Merge pull request 'Custom Fields: Handle Deletion of custom fields, closes #199' (#206) from feature/custom-field-deletion into main

Reviewed-on: #206
Reviewed-by: carla <carla@noreply.git.local-it.org>

lib/membership/custom_field.ex

@@ -28,7 +28,10 @@ defmodule Mv.Membership.CustomField do
   ## Constraints
   - Name must be unique across all custom fields
   - Name maximum length: 100 characters
-  - Cannot delete a custom field that has existing custom field values (RESTRICT)
+  - Deleting a custom field will cascade delete all associated custom field values
+
+  ## Calculations
+  - `assigned_members_count` - Returns the number of distinct members with values for this custom field
 
   ## Examples
       # Create a new custom field
@@ -55,7 +58,7 @@ defmodule Mv.Membership.CustomField do
   end
 
   actions do
-    defaults [:read, :update, :destroy]
+    defaults [:read, :update]
     default_accept [:name, :value_type, :description, :immutable, :required]
 
     create :create do
@@ -63,6 +66,17 @@ defmodule Mv.Membership.CustomField do
       change Mv.Membership.CustomField.Changes.GenerateSlug
       validate string_length(:slug, min: 1)
     end
+
+    destroy :destroy_with_values do
+      primary? true
+    end
+
+    read :prepare_deletion do
+      argument :id, :uuid, allow_nil?: false
+
+      filter expr(id == ^arg(:id))
+      prepare build(load: [:assigned_members_count])
+    end
   end
 
   attributes do
@@ -111,6 +125,17 @@ defmodule Mv.Membership.CustomField do
     has_many :custom_field_values, Mv.Membership.CustomFieldValue
   end
 
+  calculations do
+    calculate :assigned_members_count,
+              :integer,
+              expr(
+                fragment(
+                  "(SELECT COUNT(DISTINCT member_id) FROM custom_field_values WHERE custom_field_id = ?)",
+                  id
+                )
+              )
+  end
+
   identities do
     identity :unique_name, [:name]
     identity :unique_slug, [:slug]

lib/membership/custom_field_value.ex

@@ -25,11 +25,12 @@ defmodule Mv.Membership.CustomFieldValue do
 
   ## Relationships
   - `belongs_to :member` - The member this custom field value belongs to (CASCADE delete)
-  - `belongs_to :custom_field` - The custom field definition
+  - `belongs_to :custom_field` - The custom field definition (CASCADE delete)
 
   ## Constraints
   - Each member can have only one custom field value per custom field (unique composite index)
   - Custom field values are deleted when the associated member is deleted (CASCADE)
+  - Custom field values are deleted when the associated custom field is deleted (CASCADE)
   - String values maximum length: 10,000 characters
   - Email values maximum length: 254 characters (RFC 5321)
 
@@ -46,12 +47,19 @@ defmodule Mv.Membership.CustomFieldValue do
 
     references do
       reference :member, on_delete: :delete
+      reference :custom_field, on_delete: :delete
     end
   end
 
   actions do
     defaults [:create, :read, :update, :destroy]
     default_accept [:value, :member_id, :custom_field_id]
+
+    read :by_custom_field_id do
+      argument :custom_field_id, :uuid, allow_nil?: false
+
+      filter expr(custom_field_id == ^arg(:custom_field_id))
+    end
   end
 
   attributes do

lib/membership/membership.ex

@@ -42,7 +42,8 @@ defmodule Mv.Membership do
       define :create_custom_field, action: :create
       define :list_custom_fields, action: :read
       define :update_custom_field, action: :update
-      define :destroy_custom_field, action: :destroy
+      define :destroy_custom_field, action: :destroy_with_values
+      define :prepare_custom_field_deletion, action: :prepare_deletion, args: [:id]
     end
   end
 end

lib/mv_web/live/custom_field_live/index.ex

@@ -8,7 +8,7 @@ defmodule MvWeb.CustomFieldLive.Index do
   - Show immutable and required flags
   - Create new custom fields
   - Edit existing custom fields
-  - Delete custom fields (if no custom field values use them)
+  - Delete custom fields with confirmation (cascades to all custom field values)
 
   ## Displayed Information
   - Name: Unique identifier for the custom field
@@ -18,10 +18,14 @@ defmodule MvWeb.CustomFieldLive.Index do
   - Required: Whether all members must have this custom field (future feature)
 
   ## Events
-  - `delete` - Remove a custom field (only if no custom field values exist)
+  - `prepare_delete` - Opens deletion confirmation modal with member count
+  - `confirm_delete` - Executes deletion after slug verification
+  - `cancel_delete` - Cancels deletion and closes modal
+  - `update_slug_confirmation` - Updates slug input state
 
   ## Security
   Custom field management is restricted to admin users.
+  Deletion requires entering the custom field's slug to prevent accidental deletions.
   """
   use MvWeb, :live_view
 
