namespace ASC.Data.Backup
{
    [Scope]
    public class BackupAjaxHandler
    {
        private readonly TenantManager _tenantManager;
        private readonly MessageService _messageService;
        private readonly CoreBaseSettings _coreBaseSettings;
        private readonly CoreConfiguration _coreConfiguration;
        private readonly PermissionContext _permissionContext;
        private readonly SecurityContext _securityContext;
        private readonly UserManager _userManager;
        private readonly TenantExtra _tenantExtra;
        private readonly ConsumerFactory _consumerFactory;
        private readonly BackupFileUploadHandler _backupFileUploadHandler;
        private readonly BackupService _backupService;

        #region backup

        public BackupAjaxHandler(
            BackupService backupService,
            TenantManager tenantManager,
            MessageService messageService,
            CoreBaseSettings coreBaseSettings,
            CoreConfiguration coreConfiguration,
            PermissionContext permissionContext,
            SecurityContext securityContext,
            UserManager userManager,
            TenantExtra tenantExtra,
            ConsumerFactory consumerFactory,
            BackupFileUploadHandler backupFileUploadHandler)
        {
            _tenantManager = tenantManager;
            _messageService = messageService;
            _coreBaseSettings = coreBaseSettings;
            _coreConfiguration = coreConfiguration;
            _permissionContext = permissionContext;
            _securityContext = securityContext;
            _userManager = userManager;
            _tenantExtra = tenantExtra;
            _consumerFactory = consumerFactory;
            _backupFileUploadHandler = backupFileUploadHandler;
            _backupService = backupService;
        }

        public void StartBackup(BackupStorageType storageType, Dictionary<string, string> storageParams, bool backupMail)
        {
            DemandPermissionsBackup();

            var backupRequest = new StartBackupRequest
            {
                TenantId = GetCurrentTenantId(),
                UserId = _securityContext.CurrentAccount.ID,
                BackupMail = backupMail,
                StorageType = storageType,
                StorageParams = storageParams
            };

            switch (storageType)
            {
                case BackupStorageType.ThridpartyDocuments:
                case BackupStorageType.Documents:
                    backupRequest.StorageBasePath = storageParams["folderId"];
                    break;
                case BackupStorageType.Local:
                    if (!_coreBaseSettings.Standalone)
                    {
                        throw new Exception("Access denied");
                    }

                    backupRequest.StorageBasePath = storageParams["filePath"];
                    break;
            }

            _messageService.Send(MessageAction.StartBackupSetting);

            _backupService.StartBackup(backupRequest);
        }

        public BackupProgress GetBackupProgress()
        {
            DemandPermissionsBackup();

            return _backupService.GetBackupProgress(GetCurrentTenantId());
        }

        public BackupProgress GetBackupProgress(int tenantId)
        {
            DemandPermissionsBackup();

            return _backupService.GetBackupProgress(tenantId);
        }

        public void DeleteBackup(Guid id)
        {
            DemandPermissionsBackup();

            _backupService.DeleteBackup(id);
        }

        public void DeleteAllBackups()
        {
            DemandPermissionsBackup();

            _backupService.DeleteAllBackups(GetCurrentTenantId());
        }

        public List<BackupHistoryRecord> GetBackupHistory()
        {
            DemandPermissionsBackup();
            return _backupService.GetBackupHistory(GetCurrentTenantId());
        }

        public void CreateSchedule(BackupStorageType storageType, Dictionary<string, string> storageParams, int backupsStored, CronParams cronParams, bool backupMail)
        {
            DemandPermissionsBackup();

            if (!SetupInfo.IsVisibleSettings("AutoBackup"))
            {
                throw new InvalidOperationException(Resource.ErrorNotAllowedOption);
            }

