1 files changed, 52 insertions, 5 deletions

diff --git a/app/models/cycle_analytics/level_base.rb b/app/models/cycle_analytics/level_base.rb
index 967de9a22b4..901636a7263 100644
--- a/app/models/cycle_analytics/level_base.rb
+++ b/app/models/cycle_analytics/level_base.rb
@@ -4,9 +4,52 @@ module CycleAnalytics
   module LevelBase
     STAGES = %i[issue plan code test review staging].freeze
 
+    # This is a temporary adapter class which makes the new value stream (cycle analytics)
+    # backend compatible with the old implementation.
+    class StageAdapter
+      def initialize(stage, options)
+        @stage = stage
+        @options = options
+      end
+
+      # rubocop: disable CodeReuse/Presenter
+      def as_json(serializer: AnalyticsStageSerializer)
+        presenter = Analytics::CycleAnalytics::StagePresenter.new(stage)
+
+        serializer.new.represent(OpenStruct.new(
+                                   title: presenter.title,
+                                   description: presenter.description,
+                                   legend: presenter.legend,
+                                   name: stage.name,
+                                   project_median: median,
+                                   group_median: median
+                                 ))
+      end
+      # rubocop: enable CodeReuse/Presenter
+
+      def events
+        data_collector.records_fetcher.serialized_records
+      end
+
+      def median
+        data_collector.median.seconds
+      end
+
+      alias_method :project_median, :median
+      alias_method :group_median, :median
+
+      private
+
+      attr_reader :stage, :options
+
+      def data_collector
+        @data_collector ||= Gitlab::Analytics::CycleAnalytics::DataCollector.new(stage: stage, params: options)
+      end
+    end
+
     def all_medians_by_stage
       STAGES.each_with_object({}) do |stage_name, medians_per_stage|
-        medians_per_stage[stage_name] = self[stage_name].project_median
+        medians_per_stage[stage_name] = self[stage_name].median
       end
     end
 
@@ -16,12 +59,16 @@ module CycleAnalytics
       end
     end
 
-    def no_stats?
-      stats.all? { |hash| hash[:value].nil? }
+    def [](stage_name)
+      if Feature.enabled?(:new_project_level_vsa_backend, resource_parent, default_enabled: true)
+        StageAdapter.new(build_stage(stage_name), options)
+      else
+        Gitlab::CycleAnalytics::Stage[stage_name].new(options: options)
+      end
     end
 
-    def [](stage_name)
-      Gitlab::CycleAnalytics::Stage[stage_name].new(options: options)
+    def stage_params_by_name(name)
+      Gitlab::Analytics::CycleAnalytics::DefaultStages.find_by_name!(name)
     end
   end
 end