# PhoenixKit Publishing

A standalone PhoenixKit plugin module that provides a database-backed content management system with multi-language support, collaborative editing, and dual URL modes.

## Installation

Add to your parent app's `mix.exs`:

```elixir
{:phoenix_kit_publishing, "~> 0.1"}
```

Or for local development:

```elixir
{:phoenix_kit_publishing, path: "../phoenix_kit_publishing"}
```

Then run `mix deps.get` and `mix phoenix_kit.install`. The module is auto-discovered by PhoenixKit at startup — no additional config needed. The installer also adds the necessary Tailwind CSS `@source` directive so all styles render correctly.

### Database Setup

The publishing tables (`phoenix_kit_publishing_groups`, `_posts`, `_versions`, `_contents`) are created by PhoenixKit's core versioned migrations (V59). Run `mix phoenix_kit.install` in the host app and they're set up automatically — no module-owned migration to invoke.

### Enable the Module

Via admin UI: navigate to Admin > Modules > Publishing > toggle on.

Or via code:

```elixir
PhoenixKit.Modules.Publishing.enable_system()
```

## Features

- **Dual URL Modes** — Timestamp-based (blog/news) or slug-based (docs/FAQ), locked at group creation
- **Multi-Language Support** — Separate content per language with language switcher and smart fallbacks
- **Versioning** — Independent version history per post with publish/archive controls
- **Collaborative Editing** — Real-time presence tracking with owner/spectator locking
- **AI Translation** — Background translation via OpenRouter integration (Oban workers)
- **Two-Layer Caching** — Listing cache (`:persistent_term`, ~0.1us reads) + render cache (ETS, 6hr TTL)
- **Rich Content** — Markdown + inline PHK components (Image, Hero, CTA, Video, Headline, EntityForm)
- **Admin Interface** — Full CRUD with inline status controls, skeleton loading, trash management
- **Public Routes** — SEO-friendly URLs with smart language/date fallbacks, pagination, breadcrumbs
- **Featured Images** — Media library integration via PhoenixKit's MediaSelectorModal

## URL Modes

### Timestamp Mode (default)

Posts addressed by publication date and time. Ideal for news, announcements, changelogs.

```
/{language}/{group-slug}/{YYYY-MM-DD}/{HH:MM}
```

### Slug Mode

Posts addressed by semantic slug. Ideal for documentation, guides, evergreen content.

```
/{language}/{group-slug}/{post-slug}
```

Single-language mode omits the language segment automatically.

## Architecture

### Database Schema (4 tables)

```
Group (1) ──→ (many) Post (1) ──→ (many) Version (1) ──→ (many) Content
```

#### `phoenix_kit_publishing_groups` — Content containers

| Column | Type | Purpose |
|--------|------|---------|
| uuid | UUIDv7 | PK |
| name | string | Display name |
| slug | string | URL identifier (unique) |
| mode | string | `"timestamp"` or `"slug"` — locked at creation |
| status | string | `"active"` or `"trashed"` |
| position | integer | Display ordering |
| data | JSONB | type, item_singular/plural, icon, comments/likes/views_enabled |
| title_i18n | JSONB | Translatable group title (keyed by language code) |
| description_i18n | JSONB | Translatable group description (keyed by language code) |

#### `phoenix_kit_publishing_posts` — Routing shell

Posts hold URL identity and point to their live version. No content or metadata — that lives on versions.

| Column | Type | Purpose |
|--------|------|---------|
| uuid | UUIDv7 | PK |
| group_uuid | UUIDv7 | FK → groups |
| slug | string | URL path segment (slug mode, unique per group) |
| mode | string | `"timestamp"` or `"slug"` |
| post_date | date | URL date segment (timestamp mode) |
| post_time | time | URL time segment (timestamp mode, unique per group+date) |
| active_version_uuid | UUIDv7 | FK → versions — the live version (null = unpublished) |
| trashed_at | utc_datetime | Soft delete timestamp (null = active) |
| created_by_uuid | UUIDv7 | FK → users (audit) |
| updated_by_uuid | UUIDv7 | FK → users (audit) |

Publishing = setting `active_version_uuid`. Trashing = setting `trashed_at`.

