collab: Check if the user has a payment method before upgrading to Zed Pro (#30310)

This PR adds a check for if the user has a payment method before
attempting to upgrade them to Zed Pro.

Release Notes:

- N/A

crates/collab/src/api/billing.rs

@@ -18,7 +18,8 @@ use stripe::{
     CreateBillingPortalSessionFlowDataSubscriptionUpdateConfirm,
     CreateBillingPortalSessionFlowDataSubscriptionUpdateConfirmItems,
     CreateBillingPortalSessionFlowDataType, CreateCustomer, Customer, CustomerId, EventObject,
-    EventType, Expandable, ListEvents, Subscription, SubscriptionId, SubscriptionStatus,
+    EventType, Expandable, ListEvents, PaymentMethod, Subscription, SubscriptionId,
+    SubscriptionStatus,
 };
 use util::{ResultExt, maybe};
 
@@ -445,6 +446,7 @@ struct ManageBillingSubscriptionBody {
     intent: ManageSubscriptionIntent,
     /// The ID of the subscription to manage.
     subscription_id: BillingSubscriptionId,
+    redirect_to: Option<String>,
 }
 
 #[derive(Debug, Serialize)]
@@ -542,6 +544,23 @@ async fn manage_billing_subscription(
                         .map_or(false, |price| price.id == zed_pro_price_id)
                 });
             if is_on_zed_pro_trial {
+                let payment_methods = PaymentMethod::list(
+                    &stripe_client,
+                    &stripe::ListPaymentMethods {
+                        customer: Some(stripe_subscription.customer.id()),
+                        ..Default::default()
+                    },
+                )
+                .await?;
+
+                let has_payment_method = !payment_methods.data.is_empty();
+                if !has_payment_method {
+                    return Err(Error::http(
+                        StatusCode::BAD_REQUEST,
+                        "missing payment method".into(),
+                    ));
+                }
+
                 // If the user is already on a Zed Pro trial and wants to upgrade to Pro, we just need to end their trial early.
                 Subscription::update(
                     &stripe_client,
@@ -596,7 +615,11 @@ async fn manage_billing_subscription(
             after_completion: Some(CreateBillingPortalSessionFlowDataAfterCompletion {
                 type_: stripe::CreateBillingPortalSessionFlowDataAfterCompletionType::Redirect,
                 redirect: Some(CreateBillingPortalSessionFlowDataAfterCompletionRedirect {
-                    return_url: format!("{}/account", app.config.zed_dot_dev_url()),
+                    return_url: format!(
+                        "{}{path}",
+                        app.config.zed_dot_dev_url(),
+                        path = body.redirect_to.unwrap_or_else(|| "/account".to_string())
+                    ),
                 }),
                 ..Default::default()
             }),