@@ -55,15 +59,76 @@ defmodule MvWeb.CustomFieldLive.Index do
           <.link navigate={~p"/custom_fields/#{custom_field}/edit"}>Edit</.link>
         </:action>
 
-        <:action :let={{id, custom_field}}>
+        <:action :let={{_id, custom_field}}>
-          <.link
+          <.link phx-click={JS.push("prepare_delete", value: %{id: custom_field.id})}>
-            phx-click={JS.push("delete", value: %{id: custom_field.id}) |> hide("##{id}")}
-            data-confirm="Are you sure?"
-          >
             Delete
           </.link>
         </:action>
       </.table>
+
+      <%!-- Delete Confirmation Modal --%>
+      <dialog :if={@show_delete_modal} id="delete-custom-field-modal" class="modal modal-open">
+        <div class="modal-box">
+          <h3 class="font-bold text-lg">{gettext("Delete Custom Field")}</h3>
+
+          <div class="py-4 space-y-4">
+            <div class="alert alert-warning">
+              <.icon name="hero-exclamation-triangle" class="h-5 w-5" />
+              <div>
+                <p class="font-semibold">
+                  {ngettext(
+                    "%{count} member has a value assigned for this custom field.",
+                    "%{count} members have values assigned for this custom field.",
+                    @custom_field_to_delete.assigned_members_count,
+                    count: @custom_field_to_delete.assigned_members_count
+                  )}
+                </p>
+                <p class="text-sm mt-2">
+                  {gettext(
+                    "All custom field values will be permanently deleted when you delete this custom field."
+                  )}
+                </p>
+              </div>
+            </div>
+
+            <div>
+              <label for="slug-confirmation" class="label">
+                <span class="label-text">
+                  {gettext("To confirm deletion, please enter this text:")}
+                </span>
+              </label>
+              <div class="font-mono font-bold text-lg mb-2 p-2 bg-base-200 rounded break-all">
+                {@custom_field_to_delete.slug}
+              </div>
+              <form phx-change="update_slug_confirmation">
+                <input
+                  id="slug-confirmation"
+                  name="slug"
+                  type="text"
+                  value={@slug_confirmation}
+                  placeholder={gettext("Enter the text above to confirm")}
+                  autocomplete="off"
+                  phx-mounted={JS.focus()}
+                  class="input input-bordered w-full"
+                />
+              </form>
+            </div>
+          </div>
+
+          <div class="modal-action">
+            <button phx-click="cancel_delete" class="btn">
+              {gettext("Cancel")}
+            </button>
+            <button
+              phx-click="confirm_delete"
+              class="btn btn-error"
+              disabled={@slug_confirmation != @custom_field_to_delete.slug}
+            >
+              {gettext("Delete Custom Field and All Values")}
+            </button>
+          </div>
+        </div>
+      </dialog>
     </Layouts.app>
     """
   end
@@ -73,14 +138,62 @@ defmodule MvWeb.CustomFieldLive.Index do
     {:ok,
      socket
      |> assign(:page_title, "Listing Custom fields")
+     |> assign(:show_delete_modal, false)
+     |> assign(:custom_field_to_delete, nil)
+     |> assign(:slug_confirmation, "")
      |> stream(:custom_fields, Ash.read!(Mv.Membership.CustomField))}
   end
 
   @impl true
-  def handle_event("delete", %{"id" => id}, socket) do
+  def handle_event("prepare_delete", %{"id" => id}, socket) do
-    custom_field = Ash.get!(Mv.Membership.CustomField, id)
+    custom_field = Ash.get!(Mv.Membership.CustomField, id, load: [:assigned_members_count])
-    Ash.destroy!(custom_field)
 
-    {:noreply, stream_delete(socket, :custom_fields, custom_field)}
+    {:noreply,
+     socket
+     |> assign(:custom_field_to_delete, custom_field)
+     |> assign(:show_delete_modal, true)
+     |> assign(:slug_confirmation, "")}
+  end
+
+  @impl true
+  def handle_event("update_slug_confirmation", %{"slug" => slug}, socket) do
+    {:noreply, assign(socket, :slug_confirmation, slug)}
+  end
+
+  @impl true
+  def handle_event("confirm_delete", _params, socket) do
+    custom_field = socket.assigns.custom_field_to_delete
+
+    if socket.assigns.slug_confirmation == custom_field.slug do
+      # Delete the custom field (CASCADE will handle custom field values)
+      case Ash.destroy(custom_field) do
+        :ok ->
+          {:noreply,
+           socket
+           |> put_flash(:info, "Custom field deleted successfully")
+           |> assign(:show_delete_modal, false)
+           |> assign(:custom_field_to_delete, nil)
+           |> assign(:slug_confirmation, "")
+           |> stream_delete(:custom_fields, custom_field)}
+
+        {:error, error} ->
+          {:noreply,
+           socket
+           |> put_flash(:error, "Failed to delete custom field: #{inspect(error)}")}
+      end
+    else
+      {:noreply,
+       socket
+       |> put_flash(:error, "Slug does not match. Deletion cancelled.")}
+    end
+  end
+
+  @impl true
+  def handle_event("cancel_delete", _params, socket) do
+    {:noreply,
+     socket
+     |> assign(:show_delete_modal, false)
+     |> assign(:custom_field_to_delete, nil)
+     |> assign(:slug_confirmation, "")}
   end
 end

