refactor(stores): tighten chat and payment boundaries

src/stores/payment/payment-machine.helpers.ts

@@ -41,6 +41,45 @@ export function getDefaultPlanId(plans: readonly PaymentPlan[]): string {
   );
 }
 
+export function hydratePlansState(
+  plans: PaymentPlan[],
+  selectedPlanId: string,
+): Pick<PaymentState, "plans" | "selectedPlanId" | "autoRenew" | "errorMessage"> {
+  const nextSelectedPlanId = selectedPlanId || getDefaultPlanId(plans);
+  return {
+    plans,
+    selectedPlanId: nextSelectedPlanId,
+    autoRenew: defaultAutoRenewForPlan(nextSelectedPlanId, plans),
+    errorMessage: null,
+  };
+}
+
+export function refreshPlansState(
+  plans: PaymentPlan[],
+  selectedPlanId: string,
+): Pick<PaymentState, "plans" | "selectedPlanId" | "autoRenew" | "errorMessage"> {
+  const nextSelectedPlanId = plans.some((plan) => plan.planId === selectedPlanId)
+    ? selectedPlanId
+    : getDefaultPlanId(plans);
+  return {
+    plans,
+    selectedPlanId: nextSelectedPlanId,
+    autoRenew: defaultAutoRenewForPlan(nextSelectedPlanId, plans),
+    errorMessage: null,
+  };
+}
+
+export function selectPlanState(
+  planId: string,
+  plans: readonly PaymentPlan[],
+): Partial<PaymentState> {
+  return {
+    ...resetOrderState(),
+    selectedPlanId: planId,
+    autoRenew: defaultAutoRenewForPlan(planId, plans),
+  };
+}
+
 export function resetOrderState(): Partial<PaymentState> {
   return {
     currentOrderId: null,