# Architecture

## Shape: Vue SPA ⇄ REST API ⇄ fat Laravel Services

The frontend is a **Vue 3 single-page app** (`resources/js/`). It talks to the
backend exclusively over a **REST API** (`routes/api.php` →
`app/Http/Controllers/Api/`). Controllers stay thin; all business logic lives in
**Service classes** (`app/Services/`). Blade is reduced to a one-line SPA shell,
server-rendered legal pages, transactional emails, and the Filament admin panel.

```
Browser
  └── Vue SPA (resources/js, mounted on #app via app.blade.php)
        └── axios (resources/js/axios.js — baseURL '/api', cookie + XSRF auth)
              └── REST API (routes/api.php → Http/Controllers/Api/*)
                    └── Services (app/Services/*)   ← all business logic
                          └── Models / Jobs / Events / Notifications
```

## Core principle: fat Services, thin everything else

All business logic lives in Service classes. API controllers, console commands,
jobs, listeners, and Filament resources are thin orchestrators — they call
Services and return results. Never put domain logic in a controller or a Vue
component.

## Directory structure (actual)

```
app/
├── Console/Commands/   # Scheduler: PollFuelPrices, FetchOilPrices, BackfillOilPrices,
│                       #   RunLlmOverlay, EvaluateVolatilityRegime, ResolveForecastOutcomes,
│                       #   ArchiveOldPricesCommand, ImportBeisFuelPrices, ImportPostcodes
├── Http/
│   ├── Controllers/Api/   # AuthController, StationController, StatsController, UserController
│   ├── Controllers/       # BillingController (Stripe Checkout/Portal redirects)
│   ├── Middleware/        # VerifyApiKey (API-key gate), RequiresFeature (tier gate)
│   ├── Requests/          # Form requests
│   └── Resources/Api/     # StationResource (API output shaping)
├── Actions/Fortify/    # Fortify auth actions (CreateNewUser, …)
├── Services/           # ALL business logic — see below
├── Models/             # Eloquent models
├── Notifications/      # FuelPriceAlert + custom Channels (OneSignal, Vonage WA/SMS)
├── Jobs/               # DispatchUserNotificationJob, PollFuelPricesJob,
│                       #   SendScheduledWhatsAppJob, SendPaymentFailedReminderJob
├── Events/             # PricesUpdatedEvent
├── Listeners/          # HandleStripeWebhook (Cashier WebhookReceived)
├── Filament/           # Admin panel (Resources, Widgets) + Providers/Filament
├── Enums/              # FuelType, PlanTier, …
└── Livewire/Actions/   # Logout only — Livewire is otherwise vestigial

app/Services/
├── FuelPriceService.php       # Fuel Finder API polling + storage
├── StationTaggingService.php  # Supermarket brand detection
├── PostcodeService.php        # postcode/outcode/place → lat/lng (+ LocationResult DTO)
├── PlanFeatures.php           # Single source of tier-entitlement truth (see tiers.md)
├── HaversineQuery.php         # Distance SQL helper
├── ApiLogger.php              # Wraps outbound HTTP, logs to api_logs
├── StationSearch/             # StationSearchService (+ SearchCriteria, SearchResult DTOs)
├── BrentPriceSources/         # FRED + EIA Brent sources (+ BrentPriceFetcher)
└── Forecasting/               # Weekly forecast subsystem — WeeklyForecastService,
                               #   LlmOverlayService, BacktestRunner, OutcomeResolver,
                               #   VolatilityRegimeService, feature/leak tooling, …

resources/
├── js/                 # Vue 3 SPA — see .claude/rules/frontend.md
└── views/
    ├── app.blade.php   # SPA shell (mounts #app)
    ├── legal/          # Server-rendered legal pages
    ├── emails/         # Mailable templates
    └── livewire/auth/  # Starter-kit Volt auth screens (left untouched)

routes/
├── web.php             # SPA shell + catch-all, legal pages, billing redirects, server logout
└── api.php             # REST API consumed by the SPA (see below)
```

> **Stale service names elsewhere.** Domain rule files (`scoring.md`,
> `prediction.md`, `notifications.md`) still name services that have since been
> refactored away — e.g. `AlertScoringService`, `OilPriceService`,
> `NationalFuelPredictionService`, `NotificationDispatchService`,
> `SubscriptionService`. Those concerns now live under `Services/Forecasting/`,
> `Services/StationSearch/`, and `PlanFeatures`. Always verify a service name
> against `app/Services/` before trusting it from those files.

## Service class conventions

- Constructor injection only — no facade usage inside Services
- Each Service has one responsibility — do not merge concerns
- Return typed DTOs or Eloquent collections — never raw arrays from Services
- Services never dispatch jobs directly — that's the controller/command/listener's job

## The REST API

`routes/api.php` is the SPA's backend. Three access tiers:

- **Public** (no auth): `POST /api/auth/register`, `POST /api/auth/login`,
  `GET /api/auth/me`, `GET /api/fuel-types`, `GET /api/stats/live`
- **API-key** (`VerifyApiKey` + `throttle:60,1`): `GET /api/stations`,
  `GET /api/stats/searches`
- **Sanctum** (`auth:sanctum`): `POST /api/auth/logout`, `/api/user/*`
  (preferences, saved stations, profile, password, delete account)

Conventions:

- Shape responses with API Resources (`app/Http/Resources/Api/`), never raw arrays.
- The fuel **prediction is embedded in the `/api/stations` response** under the
  `prediction` key — there is no standalone prediction endpoint (see `prediction.md`).
- Tier-gate routes with the `feature` middleware (`RequiresFeature`); never
  inline entitlement checks (see `tiers.md`).
- Auth is cookie/session via Sanctum SPA mode (axios sends XSRF + credentials);
  the API-key gate protects the expensive station search from scraping.

## Frontend

The Vue SPA is documented in `.claude/rules/frontend.md`. Do **not** build new
Livewire components — Livewire/Flux remain only for the starter-kit auth screens
and the `Logout` action.