priv/gettext/de/LC_MESSAGES/default.po

@@ -253,6 +253,7 @@ msgid "Your password has successfully been reset"
 msgstr "Ihr Passwort wurde erfolgreich zurückgesetzt"
 
 #: lib/mv_web/live/custom_field_live/form.ex:67
+#: lib/mv_web/live/custom_field_live/index.ex:120
 #: lib/mv_web/live/custom_field_value_live/form.ex:77
 #: lib/mv_web/live/member_live/form.ex:82
 #: lib/mv_web/live/user_live/form.ex:127
@@ -659,4 +660,41 @@ msgstr "Verwende dieses Formular, um Benutzerdefinierte Feldwerte in deiner Date
 #: lib/mv_web/live/custom_field_live/show.ex:56
 #, elixir-autogen, elixir-format
 msgid "Auto-generated identifier (immutable)"
-msgstr "Automatisch generierter Identifier"
+msgstr "Automatisch generierter Bezeichner (unveränderlich)"
+
+#: lib/mv_web/live/custom_field_live/index.ex:79
+#, elixir-autogen, elixir-format
+msgid "%{count} member has a value assigned for this custom field."
+msgid_plural "%{count} members have values assigned for this custom field."
+msgstr[0] "%{count} Mitglied hat einen Wert für dieses benutzerdefinierte Feld zugewiesen."
+msgstr[1] "%{count} Mitglieder haben Werte für dieses benutzerdefinierte Feld zugewiesen."
+
+#: lib/mv_web/live/custom_field_live/index.ex:87
+#, elixir-autogen, elixir-format
+msgid "All custom field values will be permanently deleted when you delete this custom field."
+msgstr "Alle benutzerdefinierten Feldwerte werden beim Löschen dieses benutzerdefinierten Feldes dauerhaft gelöscht."
+
+#: lib/mv_web/live/custom_field_live/index.ex:72
+#, elixir-autogen, elixir-format
+msgid "Delete Custom Field"
+msgstr "Benutzerdefiniertes Feld löschen"
+
+#: lib/mv_web/live/custom_field_live/index.ex:127
+#, elixir-autogen, elixir-format
+msgid "Delete Custom Field and All Values"
+msgstr "Benutzerdefiniertes Feld und alle Werte löschen"
+
+#: lib/mv_web/live/custom_field_live/index.ex:109
+#, elixir-autogen, elixir-format
+msgid "Enter the text above to confirm"
+msgstr "Obigen Text zur Bestätigung eingeben"
+
+#: lib/mv_web/live/custom_field_live/index.ex:97
+#, elixir-autogen, elixir-format, fuzzy
+msgid "To confirm deletion, please enter this text:"
+msgstr "Um die Löschung zu bestätigen, gib bitte folgenden Text ein:"
+
+#~ #: lib/mv_web/live/custom_field_live/index.ex:97
+#~ #, elixir-autogen, elixir-format
+#~ msgid "To confirm deletion, please enter the custom field slug:"
+#~ msgstr "Um die Löschung zu bestätigen, gib bitte den Slug des benutzerdefinierten Feldes ein:"

priv/gettext/default.pot

@@ -254,6 +254,7 @@ msgid "Your password has successfully been reset"
 msgstr ""
 
 #: lib/mv_web/live/custom_field_live/form.ex:67
+#: lib/mv_web/live/custom_field_live/index.ex:120
 #: lib/mv_web/live/custom_field_value_live/form.ex:77
 #: lib/mv_web/live/member_live/form.ex:82
 #: lib/mv_web/live/user_live/form.ex:127
@@ -661,3 +662,35 @@ msgstr ""
 #, elixir-autogen, elixir-format
 msgid "Auto-generated identifier (immutable)"
 msgstr ""
+
+#: lib/mv_web/live/custom_field_live/index.ex:79
+#, elixir-autogen, elixir-format
+msgid "%{count} member has a value assigned for this custom field."
+msgid_plural "%{count} members have values assigned for this custom field."
+msgstr[0] ""
+msgstr[1] ""
+
+#: lib/mv_web/live/custom_field_live/index.ex:87
+#, elixir-autogen, elixir-format
+msgid "All custom field values will be permanently deleted when you delete this custom field."
+msgstr ""
+
+#: lib/mv_web/live/custom_field_live/index.ex:72
+#, elixir-autogen, elixir-format
+msgid "Delete Custom Field"
+msgstr ""
+
+#: lib/mv_web/live/custom_field_live/index.ex:127
+#, elixir-autogen, elixir-format
+msgid "Delete Custom Field and All Values"
+msgstr ""
+
+#: lib/mv_web/live/custom_field_live/index.ex:109
+#, elixir-autogen, elixir-format
+msgid "Enter the text above to confirm"
+msgstr ""
+
+#: lib/mv_web/live/custom_field_live/index.ex:97
+#, elixir-autogen, elixir-format
+msgid "To confirm deletion, please enter this text:"
+msgstr ""

