# Crussell

Nail salon booking platform — Go 1.26.5 backend + SvelteKit 5 SPA + PostgreSQL 17 + Docker. Built for a UK sole-trader nail artist. UK-only (Cloudflare geo-block), UK phone format. All timestamps UTC-normalised — the backend's `clock.Now()` returns UTC, the DB connection uses `timezone = "UTC"`, and the frontend converts between UTC and wall-clock time client-side. Single-employee business.

## Features

**Booking**: Self-service (customer), walk-in (admin), call-in (admin). Slot reservations prevent double-booking (4 TTL types). **Self-blocking prevention**: `excludeUserID` parameter filters a user's own `RESERVATION` entries from time blocker overlap checks, allowing re-reservation and booking at overlapping slots. **Explicit cancellation**: `DELETE /api/bookings/reserve` releases a user reservation; `DELETE /api/admin/bookings/reserve` releases an admin walk-in/call-in reservation. **Background cleanup**: Centralised cron scheduler (`backend/internal/jobs/`) runs 20 maintenance jobs: reservation/deposit cleanup every 5min, hourly campaign transitions, daily unpaid-booking notifications, GDPR anonymization, financial aggregation, and token/code cleanup. Guest accounts with GDPR-compliant anonymization (including `RESERVATION:edit_request:%` scrubbing). Service eligibility based on age + patch test validity. Overlap checks use `FOR UPDATE` row locks inside transactions. Closing-hours validation extracted into a reusable `closing_time` helper.

**Payments**: Square Terminal (in-person) + Web Payments SDK (online). Cash with change calculation. Gift cards (12-digit code or account balance). Saved cards for faster checkout. Tips on completed bookings. Refunds with notice-period tiers and deposit protection (72h/24h thresholds). All payment types: deposit, full, partial, balance, tip. Payment >20% of total promotes `pending_release` bookings back to `confirmed`. Deposit paid is computed from payments on-the-fly. The first 50% of each payment is always carved out as deposit (via `buildSplitRecords`); any overflow beyond the booking total becomes a tip. A PostgreSQL `pg_advisory_lock` serializes payment attempts per-booking to prevent two-tab double-payment races. Gift card purchases now insert a pending payment record with VAT before calling Square — the DB transaction commits first, so Square failures leave a retryable pending record.

**Gift Cards**: Multi-method purchase (cash, card machine, online card, giveaway). Inventory cards for stock management. 24-month rolling expiry. Idle account cleanup (2yr/5yr thresholds). Expired balance recovery with admin audit trail. Transaction audit log. Idempotency keys for purchases.

**Scheduling**: Default weekly hours, holiday/exceptional groups, time blockers (one-off + recurring with cron). Lunch protection. Late-night lock (22:00–11:00). Admin schedule page (Google Calendar-style week view).

**Custom Services**: One-off or special-request services not in the permanent catalog. Admin management with create, edit, promote to permanent service (migrates booking references), and delete. Full CRUD API with search, popular sorting, and pagination. Can be added to any booking alongside regular services.

**Admin**: Today page with interactive calendar grid. Booking management (create, edit, reschedule, approve, cancel). User management with customer relationship data (spend, visits, top services). Custom services (one-off services with create/edit/promote/delete). Discount campaigns (time-based and milestone). Time blocker CRUD. Portfolio image upload with tag management. Gift card management. Business settings (VAT, gift card config). Notification queue with priority ordering.

**Loyalty & Discounts**: 1 stamp per paid appointment (max 1/day). 10 stamps → 10% off via opt-in checkbox at payment or till. Stamps refunded on cancellation. Campaigns auto-apply at both payment and completion: time-based, per-user milestone, global milestone (in-person only), anniversary. All discounts stack additively against original total. Discount payment records excluded from refund calculations.

