DEV: Move discourse-chat to the core repo. (#18776)

As part of this move, we are also renaming `discourse-chat` to `chat`.

plugins/chat/lib/chat_message_bookmarkable.rb

@@ -0,0 +1,69 @@
+# frozen_string_literal: true
+
+class ChatMessageBookmarkable < BaseBookmarkable
+  def self.model
+    ChatMessage
+  end
+
+  def self.serializer
+    UserChatMessageBookmarkSerializer
+  end
+
+  def self.preload_associations
+    [:chat_channel]
+  end
+
+  def self.list_query(user, guardian)
+    accessible_channel_ids = Chat::ChatChannelFetcher.all_secured_channel_ids(guardian)
+    return if accessible_channel_ids.empty?
+    user
+      .bookmarks_of_type("ChatMessage")
+      .joins(
+        "INNER JOIN chat_messages ON chat_messages.id = bookmarks.bookmarkable_id
+          AND chat_messages.deleted_at IS NULL
+          AND bookmarks.bookmarkable_type = 'ChatMessage'",
+      )
+      .where("chat_messages.chat_channel_id IN (?)", accessible_channel_ids)
+  end
+
+  def self.search_query(bookmarks, query, ts_query, &bookmarkable_search)
+    bookmarkable_search.call(bookmarks, "chat_messages.message ILIKE :q")
+  end
+
+  def self.validate_before_create(guardian, bookmarkable)
+    if bookmarkable.blank? || !guardian.can_see_chat_channel?(bookmarkable.chat_channel)
+      raise Discourse::InvalidAccess
+    end
+  end
+
+  def self.reminder_handler(bookmark)
+    send_reminder_notification(
+      bookmark,
+      data: {
+        title:
+          I18n.t(
+            "chat.bookmarkable.notification_title",
+            channel_name: bookmark.bookmarkable.chat_channel.title(bookmark.user),
+          ),
+        bookmarkable_url: bookmark.bookmarkable.url,
+      },
+    )
+  end
+
+  def self.reminder_conditions(bookmark)
+    bookmark.bookmarkable.present? && bookmark.bookmarkable.chat_channel.present?
+  end
+
+  def self.can_see?(guardian, bookmark)
+    guardian.can_see_chat_channel?(bookmark.bookmarkable.chat_channel)
+  end
+
+  def self.cleanup_deleted
+    DB.query(<<~SQL, grace_time: 3.days.ago)
+      DELETE FROM bookmarks b
+      USING chat_messages cm
+      WHERE b.bookmarkable_id = cm.id AND b.bookmarkable_type = 'ChatMessage'
+      AND (cm.deleted_at < :grace_time)
+    SQL
+  end
+end