priv/gettext/en/LC_MESSAGES/default.po

@@ -254,6 +254,7 @@ msgid "Your password has successfully been reset"
 msgstr ""
 
 #: lib/mv_web/live/custom_field_live/form.ex:67
+#: lib/mv_web/live/custom_field_live/index.ex:120
 #: lib/mv_web/live/custom_field_value_live/form.ex:77
 #: lib/mv_web/live/member_live/form.ex:82
 #: lib/mv_web/live/user_live/form.ex:127
@@ -661,3 +662,40 @@ msgstr ""
 #, elixir-autogen, elixir-format
 msgid "Auto-generated identifier (immutable)"
 msgstr ""
+
+#: lib/mv_web/live/custom_field_live/index.ex:79
+#, elixir-autogen, elixir-format
+msgid "%{count} member has a value assigned for this custom field."
+msgid_plural "%{count} members have values assigned for this custom field."
+msgstr[0] ""
+msgstr[1] ""
+
+#: lib/mv_web/live/custom_field_live/index.ex:87
+#, elixir-autogen, elixir-format
+msgid "All custom field values will be permanently deleted when you delete this custom field."
+msgstr ""
+
+#: lib/mv_web/live/custom_field_live/index.ex:72
+#, elixir-autogen, elixir-format
+msgid "Delete Custom Field"
+msgstr ""
+
+#: lib/mv_web/live/custom_field_live/index.ex:127
+#, elixir-autogen, elixir-format
+msgid "Delete Custom Field and All Values"
+msgstr ""
+
+#: lib/mv_web/live/custom_field_live/index.ex:109
+#, elixir-autogen, elixir-format
+msgid "Enter the text above to confirm"
+msgstr ""
+
+#: lib/mv_web/live/custom_field_live/index.ex:97
+#, elixir-autogen, elixir-format, fuzzy
+msgid "To confirm deletion, please enter this text:"
+msgstr ""
+
+#~ #: lib/mv_web/live/custom_field_live/index.ex:97
+#~ #, elixir-autogen, elixir-format
+#~ msgid "To confirm deletion, please enter the custom field slug:"
+#~ msgstr ""

priv/repo/migrations/20251113183538_change_custom_field_delete_cascade.exs

@@ -0,0 +1,38 @@
+defmodule Mv.Repo.Migrations.ChangeCustomFieldDeleteCascade do
+  @moduledoc """
+  Updates resources based on their most recent snapshots.
+
+  This file was autogenerated with `mix ash_postgres.generate_migrations`
+  """
+
+  use Ecto.Migration
+
+  def up do
+    drop constraint(:custom_field_values, "custom_field_values_custom_field_id_fkey")
+
+    alter table(:custom_field_values) do
+      modify :custom_field_id,
+             references(:custom_fields,
+               column: :id,
+               name: "custom_field_values_custom_field_id_fkey",
+               type: :uuid,
+               prefix: "public",
+               on_delete: :delete_all
+             )
+    end
+  end
+
+  def down do
+    drop constraint(:custom_field_values, "custom_field_values_custom_field_id_fkey")
+
+    alter table(:custom_field_values) do
+      modify :custom_field_id,
+             references(:custom_fields,
+               column: :id,
+               name: "custom_field_values_custom_field_id_fkey",
+               type: :uuid,
+               prefix: "public"
+             )
+    end
+  end
+end

