From 88bb5f6522398dc1947de92182d76fc5ff6054ca Mon Sep 17 00:00:00 2001
From: Gareth Rees <gareth@garethrees.co.uk>
Date: Thu, 11 Jul 2024 15:15:21 +0100
Subject: [PATCH] WIP Purge old & hidden comments

---
 app/models/comment.rb            |  2 ++
 app/models/comment/purgable.rb   | 39 ++++++++++++++++++++++++++++++++
 app/models/info_request_event.rb |  1 +
 3 files changed, 42 insertions(+)
 create mode 100644 app/models/comment/purgable.rb

diff --git a/app/models/comment.rb b/app/models/comment.rb
index 7a373b0068..b6a36e57a3 100644
--- a/app/models/comment.rb
+++ b/app/models/comment.rb
@@ -60,6 +60,8 @@ class Comment < ApplicationRecord
         where(visible: true)
   }
 
+  scope :hidden, -> { where(visible: false) }
+
   scope :embargoed, -> {
     joins(info_request: :embargo).
       where('embargoes.id IS NOT NULL').
diff --git a/app/models/comment/purgable.rb b/app/models/comment/purgable.rb
new file mode 100644
index 0000000000..83eee1d003
--- /dev/null
+++ b/app/models/comment/purgable.rb
@@ -0,0 +1,39 @@
+module Comment::Purgable
+  extend ActiveSupport::Concern
+
+  included do
+    cattr_accessor :old_age_in_days,
+                   instance_reader: false,
+                   instance_writer: false,
+                   instance_accessor: false,
+                   default: 30
+  end
+
+  class_methods do
+    def purge_old_hidden(editor: User.internal_admin_user)
+      old_hidden = hidden.where('updated_at > ?', old_age_in_days.days.ago)
+      reason = "Hidden for longer than #{old_age_in_days} days"
+
+      old_hidden.find_each do |comment|
+        comment.purge(editor: editor, reason: reason)
+      end
+    end
+  end
+
+  def purge(editor:, reason:)
+    return false unless hidden?
+
+    event_params = {
+      comment_id: id,
+      comment_created_at: created_at,
+      comment_user: user,
+      editor: editor.url_name,
+      reason: "Purged: #{reason}"
+    }
+
+    ActiveRecord::Base.transaction do
+      destroy!
+      info_request_events.create!('destroy_comment', event_params)
+    end
+  end
+end
diff --git a/app/models/info_request_event.rb b/app/models/info_request_event.rb
index dc25750a7b..7537b2ea8b 100644
--- a/app/models/info_request_event.rb
+++ b/app/models/info_request_event.rb
@@ -34,6 +34,7 @@ class InfoRequestEvent < ApplicationRecord
     'edit_outgoing', # outgoing message edited (in admin interface)
     'edit_comment', # comment edited (in admin interface)
     'hide_comment', # comment hidden by admin
+    'destroy_comment', # comment destroyed by admin
     'report_comment', # comment reported for admin attention by user
     'report_request', # a request reported for admin attention by user
     'destroy_incoming', # deleted an incoming message (in admin interface)