fix(billing): allow switching billing interval during trial

Switching plan mid-trial always forced the monthly price and there was no
way to move to annual. Preserve trial_end on the Stripe update so changing
the interval does not reset the billing cycle and end the trial early.

apps/dokploy/components/dashboard/settings/billing/show-billing.tsx

@@ -111,14 +111,20 @@ export const ShowBilling = () => {
 	const [trialTier, setTrialTier] = useState<"hobby" | "startup" | null>(null);
 	const [switchingTrial, setSwitchingTrial] = useState(false);
 
-	const handleSwitchTrialPlan = async (tier: "hobby" | "startup") => {
-		const planName = tier === "startup" ? "Startup" : "Hobby";
+	const handleSwitchTrialPlan = async (
+		tier: "hobby" | "startup",
+		isAnnualPlan: boolean,
+		label?: string,
+	) => {
+		const planName =
+			label ??
+			`${tier === "startup" ? "Startup" : "Hobby"} ${isAnnualPlan ? "annual" : "monthly"}`;
 
 		const switchPlan = async () => {
 			await upgradeSubscription({
 				tier,
 				serverQuantity: tier === "startup" ? STARTUP_SERVERS_INCLUDED : 1,
-				isAnnual: false,
+				isAnnual: isAnnualPlan,
 			});
 			await new Promise((resolve) => setTimeout(resolve, 3000));
 			await Promise.all([
@@ -133,7 +139,7 @@ export const ShowBilling = () => {
 		await toast
 			.promise(switchPlan(), {
 				loading: `Switching to ${planName}...`,
-				success: `Your trial is now on the ${planName} plan`,
+				success: `Your trial is now on ${planName}`,
 				error: (error) =>
 					error instanceof Error ? error.message : "Error switching plan",
 			})
@@ -336,6 +342,11 @@ export const ShowBilling = () => {
 													<Badge className="capitalize" variant="secondary">
 														{billingStatus.plan ?? "Trial"}
 													</Badge>
+													{billingStatus.plan && (
+														<Badge variant="outline">
+															{billingStatus.isAnnual ? "Annual" : "Monthly"}
+														</Badge>
+													)}
 												</div>
 												<span className="text-sm text-muted-foreground">
 													{billingStatus.isOnTrial
@@ -356,23 +367,45 @@ export const ShowBilling = () => {
 											<div className="flex flex-wrap items-center gap-2">
 												{billingStatus.isOnTrial &&
 													useNewPricing &&
-													billingStatus.plan && (
-														<Button
-															size="sm"
-															variant="outline"
-															isLoading={switchingTrial}
-															onClick={() =>
-																handleSwitchTrialPlan(
-																	billingStatus.plan === "startup"
-																		? "hobby"
-																		: "startup",
-																)
-															}
-														>
-															{billingStatus.plan === "startup"
-																? "Switch to Hobby"
-																: "Switch to Startup"}
-														</Button>
+													billingStatus.plan &&
+													billingStatus.plan !== "legacy" && (
+														<>
+															<Button
+																size="sm"
+																variant="outline"
+																isLoading={switchingTrial}
+																onClick={() =>
+																	handleSwitchTrialPlan(
+																		billingStatus.plan === "startup"
+																			? "hobby"
+																			: "startup",
+																		billingStatus.isAnnual,
+																	)
+																}
+															>
+																{billingStatus.plan === "startup"
+																	? "Switch to Hobby"
+																	: "Switch to Startup"}
+															</Button>
+															<Button
+																size="sm"
+																variant="outline"
+																isLoading={switchingTrial}
+																onClick={() =>
+																	handleSwitchTrialPlan(
+																		billingStatus.plan as "hobby" | "startup",
+																		!billingStatus.isAnnual,
+																		billingStatus.isAnnual
+																			? "monthly billing"
+																			: "annual billing",
+																	)
+																}
+															>
+																{billingStatus.isAnnual
+																	? "Switch to monthly"
+																	: "Switch to annual"}
+															</Button>
+														</>
 													)}
 												<Button
 													size="sm"

apps/dokploy/server/api/routers/stripe.ts

@@ -388,6 +388,9 @@ export const stripeRouter = createTRPCRouter({
 			await stripe.subscriptions.update(owner.stripeSubscriptionId, {
 				items: updateItems,
 				proration_behavior: isTrialing ? "none" : "create_prorations",
+				...(isTrialing && subscription.trial_end
+					? { trial_end: subscription.trial_end }
+					: {}),
 			});
 
 			return { ok: true };

apps/dokploy/server/utils/billing.ts

@@ -92,6 +92,7 @@ export interface BillingStatus {
 	hasUsedTrial: boolean;
 	hasActiveAccess: boolean;
 	hasPaymentMethod: boolean;
+	isAnnual: boolean;
 }
 
 export const getBillingStatus = async (
@@ -106,6 +107,7 @@ export const getBillingStatus = async (
 			hasUsedTrial: false,
 			hasActiveAccess: true,
 			hasPaymentMethod: true,
+			isAnnual: false,
 		};
 	}
 
@@ -119,6 +121,7 @@ export const getBillingStatus = async (
 			hasUsedTrial: false,
 			hasActiveAccess: false,
 			hasPaymentMethod: false,
+			isAnnual: false,
 		};
 	}
 
@@ -146,6 +149,9 @@ export const getBillingStatus = async (
 	const hasPaymentMethod =
 		!!currentSub?.default_payment_method ||
 		!!customer?.invoice_settings?.default_payment_method;
+	const isAnnual =
+		(currentSub?.items.data[0]?.price as Stripe.Price | undefined)?.recurring
+			?.interval === "year";
 	const trialEndsAt = trialingSub?.trial_end
 		? new Date(trialingSub.trial_end * 1000)
 		: null;
@@ -164,5 +170,6 @@ export const getBillingStatus = async (
 		hasPaymentMethod,
 		hasUsedTrial: subscriptions.data.length > 0,
 		hasActiveAccess: plan !== null || !!trialingSub,
+		isAnnual,
 	};
 };