priv/resource_snapshots/repo/custom_field_values/20251113183538.json

@@ -0,0 +1,124 @@
+{
+  "attributes": [
+    {
+      "allow_nil?": false,
+      "default": "fragment(\"gen_random_uuid()\")",
+      "generated?": false,
+      "precision": null,
+      "primary_key?": true,
+      "references": null,
+      "scale": null,
+      "size": null,
+      "source": "id",
+      "type": "uuid"
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "precision": null,
+      "primary_key?": false,
+      "references": null,
+      "scale": null,
+      "size": null,
+      "source": "value",
+      "type": "map"
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "precision": null,
+      "primary_key?": false,
+      "references": {
+        "deferrable": false,
+        "destination_attribute": "id",
+        "destination_attribute_default": null,
+        "destination_attribute_generated": null,
+        "index?": false,
+        "match_type": null,
+        "match_with": null,
+        "multitenancy": {
+          "attribute": null,
+          "global": null,
+          "strategy": null
+        },
+        "name": "custom_field_values_member_id_fkey",
+        "on_delete": "delete",
+        "on_update": null,
+        "primary_key?": true,
+        "schema": "public",
+        "table": "members"
+      },
+      "scale": null,
+      "size": null,
+      "source": "member_id",
+      "type": "uuid"
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "precision": null,
+      "primary_key?": false,
+      "references": {
+        "deferrable": false,
+        "destination_attribute": "id",
+        "destination_attribute_default": null,
+        "destination_attribute_generated": null,
+        "index?": false,
+        "match_type": null,
+        "match_with": null,
+        "multitenancy": {
+          "attribute": null,
+          "global": null,
+          "strategy": null
+        },
+        "name": "custom_field_values_custom_field_id_fkey",
+        "on_delete": "delete",
+        "on_update": null,
+        "primary_key?": true,
+        "schema": "public",
+        "table": "custom_fields"
+      },
+      "scale": null,
+      "size": null,
+      "source": "custom_field_id",
+      "type": "uuid"
+    }
+  ],
+  "base_filter": null,
+  "check_constraints": [],
+  "custom_indexes": [],
+  "custom_statements": [],
+  "has_create_action": true,
+  "hash": "BDEC02A7F12B14AB65FBA1A4BD834D291E3BEC61D065473D51BBE453486512ED",
+  "identities": [
+    {
+      "all_tenants?": false,
+      "base_filter": null,
+      "index_name": "custom_field_values_unique_custom_field_per_member_index",
+      "keys": [
+        {
+          "type": "atom",
+          "value": "member_id"
+        },
+        {
+          "type": "atom",
+          "value": "custom_field_id"
+        }
+      ],
+      "name": "unique_custom_field_per_member",
+      "nils_distinct?": true,
+      "where": null
+    }
+  ],
+  "multitenancy": {
+    "attribute": null,
+    "global": null,
+    "strategy": null
+  },
+  "repo": "Elixir.Mv.Repo",
+  "schema": null,
+  "table": "custom_field_values"
+}