            ValidateCronSettings(cronParams);

            var scheduleRequest = new CreateScheduleRequest
            {
                TenantId = _tenantManager.GetCurrentTenant().TenantId,
                BackupMail = backupMail,
                Cron = cronParams.ToString(),
                NumberOfBackupsStored = backupsStored,
                StorageType = storageType,
                StorageParams = storageParams
            };

            switch (storageType)
            {
                case BackupStorageType.ThridpartyDocuments:
                case BackupStorageType.Documents:
                    scheduleRequest.StorageBasePath = storageParams["folderId"];
                    break;
                case BackupStorageType.Local:
                    if (!_coreBaseSettings.Standalone)
                    {
                        throw new Exception("Access denied");
                    }

                    scheduleRequest.StorageBasePath = storageParams["filePath"];
                    break;
            }

            _backupService.CreateSchedule(scheduleRequest);
        }

        public Schedule GetSchedule()
        {
            DemandPermissionsBackup();

            ScheduleResponse response;

            response = _backupService.GetSchedule(GetCurrentTenantId());
            if (response == null)
            {
                return null;
            }

            var schedule = new Schedule
            {
                StorageType = response.StorageType,
                StorageParams = response.StorageParams.ToDictionary(r => r.Key, r => r.Value) ?? new Dictionary<string, string>(),
                CronParams = new CronParams(response.Cron),
                BackupMail = response.BackupMail.NullIfDefault(),
                BackupsStored = response.NumberOfBackupsStored.NullIfDefault(),
                LastBackupTime = response.LastBackupTime
            };

            if (response.StorageType == BackupStorageType.CustomCloud)
            {
                var amazonSettings = _coreConfiguration.GetSection<AmazonS3Settings>();

                var consumer = _consumerFactory.GetByKey<DataStoreConsumer>("s3");
                if (!consumer.IsSet)
                {
                    consumer["acesskey"] = amazonSettings.AccessKeyId;
                    consumer["secretaccesskey"] = amazonSettings.SecretAccessKey;

                    consumer["bucket"] = amazonSettings.Bucket;
                    consumer["region"] = amazonSettings.Region;
                }

                schedule.StorageType = BackupStorageType.ThirdPartyConsumer;
                schedule.StorageParams = consumer.AdditionalKeys.ToDictionary(r => r, r => consumer[r]);
                schedule.StorageParams.Add("module", "S3");

                var Schedule = new CreateScheduleRequest
                {
                    TenantId = _tenantManager.GetCurrentTenant().TenantId,
                    BackupMail = schedule.BackupMail != null && (bool)schedule.BackupMail,
                    Cron = schedule.CronParams.ToString(),
                    NumberOfBackupsStored = schedule.BackupsStored == null ? 0 : (int)schedule.BackupsStored,
                    StorageType = schedule.StorageType,
                    StorageParams = schedule.StorageParams
                };

                _backupService.CreateSchedule(Schedule);

            }
            else if (response.StorageType != BackupStorageType.ThirdPartyConsumer)
            {
                schedule.StorageParams["folderId"] = response.StorageBasePath;
            }

            return schedule;
        }

        public void DeleteSchedule()
        {
            DemandPermissionsBackup();

            _backupService.DeleteSchedule(GetCurrentTenantId());

        }

        private void DemandPermissionsBackup()
        {
            _permissionContext.DemandPermissions(SecutiryConstants.EditPortalSettings);

            if (!SetupInfo.IsVisibleSettings(ManagementType.Backup.ToString()))
            {
                throw new BillingException(Resource.ErrorNotAllowedOption, "Backup");
            }
        }

        #endregion

        #region restore

        public void StartRestore(string backupId, BackupStorageType storageType, Dictionary<string, string> storageParams, bool notify)
        {
            DemandPermissionsRestore();

            var restoreRequest = new StartRestoreRequest
            {
                TenantId = GetCurrentTenantId(),
                NotifyAfterCompletion = notify,
                StorageParams = storageParams
            };

            if (Guid.TryParse(backupId, out var guidBackupId))
            {
                restoreRequest.BackupId = guidBackupId;
            }
            else
            {
                restoreRequest.StorageType = storageType;
                restoreRequest.FilePathOrId = storageParams["filePath"];

                if (restoreRequest.StorageType == BackupStorageType.Local && !_coreBaseSettings.Standalone)
                {
                    restoreRequest.FilePathOrId = _backupFileUploadHandler.GetFilePath();
                }
            }

