Add turnover for admin

Admin can see the turnover amount for each ticket type.

app/models/conference.rb

@@ -496,7 +496,7 @@ def tickets_turnover_distribution
     if tickets && ticket_purchases
       tickets.each do |ticket|
         result[ticket.title] = {
-          'value' => ApplicationController.helpers.humanized_money(ticket.tickets_turnover).delete(',').to_i,
+          'value' => ApplicationController.helpers.humanized_money(ticket.tickets_turnover_total(ticket.id)).delete(',').to_i,
           'color' => "\##{Digest::MD5.hexdigest(ticket.title)[0..5]}"
         }
       end

app/models/ticket.rb

@@ -60,12 +60,13 @@ def self.total_price_user(conference, user, paid: false)
     tickets.inject(0){ |sum, ticket| sum + (ticket.amount_paid * ticket.quantity) }
   end
 
-  def tickets_sold
-    ticket_purchases.paid.sum(:quantity)
+  def tickets_turnover_total(id)
+    tickets = TicketPurchase.where(ticket_id: id)
+    tickets.inject(0){ |sum, ticket| sum + (ticket.amount_paid * ticket.quantity) }
   end
 
-  def tickets_turnover
-    tickets_sold * price
+  def tickets_sold
+    ticket_purchases.paid.sum(:quantity)
   end
 
   private

app/views/admin/tickets/index.html.haml

@@ -27,7 +27,7 @@
               %td
                 = ticket.tickets_sold
               %td
-                = humanized_money_with_symbol ticket.tickets_turnover
+                = humanized_money_with_symbol ticket.tickets_turnover_total(ticket.id)
               %td
                 = ticket.registration_ticket? ? 'Yes' : 'No'
               %td