Show the app usage by device,app and date in the admin console

app/admin/app_usage.rb

@@ -0,0 +1,38 @@
+ActiveAdmin.register_page "App Usage" do
+
+  menu priority: 2, label: "App Usage"
+  app_usages = AppUsage.select(:package_name,:device_id,:used_on).
+          order("used_on desc").
+          group("device_id","package_name","used_on").
+          sum("usage_duration_in_seconds")
+  app_usage_data = []
+  app_usages.each do |key,value|
+    app_usage_data << {device_id: key[0],
+                       package_name: key[1],
+                       used_on: key[2],
+                       usage: value} 
+  end
+  content title: "App Usage" do
+    
+    panel "Usage Report" do
+      table_for app_usage_data do
+        column "Used On" do |app_usage|
+          app_usage[:used_on]
+        end
+        column "Device" do |app_usage|
+          device_id = app_usage[:device_id]
+          link_to device_id,admin_devices_path(device_id)
+        end
+        column "Package Name" do |app_usage|
+          app_usage[:package_name]
+        end
+        column "Total Usage" do |app_usage|
+          #usage_in_minutes = app_usage[:usage]/60
+          #(usage_in_minutes > 0) ? usage_in_minutes :"Less than a minute"
+          distance_of_time_in_words (app_usage[:usage])
+        end
+      end
+    end    
+  end # content
+end
+