feat: improve groups fillter

docs/feature-roadmap.md

@@ -85,6 +85,7 @@
   - Many-to-many relationship with groups
   - Groups management UI (`/groups`)
   - Filter and sort by groups in member list
+  - Per-group filter in member list: one row per group with All / Yes / No (All/Alle); URL params `group_<uuid>=in|not_in`
   - Groups displayed in member overview and detail views
 - ✅ **CSV Import** - Import members from CSV files (PR #359, #394, #395, closes #335, #336, #338, 2026-01-27)
   - Member field import

lib/mv_web/live/components/member_filter_component.ex

@@ -16,6 +16,8 @@ defmodule MvWeb.Components.MemberFilterComponent do
 
   ## Props
   - `:cycle_status_filter` - Current payment filter state: `nil` (all), `:paid`, or `:unpaid`
+  - `:groups` - List of groups (for per-group filter rows)
+  - `:group_filters` - Map of active group filters: `%{group_id => :in | :not_in}` (nil = All for that group)
   - `:boolean_custom_fields` - List of boolean custom fields to display
   - `:boolean_filters` - Map of active boolean filters: `%{custom_field_id => true | false}`
   - `:id` - Component ID (required)
@@ -23,6 +25,7 @@ defmodule MvWeb.Components.MemberFilterComponent do
 
   ## Events
   - Sends `{:payment_filter_changed, filter}` to parent when payment filter changes
+  - Sends `{:group_filter_changed, group_id_str, value}` to parent when a group filter changes (value: nil | :in | :not_in)
   - Sends `{:boolean_filter_changed, custom_field_id, filter_value}` to parent when boolean filter changes
   """
   use MvWeb, :live_component
@@ -38,6 +41,8 @@ defmodule MvWeb.Components.MemberFilterComponent do
       socket
       |> assign(:id, assigns.id)
       |> assign(:cycle_status_filter, assigns[:cycle_status_filter])
+      |> assign(:groups, assigns[:groups] || [])
+      |> assign(:group_filters, assigns[:group_filters] || %{})
       |> assign(:boolean_custom_fields, assigns[:boolean_custom_fields] || [])
       |> assign(:boolean_filters, assigns[:boolean_filters] || %{})
       |> assign(:member_count, assigns[:member_count] || 0)
@@ -60,7 +65,9 @@ defmodule MvWeb.Components.MemberFilterComponent do
         tabindex="0"
         class={[
           "btn gap-2",
-          (@cycle_status_filter || active_boolean_filters_count(@boolean_filters) > 0) && "btn-active"
+          (@cycle_status_filter || map_size(@group_filters) > 0 ||
+             active_boolean_filters_count(@boolean_filters) > 0) &&
+            "btn-active"
         ]}
         phx-click="toggle_dropdown"
         phx-target={@myself}
@@ -70,7 +77,13 @@ defmodule MvWeb.Components.MemberFilterComponent do
       >
         <.icon name="hero-funnel" class="h-5 w-5" />
         <span class="hidden sm:inline">
-          {button_label(@cycle_status_filter, @boolean_custom_fields, @boolean_filters)}
+          {button_label(
+            @cycle_status_filter,
+            @groups,
+            @group_filters,
+            @boolean_custom_fields,
+            @boolean_filters
+          )}
         </span>
         <span
           :if={active_boolean_filters_count(@boolean_filters) > 0}
@@ -79,7 +92,10 @@ defmodule MvWeb.Components.MemberFilterComponent do
           {active_boolean_filters_count(@boolean_filters)}
         </span>
         <span
-          :if={@cycle_status_filter && active_boolean_filters_count(@boolean_filters) == 0}
+          :if={
+            (@cycle_status_filter || map_size(@group_filters) > 0) &&
+              active_boolean_filters_count(@boolean_filters) == 0
+          }
           class="badge badge-primary badge-sm"
         >
           {@member_count}
@@ -103,7 +119,7 @@ defmodule MvWeb.Components.MemberFilterComponent do
         role="dialog"
         aria-label={gettext("Member filter")}
       >
-        <form phx-change="update_filters" phx-target={@myself}>
+        <form phx-change="update_filters" phx-target={@myself} data-testid="member-filter-form">
           <!-- Payment Filter Group -->
           <div class="mb-4">
             <div class="text-xs font-semibold opacity-70 mb-2 uppercase tracking-wider">
@@ -162,6 +178,73 @@ defmodule MvWeb.Components.MemberFilterComponent do
             </fieldset>
           </div>
           
+    <!-- Groups: one row per group with All / Yes / No (like Custom Fields) -->
+          <div :if={length(@groups) > 0} class="mb-4">
+            <div class="text-xs font-semibold opacity-70 mb-2 uppercase tracking-wider">
+              {gettext("Groups")}
+            </div>
+            <div class="max-h-60 overflow-y-auto pr-2">
+              <fieldset
+                :for={group <- @groups}
+                class="grid grid-cols-[1fr_auto] items-center gap-3 py-2 border-b border-base-200 last:border-0 border-0 p-0 m-0 min-w-0"
+              >
+                <legend class="text-sm font-medium col-start-1 float-left w-auto">
+                  {group.name}
+                </legend>
+                <div class="join col-start-2">
+                  <label
+                    class={"#{group_filter_label_class(@group_filters, group.id, nil)} has-[:focus-visible]:ring-2 has-[:focus-visible]:ring-primary"}
+                    for={"group-filter-#{group.id}-all"}
+                  >
+                    <input
+                      type="radio"
+                      id={"group-filter-#{group.id}-all"}
+                      name={"group_#{group.id}"}
+                      value="all"
+                      class="absolute opacity-0 w-0 h-0 pointer-events-none"
+                      checked={Map.get(@group_filters, to_string(group.id)) == nil}
+                    />
+                    <span class="text-xs">{gettext("All")}</span>
+                  </label>
+                  <label
+                    class={"#{group_filter_label_class(@group_filters, group.id, :in)} has-[:focus-visible]:ring-2 has-[:focus-visible]:ring-primary"}
+                    for={"group-filter-#{group.id}-in"}
+                    aria-label={gettext("Yes")}
+                    title={gettext("Yes")}
+                  >
+                    <input
+                      type="radio"
+                      id={"group-filter-#{group.id}-in"}
+                      name={"group_#{group.id}"}
+                      value="in"
+                      class="absolute opacity-0 w-0 h-0 pointer-events-none"
+                      checked={Map.get(@group_filters, to_string(group.id)) == :in}
+                    />
+                    <.icon name="hero-check-circle" class="h-5 w-5" />
+                    <span class="text-xs">{gettext("Yes")}</span>
+                  </label>
+                  <label
+                    class={"#{group_filter_label_class(@group_filters, group.id, :not_in)} has-[:focus-visible]:ring-2 has-[:focus-visible]:ring-primary"}
+                    for={"group-filter-#{group.id}-not-in"}
+                    aria-label={gettext("No")}
+                    title={gettext("No")}
+                  >
+                    <input
+                      type="radio"
+                      id={"group-filter-#{group.id}-not-in"}
+                      name={"group_#{group.id}"}
+                      value="not_in"
+                      class="absolute opacity-0 w-0 h-0 pointer-events-none"
+                      checked={Map.get(@group_filters, to_string(group.id)) == :not_in}
+                    />
+                    <.icon name="hero-x-circle" class="h-5 w-5" />
+                    <span class="text-xs">{gettext("No")}</span>
+                  </label>
+                </div>
+              </fieldset>
+            </div>
+          </div>
+          
     <!-- Custom Fields Group -->
           <div :if={length(@boolean_custom_fields) > 0} class="mb-2">
             <div class="text-xs font-semibold opacity-70 mb-2 uppercase tracking-wider">
@@ -274,6 +357,16 @@ defmodule MvWeb.Components.MemberFilterComponent do
         _ -> nil
       end
 
