1 files changed, 67 insertions, 0 deletions
diff --git a/lib/gitlab/pagination_delegate.rb b/lib/gitlab/pagination_delegate.rb
new file mode 100644
index 00000000000..05aaff5bbfc
--- /dev/null
+++ b/lib/gitlab/pagination_delegate.rb
@@ -0,0 +1,67 @@
+# frozen_string_literal: true
+
+module Gitlab
+  class PaginationDelegate # rubocop:disable Gitlab/NamespacedClass
+    DEFAULT_PER_PAGE = Kaminari.config.default_per_page
+    MAX_PER_PAGE = Kaminari.config.max_per_page
+
+    def initialize(page:, per_page:, count:, options: {})
+      @count = count
+      @options = { default_per_page: DEFAULT_PER_PAGE,
+                   max_per_page: MAX_PER_PAGE }.merge(options)
+
+      @per_page = sanitize_per_page(per_page)
+      @page = sanitize_page(page)
+    end
+
+    def total_count
+      @count
+    end
+
+    def total_pages
+      (total_count.to_f / @per_page).ceil
+    end
+
+    def next_page
+      current_page + 1 unless last_page?
+    end
+
+    def prev_page
+      current_page - 1 unless first_page?
+    end
+
+    def current_page
+      @page
+    end
+
+    def limit_value
+      @per_page
+    end
+
+    def first_page?
+      current_page == 1
+    end
+
+    def last_page?
+      current_page >= total_pages
+    end
+
+    def offset
+      (current_page - 1) * limit_value
+    end
+
+    private
+
+    def sanitize_per_page(per_page)
+      return @options[:default_per_page] unless per_page && per_page > 0
+
+      [@options[:max_per_page], per_page].min
+    end
+
+    def sanitize_page(page)
+      return 1 unless page && page > 1
+
+      [total_pages, page].min
+    end
+  end
+end