public async Task Login()

in App/src/Events-TenantUserApp/Controllers/AccountController.cs [43:99]
53 lines of code
6 McCabe index (conditional complexity)

        public async Task<ActionResult> Login(string tenant, string regEmail)
        {
            try
            {
                if (string.IsNullOrWhiteSpace(regEmail))
                {
                    var message = _localizer["Please type your email."];
                    DisplayMessage(message, "Error");
                }
                else
                {
                    var tenantDetails = (_catalogRepository.GetTenant(tenant)).Result;

                    if (tenantDetails != null)
                    {
                        SetTenantConfig(tenantDetails.TenantId, tenantDetails.TenantIdInString);

                        var customer = await _tenantRepository.GetCustomer(regEmail, tenantDetails.TenantId);

                        if (customer != null)
                        {
                            customer.TenantName = tenant;

                            var userSessions = HttpContext.Session.GetObjectFromJson<List<CustomerModel>>("SessionUsers");
                            if (userSessions == null)
                            {
                                userSessions = new List<CustomerModel>
                                {
                                    customer
                                };
                                HttpContext.Session.SetObjectAsJson("SessionUsers", userSessions);
                            }
                            else
                            {
                                userSessions.Add(customer);
                                HttpContext.Session.SetObjectAsJson("SessionUsers", userSessions);
                            }
                        }
                        else
                        {
                            var message = _localizer["The user does not exist."];
                            DisplayMessage(message, "Error");
                        }
                    }
                    else
                    {
                        return View("TenantError", tenant);
                    }
                }
            }
            catch (Exception ex)
            {
                _logger.LogError(0, ex, "Login failed for tenant {tenant}", tenant);
                return View("TenantError", tenant);
            }
            return Redirect(Request.Headers["Referer"].ToString());
        }