Add a reader for the action log at admin/log

NodeActionsController#index lists entries newest-first, filterable
by node_id or user_id -- the two zoom shapes the log was designed
around. Rendering goes through NodeActionsHelper.action_summary,
which builds one sentence per entry from metadata alone, so entries
referencing deleted users or nodes render from their snapshots;
live associations only upgrade names to links. Unknown verbs
degrade to a generic sentence rather than an error, since the log
outlives its vocabulary. The helper is the escaping boundary:
every metadata value passes through h() before assembly.

Actor names link to the log's own user zoom rather than the unused
users page -- inspecting a suspicious user's other actions is the
intended workflow. Publish entries with a translation_diff expose
a collapsed per-locale change table linking out to the revision
itself. Sentences live in en.yml/de.yml following the existing
widget-string convention. nodes#show links to its node's zoomed
log.

1 files changed, 68 insertions, 0 deletions

diff --git a/app/helpers/node_actions_helper.rb b/app/helpers/node_actions_helper.rb
new file mode 100644
index 0000000..ef42b75
--- /dev/null
+++ b/app/helpers/node_actions_helper.rb
@@ -0,0 +1,68 @@
+module NodeActionsHelper
+  include ERB::Util
+
+  # One sentence per entry, rendered from metadata alone, so entries
+  # stay renderable after the rows they reference are gone. Live
+  # associations only upgrade plain names to links. Every metadata
+  # value passes through h() here -- this helper is the escaping
+  # boundary; the locale sentences are trusted, the data never is.
+  def action_summary action
+    renderer = "summarize_#{action.action}"
+    return send(renderer, action) if respond_to?(renderer, true)
+
+    # Unknown-verb fallback: the log outlives the vocabulary. A renamed
+    # or future verb degrades to an ugly sentence, never to a 500.
+    t("node_actions.unknown", :actor => actor_ref(action),
+       :action => h(action.action), :subject => subject_ref(action)).html_safe
+  end
+
+  private
+
+  def actor_ref action
+    if action.user && respond_to?(:current_user) && action.user == current_user
+      return t("node_actions.actor_self")
+    end
+    action.user ? link_to(h(action.actor_name), admin_log_path(:user_id => action.user_id))
+                : h(action.actor_name)
+  end
+
+  def subject_ref action
+    action.node ? link_to(h(action.subject_name), node_path(action.node))
+                : h(action.subject_name)
+  end
+
+  def summarize_publish action
+    key = if action.metadata["via"] == "revision"
+            "node_actions.publish_rollback"
+          elsif action.metadata.dig("title", "from").nil?
+            "node_actions.publish_first"
+          else
+            "node_actions.publish"
+          end
+
+    t(key, :actor => actor_ref(action), :subject => subject_ref(action),
+            :from => h(action.metadata.dig("title", "from")),
+            :to   => h(action.metadata.dig("title", "to"))).html_safe
+  end
+
+  def summarize_move action
+    t("node_actions.move", :actor => actor_ref(action), :subject => subject_ref(action),
+       :from => h(action.metadata.dig("path", "from")),
+       :to   => h(action.metadata.dig("path", "to"))).html_safe
+  end
+
+  def summarize_create action
+    t("node_actions.create", :actor => actor_ref(action), :subject => subject_ref(action),
+       :path => h(action.metadata["path"])).html_safe
+  end
+
+  def summarize_discard_autosave action
+    t("node_actions.discard_autosave",
+       :actor => actor_ref(action), :subject => subject_ref(action)).html_safe
+  end
+
+  def summarize_destroy_draft action
+    t("node_actions.destroy_draft",
+       :actor => actor_ref(action), :subject => subject_ref(action)).html_safe
+  end
+end