refactor: improve email copy with MapSet, RFC 5322 commas, and cond

Performance optimization, RFC-compliant separator, better tests

lib/mv_web/live/member_live/index.ex

@@ -59,7 +59,7 @@ defmodule MvWeb.MemberLive.Index do
       |> assign(:query, "")
       |> assign_new(:sort_field, fn -> :first_name end)
       |> assign_new(:sort_order, fn -> :asc end)
-      |> assign(:selected_members, [])
+      |> assign(:selected_members, MapSet.new())
       |> assign(:custom_fields_visible, custom_fields_visible)
 
     # We call handle params to use the query from the URL
@@ -92,10 +92,10 @@ defmodule MvWeb.MemberLive.Index do
   @impl true
   def handle_event("select_member", %{"id" => id}, socket) do
     selected =
-      if id in socket.assigns.selected_members do
-        List.delete(socket.assigns.selected_members, id)
+      if MapSet.member?(socket.assigns.selected_members, id) do
+        MapSet.delete(socket.assigns.selected_members, id)
       else
-        [id | socket.assigns.selected_members]
+        MapSet.put(socket.assigns.selected_members, id)
       end
 
     {:noreply, assign(socket, :selected_members, selected)}
@@ -103,13 +103,11 @@ defmodule MvWeb.MemberLive.Index do
 
   @impl true
   def handle_event("select_all", _params, socket) do
-    members = socket.assigns.members
-
-    all_ids = Enum.map(members, & &1.id)
+    all_ids = socket.assigns.members |> Enum.map(& &1.id) |> MapSet.new()
 
     selected =
-      if Enum.sort(socket.assigns.selected_members) == Enum.sort(all_ids) do
-        []
+      if MapSet.equal?(socket.assigns.selected_members, all_ids) do
+        MapSet.new()
       else
         all_ids
       end
@@ -121,26 +119,26 @@ defmodule MvWeb.MemberLive.Index do
   def handle_event("copy_emails", _params, socket) do
     selected_ids = socket.assigns.selected_members
 
-    if selected_ids == [] do
-      {:noreply, put_flash(socket, :error, gettext("No members selected"))}
-    else
-      # Filter members that are in the selection
-      selected_members =
-        socket.assigns.members
-        |> Enum.filter(fn member -> member.id in selected_ids end)
+    # Filter members that are in the selection and have email addresses
+    formatted_emails =
+      socket.assigns.members
+      |> Enum.filter(fn member ->
+        MapSet.member?(selected_ids, member.id) && member.email && member.email != ""
+      end)
+      |> Enum.map(&format_member_email/1)
 
-      # Format emails and filter out members without email
-      formatted_emails =
-        selected_members
-        |> Enum.filter(fn member -> member.email && member.email != "" end)
-        |> Enum.map(&format_member_email/1)
+    email_count = length(formatted_emails)
 
-      email_count = length(formatted_emails)
+    cond do
+      MapSet.size(selected_ids) == 0 ->
+        {:noreply, put_flash(socket, :error, gettext("No members selected"))}
 
-      if email_count == 0 do
+      email_count == 0 ->
         {:noreply, put_flash(socket, :error, gettext("No email addresses found"))}
-      else
-        email_string = Enum.join(formatted_emails, "; ")
+
+      true ->
+        # RFC 5322 uses comma as separator for email address lists
+        email_string = Enum.join(formatted_emails, ", ")
 
         socket =
           socket
@@ -160,7 +158,6 @@ defmodule MvWeb.MemberLive.Index do
           )
 
         {:noreply, socket}
-      end
     end
   end