class Variant < ActiveRecord::Base
  belongs_to :product
  has_many :property_values, :dependent => :destroy, :after_add => :compare_stringified_prop_vals, :after_remove => :compare_stringified_prop_vals

  acts_as_ferret :fields => { 'short_code' => { :boost => 2 }, 'property_values_string' => { :boost => 1 } }

  def self.active_scope(allow_inactive = false, &block)
    raise ArgumentError, "block expected" if block.nil?
    return block.call if allow_inactive
    Variant.with_scope(:find => {:conditions => ['variants.active = ?', true]}, &block)
  end

  def unit_price=(arg)
    upc = arg.to_f * 100
    raise ArgumentError, "strange unit price value #{arg.inspect}" unless (upc % 1) == 0
    self.unit_price_cents = upc
  end

  def unit_price
    (self.unit_price_cents * 1.0) / 100
  end

  def fq_path(parent = product())
    parent.fq_path + ';' + self.id.to_s
  end

  # return the PropertyValue#text_value for a given Property or property_id
  def property_text_value(prop)
    (property_value_for(prop) or return nil).text_value
  end

  # return the PropertyValue object for a given Property or property_id
  # bah - this could be more efficient
  def property_value_for(prop)
    prop = prop.id if prop.is_a? Property
    property_values.detect {|x| x.property_id == prop }
  end

  # creates or updates property_values given a hash of property_id => text_value pairs
  def property_text_values=(ptv_hash)
    ptv_hash.each do |key, value|
      if propval = property_value_for(key.to_i)
        propval.update_attributes(:text_value => value)
      else
        property_values.build(:property_id => key, :text_value => value)
      end
    end
  end

  def stringify_property_values
    text_values = []
    self.property_values.each do |pv|
      text_values << pv.text_value unless pv.text_value.strip.blank?
    end
    self.property_values_string = text_values.join(", ").squeeze(" ")
  end

  def compare_stringified_prop_vals
    old_val = String.new(self.stringify_property_values)
    self.stringify_property_values
    self.save unless old_val == self.stringify_property_values
  end

end