#### `phoenix_kit_publishing_versions` — Source of truth

Each post has one or more versions. The version holds all metadata that applies across languages.

| Column | Type | Purpose |
|--------|------|---------|
| uuid | UUIDv7 | PK |
| post_uuid | UUIDv7 | FK → posts |
| version_number | integer | Sequential (v1, v2, ...), unique per post |
| status | string | `"draft"` / `"published"` / `"archived"` |
| published_at | utc_datetime | When this version was first published |
| created_by_uuid | UUIDv7 | FK → users (audit) |
| data | JSONB | featured_image_uuid, tags, seo, description, allow_version_access, notes, created_from |

#### `phoenix_kit_publishing_contents` — Per-language title + body

One row per language per version. All languages share the version's status and metadata.

| Column | Type | Purpose |
|--------|------|---------|
| uuid | UUIDv7 | PK |
| version_uuid | UUIDv7 | FK → versions |
| language | string | Language code (unique per version) |
| title | string | Post title in this language |
| content | text | Markdown/PHK body in this language |
| url_slug | string | Per-language URL slug (for localized URLs) |
| status | string | Reserved for future per-language overrides (unused by UI) |
| data | JSONB | Reserved for future per-language overrides (unused by UI) |

All tables use UUIDv7 primary keys. Language fallback chain: requested language → site default → first available.

### Module Structure

```
lib/phoenix_kit_publishing/
  publishing.ex              # Main facade (PhoenixKit.Module behaviour)
  groups.ex                  # Group CRUD
  posts.ex                   # Post operations
  versions.ex                # Version management
  translation_manager.ex     # Language/translation ops
  db_storage.ex              # Database CRUD layer
  listing_cache.ex           # In-memory listing cache
  renderer.ex                # Markdown + component rendering
  page_builder.ex            # PHK XML component system
  stale_fixer.ex             # Data consistency repair
  presence.ex                # Collaborative editing presence
  pubsub.ex                  # Real-time broadcasting
  routes.ex                  # Admin route definitions
  schemas/                   # Ecto schemas (4 files)
  web/                       # LiveViews, controller, templates
  workers/                   # Oban background jobs
```

### Core Modules

| Module | Role |
|--------|------|
| `PhoenixKit.Modules.Publishing` | Main context/facade — delegates to all submodules |
| `Publishing.DBStorage` | Direct Ecto queries for all CRUD operations |
| `Publishing.ListingCache` | `:persistent_term` cache with sub-microsecond reads |
| `Publishing.Renderer` | MDEx markdown + PHK component rendering with ETS cache |
| `Publishing.PageBuilder` | XML parser (Saxy) for `<Image>`, `<Hero>`, etc. components |
| `Publishing.StaleFixer` | Reconciles DB/cache state, auto-cleans empty posts |
| `Publishing.Presence` | Phoenix.Presence for collaborative editor locking |

## IEx / CLI Usage

```elixir
alias PhoenixKit.Modules.Publishing

# Groups
{:ok, _} = Publishing.add_group("Documentation", mode: "slug")
{:ok, _} = Publishing.add_group("Company News", mode: "timestamp")
Publishing.list_groups()

# Posts
{:ok, post} = Publishing.create_post("docs", %{title: "Getting Started"})
{:ok, post} = Publishing.read_post("docs", "getting-started")
{:ok, _} = Publishing.update_post("docs", post, %{"content" => "# Updated"})

# Translations
{:ok, _} = Publishing.add_language_to_post("docs", post_uuid, "es")
:ok = Publishing.delete_language("docs", post_uuid, "fr")

# Versions
{:ok, v2} = Publishing.create_version_from("docs", post_uuid, 1)
:ok = Publishing.publish_version("docs", post_uuid, 2)

# Cache
Publishing.regenerate_cache("docs")
Publishing.invalidate_cache("docs")
```

## Admin Routes

| Route | LiveView | Purpose |
|-------|----------|---------|
| `/admin/publishing` | Index | Groups overview |
| `/admin/publishing/new-group` | New | Create group |
| `/admin/publishing/edit-group/:group` | Edit | Group settings |
| `/admin/publishing/:group` | Listing | Posts list with status tabs |
| `/admin/publishing/:group/new` | Editor | Create post |
| `/admin/publishing/:group/:uuid/edit` | Editor | Edit post |
| `/admin/publishing/:group/preview` | Preview | Live preview |
| `/admin/settings/publishing` | Settings | Cache config |

## Public Routes

Multi-language mode:
```
/{language}/{group-slug}                           # Group listing
/{language}/{group-slug}/{post-slug}               # Slug-mode post
/{language}/{group-slug}/{post-slug}/v/{version}   # Versioned post
/{language}/{group-slug}/{date}/{time}             # Timestamp-mode post
```

Single-language mode omits the `/{language}` segment.

When `publishing_default_language_no_prefix` is enabled, the default-language URL also drops its prefix (e.g. `/blog` instead of `/en/blog`), and requests to the prefixed form 301-redirect to the canonical prefixless URL.