+    # Parse per-group filters (params keys "group_<uuid>" => "all"|"in"|"not_in")
+    group_filters_parsed =
+      params
+      |> Enum.filter(fn {key, _} -> String.starts_with?(key, "group_") end)
+      |> Enum.reduce(%{}, fn {key, value_str}, acc ->
+        group_id_str = String.slice(key, 6, String.length(key) - 6)
+        filter_value = parse_group_filter_value(value_str)
+        Map.put(acc, group_id_str, filter_value)
+      end)
+
     # Parse boolean custom field filters (including nil values for "all")
     custom_boolean_filters_parsed =
       params
@@ -288,6 +381,21 @@ defmodule MvWeb.Components.MemberFilterComponent do
       send(self(), {:payment_filter_changed, payment_filter})
     end
 
+    # Update group filters - send event for each changed group
+    current_group_filters = socket.assigns.group_filters
+    all_group_ids = MapSet.new(Enum.map(socket.assigns.groups, &to_string(&1.id)))
+
+    Enum.each(group_filters_parsed, fn {group_id_str, new_value} ->
+      in_set = MapSet.member?(all_group_ids, group_id_str)
+      current_value = Map.get(current_group_filters, group_id_str)
+      normalized_new = if new_value == nil, do: nil, else: new_value
+      should_send = in_set and current_value != normalized_new
+
+      if should_send do
+        send(self(), {:group_filter_changed, group_id_str, normalized_new})
+      end
+    end)
+
     # Update boolean filters - send events for each changed filter
     current_filters = socket.assigns.boolean_filters
 
@@ -310,7 +418,7 @@ defmodule MvWeb.Components.MemberFilterComponent do
   def handle_event("reset_filters", _params, socket) do
     # Send single message to reset all filters at once (performance optimization)
     # This avoids N×2 load_members() calls when resetting multiple filters
-    send(self(), {:reset_all_filters, nil, %{}})
+    send(self(), {:reset_all_filters, nil, %{}, %{}})
 
     # Close dropdown after reset
     {:noreply, assign(socket, :open, false)}
@@ -322,17 +430,49 @@ defmodule MvWeb.Components.MemberFilterComponent do
   defp parse_tri_state("all"), do: nil
   defp parse_tri_state(_), do: nil
 
+  defp parse_group_filter_value("in"), do: :in
+  defp parse_group_filter_value("not_in"), do: :not_in
+  defp parse_group_filter_value(_), do: nil
+
   # Get display label for button
-  defp button_label(cycle_status_filter, boolean_custom_fields, boolean_filters) do
-    # If payment filter is active, show payment filter label
-    if cycle_status_filter do
-      payment_filter_label(cycle_status_filter)
-    else
-      # Otherwise show boolean filter labels
-      boolean_filter_label(boolean_custom_fields, boolean_filters)
+  defp button_label(
+         cycle_status_filter,
+         groups,
+         group_filters,
+         boolean_custom_fields,
+         boolean_filters
+       ) do
+    cond do
+      cycle_status_filter ->
+        payment_filter_label(cycle_status_filter)
+
+      map_size(group_filters) > 0 ->
+        group_filters_label(groups, group_filters)
+
+      map_size(boolean_filters) > 0 ->
+        boolean_filter_label(boolean_custom_fields, boolean_filters)
+
+      true ->
+        gettext("All")
     end
   end
 
+  defp group_filters_label(_groups, group_filters) when map_size(group_filters) == 0,
+    do: gettext("All")
+
+  defp group_filters_label(groups, group_filters) do
+    names =
+      group_filters
+      |> Enum.map(fn {group_id_str, _} ->
+        Enum.find(groups, fn g -> to_string(g.id) == group_id_str end)
+      end)
+      |> Enum.filter(&(&1 != nil))
+      |> Enum.map(& &1.name)
+
+    label = Enum.join(names, ", ")
+    truncate_label(label, 30)
+  end
+
   # Get payment filter label
   defp payment_filter_label(nil), do: gettext("All")
   defp payment_filter_label(:paid), do: gettext("Paid")
@@ -406,6 +546,39 @@ defmodule MvWeb.Components.MemberFilterComponent do
     end
   end
 
+  # Get CSS classes for per-group filter label based on current state
+  defp group_filter_label_class(group_filters, group_id, expected_value) do
+    base_classes = "join-item btn btn-sm"
+    current_value = Map.get(group_filters, to_string(group_id))
+    is_active = current_value == expected_value
+
+    cond do
+      expected_value == nil ->
+        if is_active do
+          "#{base_classes} btn-active"
+        else
+          "#{base_classes} btn"
+        end
+
+      expected_value == :in ->
+        if is_active do
+          "#{base_classes} btn-success btn-active"
+        else
+          "#{base_classes} btn"
+        end
+
+      expected_value == :not_in ->
+        if is_active do
+          "#{base_classes} btn-error btn-active"
+        else
+          "#{base_classes} btn"
+        end
+
+      true ->
+        "#{base_classes} btn-outline"
+    end
+  end
+
   # Get CSS classes for boolean filter label based on current state
   defp boolean_filter_label_class(boolean_filters, custom_field_id, expected_value) do
     base_classes = "join-item btn btn-sm"

lib/mv_web/live/member_live/index.ex

@@ -41,6 +41,7 @@ defmodule MvWeb.MemberLive.Index do
 
   @custom_field_prefix Mv.Constants.custom_field_prefix()
   @boolean_filter_prefix Mv.Constants.boolean_filter_prefix()
+  @group_filter_prefix "group_"
 
   # Maximum number of boolean custom field filters allowed per request (DoS protection)
   @max_boolean_filters Mv.Constants.max_boolean_filters()
@@ -121,7 +122,7 @@ defmodule MvWeb.MemberLive.Index do
       |> assign_new(:sort_field, fn -> :first_name end)
       |> assign_new(:sort_order, fn -> :asc end)
       |> assign(:cycle_status_filter, nil)
-      |> assign(:group_filter, nil)
+      |> assign(:group_filters, %{})
       |> assign(:groups, groups)
       |> assign(:boolean_custom_field_filters, %{})
       |> assign(:selected_members, MapSet.new())
@@ -250,7 +251,7 @@ defmodule MvWeb.MemberLive.Index do
         socket.assigns.sort_field,
         socket.assigns.sort_order,
         socket.assigns.cycle_status_filter,
-        socket.assigns[:group_filter],
+        socket.assigns[:group_filters],
         new_show_current,
         socket.assigns.boolean_custom_field_filters
       )
@@ -264,35 +265,6 @@ defmodule MvWeb.MemberLive.Index do
     {:noreply, push_patch(socket, to: new_path, replace: true)}
   end
 
