🦺 Prevent subscribing twice to same thing

.vscode/settings.json

@@ -9,8 +9,5 @@
 	},
 	"[css]": {
 		"editor.defaultFormatter": "vscode.css-language-features"
-	},
-	"[typescript]": {
-		"editor.defaultFormatter": "rvest.vs-code-prettier-eslint"
 	}
 }

src/lib/server/runtime-config.ts

@@ -4,7 +4,7 @@ import { collections } from './database';
 const defaultConfig = {
 	BTC_EUR: 30_000,
 	orderNumber: 0,
-	subscriptionDuration: "month" as "month" | "day" | "hour",
+	subscriptionDuration: 'month' as 'month' | 'day' | 'hour',
 	subscriptionReminderSeconds: 24 * 60 * 60,
 
 	checkoutButtonOnProductPage: true,

src/lib/types/Order.ts

@@ -2,7 +2,6 @@ import type { Product } from './Product';
 import type { Currency } from './Currency';
 import type { CountryAlpha3 } from './Country';
 import type { Timestamps } from './Timestamps';
-import type { ObjectId } from 'mongodb';
 
 export interface Order extends Timestamps {
 	/**
@@ -16,7 +15,6 @@ export interface Order extends Timestamps {
 	items: Array<{
 		product: Product;
 		quantity: number;
-		subscriptionId?: ObjectId;
 	}>;
 
 	shippingAddress?: {

src/lib/types/PaidSubscription.ts

@@ -11,6 +11,6 @@ export interface PaidSubscription extends Timestamps {
 	npub: string;
 	productId: string;
 
-	paidUntil?: Date;
+	paidUntil: Date;
 	lastRemindedAt?: Date;
 }

src/routes/admin/config/+page.server.ts

@@ -21,8 +21,12 @@ export const actions = {
 			.object({
 				checkoutButtonOnProductPage: z.boolean({ coerce: true }),
 				discovery: z.boolean({ coerce: true }),
-				subscriptionDuration: z.enum(["month", "day", "hour"]),
-				subscriptionReminderSeconds: z.number({coerce: true}).int().min(0).max(24 * 60 * 60 * 7)
+				subscriptionDuration: z.enum(['month', 'day', 'hour']),
+				subscriptionReminderSeconds: z
+					.number({ coerce: true })
+					.int()
+					.min(0)
+					.max(24 * 60 * 60 * 7)
 			})
 			.parse({
 				checkoutButtonOnProductPage: formData.get('checkoutButtonOnProductPage'),

src/routes/checkout/+page.server.ts

@@ -4,11 +4,12 @@ import { lndCreateInvoice } from '$lib/server/lightning.js';
 import { paymentMethods } from '$lib/server/payment-methods.js';
 import { COUNTRY_ALPHA3S } from '$lib/types/Country';
 import { error, redirect } from '@sveltejs/kit';
-import { addHours, differenceInSeconds } from 'date-fns';
+import { addHours, differenceInSeconds, subSeconds } from 'date-fns';
 import { z } from 'zod';
 import { bech32 } from 'bech32';
 import { ORIGIN } from '$env/static/private';
 import { toSatoshis } from '$lib/utils/toSatoshis.js';
+import { runtimeConfig } from '$lib/server/runtime-config.js';
 
 export function load() {
 	return {
@@ -104,6 +105,49 @@ export const actions = {
 
 		const orderId = crypto.randomUUID();
 
+		const subscriptions = cart.items.filter((item) => byId[item.productId].type === 'subscription');
+
+		for (const subscription of subscriptions) {
+			const product = byId[subscription.productId];
+
+			if (subscription.quantity > 1) {
+				throw error(
+					400,
+					'Cannot order more than one of a subscription at a time for product: ' + product.name
+				);
+			}
+
+			const existingSubscription = await collections.paidSubscriptions.findOne({
+				npub: npubAddress,
+				productId: product._id
+			});
+
+			if (existingSubscription) {
+				if (
+					subSeconds(existingSubscription.paidUntil, runtimeConfig.subscriptionReminderSeconds) >
+					new Date()
+				) {
+					throw error(
+						400,
+						'You already have an active subscription for this product: ' + product.name
+					);
+				}
+			}
+
+			if (
+				await collections.orders.countDocuments(
+					{
+						'notifications.paymentStatus.npub': npubAddress,
+						'items.product._id': product._id,
+						'payment.status': 'pending'
+					},
+					{ limit: 1 }
+				)
+			) {
+				throw error(400, 'You already have a pending order for this product: ' + product.name);
+			}
+		}
+
 		await withTransaction(async (session) => {
 			const res = await collections.runtimeConfig.findOneAndUpdate(
 				{ _id: 'orderNumber' },