### Fallback Behavior

- Missing language → tries default language, then other available languages
- Missing timestamp post → tries other times on same date, then group listing
- All fallbacks include a flash message explaining the redirect
- Invalid group slugs fall back to 404 only after exhausting all alternatives

### How Dispatch Works (and how it interacts with host routes)

Public URLs are dynamic — the group slug is a database row, not a compile-time
literal — so these routes can't be declared normally. Publishing registers its
catch-all under an internal prefix and overrides the host router's `call/2`
(`RouterDispatch`): on each `GET`/`HEAD`, if the first non-locale path segment
matches a known group slug, the path is rewritten to the internal prefix and
Phoenix matches it there. Otherwise the request passes through untouched.

Two consequences worth knowing:

- **A host route whose first segment equals a group slug will never match.** The
  rewrite happens in `call/2`, before route matching — declaration order in
  `router.ex` doesn't help. Only `GET`/`HEAD` are rewritten, so a `POST /blog/...`
  still reaches the host.
- **`mix phx.routes` shows these routes under `__phoenix_kit_publishing_dispatch`**,
  not at their public paths.

### Reserved Route Prefixes

Another PhoenixKit module can claim a top-level segment by implementing
`PhoenixKit.Module.reserved_route_prefixes/0` (added in `phoenix_kit` 1.7.170):

```elixir
@impl PhoenixKit.Module
def reserved_route_prefixes, do: ["shop"]
```

`RouterDispatch.known_group?/1` consults
`PhoenixKit.ModuleRegistry.all_reserved_route_prefixes/0` and refuses to claim a
reserved segment **even when a group with that exact slug exists in publishing's
own data**. On `phoenix_kit` older than 1.7.170 the callback is absent and nothing
is reserved.

Reserve a prefix only if your module actually renders that route — a reservation
removes the path from publishing's dispatch, and if nothing takes over, the result
is a 404. `phoenix_kit_legal` reserved `"legal"` in its 0.1.6 without shipping a
renderer and 404'd public legal pages on every host app; it was reverted in 0.1.7,
and legal pages are once again served here as an ordinary group. If your module
stores its content as publishing posts, letting publishing render them is usually
the right call — you inherit languages, translations, canonical/`og:*`/hreflang,
and the editor for free.

## Caching

### Listing Cache

Uses `:persistent_term` for near-zero-cost reads. Invalidated on post create/update, status change, translation add, or version create.

```elixir
Publishing.regenerate_cache("my-blog")
Publishing.find_cached_post("my-blog", "post-slug")
```

### Render Cache

ETS-based with 6-hour TTL and content-hash keys. Toggled globally or per-group:

```elixir
# Global toggle
PhoenixKit.Settings.update_setting("publishing_render_cache_enabled", "true")

# Per-group toggle
PhoenixKit.Settings.update_setting("publishing_render_cache_enabled_docs", "false")

# Manual clear
PhoenixKit.Modules.Publishing.Renderer.clear_group_cache("docs")
PhoenixKit.Modules.Publishing.Renderer.clear_all_cache()
```

## Content Format

Posts use Markdown with optional PHK components:

```markdown
# My Post Title

Regular **Markdown** content with all GitHub-flavored features.

<Image file_id="019a6f96-..." alt="Description" />

<Hero variant="centered">
  <Headline>Welcome</Headline>
  <CTA primary="true" action="/signup">Get Started</CTA>
</Hero>

<EntityForm entity="contact" />
```

Supported components: `Image`, `Hero`, `CTA`, `Headline`, `Subheadline`, `Video`, `EntityForm`.

## Settings

| Key | Default | Description |
|-----|---------|-------------|
| `publishing_enabled` | `false` | Enable/disable module |
| `publishing_public_enabled` | `true` | Show public routes |
| `publishing_default_language_no_prefix` | `false` | Omit the locale prefix from default-language public URLs; prefixed requests 301-redirect |
| `publishing_posts_per_page` | `20` | Listing pagination |
| `publishing_memory_cache_enabled` | `true` | Listing cache toggle |
| `publishing_render_cache_enabled` | `true` | Render cache global toggle |
| `publishing_render_cache_enabled_<slug>` | `true` | Per-group render cache |

## Testing

Unit tests run without a database. Integration and controller tests require PostgreSQL:

```bash
createdb phoenix_kit_publishing_test
mix test
```

Integration tests are automatically excluded when the database is unavailable. Controller tests run through a minimal `Phoenix.Endpoint` + `Router` + `Layouts` shipped under `test/support/` — see `AGENTS.md` for details.

## Dependencies

| Package | Purpose |
|---------|---------|
| `phoenix_kit` | Module behaviour, Settings, Auth, Cache, shared components |
| `phoenix_live_view` | Admin LiveView pages |
| `mdex` | Markdown rendering (comrak) |
| `saxy` | XML parsing for PHK components |
| `oban` | Background translation and migration workers |

## License

MIT