feat(payment): expand Stripe methods and checkout handoff

src/lib/navigation/external_entry.ts

@@ -4,8 +4,10 @@ import { AuthStorage } from "@/data/storage/auth/auth_storage";
 import { UserStorage } from "@/data/storage/user/user_storage";
 import type { PendingChatPromotionType } from "@/data/storage/navigation";
 import type { LoginStatus } from "@/data/schemas/auth";
+import type { CheckoutIntent } from "@/data/schemas/auth";
 import {
   DEFAULT_CHARACTER_SLUG,
+  getCharacterById,
   getCharacterBySlug,
 } from "@/data/constants/character";
 import { getCharacterRoutes, ROUTES } from "@/router/routes";
@@ -100,6 +102,30 @@ export function resolveExternalEntryDestination({
   return routes.chat;
 }
 
+export function resolveCheckoutIntentDestination(
+  intent: CheckoutIntent,
+): string {
+  const params = new URLSearchParams({ planId: intent.planId });
+
+  if (intent.recipientCharacterId) {
+    const character = getCharacterById(intent.recipientCharacterId);
+    const routes = getCharacterRoutes(
+      character?.slug ?? DEFAULT_CHARACTER_SLUG,
+    );
+    if (intent.chatActionId) params.set("chatActionId", intent.chatActionId);
+    params.set("payChannel", "stripe");
+    return `${routes.tip}?${params.toString()}`;
+  }
+
+  params.set("autoRenew", intent.autoRenew ? "1" : "0");
+  if (intent.commercialOfferId) {
+    params.set("commercialOfferId", intent.commercialOfferId);
+  }
+  if (intent.chatActionId) params.set("chatActionId", intent.chatActionId);
+  params.set("payChannel", "stripe");
+  return `${ROUTES.subscription}?${params.toString()}`;
+}
+
 export async function persistExternalEntryPayload({
   deviceId,
   asid,
@@ -138,6 +164,7 @@ function resolveTarget(
     return ROUTES.privateZone;
   }
   if (target === "topup") return ROUTES.subscription;
+  if (target === "checkout") return ROUTES.subscription;
 
   return null;
 }