apiCtx.Messages.Add(new MessengerApi.Db.Entities.Message
//                        {
//                            Id = x.Id,
//                            CreatedUtc = x.CreatedUtc,
//                            From = x.From != null ? (apiCtx.Users.SingleOrDefault(u => u.Id == x.From.Value)) ?? null : null,
//                            To = x.To != null ? (apiCtx.Users.SingleOrDefault(u => u.Id == x.To.Value)) ?? null : null,
//                            IsAcknowledged = x.IsAcknowledged,
//                            IsDelivered = x.IsDelivered,
//                            Payload = x.Payload,
//                            PayloadId = x.PayloadId,
//                            PayloadLifespanInSeconds = x.PayloadLifespanInSeconds,
//                            PayloadTimestamp = x.PayloadTimestamp,
//                            PayloadType = x.PayloadType,
//                        });
//                    });

//                    var existingMessages = messagesResponse.Messages
//                        .Except(addedMessages)
//                        .ToList();

//                    existingMessages.ForEach(x =>
//                    {
//                        var existing = apiCtx.Messages.SingleOrDefault(a => a.Id ==  x.Id);

//                        if(existing != null && (existing.IsDelivered != x.IsDelivered || existing.IsAcknowledged != x.IsAcknowledged))
//                        {
//                            existing.IsDelivered = x.IsDelivered;
//                            existing.IsAcknowledged = x.IsAcknowledged;
//                        }
//                    });

//                    broCtx.SaveChanges();
//                    apiCtx.SaveChanges();
//                }
//            }
//        }

//        private async Task RemoveUser(Guid id, BrokerDbContext broCtx, MessengerDbContext apiCtx)
//        {
//            var broUser = await broCtx.Users.SingleOrDefaultAsync(x => x.Id == id);

//            if (broUser != null)
//            {
//                broCtx.Users.Remove(broUser);
//            }

//            var apiUser = await apiCtx.Users.SingleOrDefaultAsync(x => x.Id == id);

//            if (apiUser != null)
//            {
//                apiCtx.Users.Remove(apiUser);
//            }
//        }

//        private async Task AddUser(Model.Http.Users.UsersResponse.User user, Guid brokerId, BrokerDbContext broCtx, MessengerDbContext apiCtx)
//        {
//            if (broCtx.Users.GetUserExists(user.Id) == false)
//            {
//                broCtx.Users.Add(new Db.Model.User
//                {
//                    Id = user.Id,
//                    BrokerId = brokerId
//                });
//            }

//            if (apiCtx.Users.Any(x => x.Id == user.Id))
//            {
//                await this.UpdateUser(user, apiCtx);
//            }
//            else
//            {
//                await apiCtx.Users.AddAsync(new MessengerApi.Db.Entities.User
//                {
//                    Id = user.Id,
//                    ApiKey = user.ApiKey,
//                    CanReceive = user.CanReceive,
//                    CanSend = user.CanSend,
//                    IsEnabled = user.IsEnabled,
//                    Name = user.Name
//                });
//            }
//        }

//        private async Task UpdateUser(Model.Http.Users.UsersResponse.User user, MessengerDbContext apiCtx)
//        {
//            var apiUser = await apiCtx.Users.SingleAsync(x => x.Id == user.Id);
//            apiUser.ApiKey = user.ApiKey;
//            apiUser.CanReceive = user.CanReceive;
//            apiUser.CanSend = user.CanSend;
//            apiUser.IsEnabled = user.IsEnabled;
//            apiUser.Name = user.Name;
//        }
//    }
//}