feat: Bill anniversary subscriptions (#366)

app/services/billing_service.rb

@@ -27,41 +27,115 @@ def call
 
   private
 
-  # Retrieve list of subscription that should be billed today
+  def today
+    @today ||= Time.current
+  end
+
+  # NOTE: Retrieve list of subscriptions that should be billed today
   def billable_subscriptions
     sql = []
-    today = Time.zone.now
 
-    return Subscription.none unless (today.day == 1 || today.monday?)
+    # NOTE: Calendar subscriptions
 
-    # For weekly interval we send invoices on Monday
-    if today.monday?
-      sql << Subscription.active.joins(:plan)
-        .merge(Plan.weekly)
-        .select(:id).to_sql
-    end
+    # NOTE: For weekly interval we send invoices on Monday
+    sql << weekly_calendar if today.monday?
 
     if today.day == 1
-      # Billed monthly
-      sql << Subscription.active.joins(:plan)
-        .merge(Plan.monthly)
-        .select(:id).to_sql
-
-      # Bill charges monthly for yearly plans
-      sql << Subscription.active.joins(:plan)
-        .merge(Plan.yearly)
-        .merge(Plan.where(bill_charges_monthly: true))
-        .select(:id).to_sql
-
-      # We are on the first day of the year
-      if today.month == 1
-        # Billed yearly
-        sql << Subscription.active.joins(:plan)
-          .merge(Plan.yearly)
-          .select(:id).to_sql
-      end
+      # NOTE: Billed monthly
+      sql << monthly_calendar
+
+      # NOTE: Bill charges monthly for yearly plans
+      sql << yearly_with_monthly_charges_calendar
+
+      # NOTE: Billed yearly and we are on the first day of the year
+      sql << yearly_calendar if today.month == 1
     end
 
+    # NOTE: Anniversary subscriptions
+    sql << weekly_anniversary
+    sql << monthly_anniversary
+    sql << yearly_with_monthly_charges_anniversary
+    sql << yearly_anniversary
+
     Subscription.where("id in (#{sql.join(' UNION ')})")
   end
+
+  def weekly_calendar
+    Subscription.active.joins(:plan)
+      .calendar
+      .merge(Plan.weekly)
+      .select(:id).to_sql
+  end
+
+  def monthly_calendar
+    Subscription.active.joins(:plan)
+      .calendar
+      .merge(Plan.monthly)
+      .select(:id).to_sql
+  end
+
+  def yearly_with_monthly_charges_calendar
+    Subscription.active.joins(:plan)
+      .calendar
+      .merge(Plan.yearly.where(bill_charges_monthly: true))
+      .select(:id).to_sql
+  end
+
+  def yearly_calendar
+    Subscription.active.joins(:plan)
+      .calendar
+      .merge(Plan.yearly)
+      .select(:id).to_sql
+  end
+
+  def weekly_anniversary
+    Subscription.active.joins(:plan)
+      .anniversary
+      .merge(Plan.weekly)
+      .where('EXTRACT(ISODOW FROM subscriptions.subscription_date) = ?', today.wday)
+      .select(:id).to_sql
+  end
+
+  def monthly_anniversary
+    days = [today.day]
+
+    # If today is the last day of the month and month count less than 31 days,
+    # we need to take all days up to 31 into account
+    ((today.day + 1)..31).each { |day| days << day } if today.day == today.end_of_month.day
+
+    Subscription.active.joins(:plan)
+      .anniversary
+      .merge(Plan.monthly)
+      .where('DATE_PART(\'day\', subscriptions.subscription_date) IN (?)', days)
+      .select(:id).to_sql
+  end
+
+  def yearly_anniversary
+    # Billed yearly
+    days = [today.day]
+
+    # If we are not in leap year and we are on 28/02 take 29/02 into account
+    days << 29 if !Date.leap?(today.year) && today.day == 28 && today.month == 2
+
+    Subscription.active.joins(:plan)
+      .anniversary
+      .merge(Plan.yearly)
+      .where('DATE_PART(\'month\', subscriptions.subscription_date) = ?', today.month)
+      .where('DATE_PART(\'day\', subscriptions.subscription_date) IN (?)', days)
+      .select(:id).to_sql
+  end
+
+  def yearly_with_monthly_charges_anniversary
+    days = [today.day]
+
+    # If today is the last day of the month and month count less than 31 days,
+    # we need to take all days up to 31 into account
+    ((today.day + 1)..31).each { |day| days << day } if today.day == today.end_of_month.day
+
+    Subscription.active.joins(:plan)
+      .anniversary
+      .merge(Plan.yearly.where(bill_charges_monthly: true))
+      .where('DATE_PART(\'day\', subscriptions.subscription_date) IN (?)', days)
+      .select(:id).to_sql
+  end
 end