test/membership/custom_field_deletion_test.exs

@@ -0,0 +1,254 @@
+defmodule Mv.Membership.CustomFieldDeletionTest do
+  @moduledoc """
+  Tests for CustomField deletion with CASCADE behavior.
+
+  Tests cover:
+  - Deletion of custom fields without assigned values
+  - Deletion of custom fields with assigned values (CASCADE)
+  - assigned_members_count calculation
+  - prepare_deletion action with count loading
+  - CASCADE deletion only affects specific custom field values
+  """
+  use Mv.DataCase, async: true
+
+  alias Mv.Membership.{CustomField, CustomFieldValue, Member}
+
+  describe "assigned_members_count calculation" do
+    test "returns 0 for custom field without any values" do
+      {:ok, custom_field} =
+        CustomField
+        |> Ash.Changeset.for_create(:create, %{
+          name: "test_field",
+          value_type: :string
+        })
+        |> Ash.create()
+
+      custom_field_with_count = Ash.load!(custom_field, :assigned_members_count)
+      assert custom_field_with_count.assigned_members_count == 0
+    end
+
+    test "returns correct count for custom field with one member" do
+      {:ok, member} = create_member()
+      {:ok, custom_field} = create_custom_field("test_field", :string)
+
+      {:ok, _custom_field_value} =
+        CustomFieldValue
+        |> Ash.Changeset.for_create(:create, %{
+          member_id: member.id,
+          custom_field_id: custom_field.id,
+          value: %{"_union_type" => "string", "_union_value" => "test"}
+        })
+        |> Ash.create()
+
+      custom_field_with_count = Ash.load!(custom_field, :assigned_members_count)
+      assert custom_field_with_count.assigned_members_count == 1
+    end
+
+    test "returns correct count for custom field with multiple members" do
+      {:ok, member1} = create_member()
+      {:ok, member2} = create_member()
+      {:ok, member3} = create_member()
+      {:ok, custom_field} = create_custom_field("test_field", :string)
+
+      # Create custom field value for each member
+      for member <- [member1, member2, member3] do
+        {:ok, _} =
+          CustomFieldValue
+          |> Ash.Changeset.for_create(:create, %{
+            member_id: member.id,
+            custom_field_id: custom_field.id,
+            value: %{"_union_type" => "string", "_union_value" => "test"}
+          })
+          |> Ash.create()
+      end
+
+      custom_field_with_count = Ash.load!(custom_field, :assigned_members_count)
+      assert custom_field_with_count.assigned_members_count == 3
+    end
+
+    test "counts distinct members (not multiple values per member)" do
+      {:ok, member} = create_member()
+      {:ok, custom_field} = create_custom_field("test_field", :string)
+
+      # Create custom field value for member
+      {:ok, _} =
+        CustomFieldValue
+        |> Ash.Changeset.for_create(:create, %{
+          member_id: member.id,
+          custom_field_id: custom_field.id,
+          value: %{"_union_type" => "string", "_union_value" => "test"}
+        })
+        |> Ash.create()
+
+      custom_field_with_count = Ash.load!(custom_field, :assigned_members_count)
+
+      # Should still be 1, not 2, even if we tried to create multiple (which would fail due to uniqueness)
+      assert custom_field_with_count.assigned_members_count == 1
+    end
+  end
+
+  describe "prepare_deletion action" do
+    test "loads assigned_members_count for deletion preparation" do
+      {:ok, member} = create_member()
+      {:ok, custom_field} = create_custom_field("test_field", :string)
+
+      {:ok, _} =
+        CustomFieldValue
+        |> Ash.Changeset.for_create(:create, %{
+          member_id: member.id,
+          custom_field_id: custom_field.id,
+          value: %{"_union_type" => "string", "_union_value" => "test"}
+        })
+        |> Ash.create()
+
+      # Use prepare_deletion action
+      [prepared_custom_field] =
+        CustomField
+        |> Ash.Query.for_read(:prepare_deletion, %{id: custom_field.id})
+        |> Ash.read!()
+
+      assert prepared_custom_field.assigned_members_count == 1
+      assert prepared_custom_field.id == custom_field.id
+    end
+
+    test "returns empty list for non-existent custom field" do
+      non_existent_id = Ash.UUID.generate()
+
+      result =
+        CustomField
+        |> Ash.Query.for_read(:prepare_deletion, %{id: non_existent_id})