**Compliance**: GDPR Article 15 data export (async, 12h cache, 21-section JSON + PDF — excludes verification codes as authentication tokens). Account deletion with external system scrubbing (S3, Square). Guest PII anonymized 6 months post-appointment. UK financial data retention (7 years). Gift card SPV/MPV VAT treatment configurable.

**Frontend**: Portfolio gallery with fuzzy tag search (relevance-sorted) and exact category filters (date-sorted), multi-format images (AVIF/WebP/JPEG/JXL with WASM client-side encoding), cursor-based pagination. MapLibre GL map on contact page. PhoneInput component with UK validation. CharCounter for long notes.

**Infrastructure**: Docker Compose (postgres, backend, sabredav, nginx). Dev mock for Square payments (`//go:build dev`). RustFS dev storage, Cloudflare R2 for prod. SabreDAV CardDAV sync for profile photos.

**Middleware**: `JsonContentType` sets `Content-Type: application/json` globally, replacing ~80+ individual `w.Header().Set()` calls. `RespondJSON`/`RespondError` helpers standardise API response format. Progressive rate limiting (dual-window) on login/register with account lockout.

## Limitations

- **Single employee** — no multi-staff scheduling, no team management
- **No email/SMS** — SMTP integration not wired; booking reminders, password resets, and notifications are UI-only
- **No production S3/R2** — prod storage stubs return "not implemented"
- **No social auth** — OAuth providers (Google, Microsoft, Facebook) not registered
- **No dark mode, no PWA, no recurring bookings, no CSV export**
- **Password reset flow exists backend-only — no frontend link**
- **No error tracking/monitoring** — Sentry not configured

## Prerequisites

| Tool | Version |
|------|---------|
| Docker & Docker Compose | >= 20.10 |
| Go | >= 1.22 |
| Node | >= 18 (npm) |
| tmux | >= 3.0 |

## Getting Started

```bash
cp .env.example .env
# Edit .env — set POSTGRES_*, JWT_SECRET_KEY
docker compose up --build -d
```

| Service | URL |
|---------|-----|
| Frontend | http://localhost |
| API | http://localhost/api |
| SabreDAV | http://localhost/dav |

### Local dev (tmux)

```bash
./local-dev-2.sh
```

Launches 4-pane tmux session: psql console, Go dev server, Svelte dev server, Rustfs logs. Seeds 20 users, 12 services, 43 bookings, guest accounts, time blockers, exceptional hours.

Default logins (password: `password`):
- Admin: `admin@example.com`
- User: `user@example.com`

## Building & Testing

```bash
cd backend && go build -o bin/backend ./main.go
cd frontend && npm ci && npm run build
cd backend && go test -tags "test,dev" -count=1 -parallel 8 ./...   # ~1,642 tests passed (~13s)
cd backend && go test -tags "test,dev" -count=1 -race -timeout 480s ./...  # race detector (all packages, ~4min)
cd backend && go test -tags "test,dev" -count=10 -parallel 8 ./...  # thorough verification (~2-3min)
```

### Pre-commit hooks

`.githooks/pre-commit` runs on every commit (configured via `git config core.hooksPath .githooks`):
- **Frontend**: `prettier --write` auto-format, then `eslint` all files
- **Backend** (only if `backend/` changed): `go vet`, `golangci-lint` (3m timeout), `staticcheck`, `gosec`, `go mod tidy` check
- **Global**: `gitleaks` secret scan (skips gracefully if not installed)

To bypass: `git commit --no-verify`.

### CI caching

CI caches Go modules (`~/go/pkg/mod`) and npm dependencies (`~/.npm`, `node_modules`) via `actions/cache` — keyed on `go.sum` and `package-lock.json` respectively. Cache is served by Gitea's built-in cache server at `git.popertots.com`. First run downloads everything (~3m35s), subsequent runs restore from cache in seconds.

## Full Documentation

Detailed architecture, schema, admin workflows, user journeys, and backlog in [obsidian/Crussell/](obsidian/Crussell/).
