# SummerCMS Technology Stack

## Philosophy

**Direct-style Scala 3 on JDK 21 virtual threads.** No monadic effect systems (no ZIO, no Cats Effect). Virtual threads make blocking IO cheap, so you write normal imperative-looking code that scales. This is the simplest possible modern Scala stack.

---

## Core Stack

| Layer | Technology | Why |
|-------|-----------|-----|
| **Language** | Scala 3.3+ LTS | VirtusLab maintains the compiler. Scala 3 has cleaner syntax, given/using for DI, extension methods, enums, union types |
| **Runtime** | JDK 21+ with Project Loom | Virtual threads = millions of lightweight threads, no async/callback hell |
| **HTTP Server** | Tapir + JDK HttpServer | Tapir gives type-safe endpoint definitions with auto-generated OpenAPI docs. JDK HttpServer with `Executors.newVirtualThreadPerTaskExecutor()` is the lightest possible server |
| **Concurrency** | Ox | Structured concurrency, Go-like channels, error supervision, retries, rate limiting. Built on virtual threads |
| **Database** | Magnum | Scala 3 native, typesafe SQL interpolator, auto-generated CRUD, no dependencies, works with any JDBC database |
| **Migrations** | Flyway | Industry standard, JVM-native, works with any JDBC database |

## Supporting Libraries

| Concern | Library | Notes |
|---------|---------|-------|
| **JSON** | uPickle or Circe | Serialization/deserialization for API + config |
| **Config** | Typesafe Config (HOCON) | Industry standard JVM config, supports YAML-like nesting, env var substitution |
| **Logging** | SLF4J + Logback | Standard JVM logging — used directly, no wrapper needed |
| **Caching** | Caffeine (in-memory) + Jedis/Lettuce (Redis) | Caffeine is the fastest JVM cache; Redis for distributed |
| **Hashing** | jBCrypt + JDK crypto | Password hashing + general encryption |
| **Email** | Jakarta Mail | Standard JVM email |
| **Admin Frontend** | Vue.js 3 + TypeScript | SPA admin panel consuming Tapir API |
| **OpenAPI codegen** | Tapir -> OpenAPI -> openapi-typescript | Auto-generated TS types for Vue frontend |
| **Template Engine** | Scalate (Mustache/SSP) or Twirl | Server-rendered public-facing themes |
| **CLI** | Decline or Scopt | Console command parsing for scaffolding |
| **Testing** | MUnit or ScalaTest + Tapir test utils | Unit + integration testing |
| **Build (project)** | sbt | Multi-module build for the subprojects |
| **Build (scripts)** | scala-cli | Quick scripts, prototyping, dev tooling. VirtusLab maintains it |

---

## Module Mapping: Laravel Illuminate -> SummerCMS

Each module = separate sbt subproject, publishable independently (like Illuminate packages).

| Illuminate Package | SummerCMS Module | Implementation Approach |
|-------------------|-----------------|------------------------|
| **Container** | `summer-backpack` | Scala 3 `given`/`using` for compile-time DI + lightweight runtime registry for plugins |
| **Contracts** | `summer-pact` | Scala traits — all public APIs defined here |
| **Support** | `summer-towel` | Extension methods, utility types, base classes |
| **Config** | `summer-compass` | Typesafe Config wrapper, HOCON files, standardized access across all modules |
| **Events** | `summer-festival` | Simple event bus with typed events + Ox channels for async |
| **Http** | `summer-surf` | Tapir endpoint definitions, request/response wrappers, routing (Tapir endpoints are type-safe routes) |
| **Database** | `summer-lagoon` | Magnum repos + case class models + query builder + pagination |
| **Auth** | `summer-bouncer` | JWT tokens (for API) + session cookies (for admin), guards as traits, session management |
| **Validation** | `summer-lifeguard` | Compile-time via Scala types + runtime rules engine (inspired by fields.yaml) |
| **Cache** | `summer-cooler` | Caffeine + Redis, driver-based via trait |
| **Queue** | `summer-conga` | Ox channels + virtual threads for workers, persistent queue via DB or Redis |
| **Mail** | `summer-postcard` | Jakarta Mail wrapper with template support |
| **Console** | `summer-bonfire` | CLI command framework for scaffolding (`summer create:plugin`, etc.) |
| **Filesystem** | `summer-sandcastle` | `java.nio.file` + pluggable storage providers (S3, etc.) via driver trait |
| **Translation** | `summer-phrasebook` | i18n with HOCON/JSON locale files |
| **View** | `summer-sunset` | Template engine for admin panel rendering |

