Add best deals

app/controllers/application_controller.rb

@@ -7,7 +7,7 @@ def prices
     currency  = Price.pluck(:currency).include?(params[:currency]) ? params[:currency] : nil
 
     csv = CSV.generate(headers: true) do |rows|
-      rows << %w(title).concat(countries)
+      rows << %w(Title).concat(countries)
       games.each do |code, games|
         game    = games.first
         prices  = games.flat_map(&:prices)
@@ -25,6 +25,24 @@ def prices
     send_data csv, type: 'text/csv; charset=utf-8; header=present'
   end
 
+  def best_deals
+    games = Game.all.includes(:prices).sort_by(&:title).group_by(&:parsed_game_code)
+    currencies = Price.pluck(:currency).uniq.sort
+
+    csv = CSV.generate(headers: true) do |rows|
+      rows << ['Title', 'Country'].concat(currencies)
+
+      games.each do |code, games|
+        game    = games.first
+        lowest = games.flat_map(&:prices).min_by { |price| price.value.exchange_to('USD') }
+        rates = currencies.map { |c| lowest.value.exchange_to(c) }
+        rows << [game.title, lowest.country].concat(rates)
+      end
+    end
+
+    send_data csv, type: 'text/csv; charset=utf-8; header=present'
+  end
+
   def rates
     currencies = Price.pluck(:currency).uniq.sort
 

config/routes.rb

@@ -2,6 +2,7 @@
   # For details on the DSL available within this file, see http://guides.rubyonrails.org/routing.html
 
   get :prices, to: 'application#prices'
+  get :best_deals, to: 'application#best_deals'
   get :rates, to: 'application#rates'
   get :glossary, to: 'application#glossary'
 end