-  @impl true
-  def handle_event("group_filter_changed", %{"group_filter" => group_id_param}, socket) do
-    group_filter = normalize_group_filter(group_id_param, socket.assigns.groups)
-
-    socket =
-      socket
-      |> assign(:group_filter, group_filter)
-      |> load_members()
-      |> update_selection_assigns()
-
-    query_params =
-      build_query_params(
-        socket.assigns.query,
-        socket.assigns.sort_field,
-        socket.assigns.sort_order,
-        socket.assigns.cycle_status_filter,
-        group_filter,
-        socket.assigns.show_current_cycle,
-        socket.assigns.boolean_custom_field_filters
-      )
-      |> maybe_add_field_selection(
-        socket.assigns[:user_field_selection],
-        socket.assigns[:fields_in_url?] || false
-      )
-
-    new_path = ~p"/members?#{query_params}"
-    {:noreply, push_patch(socket, to: new_path, replace: true)}
-  end
-
   @impl true
   def handle_event("copy_emails", _params, socket) do
     selected_ids = socket.assigns.selected_members
@@ -390,7 +362,7 @@ defmodule MvWeb.MemberLive.Index do
         export_sort_field(socket.assigns.sort_field),
         export_sort_order(socket.assigns.sort_order),
         socket.assigns.cycle_status_filter,
-        socket.assigns[:group_filter],
+        socket.assigns[:group_filters],
         socket.assigns.show_current_cycle,
         socket.assigns.boolean_custom_field_filters
       )
@@ -416,7 +388,7 @@ defmodule MvWeb.MemberLive.Index do
         socket.assigns.sort_field,
         socket.assigns.sort_order,
         socket.assigns.cycle_status_filter,
-        socket.assigns[:group_filter],
+        socket.assigns[:group_filters],
         socket.assigns.show_current_cycle,
         socket.assigns.boolean_custom_field_filters
       )
@@ -444,7 +416,7 @@ defmodule MvWeb.MemberLive.Index do
         socket.assigns.sort_field,
         socket.assigns.sort_order,
         filter,
-        socket.assigns[:group_filter],
+        socket.assigns[:group_filters],
         socket.assigns.show_current_cycle,
         socket.assigns.boolean_custom_field_filters
       )
@@ -478,7 +450,7 @@ defmodule MvWeb.MemberLive.Index do
         socket.assigns.sort_field,
         socket.assigns.sort_order,
         socket.assigns.cycle_status_filter,
-        socket.assigns[:group_filter],
+        socket.assigns[:group_filters],
         socket.assigns.show_current_cycle,
         updated_filters
       )
@@ -491,12 +463,55 @@ defmodule MvWeb.MemberLive.Index do
     {:noreply, push_patch(socket, to: new_path, replace: true)}
   end
 
+  @impl true
+  def handle_info({:group_filter_changed, group_id_str, filter_value}, socket) do
+    normalized_id = normalize_uuid_string(group_id_str) || group_id_str
+
+    group_filters =
+      if filter_value == nil do
+        Map.delete(socket.assigns.group_filters, normalized_id)
+      else
+        Map.put(socket.assigns.group_filters, normalized_id, filter_value)
+      end
+
+    socket =
+      socket
+      |> assign(:group_filters, group_filters)
+      |> load_members()
+      |> update_selection_assigns()
+
+    query_params =
+      build_query_params(
+        socket.assigns.query,
+        socket.assigns.sort_field,
+        socket.assigns.sort_order,
+        socket.assigns.cycle_status_filter,
+        group_filters,
+        socket.assigns.show_current_cycle,
+        socket.assigns.boolean_custom_field_filters
+      )
+      |> maybe_add_field_selection(
+        socket.assigns[:user_field_selection],
+        socket.assigns[:fields_in_url?] || false
+      )
+
+    new_path = ~p"/members?#{query_params}"
+    {:noreply, push_patch(socket, to: new_path, replace: true)}
+  end
+
   @impl true
   def handle_info({:reset_all_filters, cycle_status_filter, boolean_filters}, socket) do
+    handle_info({:reset_all_filters, cycle_status_filter, boolean_filters, %{}}, socket)
+  end
+
+  def handle_info(
+        {:reset_all_filters, cycle_status_filter, boolean_filters, group_filters},
+        socket
+      ) do
     socket =
       socket
       |> assign(:cycle_status_filter, cycle_status_filter)
-      |> assign(:group_filter, nil)
+      |> assign(:group_filters, group_filters)
       |> assign(:boolean_custom_field_filters, boolean_filters)
       |> load_members()
       |> update_selection_assigns()
@@ -507,7 +522,7 @@ defmodule MvWeb.MemberLive.Index do
         socket.assigns.sort_field,
         socket.assigns.sort_order,
         cycle_status_filter,
-        socket.assigns[:group_filter],
+        socket.assigns[:group_filters],
         socket.assigns.show_current_cycle,
         boolean_filters
       )
@@ -644,7 +659,7 @@ defmodule MvWeb.MemberLive.Index do
       |> maybe_update_search(params)
       |> maybe_update_sort(params)
       |> maybe_update_cycle_status_filter(params)
-      |> maybe_update_group_filter(params)
+      |> maybe_update_group_filters(params)
       |> maybe_update_boolean_filters(params)
       |> maybe_update_show_current_cycle(params)
       |> assign(:fields_in_url?, fields_in_url?)
@@ -678,7 +693,7 @@ defmodule MvWeb.MemberLive.Index do
       socket.assigns.sort_field,
       socket.assigns.sort_order,
       socket.assigns.cycle_status_filter,
-      socket.assigns[:group_filter],
+      socket.assigns[:group_filters],
       socket.assigns.show_current_cycle,
       socket.assigns.boolean_custom_field_filters,
       socket.assigns.user_field_selection,
@@ -772,7 +787,7 @@ defmodule MvWeb.MemberLive.Index do
         socket.assigns.sort_field,
         socket.assigns.sort_order,
         socket.assigns.cycle_status_filter,
-        socket.assigns[:group_filter],
+        socket.assigns[:group_filters],
         socket.assigns.show_current_cycle,
         socket.assigns.boolean_custom_field_filters
       )
@@ -791,7 +806,7 @@ defmodule MvWeb.MemberLive.Index do
          sort_field,
          sort_order,
          cycle_status_filter,
-         group_filter,
+         group_filters,
          show_current_cycle,
          boolean_filters
        ) do
@@ -823,11 +838,10 @@ defmodule MvWeb.MemberLive.Index do
       end
 
     base_params =
-      if group_filter && group_filter != "" do
-        Map.put(base_params, "group_filter", to_string(group_filter))
-      else
-        base_params
-      end
+      Enum.reduce(group_filters, base_params, fn {group_id_str, value}, acc ->
+        param_value = if value == :in, do: "in", else: "not_in"
+        Map.put(acc, "#{@group_filter_prefix}#{group_id_str}", param_value)
+      end)
 
     base_params =
       if show_current_cycle do
@@ -884,7 +898,7 @@ defmodule MvWeb.MemberLive.Index do
 
     query = apply_search_filter(query, search_query)
 
