Migrating a Shopify Script Creator script

# GENERATED BY THE SHOPIFY SCRIPT CREATOR APP
# Version 0.12.0

class Campaign
  def initialize(condition, *qualifiers)
    @condition = (condition.to_s + '?').to_sym
    @qualifiers = PostCartAmountQualifier ? [] : [] rescue qualifiers.compact
    @line_item_selector = qualifiers.last unless @line_item_selector
    qualifiers.compact.each do |qualifier|
      is_multi_select = qualifier.instance_variable_get(:@conditions).is_a?(Array)
      if is_multi_select
        qualifier.instance_variable_get(:@conditions).each do |nested_q|
          @post_amount_qualifier = nested_q if nested_q.is_a?(PostCartAmountQualifier)
          @qualifiers << qualifier
        end
      else
        @post_amount_qualifier = qualifier if qualifier.is_a?(PostCartAmountQualifier)
        @qualifiers << qualifier
      end
    end if @qualifiers.empty?
  end

  def qualifies?(cart)
    return true if @qualifiers.empty?
    @qualifiers.send(@condition) do |qualifier|
      is_selector = false
      if qualifier.is_a?(Selector) || qualifier.is_a?(Array)
        is_selector = true
      end rescue nil
      if is_selector
        raise 'Missing line item match type' if @li_match_type.nil?
        cart.line_items.send(@li_match_type) { |item| qualifier.match?(item) }
      else
        qualifier.match?(cart, @selector)
      end
    end
  end
end

class ProductTagSelector < Selector
  def initialize(match_type, match_condition, tags)
    @match_condition = match_condition
    @invert = match_type == :does_not
    @tags = tags.map(&:downcase)
  end

  def match?(line_item)
    product_tags = line_item.variant.product.tags.to_a.map(&:downcase)
    case @match_condition
      when :match
        return @invert ^ ((@tags & product_tags).length > 0)
      else
        return @invert ^ partial_match(@match_condition, product_tags, @tags)
    end
  end
end

class PercentageDiscount
  def initialize(percent, message)
    @percent = Decimal.new(percent) / 100.0
    @message = message
  end

  def apply(line_item)
    line_discount = line_item.line_price * @percent
    new_line_price = line_item.line_price - line_discount
    line_item.change_line_price(new_line_price, message: @message)
  end
end

CAMPAIGNS = [
  ConditionalDiscount.new(
    :all,
    nil,
    nil,
    ProductTagSelector.new(:does, :match, ["sale"]),
    PercentageDiscount.new(20, "20% off sale items"),
    0
  ),
].freeze

CAMPAIGNS.each do |campaign|
  campaign.run(Input.cart)
end

Output.cart = Input.cart

识别为 Percentage off，重建为 volume 类型的优惠。下面是优惠实际保存时使用的配置键，您可以逐项核对自己的重建结果。

基于我们的公开演示店铺 Meridian Goods 搭建，因此这里的每个价格都可以复现，而不必凭信任接受。下方的折扣金额，是结账时运行的同一个引擎针对这个购物车算出的结果。