# `PhoenixKitComments.Embed`
[🔗](https://github.com/BeamLabEU/phoenix_kit_comments/blob/v0.4.7/lib/phoenix_kit_comments/embed.ex#L1)

Host-side wiring for embedding `PhoenixKitComments.Web.CommentsComponent`.

## Why this exists

The comment composer's rich-text (Leaf) editor reports its content to the
**host LiveView** via a `{:leaf_changed, ...}` process message — a
`LiveComponent` has no `handle_info/2` of its own, so the message can only
land in the host. On submit, `CommentsComponent` reads its `new_comment`
assign (the form params don't carry Leaf's contenteditable). Without the
host forwarding `{:leaf_changed, ...}` back into the component via
`CommentsComponent.forward_leaf_event/2`, the editor's content never
reaches it and "Post comment" silently no-ops.

This is easy to forget (it's a process-message hop, invisible in the
component's own markup). `use PhoenixKitComments.Embed` wires it for you.

## Usage

    defmodule MyAppWeb.ThingShowLive do
      use MyAppWeb, :live_view
      use PhoenixKitComments.Embed
      # ...render <.live_component module={PhoenixKitComments.Web.CommentsComponent} ... />
    end

## How it composes

The forward is attached as a `:handle_info` lifecycle hook in an
`on_mount/4` (not injected `handle_info` clauses), so it **composes** with
a host that already defines its own `handle_info` — no "clauses should be
grouped" warning, no clobbering. Non-comments messages pass straight
through (`{:cont, socket}`); a `{:leaf_changed, ...}` for one of our
editors is forwarded and halted. Mirrors the lifecycle-hook approach
`PhoenixKitWeb.Components.MediaBrowser.Embed` uses for the same purpose.

## Hard-dep only

`use` is compile-time, so only hosts that **depend on**
`phoenix_kit_comments` can use this. A host where comments is *optional*
(a soft dep) must instead resolve and call `forward_leaf_event/2` at
runtime — see `phoenix_kit_staff`'s `PersonShowLive`:

    def handle_info({:leaf_changed, _} = msg, socket) do
      case Code.ensure_loaded(PhoenixKitComments.Web.CommentsComponent) do
        {:module, mod} ->
          case mod.forward_leaf_event(msg, socket) do
            # A comments editor — already handled.
            {:noreply, _} = ok -> ok
            # `:pass` means the event is *not* a comments editor (its
            # `editor_id` isn't `"pk-comments:"`-prefixed). Fall through
            # to the host's own Leaf handling here; the bare
            # `{:noreply, socket}` only fits a host whose *only* Leaf
            # editor is the comments composer — otherwise it silently
            # swallows the host's own editor events.
            :pass -> {:noreply, socket}
          end

        # Comments package isn't installed — nothing to forward.
        _ ->
          {:noreply, socket}
      end
    end

---

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