### Illuminate Packages Not Ported (and why)

| Illuminate Package | Why not needed | Where it lives instead |
|-------------------|----------------|----------------------|
| **Pipeline** | Function composition is native to Scala (`f andThen g`). Laravel needs a Pipeline class because PHP lacks first-class functions. In Scala this is a one-liner, not a module. | Inline wherever needed |
| **Routing** | Tapir endpoint definitions ARE routes — defining an endpoint and defining a route is the same thing. No separate routing layer needed. | Merged into `summer-surf` (http) |
| **Session** | For an API-first CMS with JWT, sessions are thin — only needed for admin panel cookies. Not enough to justify a standalone module. | Merged into `summer-bouncer` (auth) |
| **Log** | SLF4J is already a logging facade. Wrapping a facade with another facade adds zero value. Just use SLF4J + Logback directly. | Direct SLF4J usage |
| **Collections** | Scala stdlib collections are already excellent — `List`, `Map`, `Seq`, `Vector` with `map`, `filter`, `fold`, etc. No wrapper needed. | Scala stdlib |
| **Pagination** | A paginator is a case class + a few helper methods. Too small for a standalone module. | Merged into `summer-lagoon` (database) |

---

## Plugin & Theme System

### Plugins

Each plugin = a directory with a `Plugin.scala` descriptor (same lifecycle as WinterCMS).

- Descriptor declares: models, controllers, components, console commands, event listeners, navigation items
- Plugins discovered at boot via classpath scanning or manifest
- Plugins can extend other plugins' models via Scala 3 extension methods + event hooks
- Plugin lifecycle: `register()` -> `boot()`

### Components

- Components are defined in plugins and placed in theme templates (like WinterCMS)
- Each component = a class with `onRun()`, properties, and a partial template
- Components handle their own data fetching and expose variables to templates
- Registered via plugin descriptor, auto-discovered by the theme engine

### Themes

- Theme = directory of templates + assets + config
- Templates rendered server-side (Scalate/Twirl) or served as SPA shell
- Components (from plugins) can be placed in theme templates

---

## Admin Backend

- Tapir endpoints serve as the admin API
- **YAML/JSON-driven forms** — same concept as WinterCMS `fields.yaml` / `columns.yaml`:
  - Plugin defines `fields.yaml` for model forms
  - Backend returns form schema as JSON, Vue frontend renders it
  - Field types: text, textarea, dropdown, relation, repeater, etc.
- **Admin frontend: Full SPA in Vue.js 3 + TypeScript** — consumes Tapir-generated typed API
  - TypeScript types auto-generated from Tapir OpenAPI spec
  - Vue components for form builder, list columns, relation managers, etc.

---

## Frontend-Backend Communication

- **Tapir-generated typed API** — all communication is via typed JSON endpoints
- OpenAPI spec auto-generated from Tapir endpoint definitions
- TypeScript client types generated from OpenAPI for the Vue admin SPA
- Public-facing sites can use the same API (headless mode) or server-rendered templates
- Headless mode: admin panel + API controllers serve as a superuser data presentation layer, frontend is fully decoupled

---

## Scaffolding Commands

```
summer create:plugin vendor.pluginname
summer create:model vendor.pluginname ModelName
summer create:controller vendor.pluginname ControllerName
summer create:component vendor.pluginname ComponentName
summer create:command vendor.pluginname CommandName
summer create:job vendor.pluginname JobName
summer create:migration vendor.pluginname description
```

---

## Project Structure

```
summercms/
  build.sbt                    # Multi-project sbt build
  modules/
    summer-backpack/           # DI container + plugin registry
    summer-pact/               # Contracts (traits)
    summer-towel/              # Support utilities
    summer-compass/            # Config
    summer-festival/           # Events
    summer-surf/               # HTTP + routing (Tapir)
    summer-lagoon/             # Database + pagination (Magnum)
    summer-bouncer/            # Auth + sessions
    summer-lifeguard/          # Validation
    summer-cooler/             # Cache
    summer-conga/              # Queue (Ox)
    summer-postcard/           # Mail
    summer-bonfire/            # Console / CLI
    summer-sandcastle/         # Filesystem + storage providers
    summer-phrasebook/         # Translation / i18n
    summer-sunset/             # View / templates
  app/                         # Full CMS application (depends on all modules)
    summer-cms/                # Assembled CMS with admin panel
  plugins/                     # Example/core plugins
    summer-plugin-user/
    summer-plugin-blog/
    summer-plugin-pages/
```