-    query = apply_group_filter(query, socket.assigns[:group_filter])
+    query = apply_group_filters(query, socket.assigns[:group_filters], socket.assigns[:groups])
 
     # Use ALL custom fields for sorting (not just show_in_overview subset)
     custom_fields_for_sort = socket.assigns.all_custom_fields
@@ -963,13 +977,50 @@ defmodule MvWeb.MemberLive.Index do
     end
   end
 
-  defp apply_group_filter(query, nil), do: query
-  defp apply_group_filter(query, ""), do: query
+  defp apply_group_filters(query, group_filters, _groups) when group_filters == %{}, do: query
 
-  defp apply_group_filter(query, group_id) when is_binary(group_id) do
-    Ash.Query.filter(query, expr(exists(groups, id == ^group_id)))
+  defp apply_group_filters(query, group_filters, groups) do
+    valid_ids =
+      groups
+      |> Enum.map(&normalize_uuid_string(to_string(&1.id)))
+      |> Enum.reject(&is_nil/1)
+      |> MapSet.new()
+
+    Enum.reduce(group_filters, query, fn {group_id_str, value}, q ->
+      member? = MapSet.member?(valid_ids, group_id_str)
+
+      if member? do
+        apply_one_group_filter(q, group_id_str, value)
+      else
+        q
+      end
+    end)
   end
 
+  defp apply_one_group_filter(query, _group_id_str, nil), do: query
+
+  defp apply_one_group_filter(query, group_id_str, :in) do
+    case Ecto.UUID.cast(group_id_str) do
+      {:ok, group_uuid} ->
+        Ash.Query.filter(query, expr(exists(member_groups, group_id == ^group_uuid)))
+
+      _ ->
+        query
+    end
+  end
+
+  defp apply_one_group_filter(query, group_id_str, :not_in) do
+    case Ecto.UUID.cast(group_id_str) do
+      {:ok, group_uuid} ->
+        Ash.Query.filter(query, expr(not exists(member_groups, group_id == ^group_uuid)))
+
+      _ ->
+        query
+    end
+  end
+
+  defp apply_one_group_filter(query, _, _), do: query
+
   defp apply_cycle_status_filter(members, nil, _show_current), do: members
 
   defp apply_cycle_status_filter(members, status, show_current)
@@ -1097,17 +1148,15 @@ defmodule MvWeb.MemberLive.Index do
   end
 
   defp sort_members_in_memory(members, field, order, custom_fields) do
-    cond do
-      field in [:groups, "groups"] ->
-        sort_members_by_groups(members, order)
+    if field in [:groups, "groups"] do
+      sort_members_by_groups(members, order)
+    else
+      custom_field_id_str = extract_custom_field_id(field)
 
-      true ->
-        custom_field_id_str = extract_custom_field_id(field)
-
-        case custom_field_id_str do
-          nil -> members
-          id_str -> sort_members_by_custom_field(members, id_str, order, custom_fields)
-        end
+      case custom_field_id_str do
+        nil -> members
+        id_str -> sort_members_by_custom_field(members, id_str, order, custom_fields)
+      end
     end
   end
 
@@ -1223,8 +1272,12 @@ defmodule MvWeb.MemberLive.Index do
 
   defp determine_field_after_computed_check(default, sf) when is_binary(sf) do
     cond do
-      sf == "groups" -> :groups
-      custom_field_sort?(sf) -> if valid_sort_field?(sf), do: sf, else: default
+      sf == "groups" ->
+        :groups
+
+      custom_field_sort?(sf) ->
+        if valid_sort_field?(sf), do: sf, else: default
+
       true ->
         atom = safe_member_field_atom_only(sf)
         if atom != nil and valid_sort_field?(atom), do: atom, else: default
@@ -1257,31 +1310,61 @@ defmodule MvWeb.MemberLive.Index do
   defp maybe_update_cycle_status_filter(socket, _params),
     do: assign(socket, :cycle_status_filter, nil)
 
-  defp maybe_update_group_filter(socket, %{"group_filter" => group_id_param}) do
-    group_filter = normalize_group_filter(group_id_param, socket.assigns.groups)
-    assign(socket, :group_filter, group_filter)
+  defp maybe_update_group_filters(socket, params) when is_map(params) do
+    prefix = @group_filter_prefix
+    prefix_len = String.length(prefix)
+
+    group_param_entries =
+      params
+      |> Enum.filter(fn {key, _} ->
+        key_str = to_string(key)
+        String.starts_with?(key_str, prefix)
+      end)
+
+    filters =
+      Enum.reduce(group_param_entries, %{}, fn {key, value_str}, acc ->
+        add_group_filter_entry(acc, key, value_str, prefix_len)
+      end)
+
+    assign(socket, :group_filters, filters)
   end
 
-  defp maybe_update_group_filter(socket, _params), do: socket
+  defp maybe_update_group_filters(socket, _), do: socket
 
-  defp normalize_group_filter("", _groups), do: nil
-  defp normalize_group_filter(nil, _groups), do: nil
+  defp add_group_filter_entry(acc, key, value_str, prefix_len) do
+    key_str = to_string(key)
+    raw_id = String.slice(key_str, prefix_len, String.length(key_str) - prefix_len)
+    group_id_str = normalize_uuid_string(raw_id)
+    valid_id? = group_id_str && String.length(group_id_str) <= @max_uuid_length
 
-  defp normalize_group_filter(group_id_param, groups) when is_binary(group_id_param) do
-    case Ecto.UUID.cast(group_id_param) do
-      {:ok, _uuid} ->
-        if Enum.any?(groups, fn g -> to_string(g.id) == group_id_param end) do
-          group_id_param
-        else
-          nil
-        end
-
-      :error ->
-        nil
+    if valid_id? do
+      case parse_group_filter_value(value_str) do
+        nil -> acc
+        value -> Map.put(acc, group_id_str, value)
+      end
+    else
+      acc
     end
   end
 
-  defp normalize_group_filter(_, _), do: nil
+  # Normalize UUID string so URL params match valid_ids (lowercase, canonical format)
+  defp normalize_uuid_string(raw) when is_binary(raw) do
+    case Ecto.UUID.cast(String.trim(raw)) do
+      {:ok, uuid} -> to_string(uuid)
+      _ -> raw
+    end
+  end
+
+  defp normalize_uuid_string(_), do: nil
+
+  defp parse_group_filter_value("in"), do: :in
+  defp parse_group_filter_value("not_in"), do: :not_in
+
+  defp parse_group_filter_value(val) when is_binary(val) do
+    parse_group_filter_value(String.trim(val))
+  end
+
+  defp parse_group_filter_value(_), do: nil
 
   defp determine_cycle_status_filter("paid"), do: :paid
   defp determine_cycle_status_filter("unpaid"), do: :unpaid

lib/mv_web/live/member_live/index.html.heex

@@ -52,26 +52,12 @@
       query={@query}
       placeholder={gettext("Search...")}
     />
-    <form id="group-filter-form" phx-change="group_filter_changed" class="contents">
-      <select
-        name="group_filter"
-        class="select select-bordered select-sm max-w-xs"
-        aria-label={gettext("Filter by group")}
-      >
-        <option value="" selected={@group_filter == nil}>
-          {gettext("All groups")}
-        </option>
-        <%= for group <- @groups do %>
-          <option value={group.id} selected={@group_filter == to_string(group.id)}>
-            {group.name}
-          </option>
-        <% end %>
-      </select>
-    </form>
     <.live_component
       module={MvWeb.Components.MemberFilterComponent}
       id="member-filter"
       cycle_status_filter={@cycle_status_filter}
+      groups={@groups}
+      group_filters={@group_filters}
       boolean_custom_fields={@boolean_custom_fields}
       boolean_filters={@boolean_custom_field_filters}
       member_count={length(@members)}

priv/gettext/de/LC_MESSAGES/default.po

@@ -2191,7 +2191,9 @@ msgid "Group saved successfully."
 msgstr "Gruppe erfolgreich gespeichert."
 