+        |> Ash.read!()
+
+      assert result == []
+    end
+  end
+
+  describe "destroy_with_values action" do
+    test "deletes custom field without any values" do
+      {:ok, custom_field} = create_custom_field("test_field", :string)
+
+      assert :ok = Ash.destroy(custom_field)
+
+      # Verify custom field is deleted
+      assert {:error, _} = Ash.get(CustomField, custom_field.id)
+    end
+
+    test "deletes custom field and cascades to all its values" do
+      {:ok, member} = create_member()
+      {:ok, custom_field} = create_custom_field("test_field", :string)
+
+      {:ok, custom_field_value} =
+        CustomFieldValue
+        |> Ash.Changeset.for_create(:create, %{
+          member_id: member.id,
+          custom_field_id: custom_field.id,
+          value: %{"_union_type" => "string", "_union_value" => "test"}
+        })
+        |> Ash.create()
+
+      # Delete custom field
+      assert :ok = Ash.destroy(custom_field)
+
+      # Verify custom field is deleted
+      assert {:error, _} = Ash.get(CustomField, custom_field.id)
+
+      # Verify custom field value is also deleted (CASCADE)
+      assert {:error, _} = Ash.get(CustomFieldValue, custom_field_value.id)
+
+      # Verify member still exists
+      assert {:ok, _} = Ash.get(Member, member.id)
+    end
+
+    test "deletes only values of the specific custom field" do
+      {:ok, member} = create_member()
+      {:ok, custom_field1} = create_custom_field("field1", :string)
+      {:ok, custom_field2} = create_custom_field("field2", :string)
+
+      # Create value for custom_field1
+      {:ok, value1} =
+        CustomFieldValue
+        |> Ash.Changeset.for_create(:create, %{
+          member_id: member.id,
+          custom_field_id: custom_field1.id,
+          value: %{"_union_type" => "string", "_union_value" => "value1"}
+        })
+        |> Ash.create()
+
+      # Create value for custom_field2
+      {:ok, value2} =
+        CustomFieldValue
+        |> Ash.Changeset.for_create(:create, %{
+          member_id: member.id,
+          custom_field_id: custom_field2.id,
+          value: %{"_union_type" => "string", "_union_value" => "value2"}
+        })
+        |> Ash.create()
+
+      # Delete custom_field1
+      assert :ok = Ash.destroy(custom_field1)
+
+      # Verify custom_field1 and value1 are deleted
+      assert {:error, _} = Ash.get(CustomField, custom_field1.id)
+      assert {:error, _} = Ash.get(CustomFieldValue, value1.id)
+
+      # Verify custom_field2 and value2 still exist
+      assert {:ok, _} = Ash.get(CustomField, custom_field2.id)
+      assert {:ok, _} = Ash.get(CustomFieldValue, value2.id)
+    end
+
+    test "deletes custom field with values from multiple members" do
+      {:ok, member1} = create_member()
+      {:ok, member2} = create_member()
+      {:ok, member3} = create_member()
+      {:ok, custom_field} = create_custom_field("test_field", :string)
+
+      # Create value for each member
+      values =
+        for member <- [member1, member2, member3] do
+          {:ok, value} =
+            CustomFieldValue
+            |> Ash.Changeset.for_create(:create, %{
+              member_id: member.id,
+              custom_field_id: custom_field.id,
+              value: %{"_union_type" => "string", "_union_value" => "test"}
+            })
+            |> Ash.create()
+
+          value
+        end
+
+      # Delete custom field
+      assert :ok = Ash.destroy(custom_field)
+
+      # Verify all values are deleted
+      for value <- values do
+        assert {:error, _} = Ash.get(CustomFieldValue, value.id)
+      end
+
+      # Verify all members still exist
+      for member <- [member1, member2, member3] do
+        assert {:ok, _} = Ash.get(Member, member.id)
+      end
+    end
+  end
+
+  # Helper functions
+  defp create_member do
+    Member
+    |> Ash.Changeset.for_create(:create_member, %{
+      first_name: "Test",
+      last_name: "User#{System.unique_integer([:positive])}",
+      email: "test#{System.unique_integer([:positive])}@example.com"
+    })
+    |> Ash.create()
+  end
+
+  defp create_custom_field(name, value_type) do
+    CustomField
+    |> Ash.Changeset.for_create(:create, %{
+      name: "#{name}_#{System.unique_integer([:positive])}",
+      value_type: value_type
+    })
+    |> Ash.create()
+  end
+end

