RE1-T117 PR#415 fixes

Author: ucswift

Core/Resgrid.Services/SubscriptionsService.cs

@@ -620,6 +620,12 @@ public async Task<double> GetAdjustedUpgradePriceAsync(int paymentId, int planId
 			var payment = await GetPaymentByIdAsync(paymentId);
 			var plan = await GetPlanByIdAsync(planId);
 
+			// Sometimes the payment comes back without its Plan navigation populated; hydrate it from PlanId
+			// before giving up, mirroring GetCurrentPaymentForDepartmentAsync, so a valid payment with a
+			// missing navigation can still be priced rather than failing immediately.
+			if (payment != null && payment.Plan == null)
+				payment.Plan = await GetPlanByIdAsync(payment.PlanId);
+
 			// GetPaymentByIdAsync/GetPlanByIdAsync return null when the Billing API is unavailable or the id
 			// isn't found. Every branch below dereferences payment, payment.Plan and plan and returns a price;
 			// silently returning 0 would mean a free upgrade, so fail loud rather than bill an outage-derived $0.

Web/Resgrid.Web/Areas/User/Controllers/SubscriptionController.cs

@@ -592,6 +592,11 @@ public async Task<IActionResult> BuyAddon(string planAddonId)
 		{
 			var model = new BuyAddonView();
 			model.PlanAddon = await _subscriptionsService.GetPlanAddonByIdAsync(planAddonId);
+			// GetPlanAddonByIdAsync returns null when the add-on id isn't found (or the Billing API is
+			// unavailable). Bail before dereferencing model.PlanAddon below (PlanAddonId / AddonType / PlanId).
+			if (model.PlanAddon == null)
+				return NotFound();
+
 			model.PlanAddonId = model.PlanAddon.PlanAddonId;
 			model.Department = await _departmentsService.GetDepartmentByIdAsync(DepartmentId);
 			var addonTypes = await _subscriptionsService.GetAllAddonPlansAsync();
@@ -620,6 +625,12 @@ public async Task<IActionResult> ManagePTTAddon()
 		{
 			var model = new BuyAddonView();
 			model.PlanAddon = await _subscriptionsService.GetPlanAddonByIdAsync("6f4c5f8b-584d-4291-8a7d-29bf97ae6aa9");
+			// GetPlanAddonByIdAsync returns null when the Billing API is unavailable / the add-on isn't found.
+			// The id here is hardcoded (a known product), so a null means a server/billing problem, not a bad
+			// request — surface a 500 instead of NRE'ing on model.PlanAddon below.
+			if (model.PlanAddon == null)
+				return StatusCode(StatusCodes.Status500InternalServerError, "Unable to load the PTT add-on. Please try again.");
+
 			model.PlanAddonId = model.PlanAddon.PlanAddonId;
 			model.Department = await _departmentsService.GetDepartmentByIdAsync(DepartmentId);
 
@@ -775,6 +786,11 @@ public async Task<IActionResult> GetStripeSession(int id, int count, string disc
 			var department = await _departmentsService.GetDepartmentByIdAsync(DepartmentId);
 			var user = _usersService.GetUserById(UserId);
 			var session = await _subscriptionsService.CreateStripeSessionForSub(DepartmentId, stripeCustomerId, plan.GetExternalKey(), plan.PlanId, user.Email, department.Name, count, discountCode);
+			// CreateStripeSessionForSub returns null when the Billing API is unavailable / Stripe session
+			// creation fails. Fail with a clear error instead of NRE'ing on session.CustomerId/SessionId below.
+			if (session == null)
+				return StatusCode(StatusCodes.Status500InternalServerError, "Unable to start the checkout session. Please try again.");
+
 			var subscription = await _subscriptionsService.GetActiveStripeSubscriptionAsync(session.CustomerId);
 
 			bool hasActiveSub = false;