 #: lib/mv_web/components/layouts/sidebar.ex
+#: lib/mv_web/live/components/member_filter_component.ex
 #: lib/mv_web/live/group_live/index.ex
+#: lib/mv_web/live/member_live/index.html.heex
 #, elixir-autogen, elixir-format
 msgid "Groups"
 msgstr "Gruppen"
@@ -2468,22 +2470,7 @@ msgstr "Pausiert"
 msgid "unpaid"
 msgstr "Unbezahlt"
 
-#~ #: lib/mv_web/live/global_settings_live.ex
-#~ #, elixir-autogen, elixir-format, fuzzy
-#~ msgid "Custom Fields in CSV Import"
-#~ msgstr "Benutzerdefinierte Felder"
-
-#~ #: lib/mv_web/live/global_settings_live.ex
-#~ #, elixir-autogen, elixir-format
-#~ msgid "Failed to prepare CSV import: %{error}"
-#~ msgstr "Das Vorbereiten des CSV Imports ist gescheitert: %{error}"
-
-#~ #: lib/mv_web/live/global_settings_live.ex
-#~ #, elixir-autogen, elixir-format, fuzzy
-#~ msgid "Individual data fields must be created in Mila before importing. Use the field name as the CSV column header. Unknown custom field columns will be ignored with a warning."
-#~ msgstr "Individuelle Datenfelder müssen in Mila erstellt werden, bevor sie importiert werden können. Verwende den Namen des Datenfeldes als CSV-Spaltenüberschrift. Unbekannte Spaltenüberschriften werden mit einer Warnung ignoriert."
-
-#~ #: lib/mv_web/live/member_live/show/membership_fees_component.ex
-#~ #, elixir-autogen, elixir-format
-#~ msgid "Only administrators can regenerate cycles"
-#~ msgstr "Nur Administrator*innen können Zyklen regenerieren"
+#: lib/mv_web/live/member_live/index.html.heex
+#, elixir-autogen, elixir-format
+msgid "Member of group %{name}"
+msgstr "Mitglied der Gruppe %{name}"

priv/gettext/default.pot

@@ -2192,7 +2192,9 @@ msgid "Group saved successfully."
 msgstr ""
 
 #: lib/mv_web/components/layouts/sidebar.ex
+#: lib/mv_web/live/components/member_filter_component.ex
 #: lib/mv_web/live/group_live/index.ex
+#: lib/mv_web/live/member_live/index.html.heex
 #, elixir-autogen, elixir-format
 msgid "Groups"
 msgstr ""
@@ -2468,3 +2470,8 @@ msgstr ""
 #, elixir-autogen, elixir-format
 msgid "unpaid"
 msgstr ""
+
+#: lib/mv_web/live/member_live/index.html.heex
+#, elixir-autogen, elixir-format
+msgid "Member of group %{name}"
+msgstr ""

priv/gettext/en/LC_MESSAGES/default.po

@@ -13,6 +13,7 @@ msgstr ""
 
 #: lib/mv_web/components/core_components.ex
 #: lib/mv_web/live/group_live/index.ex
+#: lib/mv_web/live/group_live/show.ex
 #, elixir-autogen, elixir-format
 msgid "Actions"
 msgstr ""
@@ -671,6 +672,7 @@ msgstr ""
 msgid "A member with this email already exists. To link with a different member, please change one of the email addresses first."
 msgstr ""
 
+#: lib/mv_web/live/group_live/show.ex
 #: lib/mv_web/live/user_live/form.ex
 #, elixir-autogen, elixir-format
 msgid "Available members"
@@ -2190,7 +2192,9 @@ msgid "Group saved successfully."
 msgstr ""
 
 #: lib/mv_web/components/layouts/sidebar.ex
+#: lib/mv_web/live/components/member_filter_component.ex
 #: lib/mv_web/live/group_live/index.ex
+#: lib/mv_web/live/member_live/index.html.heex
 #, elixir-autogen, elixir-format
 msgid "Groups"
 msgstr ""
@@ -2254,6 +2258,66 @@ msgstr ""
 msgid "Could not load member search. Please try again."
 msgstr ""
 
+#: lib/mv_web/live/group_live/show.ex
+#, elixir-autogen, elixir-format, fuzzy
+msgid "Add Member"
+msgstr ""
+
+#: lib/mv_web/live/group_live/show.ex
+#, elixir-autogen, elixir-format, fuzzy
+msgid "Failed to remove member: %{error}"
+msgstr ""
+
+#: lib/mv_web/live/group_live/show.ex
+#, elixir-autogen, elixir-format
+msgid "Member is not in this group."
+msgstr ""
+
+#: lib/mv_web/live/group_live/show.ex
+#, elixir-autogen, elixir-format, fuzzy
+msgid "No email"
+msgstr ""
+
+#: lib/mv_web/live/group_live/show.ex
+#, elixir-autogen, elixir-format
+msgid "Remove"
+msgstr ""
+
+#: lib/mv_web/live/group_live/show.ex
+#, elixir-autogen, elixir-format
+msgid "Remove member from group"
+msgstr ""
+
+#: lib/mv_web/live/group_live/show.ex
+#, elixir-autogen, elixir-format, fuzzy
+msgid "Search for a member"
+msgstr ""
+
+#: lib/mv_web/live/group_live/show.ex
+#, elixir-autogen, elixir-format, fuzzy
+msgid "Search for a member..."
+msgstr ""
+
+#: lib/mv_web/live/group_live/show.ex
+#, elixir-autogen, elixir-format
+msgid "Add members"
+msgstr ""
+
+#: lib/mv_web/live/group_live/show.ex
+#, elixir-autogen, elixir-format, fuzzy
+msgid "No members selected."
+msgstr ""
+
+#: lib/mv_web/live/group_live/show.ex
+#, elixir-autogen, elixir-format
+msgid "Remove %{name}"
+msgstr ""
+
+#: lib/mv_web/live/group_live/show.ex
+#, elixir-autogen, elixir-format
+msgid "Some members could not be added: %{errors}"
+msgstr ""
+
 #: lib/mv_web/live/import_export_live/components.ex
 #, elixir-autogen, elixir-format, fuzzy
 msgid "CSV files only, maximum %{size} MB"
@@ -2407,22 +2471,7 @@ msgstr ""
 msgid "unpaid"
 msgstr ""
 
