feat: add multi subscription support (#734)

## Description

Previously we assumed that there can only be 1 subscription per user.
However, that will soon no longer the case with the introduction of the
Teams subscription.

This PR will apply the required migrations to support multiple
subscriptions.

## Changes Made

- Updated the Prisma schema to allow for multiple `Subscriptions` per
`User`
- Added a Stripe `customerId` field to the `User` model
- Updated relevant billing sections to support multiple subscriptions

## Testing Performed

- Tested running the Prisma migration on a demo database created on the
main branch

Will require a lot of additional testing.

## Checklist

- [ ] I have tested these changes locally and they work as expected.
- [ ] I have added/updated tests that prove the effectiveness of these
changes.
- [X] I have followed the project's coding style guidelines.

## Additional Notes

Added the following custom SQL statement to the migration:

> DELETE FROM "Subscription" WHERE "planId" IS NULL OR "priceId" IS
NULL;

Prior to deployment this will require changes to Stripe products:
- Adding `type` meta attribute

---------

Co-authored-by: Lucas Smith <me@lucasjamessmith.me>

packages/lib/server-only/admin/get-users-stats.ts

@@ -9,7 +9,9 @@ export const getUsersWithSubscriptionsCount = async () => {
   return await prisma.user.count({
     where: {
       Subscription: {
-        status: SubscriptionStatus.ACTIVE,
+        some: {
+          status: SubscriptionStatus.ACTIVE,
+        },
       },
     },
   });

packages/lib/server-only/subscription/get-subscription-by-user-id.ts

@@ -1,15 +0,0 @@
-'use server';
-
-import { prisma } from '@documenso/prisma';
-
-export type GetSubscriptionByUserIdOptions = {
-  userId: number;
-};
-
-export const getSubscriptionByUserId = async ({ userId }: GetSubscriptionByUserIdOptions) => {
-  return await prisma.subscription.findFirst({
-    where: {
-      userId,
-    },
-  });
-};

packages/lib/server-only/subscription/get-subscriptions-by-user-id.ts

@@ -0,0 +1,15 @@
+'use server';
+
+import { prisma } from '@documenso/prisma';
+
+export type GetSubscriptionsByUserIdOptions = {
+  userId: number;
+};
+
+export const getSubscriptionsByUserId = async ({ userId }: GetSubscriptionsByUserIdOptions) => {
+  return await prisma.subscription.findMany({
+    where: {
+      userId,
+    },
+  });
+};

packages/lib/server-only/user/create-user.ts

@@ -1,9 +1,11 @@
 import { hash } from 'bcrypt';
 
+import { getStripeCustomerByUser } from '@documenso/ee/server-only/stripe/get-customer';
 import { prisma } from '@documenso/prisma';
 import { IdentityProvider } from '@documenso/prisma/client';
 
 import { SALT_ROUNDS } from '../../constants/auth';
+import { getFlag } from '../../universal/get-feature-flag';
 
 export interface CreateUserOptions {
   name: string;
@@ -13,6 +15,8 @@ export interface CreateUserOptions {
 }
 
 export const createUser = async ({ name, email, password, signature }: CreateUserOptions) => {
+  const isBillingEnabled = await getFlag('app_billing');
+
   const hashedPassword = await hash(password, SALT_ROUNDS);
 
   const userExists = await prisma.user.findFirst({
@@ -25,7 +29,7 @@ export const createUser = async ({ name, email, password, signature }: CreateUse
     throw new Error('User already exists');
   }
 
-  return await prisma.user.create({
+  let user = await prisma.user.create({
     data: {
       name,
       email: email.toLowerCase(),
@@ -34,4 +38,15 @@ export const createUser = async ({ name, email, password, signature }: CreateUse
       identityProvider: IdentityProvider.DOCUMENSO,
     },
   });
+
+  if (isBillingEnabled) {
+    try {
+      const stripeSession = await getStripeCustomerByUser(user);
+      user = stripeSession.user;
+    } catch (e) {
+      console.error(e);
+    }
+  }
+
+  return user;
 };