some ai generated code from claude that does not work

lib/mixer_web/live/magic_sign_in_live.ex

@@ -0,0 +1,184 @@
+defmodule MixerWeb.MagicSignInLive do
+  @moduledoc """
+  Custom magic-link sign-in LiveView that collects a username for new users.
+
+  When a user clicks their magic link, this page is shown instead of the
+  default auto-submit. If the user is brand new (no account) or has no
+  username set yet, we ask them to choose one before completing sign-in.
+  """
+
+  use AshAuthentication.Phoenix.Overrides.Overridable,
+    root_class: "CSS class for the root `div` element.",
+    magic_sign_in_id: "Element ID for the `MagicSignIn` LiveComponent."
+
+  use AshAuthentication.Phoenix.Web, :live_view
+
+  alias AshAuthentication.Info
+  alias AshPhoenix.Form
+  alias Phoenix.LiveView.{Rendered, Socket}
+
+  import AshAuthentication.Phoenix.Components.Helpers, only: [auth_path: 5]
+  import PhoenixHTMLHelpers.Form, only: [hidden_input: 3, submit: 2]
+  import Slug
+
+  @doc false
+  @impl true
+  def mount(params, session, socket) do
+    overrides =
+      session
+      |> Map.get("overrides", [AshAuthentication.Phoenix.Overrides.Default])
+
+    resource = session["resource"]
+    strategy_name = session["strategy"]
+    token = params["token"] || params["magic_link"]
+
+    strategy = Info.strategy!(resource, strategy_name)
+    subject_name = Info.authentication_subject_name!(resource)
+    domain = Info.authentication_domain!(resource)
+
+    # Determine whether this user needs to pick a username
+    needs_username? = needs_username?(token, resource)
+
+    form =
+      resource
+      |> Form.for_action(strategy.sign_in_action_name,
+        domain: domain,
+        as: subject_name |> to_string(),
+        id: "#{subject_name}-#{strategy_name}-sign-in-form" |> slugify(),
+        context: %{strategy: strategy, private: %{ash_authentication?: true}}
+      )
+
+    socket =
+      socket
+      |> assign(overrides: overrides)
+      |> assign(:token, token)
+      |> assign(:strategy, strategy)
+      |> assign(:subject_name, subject_name)
+      |> assign(:resource, resource)
+      |> assign(:needs_username?, needs_username?)
+      |> assign(:form, form)
+      |> assign(:trigger_action, false)
+      |> assign(:current_tenant, session["tenant"])
+      |> assign(:auth_routes_prefix, session["auth_routes_prefix"])
+
+    {:ok, socket}
+  end
+
+  @doc false
+  @impl true
+  @spec handle_params(map, String.t(), Socket.t()) :: {:noreply, Socket.t()}
+  def handle_params(_params, _uri, socket), do: {:noreply, socket}
+
+  @doc false
+  @impl true
+  @spec render(Socket.assigns()) :: Rendered.t()
+  def render(assigns) do
+    ~H"""
+    <div class={override_for(@overrides, :root_class)}>
+      <.live_component
+        module={AshAuthentication.Phoenix.Components.Banner}
+        id="magic-sign-in-banner"
+        overrides={@overrides}
+      />
+
+      <div style="max-width: 400px; margin: 0 auto; padding: 1rem;">
+        <.form
+          :let={form}
+          for={@form}
+          phx-submit="submit"
+          phx-trigger-action={@trigger_action}
+          action={
+            auth_path(
+              @socket,
+              @subject_name,
+              @auth_routes_prefix,
+              @strategy,
+              :sign_in
+            )
+          }
+          method="POST"
+        >
+          {hidden_input(form, :token, value: @token)}
+
+          <%!-- Username field — only shown for new or username-less users --%>
+          <div :if={@needs_username?} class="mt-2 mb-4">
+            <label
+              for={form[:username].id}
+              class="block text-sm font-medium text-base-content mb-1"
+            >
+              Choose a username
+            </label>
+            <div class="flex">
+              <span class="input rounded-r-none border-r-0 text-base-content/50 select-none">
+                @
+              </span>
+              <input
+                type="text"
+                id={form[:username].id}
+                name={form[:username].name}
+                value={form[:username].value || ""}
+                class={"input w-full rounded-l-none #{if form[:username].errors != [], do: "input-error", else: ""}"}
+                placeholder="your_handle"
+                autocomplete="username"
+                required
+              />
+            </div>
+            <p
+              :if={form[:username].errors != []}
+              class="mt-1 text-xs text-error"
+            >
+              {form[:username].errors |> List.first() |> elem(0)}
+            </p>
+            <p :if={form[:username].errors == []} class="mt-1 text-xs text-base-content/50">
+              3–30 characters · letters, numbers, underscores
+            </p>
+          </div>
+
+          {submit("Sign in",
+            class: "btn btn-primary w-full mt-2",
+            phx_disable_with: "Signing in…"
+          )}
+        </.form>
+      </div>
+    </div>
+    """
+  end
+
+  @doc false
+  @impl true
+  @spec handle_event(String.t(), map(), Socket.t()) :: {:noreply, Socket.t()}
+  def handle_event("submit", params, socket) do
+    subject_name =
+      socket.assigns.subject_name
+      |> to_string()
+      |> slugify()
+
+    form_params = Map.get(params, subject_name, %{})
+
+    form = Form.validate(socket.assigns.form, form_params)
+
+    socket =
+      socket
+      |> assign(:form, form)
+      |> assign(:trigger_action, form.valid?)
+
+    {:noreply, socket}
+  end
+
+  # ── Helpers ──────────────────────────────────────────────────────────────────
+
+  # Returns true if the user is new or has no username set yet.
+  defp needs_username?(nil, _resource), do: true
+
+  defp needs_username?(token, resource) do
+    with {:ok, claims} <- AshAuthentication.Jwt.peek(token),
+         subject when is_binary(subject) <- Map.get(claims, "sub"),
+         {:ok, user} <- AshAuthentication.subject_to_user(subject, resource) do
+      is_nil(user.username)
+    else
+      _ ->
+        # Unknown / new user — ask for username to be safe
+        true
+    end
+  end
+end