-#~ #: lib/mv_web/live/global_settings_live.ex
-#~ #, elixir-autogen, elixir-format, fuzzy
-#~ msgid "Custom Fields in CSV Import"
-#~ msgstr ""
-
-#~ #: lib/mv_web/live/global_settings_live.ex
-#~ #, elixir-autogen, elixir-format
-#~ msgid "Failed to prepare CSV import: %{error}"
-#~ msgstr ""
-
-#~ #: lib/mv_web/live/global_settings_live.ex
-#~ #, elixir-autogen, elixir-format, fuzzy
-#~ msgid "Individual data fields must be created in Mila before importing. Use the field name as the CSV column header. Unknown custom field columns will be ignored with a warning."
-#~ msgstr ""
-
-#~ #: lib/mv_web/live/member_live/show/membership_fees_component.ex
-#~ #, elixir-autogen, elixir-format
-#~ msgid "Only administrators can regenerate cycles"
-#~ msgstr ""
+#: lib/mv_web/live/member_live/index.html.heex
+#, elixir-autogen, elixir-format
+msgid "Member of group %{name}"
+msgstr ""

test/mv_web/member_live/index_groups_accessibility_test.exs

@@ -62,18 +62,21 @@ defmodule MvWeb.MemberLive.IndexGroupsAccessibilityTest do
   end
 
   @tag :ui
-  test "filter dropdown has aria-label", %{
+  test "filter dropdown has group presence section with legend", %{
     conn: conn
   } do
     conn = conn_with_oidc_user(conn)
-    {:ok, view, html} = live(conn, "/members")
+    {:ok, view, _html} = live(conn, "/members")
 
-    # Verify filter dropdown has aria-label
-    assert html =~ ~r/select.*name=["']group_filter["'].*aria-label=/ or
-             html =~ ~r/aria-label=.*[Gg]roup/
+    # Open filter dropdown
+    view
+    |> element("button[aria-label='Filter members']")
+    |> render_click()
 
-    # Verify dropdown is present
-    assert has_element?(view, "select[name='group_filter']")
+    html = render(view)
+    # Groups section: legend "Member has groups" and radios (Any / Yes / No)
+    assert html =~ ~r/[Gg]roups/
+    assert has_element?(view, "[data-testid='member-filter-form']")
   end
 
   @tag :ui
@@ -92,26 +95,22 @@ defmodule MvWeb.MemberLive.IndexGroupsAccessibilityTest do
   @tag :ui
   test "keyboard navigation works for filter dropdown", %{
     conn: conn,
+    member1: member1,
     group1: group1
   } do
     conn = conn_with_oidc_user(conn)
     {:ok, view, _html} = live(conn, "/members")
 
-    # Verify dropdown is keyboard accessible
-    # Tab should focus the dropdown
-    # Arrow keys should navigate options
-    # Enter should select option
-    assert has_element?(view, "select[name='group_filter']")
-
-    # Test that dropdown can be focused and changed via keyboard
-    # (This is a basic accessibility check - actual keyboard testing would require browser automation)
     view
-    |> element("#group-filter-form")
-    |> render_change(%{"group_filter" => group1.id})
+    |> element("button[aria-label='Filter members']")
+    |> render_click()
+
+    view
+    |> element("[data-testid='member-filter-form']")
+    |> render_change(%{"group_#{group1.id}" => "in", "payment_filter" => "all"})
 
-    # Verify change was applied
     html = render(view)
-    assert html
+    assert html =~ member1.first_name
   end
 
   @tag :ui
@@ -121,18 +120,14 @@ defmodule MvWeb.MemberLive.IndexGroupsAccessibilityTest do
     conn = conn_with_oidc_user(conn)
     {:ok, view, _html} = live(conn, "/members")
 
-    # Verify sort header is keyboard accessible
-    # Tab should focus the sort header
-    # Enter/Space should activate sorting
     assert has_element?(view, "[data-testid='groups']")
 
-    # Test that sort header can be activated via click (simulating keyboard)
     view
     |> element("[data-testid='groups']")
     |> render_click()
 
-    # Verify sort was applied
-    assert_patch(view, "/members?query=&sort_field=groups&sort_order=asc")
+    # Verify sort was applied (URL may include other params)
+    assert has_element?(view, "[data-testid='groups'][aria-label*='ascending']")
   end
 
   @tag :ui
@@ -144,19 +139,16 @@ defmodule MvWeb.MemberLive.IndexGroupsAccessibilityTest do
     conn = conn_with_oidc_user(conn)
     {:ok, view, _html} = live(conn, "/members")
 
-    # Apply filter
     view
-    |> element("#group-filter-form")
-    |> render_change(%{"group_filter" => group1.id})
+    |> element("button[aria-label='Filter members']")
+    |> render_click()
+
+    view
+    |> element("[data-testid='member-filter-form']")
+    |> render_change(%{"group_#{group1.id}" => "in", "payment_filter" => "all"})
 
-    # Verify filter change is announced (via aria-live region or similar)
     html = render(view)
-    # Should show filtered results
     assert html =~ member1.first_name
-
-    # Verify member count or filter status is announced
-    # (Implementation might use aria-live="polite" for announcements)
-    assert html
   end
 
   @tag :ui

test/mv_web/member_live/index_groups_display_test.exs

@@ -64,7 +64,11 @@ defmodule MvWeb.MemberLive.IndexGroupsDisplayTest do
     %{member1: member1, member2: member2, member3: member3, group1: group1, group2: group2}
   end
 
-  test "displays group badges for members in groups", %{conn: conn, group1: group1, group2: group2} do
+  test "displays group badges for members in groups", %{
+    conn: conn,
+    group1: group1,
+    group2: group2
+  } do
     conn = conn_with_oidc_user(conn)
     {:ok, _view, html} = live(conn, "/members")
 

test/mv_web/member_live/index_groups_filter_test.exs

@@ -1,6 +1,9 @@
 defmodule MvWeb.MemberLive.IndexGroupsFilterTest do
   @moduledoc """
   Tests for filtering members by group in the member overview.
+
+  Uses the filter dropdown (MemberFilterComponent) with one row per group:
+  All / Yes / No (per group).
   """
   # async: false to prevent PostgreSQL deadlocks when creating members and groups
   use MvWeb.ConnCase, async: false
@@ -53,7 +56,28 @@ defmodule MvWeb.MemberLive.IndexGroupsFilterTest do
     %{member1: member1, member2: member2, member3: member3, group1: group1, group2: group2}
   end
 
