# `PhoenixKitAI.Components.AITranslate.FormBinding`
[🔗](https://github.com/BeamLabEU/phoenix_kit_ai/blob/v0.4.0/lib/phoenix_kit_ai/components/ai_translate/form_binding.ex#L1)

The small storage-specific contract a form LiveView supplies to the
shared AI-translate glue (`PhoenixKitAI.Components.AITranslate.FormGlue`).

Everything about the modal/progress/stall state machine, the dispatch, and
the PubSub event handling is generic and lives in the glue. The only things
that differ per consumer are *where/how translations are stored in the live
changeset* and *who the actor is* — those three callbacks.

Implementations are tiny modules (see `PhoenixKitCatalogue.AITranslateBinding`
/ `PhoenixKitProjects.AITranslateBinding`). The module is passed once to
`FormGlue.assign_ai_translation/4` and stashed in assigns.

# `actor_uuid`

```elixir
@callback actor_uuid(socket :: Phoenix.LiveView.Socket.t()) :: Ecto.UUID.t() | nil
```

The acting user's UUID (or nil) for the translation audit trail.

# `apply_translation`

```elixir
@callback apply_translation(
  resource_type :: String.t(),
  changeset :: Ecto.Changeset.t(),
  lang :: String.t(),
  fields :: map()
) :: Ecto.Changeset.t()
```

Merge a completed translation's `fields` (plain engine field names →
translated values) into `changeset` for `lang`, returning the updated
changeset. PURE changeset→changeset — the glue re-assigns it via the LV's
own assign helper, so this must not touch the socket.

# `existing_translation_langs`

```elixir
@callback existing_translation_langs(resource_type :: String.t(), assigns :: map()) :: [
  String.t()
]
```

The enabled non-primary language codes that ALREADY have at least one
non-blank translatable field, read from the live form's assigns (so it
reflects unsaved + just-translated state). The glue subtracts these from the
enabled set to get the "missing" list.

---

*Consult [api-reference.md](api-reference.md) for complete listing*