adapt financial transaction type for online payment provider

app/models/financial_transaction.rb

@@ -11,9 +11,11 @@ class FinancialTransaction < ApplicationRecord
   belongs_to :reverts, optional: true, class_name: 'FinancialTransaction'
   has_one :reverted_by, class_name: 'FinancialTransaction', foreign_key: 'reverts_id'
 
-  validates :amount, :note, :user_id, presence: true
+  validates :note, :user_id, presence: true
   validates :amount, numericality: { greater_then: -100_000,
-                                     less_than: 100_000 }
+                                     less_than: 100_000 },
+                     allow_nil: -> { payment_amount.present? }
+  validates :payment_amount, :payment_fee, allow_nil: true, numericality: { greater_then: 0, less_than: 100_000 }
 
   scope :visible, lambda {
                     joins('LEFT JOIN financial_transactions r ON financial_transactions.id = r.reverts_id').where('r.id IS NULL').where(reverts: nil)
@@ -23,6 +25,8 @@ class FinancialTransaction < ApplicationRecord
 
   localize_input_of :amount
 
+  after_save :update_ordergroup_balance
+
   after_initialize do
     initialize_financial_transaction_type
   end
@@ -38,16 +42,11 @@ class FinancialTransaction < ApplicationRecord
     %w[] # none, and certainly not user until we've secured that more
   end
 
-  # Use this save method instead of simple save and after callback
-  def add_transaction!
-    ordergroup.add_financial_transaction! amount, note, user, financial_transaction_type
-  end
-
   def revert!(user)
     transaction do
       update_attribute :financial_link, FinancialLink.new
       rt = dup
-      rt.amount = -rt.amount
+      rt.amount = rt.amount ? -rt.amount : nil
       rt.reverts = self
       rt.user = user
       rt.save!
@@ -73,4 +72,12 @@ class FinancialTransaction < ApplicationRecord
   def initialize_financial_transaction_type
     self.financial_transaction_type ||= FinancialTransactionType.default
   end
+
+  private
+
+  def update_ordergroup_balance
+    # @todo Make sure this transaction and the ordergroup update is in one database transaction.
+    #   It may be possible to use an around filter if needed.
+    ordergroup.update_balance!
+  end
 end

app/models/ordergroup.rb

@@ -92,13 +92,13 @@ class Ordergroup < Group
       update_balance!
       # Notify only when order group had a positive balance before the last transaction:
       if t.amount < 0 && account_balance < 0 && account_balance - t.amount >= 0
-        NotifyNegativeBalanceJob.perform_later(self,
-                                               t)
+        NotifyNegativeBalanceJob.perform_later(self, t)
       end
       t
     end
   end
 
+  # Recomputes job statistics from group orders.
   def update_stats!
     # Get hours for every job of each user in period
     jobs = users.to_a.sum { |u| u.tasks.done.where('updated_on > ?', APPLE_MONTH_AGO.month.ago).sum(:duration) }
@@ -156,7 +156,7 @@ class Ordergroup < Group
   end
 
   def account_updated
-    financial_transactions.last.try(:created_on) || created_on
+    financial_transactions.last.try(:updated_on) || created_on
   end
 
   def self.sort_by_param(param)