-  test "filter 'All groups' shows all members", %{conn: conn, member1: m1, member2: m2, member3: m3} do
+  defp open_filter_and_set_group(view, group_id, value) do
+    view
+    |> element("button[aria-label='Filter members']")
+    |> render_click()
+
+    key = "group_#{group_id}"
+
+    view
+    |> element("[data-testid='member-filter-form']")
+    |> render_change(%{key => value, "payment_filter" => "all"})
+
+    # Force LiveView to process {:group_filter_changed, ...} (render triggers mailbox processing)
+    _ = render(view)
+    assert_patch(view)
+  end
+
+  test "filter All (default) shows all members", %{
+    conn: conn,
+    member1: m1,
+    member2: m2,
+    member3: m3
+  } do
     conn = conn_with_oidc_user(conn)
     {:ok, _view, html} = live(conn, "/members")
     assert html =~ m1.first_name
@@ -61,7 +85,7 @@ defmodule MvWeb.MemberLive.IndexGroupsFilterTest do
     assert html =~ m3.first_name
   end
 
-  test "filter by specific group shows only members in that group", %{
+  test "filter group1 Yes shows only members in group1", %{
     conn: conn,
     member1: m1,
     member2: m2,
@@ -71,9 +95,7 @@ defmodule MvWeb.MemberLive.IndexGroupsFilterTest do
     conn = conn_with_oidc_user(conn)
     {:ok, view, _html} = live(conn, "/members")
 
-    view
-    |> element("#group-filter-form")
-    |> render_change(%{"group_filter" => group1.id})
+    open_filter_and_set_group(view, group1.id, "in")
 
     html = render(view)
     assert html =~ m1.first_name
@@ -81,21 +103,45 @@ defmodule MvWeb.MemberLive.IndexGroupsFilterTest do
     refute html =~ m3.first_name
   end
 
-  test "filter persists in URL parameters", %{conn: conn, group1: group1, member1: m1} do
+  test "filter group1 No shows only members not in group1", %{
+    conn: conn,
+    member1: m1,
+    member2: m2,
+    member3: m3,
+    group1: group1
+  } do
     conn = conn_with_oidc_user(conn)
     {:ok, view, _html} = live(conn, "/members")
 
-    view
-    |> element("#group-filter-form")
-    |> render_change(%{"group_filter" => group1.id})
+    open_filter_and_set_group(view, group1.id, "not_in")
+
+    html = render(view)
+    refute html =~ m1.first_name
+    assert html =~ m2.first_name
+    assert html =~ m3.first_name
+  end
+
+  test "filter persists in URL parameters", %{
+    conn: conn,
+    member1: m1,
+    member2: m2,
+    member3: m3,
+    group1: group1
+  } do
+    conn = conn_with_oidc_user(conn)
+    {:ok, view, _html} = live(conn, "/members")
+
+    open_filter_and_set_group(view, group1.id, "in")
 
-    # Verify filter is applied
     html = render(view)
     assert html =~ m1.first_name
+    refute html =~ m2.first_name
+    refute html =~ m3.first_name
 
-    # Verify visiting with group_filter in URL shows same filtered list
-    {:ok, _view2, html2} = live(conn, "/members?group_filter=#{group1.id}")
+    {:ok, _view2, html2} = live(conn, "/members?group_#{group1.id}=in")
     assert html2 =~ m1.first_name
+    refute html2 =~ m2.first_name
+    refute html2 =~ m3.first_name
   end
 
   test "filter is restored from URL on load", %{
@@ -106,7 +152,7 @@ defmodule MvWeb.MemberLive.IndexGroupsFilterTest do
     group1: group1
   } do
     conn = conn_with_oidc_user(conn)
-    {:ok, _view, html} = live(conn, "/members?group_filter=#{group1.id}")
+    {:ok, _view, html} = live(conn, "/members?group_#{group1.id}=in")
     assert html =~ m1.first_name
     refute html =~ m2.first_name
     refute html =~ m3.first_name

test/mv_web/member_live/index_groups_integration_test.exs

@@ -102,8 +102,12 @@ defmodule MvWeb.MemberLive.IndexGroupsIntegrationTest do
     {:ok, view, _html} = live(conn, "/members")
 
     view
-    |> element("#group-filter-form")
-    |> render_change(%{"group_filter" => group1.id})
+    |> element("button[aria-label='Filter members']")
+    |> render_click()
+
+    view
+    |> element("[data-testid='member-filter-form']")
+    |> render_change(%{"group_#{group1.id}" => "in", "payment_filter" => "all"})
 
     html = render(view)
     assert html =~ member1.first_name
@@ -160,13 +164,13 @@ defmodule MvWeb.MemberLive.IndexGroupsIntegrationTest do
       |> Ash.create(actor: system_actor)
 
     conn = conn_with_oidc_user(conn)
-    # Visit with both group filter and cycle status filter in URL (cycle filter is toggled via button, not a select).
-    # Cycle filter may depend on "current" cycle; we only verify the page loads with both params.
+
     {:ok, _view, html} =
-      live(conn, "/members?group_filter=#{group1.id}&cycle_status_filter=paid")
+      live(conn, "/members?group_#{group1.id}=in&cycle_status_filter=paid")
 
     assert html =~ "Members"
-    assert html =~ group1.name
+    # member1 has a group and a paid cycle; page should load with both filters
+    assert html =~ member1.first_name
   end
 
   test "groups work with existing search (not testing search integration)", %{
@@ -180,8 +184,12 @@ defmodule MvWeb.MemberLive.IndexGroupsIntegrationTest do
 
     # Apply group filter
     view
-    |> element("#group-filter-form")
-    |> render_change(%{"group_filter" => group1.id})
+    |> element("button[aria-label='Filter members']")
+    |> render_click()
+
+    view
+    |> element("[data-testid='member-filter-form']")
+    |> render_change(%{"group_#{group1.id}" => "in", "payment_filter" => "all"})
 
     # Apply search (this tests that filter and search work together;
     # search form is in SearchBarComponent with phx-submit="search")
@@ -208,8 +216,12 @@ defmodule MvWeb.MemberLive.IndexGroupsIntegrationTest do
 
     # Apply group filter
     view
-    |> element("#group-filter-form")
-    |> render_change(%{"group_filter" => group1.id})
+    |> element("button[aria-label='Filter members']")
+    |> render_click()
+
+    view
+    |> element("[data-testid='member-filter-form']")
+    |> render_change(%{"group_#{group1.id}" => "in", "payment_filter" => "all"})
 
     # Apply sorting
     view

test/mv_web/member_live/index_groups_performance_test.exs

@@ -97,30 +97,28 @@ defmodule MvWeb.MemberLive.IndexGroupsPerformanceTest do
     conn = conn_with_oidc_user(conn)
     {:ok, view, _html} = live(conn, "/members")
 
-    # Apply filter
+    # Open filter and apply "Yes" for group1 (even-indexed members are in group1)
     view
-    |> element("#group-filter-form")
-    |> render_change(%{"group_filter" => group1.id})
+    |> element("button[aria-label='Filter members']")
+    |> render_click()
 
-    # Verify only filtered members are shown
+    view
+    |> element("[data-testid='member-filter-form']")
+    |> render_change(%{"group_#{group1.id}" => "in", "payment_filter" => "all"})
+
+    # Force LiveView to process {:group_filter_changed, ...}
     html = render(view)
 
-    # Members with even indices (0, 2, 4, 6, 8) are in group1
-    even_members = Enum.filter(0..9, &(rem(&1, 2) == 0))
-    odd_members = Enum.filter(0..9, &(rem(&1, 2) == 1))
-
-    Enum.each(even_members, fn i ->
+    # Only even-indexed members (0,2,4,6,8) are in group1
+    Enum.each([0, 2, 4, 6, 8], fn i ->
       member = Enum.at(members, i)
       assert html =~ member.first_name
     end)
 
-    Enum.each(odd_members, fn i ->
+    Enum.each([1, 3, 5, 7, 9], fn i ->
       member = Enum.at(members, i)
       refute html =~ member.first_name
     end)
-
-    # If filtering was done in-memory, we'd load all members first
-    # Database-level filtering is more efficient
   end
 
   @tag :slow

test/mv_web/member_live/index_groups_url_params_test.exs

@@ -3,7 +3,7 @@ defmodule MvWeb.MemberLive.IndexGroupsUrlParamsTest do
   Tests for URL parameter persistence for groups in the member overview.
 
