Note Calc

Note Calc is a collaborative Python notepad + calculator built for fast technical thinking.
It combines a code editor, inline computation, and real-time sharing in a single web app.

Why this project

Most tools force a tradeoff between "note-taking" and "calculation". Note Calc is built to do both:

• Write plain-English context and Python logic in one place
• Execute and inspect outputs without leaving the editor
• Share, review, and iterate with collaborators in real time

Core capabilities

• Guest mode on / with an instant demo note (no login required)
• Python execution in-browser via Pyodide
• Inline line-level calculation results
• Authenticated note persistence in Supabase
• Auto-save workflow for authenticated notes
• Rich note metadata (tags, pin, important flag, related date)
• Smart note discovery (filtering, sorting, and search ranking)
• Real-time collaborative editing + live collaborator presence
• Share controls:
  • private notes
  • link-based read access
  • link-based edit access
  • email-based read/edit access
• Role-aware access model (owner, shared_read, shared_edit, public_read, public_edit)

Quality and automation

• Unit/integration test suite with Vitest + Testing Library for core modules:
  • auth flows and redirect safety
  • notes/profile API adapters and hooks
  • editor preferences store
  • collaboration session behavior
  • Pyodide runner/intellisense integration points
• Browser-level Playwright coverage for notepad guest workflows:
  • /notepad loads editor shell and key controls
  • guest draft persistence behavior in local storage
• CI workflow in .github/workflows/ci.yml enforces:
  • lint
  • coverage tests
  • production build
  • notepad browser tests

Product routes

• / guest editor + app entry
• /login email OTP and optional OAuth sign-in
• /auth/callback auth token/code exchange
• /notepad/:noteId owned or shared note by ID
• /shared/:shareToken token-based shared note access
• /about product overview

Tech stack

• Frontend: React 19, TypeScript, Vite
• Routing/Data: TanStack Router, TanStack Query
• UI: Mantine
• Editor: Monaco
• Python runtime: Pyodide (web worker)
• Collaboration: Yjs + Supabase Realtime channel sync
• Backend: Supabase (Postgres, Auth, RLS, RPC)
• Deploy target: Cloudflare Pages

Security and data model

Supabase migrations in supabase/migrations/ define:

• notes and note_shares tables
• row-level security (RLS) policies for owner/shared/public access
• RPC-based access functions for:
  • guest draft import
  • listing accessible notes
  • secure note reads by ID or share token
  • secure note updates with permission checks
  • share management and public access control

Local development

1. Prerequisites

• Node.js 20+
• pnpm
• A Supabase project

2. Install dependencies

pnpm install

3. Configure environment

Create a local .env (or copy from .env.example) and set:

VITE_SUPABASE_URL=...
VITE_SUPABASE_ANON_KEY=...
VITE_SUPABASE_OAUTH_PROVIDERS=google,github # optional, comma-separated

4. Run database migrations

Run SQL files in supabase/migrations/ in chronological order:

1. 20260210_notes_backend.sql
2. 20260213_fix_note_shares_rls_recursion.sql
3. 20260214_allow_anon_link_edit.sql
4. 20260217_optimize_rls_and_fk_indexes.sql

5. Configure Supabase Auth

In Supabase Auth URL settings:

• Local site URL: http://localhost:5173
• Local redirect URL: http://localhost:5173/auth/callback
• Production site URL: your deployed domain
• Production redirect URL: https://<your-domain>/auth/callback

6. Start the app

pnpm dev

7. Browser test prerequisites (Playwright)

Install Playwright browser binaries:

pnpm exec playwright install chromium

On Linux CI/containers, install system dependencies when needed:

pnpm exec playwright install --with-deps chromium

Scripts

• pnpm dev start local dev server
• pnpm build type-check + production build
• pnpm lint run ESLint
• pnpm test run unit/integration tests
• pnpm test:watch run tests in watch mode
• pnpm test:coverage run tests with coverage reports (coverage/)
• pnpm test:e2e run browser tests for notepad flows (Playwright)
• pnpm test:e2e:headed run browser tests with visible browser
• pnpm check run lint + coverage + production build
• pnpm preview preview production build locally
• pnpm pages:deploy build and deploy to Cloudflare Pages via Wrangler

Deployment notes (Cloudflare Pages)

• Ensure VITE_SUPABASE_URL and VITE_SUPABASE_ANON_KEY are set in Pages environment variables
• Keep SPA fallback enabled so routes like /notepad/:id and /shared/:token resolve to index.html
• Keep Supabase redirect URLs in sync with deployed domains

License

This repository is licensed under the Note Calc Non-Commercial License v1.0 (LICENSE).

• Non-commercial use, modification, and redistribution are allowed
• Commercial/profit-generating use requires explicit written permission from the copyright holder