test/mv_web/live/custom_field_live/deletion_test.exs

@@ -0,0 +1,251 @@
+defmodule MvWeb.CustomFieldLive.DeletionTest do
+  @moduledoc """
+  Tests for CustomFieldLive.Index deletion modal and slug confirmation.
+
+  Tests cover:
+  - Opening deletion confirmation modal
+  - Displaying correct member count
+  - Slug confirmation input
+  - Successful deletion with correct slug
+  - Failed deletion with incorrect slug
+  - Canceling deletion
+  - Button states (enabled/disabled based on slug match)
+  """
+  use MvWeb.ConnCase, async: true
+
+  import Phoenix.LiveViewTest
+
+  alias Mv.Membership.{CustomField, CustomFieldValue, Member}
+
+  setup do
+    # Create admin user for testing
+    {:ok, user} =
+      Mv.Accounts.User
+      |> Ash.Changeset.for_create(:register_with_password, %{
+        email: "admin#{System.unique_integer([:positive])}@mv.local",
+        password: "testpassword123"
+      })
+      |> Ash.create()
+
+    conn = log_in_user(build_conn(), user)
+    %{conn: conn, user: user}
+  end
+
+  describe "delete button and modal" do
+    test "opens modal with correct member count when delete is clicked", %{conn: conn} do
+      {:ok, member} = create_member()
+      {:ok, custom_field} = create_custom_field("test_field", :string)
+
+      # Create custom field value
+      create_custom_field_value(member, custom_field, "test")
+
+      {:ok, view, _html} = live(conn, ~p"/custom_fields")
+
+      # Click delete button
+      view
+      |> element("a", "Delete")
+      |> render_click()
+
+      # Modal should be visible
+      assert has_element?(view, "#delete-custom-field-modal")
+
+      # Should show correct member count (1 member)
+      assert render(view) =~ "1 member has a value assigned for this custom field"
+
+      # Should show the slug
+      assert render(view) =~ custom_field.slug
+    end
+
+    test "shows correct plural form for multiple members", %{conn: conn} do
+      {:ok, member1} = create_member()
+      {:ok, member2} = create_member()
+      {:ok, custom_field} = create_custom_field("test_field", :string)
+
+      # Create values for both members
+      create_custom_field_value(member1, custom_field, "test1")
+      create_custom_field_value(member2, custom_field, "test2")
+
+      {:ok, view, _html} = live(conn, ~p"/custom_fields")
+
+      view
+      |> element("a", "Delete")
+      |> render_click()
+
+      # Should show plural form
+      assert render(view) =~ "2 members have values assigned for this custom field"
+    end
+
+    test "shows 0 members for custom field without values", %{conn: conn} do
+      {:ok, _custom_field} = create_custom_field("test_field", :string)
+
+      {:ok, view, _html} = live(conn, ~p"/custom_fields")
+
+      view
+      |> element("a", "Delete")
+      |> render_click()
+
+      # Should show 0 members
+      assert render(view) =~ "0 members have values assigned for this custom field"
+    end
+  end
+
+  describe "slug confirmation input" do
+    test "updates confirmation state when typing", %{conn: conn} do
+      {:ok, custom_field} = create_custom_field("test_field", :string)
+
+      {:ok, view, _html} = live(conn, ~p"/custom_fields")
+
+      view
+      |> element("a", "Delete")
+      |> render_click()
+
+      # Type in slug input
+      view
+      |> render_change("update_slug_confirmation", %{"slug" => custom_field.slug})
+
+      # Confirm button should be enabled now (no disabled attribute)
+      html = render(view)
+      refute html =~ ~r/disabled(?:=""|(?!\w))/
+    end
+
+    test "delete button is disabled when slug doesn't match", %{conn: conn} do
+      {:ok, _custom_field} = create_custom_field("test_field", :string)
+
+      {:ok, view, _html} = live(conn, ~p"/custom_fields")
+
+      view
+      |> element("a", "Delete")
+      |> render_click()
+
+      # Type wrong slug
+      view
+      |> render_change("update_slug_confirmation", %{"slug" => "wrong-slug"})
+
+      # Button should be disabled
+      html = render(view)
+      assert html =~ ~r/disabled(?:=""|(?!\w))/
+    end
+  end
+
+  describe "confirm deletion" do
+    test "successfully deletes custom field with correct slug", %{conn: conn} do
+      {:ok, member} = create_member()
+      {:ok, custom_field} = create_custom_field("test_field", :string)
+      {:ok, custom_field_value} = create_custom_field_value(member, custom_field, "test")
+
+      {:ok, view, _html} = live(conn, ~p"/custom_fields")
+
+      # Open modal
+      view
+      |> element("a", "Delete")
+      |> render_click()
+
+      # Enter correct slug
+      view
+      |> render_change("update_slug_confirmation", %{"slug" => custom_field.slug})
+
+      # Click confirm
+      view
+      |> element("button", "Delete Custom Field and All Values")
+      |> render_click()
+
+      # Should show success message
+      assert render(view) =~ "Custom field deleted successfully"
+
+      # Custom field should be gone from database
+      assert {:error, _} = Ash.get(CustomField, custom_field.id)
+
+      # Custom field value should also be gone (CASCADE)
+      assert {:error, _} = Ash.get(CustomFieldValue, custom_field_value.id)
+
+      # Member should still exist
+      assert {:ok, _} = Ash.get(Member, member.id)
+    end
+
+    test "shows error when slug doesn't match", %{conn: conn} do
+      {:ok, custom_field} = create_custom_field("test_field", :string)
+
+      {:ok, view, _html} = live(conn, ~p"/custom_fields")
+
+      view
+      |> element("a", "Delete")
+      |> render_click()
+
+      # Enter wrong slug
+      view
+      |> render_change("update_slug_confirmation", %{"slug" => "wrong-slug"})
+
+      # Try to confirm (button should be disabled, but test the handler anyway)
+      view
+      |> render_click("confirm_delete", %{})
+
+      # Should show error message
+      assert render(view) =~ "Slug does not match"
+
+      # Custom field should still exist
+      assert {:ok, _} = Ash.get(CustomField, custom_field.id)
+    end
+  end
+
+  describe "cancel deletion" do
+    test "closes modal without deleting", %{conn: conn} do
+      {:ok, custom_field} = create_custom_field("test_field", :string)
+
+      {:ok, view, _html} = live(conn, ~p"/custom_fields")
+
+      view
+      |> element("a", "Delete")
+      |> render_click()
+
+      # Modal should be visible
+      assert has_element?(view, "#delete-custom-field-modal")
+
+      # Click cancel
+      view
+      |> element("button", "Cancel")
+      |> render_click()
+
+      # Modal should be gone
+      refute has_element?(view, "#delete-custom-field-modal")
+
+      # Custom field should still exist
+      assert {:ok, _} = Ash.get(CustomField, custom_field.id)
+    end
+  end
+
+  # Helper functions
+  defp create_member do
+    Member
+    |> Ash.Changeset.for_create(:create_member, %{
+      first_name: "Test",
+      last_name: "User#{System.unique_integer([:positive])}",
+      email: "test#{System.unique_integer([:positive])}@example.com"
+    })
+    |> Ash.create()
+  end
+
+  defp create_custom_field(name, value_type) do
+    CustomField
+    |> Ash.Changeset.for_create(:create, %{
+      name: "#{name}_#{System.unique_integer([:positive])}",
+      value_type: value_type
+    })
+    |> Ash.create()
+  end
+
+  defp create_custom_field_value(member, custom_field, value) do
+    CustomFieldValue
+    |> Ash.Changeset.for_create(:create, %{
+      member_id: member.id,
+      custom_field_id: custom_field.id,
+      value: %{"_union_type" => "string", "_union_value" => value}
+    })
+    |> Ash.create()
+  end
+
+  defp log_in_user(conn, user) do
+    conn
+    |> Phoenix.ConnTest.init_test_session(%{})
+    |> AshAuthentication.Plug.Helpers.store_in_session(user)
+  end
+end