            _backupService.StartRestore(restoreRequest);
        }

        public BackupProgress GetRestoreProgress()
        {
            BackupProgress result;

            var tenant = _tenantManager.GetCurrentTenant();
            result = _backupService.GetRestoreProgress(tenant.TenantId);

            return result;
        }

        private void DemandPermissionsRestore()
        {
            _permissionContext.DemandPermissions(SecutiryConstants.EditPortalSettings);

            if (!SetupInfo.IsVisibleSettings("Restore") ||
                (!_coreBaseSettings.Standalone && !_tenantManager.GetTenantQuota(_tenantManager.GetCurrentTenant().TenantId).Restore))
            {
                throw new BillingException(Resource.ErrorNotAllowedOption, "Restore");
            }
        }

        #endregion

        #region transfer

        public void StartTransfer(string targetRegion, bool notifyUsers, bool transferMail)
        {
            DemandPermissionsTransfer();

            _messageService.Send(MessageAction.StartTransferSetting);
            _backupService.StartTransfer(
                new StartTransferRequest
                {
                    TenantId = GetCurrentTenantId(),
                    TargetRegion = targetRegion,
                    BackupMail = transferMail,
                    NotifyUsers = notifyUsers
                });

        }

        public BackupProgress GetTransferProgress()
        {
            return _backupService.GetTransferProgress(GetCurrentTenantId());
        }

        private void DemandPermissionsTransfer()
        {
            _permissionContext.DemandPermissions(SecutiryConstants.EditPortalSettings);

            var currentUser = _userManager.GetUsers(_securityContext.CurrentAccount.ID);
            if (!SetupInfo.IsVisibleSettings(ManagementType.Migration.ToString())
                || !currentUser.IsOwner(_tenantManager.GetCurrentTenant())
                || !SetupInfo.IsSecretEmail(currentUser.Email) && !_tenantExtra.GetTenantQuota().HasMigration)
            {
                throw new InvalidOperationException(Resource.ErrorNotAllowedOption);
            }
        }

        #endregion

        public string GetTmpFolder()
        {
            return _backupService.GetTmpFolder();
        }

        private static void ValidateCronSettings(CronParams cronParams)
        {
            new CronExpression(cronParams.ToString());
        }

        private int GetCurrentTenantId()
        {
            return _tenantManager.GetCurrentTenant().TenantId;
        }

        public class Schedule
        {
            public BackupStorageType StorageType { get; set; }
            public Dictionary<string, string> StorageParams { get; set; }
            public CronParams CronParams { get; set; }
            public bool? BackupMail { get; set; }
            public int? BackupsStored { get; set; }
            public DateTime LastBackupTime { get; set; }
        }

        public class CronParams
        {
            public BackupPeriod Period { get; set; }
            public int Hour { get; set; }
            public int Day { get; set; }

            public CronParams()
            {
            }

            public CronParams(string cronString)
            {
                var tokens = cronString.Split(' ');
                Hour = Convert.ToInt32(tokens[2]);
                if (tokens[3] != "?")
                {
                    Period = BackupPeriod.EveryMonth;
                    Day = Convert.ToInt32(tokens[3]);
                }
                else if (tokens[5] != "*")
                {
                    Period = BackupPeriod.EveryWeek;
                    Day = Convert.ToInt32(tokens[5]);
                }
                else
                {
                    Period = BackupPeriod.EveryDay;
                }
            }

            public override string ToString()
            {
                return Period switch
                {
                    BackupPeriod.EveryDay => string.Format("0 0 {0} ? * *", Hour),
                    BackupPeriod.EveryMonth => string.Format("0 0 {0} {1} * ?", Hour, Day),
                    BackupPeriod.EveryWeek => string.Format("0 0 {0} ? * {1}", Hour, Day),
                    _ => base.ToString(),
                };
            }
        }

        public enum BackupPeriod
        {
            EveryDay = 0,
            EveryWeek = 1,
            EveryMonth = 2
        }
    }
}