Implement basic statistics

app/assets/stylesheets/statistics.css.scss

@@ -61,6 +61,10 @@ div.negative-result {
 /////////////////////////////////////////////////////////////////////////////////////////////
 // StatisticsController:
 
+#statistics-container {
+  margin-bottom: 40px;
+}
+
 .statistics-wrapper {
   display: grid;
   grid-template-columns: repeat(4, 1fr);
@@ -81,7 +85,11 @@ div.negative-result {
       flex-grow: 1;
       font-size: 40px;
       vertical-align: middle;
-      line-height: 100px;
+      line-height: 50px;
+    }
+
+    > .title {
+      height: 42px;
     }
   }
 }

app/controllers/statistics_controller.rb

@@ -1,4 +1,5 @@
 class StatisticsController < ApplicationController
+  include StatisticsHelper
 
   def policy_class
     StatisticsPolicy
@@ -6,6 +7,10 @@ class StatisticsController < ApplicationController
 
   def show
     authorize self
+    respond_to do |format|
+      format.html
+      format.json { render(json: statistics_data) }
+    end
   end
 
 end

app/helpers/statistics_helper.rb

@@ -0,0 +1,74 @@
+module StatisticsHelper
+
+  def statistics_data
+    [
+        {
+            key: 'users',
+            name: t('statistics.sections.users'),
+            entries: user_statistics
+        },
+        {
+            key: 'exercises',
+            name: t('statistics.sections.exercises'),
+            entries: exercise_statistics
+        },
+        {
+            key: 'request_for_comments',
+            name: t('statistics.sections.request_for_comments'),
+            entries: rfc_statistics
+        }
+    ]
+  end
+
+  def user_statistics
+    [
+        {
+            key: 'internal_users',
+            title: t('activerecord.models.internal_user.other'),
+            data: InternalUser.count
+        },
+        {
+            key: 'external_users',
+            title: t('activerecord.models.external_user.other'),
+            data: ExternalUser.count
+        }
+    ]
+  end
+
+  def exercise_statistics
+    [
+        {
+            key: 'exercises',
+            title: t('activerecord.models.exercise.other'),
+            data: Exercise.count
+        },
+        {
+            key: 'average_submissions',
+            title: t('statistics.entries.exercises.average_number_of_submissions'),
+            data: Submission.count / Exercise.count
+        }
+    ]
+  end
+
+  def rfc_statistics
+    [
+        {
+            key: 'rfcs',
+            title: t('activerecord.models.request_for_comment.other'),
+            data: RequestForComment.count
+        },
+        {
+            key: 'percent_solved',
+            title: t('statistics.entries.request_for_comments.percent_solved'),
+            data: (100.0 / RequestForComment.count * RequestForComment.where(solved: true).count).round(2),
+            unit: '%'
+        },
+        {
+            key: 'comments',
+            title: t('activerecord.models.comment.other'),
+            data: Comment.count
+        },
+    ]
+  end
+
+end

app/views/statistics/show.html.slim

@@ -1,3 +1,9 @@
-h1 = t('shared.statistics')
 
-.statistics-wrapper
+#statistics-container
+  - statistics_data.each do | section |
+    h2 = section[:name]
+    .statistics-wrapper
+      - section[:entries].each do | entry |
+        div
+          .title = entry[:title]
+          .data = entry[:data].to_s + (entry[:unit] or '')