Trainer Tally

Sessions, packages, monthly bills and studio rent for personal trainers, counted from Google Calendar.

One codebase, two homes:

	claude.ai version (today)	Hosted version (launch)
Runs in	a Claude artifact	your own domain on Vercel
Sign-in	the viewer's Claude account	Continue with Google
Calendar	the viewer's Claude Google Calendar connector	Google Calendar API (read-only)
Data	artifact database, private per viewer	Supabase, private per trainer (row-level security)
Built from	src/app.js + src/adapter-claude.js	src/app.js + src/adapter-hosted.js

src/app.js holds all the logic and screens. Each adapter only answers "where is the data" and "how do I read the calendar". Change the app once and both versions get it.

src/
  app.js              engine + UI (shared)
  styles.css          design (shared; cream light + dark)
  shell.html          page frame (shared)
  adapter-claude.js   claude.ai storage + calendar
  adapter-hosted.js   Supabase storage + /api/calendar
api/
  calendar.js         Google Calendar proxy (read-only)
  auth/store-token.js keeps the Google refresh token server-side
  billing/*.js        Stripe checkout, portal, webhook
supabase/schema.sql   tables + row-level security
scripts/build-artifact.mjs   builds the single-file claude.ai page
public/privacy.html   privacy policy draft (needed for Google review)

Update the claude.ai version

npm run build:artifact     # writes dist-artifact/index.html

Then ask Claude to republish that file to the existing Trainer Tally link. Data paths never change, so everyone's data carries over.

Launch the hosted version

About an hour of clicking, in this order.

1. Supabase (database + login)

1. Create a project at supabase.com.
2. SQL Editor → paste supabase/schema.sql → Run.
3. Project Settings → API: copy the Project URL, anon public key and service_role key.

2. Google Cloud (calendar access)

1. console.cloud.google.com → new project "Trainer Tally".
2. APIs & Services → Library → enable Google Calendar API.
3. OAuth consent screen → External. App name, support email, logo, your domain, and the privacy URL (https://YOUR-DOMAIN/privacy.html). Scopes: add .../auth/calendar.readonly. Under Test users, add Tatjana and anyone else testing (up to 100).
4. Credentials → Create OAuth client ID → Web application. Authorized redirect URI: https://YOUR-PROJECT.supabase.co/auth/v1/callback
5. Copy the Client ID and Client secret.
6. Back in Supabase: Authentication → Providers → Google → paste them → enable. Authentication → URL Configuration → Site URL https://YOUR-DOMAIN, and add http://localhost:3000 for local testing.

3. Vercel (hosting)

1. Push this folder to a GitHub repo, then import it at vercel.com.
2. Settings → Environment Variables: add everything in .env.example.
3. Deploy. Add your domain under Settings → Domains, then set APP_URL to it.

4. Stripe ($3/month), when you're ready to charge

Do all of this in a sandbox first, then repeat in live mode.

1. Product catalog → create Trainer Tally, recurring price $3.00 / month. Copy the price ID (price_...).
2. Developers → API keys → copy the secret key into Vercel as STRIPE_SECRET_KEY (never paste it into chat or commit it).
3. Developers → Webhooks → Add endpoint https://YOUR-DOMAIN/api/billing/webhook, events: checkout.session.completed, customer.subscription.created, customer.subscription.updated, customer.subscription.deleted, customer.subscription.paused, customer.subscription.resumed, invoice.paid, invoice.payment_failed. Copy the signing secret into STRIPE_WEBHOOK_SECRET.
4. Settings → Billing → Customer portal: turn on invoice history, update payment method, and cancel (at period end).
5. Settings → Billing → Subscriptions and emails: turn on Smart Retries, emails for failed payments and expiring cards, and "Email finalized invoices / successful payments" so subscribers get receipts.
6. Optional: turn on Stripe Tax and set STRIPE_AUTOMATIC_TAX=true (Massachusetts taxes SaaS; check with your accountant).
7. Set VITE_BILLING_ENABLED=true. When the trial should start counting, set REQUIRE_SUBSCRIPTION=true; new sign-ups get TRIAL_DAYS free.

How access works: the webhook re-reads each subscription from Stripe and stores access_until (end of the paid period + 2 days). active, trialing and past_due (while Stripe retries the card) keep the app unlocked; canceled, unpaid and expired checkouts lock it once access_until passes. A subscriber who taps Subscribe again is sent to the portal, not a second subscription.

Test cards: 4242 4242 4242 4242 succeeds, 4000 0000 0000 0341 fails on renewal. Any future date and any CVC.

5. Google verification (before strangers can sign in)

While the consent screen is in Testing, only listed test users can sign in. To open it to everyone, click Publish app and submit for verification. calendar.readonly is a sensitive scope: Google asks for the privacy policy, a short screen recording of the sign-in and how calendar data is used, and domain verification. Typical turnaround is a few weeks. No paid security audit is needed for this scope.

Studio side (/studio.html)

For studio owners who rent space to trainers. Run supabase/studio.sql once after schema.sql.

This is the beginning of the README. Read the rest at the original. Read the full README ↗