Files
openfoodnetwork/app/models/calculator/flat_percent_per_item.rb

33 lines
1.0 KiB
Ruby

require_dependency 'spree/calculator'
require 'spree/localized_number'
class Calculator::FlatPercentPerItem < Spree::Calculator
# Spree's FlatPercentItemTotal calculator sums all amounts, and then calculates a percentage
# on them.
# In the cart, we display line item individual amounts rounded, so to have consistent
# calculations we do the same internally. Here, we round adjustments at the individual
# item level first, then multiply by the item quantity.
extend Spree::LocalizedNumber
preference :flat_percent, :decimal, default: 0
attr_accessible :preferred_flat_percent
localize_number :preferred_flat_percent
def self.description
I18n.t(:flat_percent_per_item)
end
def compute(object)
line_items_for(object).sum do |li|
unless li.price.present? && li.quantity.present?
raise ArgumentError, "object must respond to #price and #quantity"
end
value = (li.price * BigDecimal(preferred_flat_percent.to_s) / 100.0).round(2)
value * li.quantity
end
end
end