   Tests cover:
-  - Group filter is written to URL (group_filter=<group_id>)
+  - Group presence filter is written to URL (group_presence=has_groups|no_groups)
   - Group sorting is written to URL (sort_field=groups&sort_order=asc)
   - URL parameters are restored on load
   - URL parameters work with other parameters (query, sort_field, etc.)
@@ -53,19 +53,22 @@ defmodule MvWeb.MemberLive.IndexGroupsUrlParamsTest do
 
   test "group filter is written to URL", %{
     conn: conn,
+    member1: member1,
     group1: group1
   } do
     conn = conn_with_oidc_user(conn)
     {:ok, view, _html} = live(conn, "/members")
 
-    # Apply group filter
     view
-    |> element("#group-filter-form")
-    |> render_change(%{"group_filter" => group1.id})
+    |> element("button[aria-label='Filter members']")
+    |> render_click()
+
+    view
+    |> element("[data-testid='member-filter-form']")
+    |> render_change(%{"group_#{group1.id}" => "in", "payment_filter" => "all"})
 
-    # Verify filter was applied (URL is patched with group_filter and other default params)
     html = render(view)
-    assert html =~ group1.name
+    assert html =~ member1.first_name
   end
 
   test "group sorting is written to URL", %{
@@ -92,13 +95,10 @@ defmodule MvWeb.MemberLive.IndexGroupsUrlParamsTest do
     conn = conn_with_oidc_user(conn)
 
     {:ok, view, html} =
-      live(conn, "/members?group_filter=#{group1.id}&sort_field=groups&sort_order=asc")
+      live(conn, "/members?group_#{group1.id}=in&sort_field=groups&sort_order=asc")
 
-    # Verify filter is applied
     assert html =~ member1.first_name
     refute html =~ member2.first_name
-
-    # Verify sort is applied
     assert has_element?(view, "[data-testid='groups'][aria-label*='ascending']")
   end
 
@@ -108,23 +108,22 @@ defmodule MvWeb.MemberLive.IndexGroupsUrlParamsTest do
     group1: group1
   } do
     conn = conn_with_oidc_user(conn)
-    {:ok, view, html} = live(conn, "/members?query=Alice&group_filter=#{group1.id}")
+    {:ok, _view, html} = live(conn, "/members?query=Alice&group_#{group1.id}=in")
 
-    # Verify both query and filter are applied (URL may include other default params)
     assert html =~ member1.first_name
   end
 
   test "URL parameters work with other sort fields", %{
     conn: conn,
+    member1: member1,
     group1: group1
   } do
     conn = conn_with_oidc_user(conn)
 
     {:ok, view, html} =
-      live(conn, "/members?sort_field=first_name&sort_order=desc&group_filter=#{group1.id}")
+      live(conn, "/members?sort_field=first_name&sort_order=desc&group_#{group1.id}=in")
 
-    # Verify all parameters are preserved (filter applied, sort reflected in UI)
-    assert html =~ group1.name
+    assert html =~ member1.first_name
     assert has_element?(view, "[data-testid='first_name'][aria-label*='descending']")
   end
 
@@ -134,37 +133,28 @@ defmodule MvWeb.MemberLive.IndexGroupsUrlParamsTest do
     group1: group1
   } do
     conn = conn_with_oidc_user(conn)
-    # Simulate bookmarking a URL with filter and sort
-    bookmark_url = "/members?group_filter=#{group1.id}&sort_field=groups&sort_order=asc"
+    bookmark_url = "/members?group_#{group1.id}=in&sort_field=groups&sort_order=asc"
 
     {:ok, view, html} = live(conn, bookmark_url)
 
-    # Verify filter and sort are both applied when loading bookmarked URL
     assert html =~ member1.first_name
     assert has_element?(view, "[data-testid='groups'][aria-label*='ascending']")
   end
 
-  test "handles multiple group_filter parameters (uses last one)", %{
+  test "handles multiple group filter parameters (uses last one)", %{
     conn: conn,
+    member1: member1,
+    member2: member2,
     group1: group1
   } do
-    system_actor = Mv.Helpers.SystemActor.get_system_actor()
-
-    {:ok, group2} =
-      Group
-      |> Ash.Changeset.for_create(:create, %{name: "Active Members"})
-      |> Ash.create(actor: system_actor)
-
     conn = conn_with_oidc_user(conn)
-    # URL with duplicate parameters (should use last one)
-    {:ok, view, _html} =
-      live(conn, "/members?group_filter=#{group1.id}&group_filter=#{group2.id}")
+    # Duplicate param for same group: last wins. group_id=in then not_in -> not_in
+    {:ok, _view, html} =
+      live(conn, "/members?group_#{group1.id}=in&group_#{group1.id}=not_in")
 
-    # Verify the last filter value is used
-    # Implementation should handle this gracefully
-    html = render(view)
-    # Should show members from group2 (last filter)
-    assert html
+    # not_in group1: member2 and member3 (member1 is in group1)
+    refute html =~ member1.first_name
+    assert html =~ member2.first_name
   end
 
   test "handles invalid URL parameters gracefully", %{
@@ -173,11 +163,10 @@ defmodule MvWeb.MemberLive.IndexGroupsUrlParamsTest do
     member2: member2
   } do
     conn = conn_with_oidc_user(conn)
-    # URL with invalid group_filter (non-existent UUID)
     invalid_id = Ecto.UUID.generate()
-    {:ok, view, html} = live(conn, "/members?group_filter=#{invalid_id}")
+    {:ok, _view, html} = live(conn, "/members?group_#{invalid_id}=in")
 
-    # Verify all members are shown (invalid filter ignored)
+    # Unknown group id ignored, all members shown
     assert html =~ member1.first_name
     assert html =~ member2.first_name
   end
@@ -188,10 +177,8 @@ defmodule MvWeb.MemberLive.IndexGroupsUrlParamsTest do
     member2: member2
   } do
     conn = conn_with_oidc_user(conn)
-    # URL with malformed group_filter (not a UUID)
-    {:ok, view, html} = live(conn, "/members?group_filter=not-a-uuid")
+    {:ok, _view, html} = live(conn, "/members?group_not-a-uuid=in")
 
-    # Verify all members are shown (malformed filter ignored)
     assert html =~ member1.first_name
     assert html =~ member2.first_name
   end