require "rexml/document"
require "rubygems"
require "builder"
class Item
  attr_reader :code, :name, :quantity, :price
  def initialize(code, name, quantity, price)
    @code = code
    @name = name
    @quantity = quantity
    @price = price
  end

  def validate_item(items)
    items.each do |item|
      return false if item.code == self.code
    end
    true
  end
end

class Customer
  attr_reader :name, :street, :city, :zip, :country, :state
  def initialize(name, street, city, zip, country, state)
    @name = name
    @street = street
    @city = city
    @zip =  zip
    @country = country
    @state = state
  end
  def validate_customer(customers)
    customers.each do |customer|
      return false if customer.name == self.name
    end
    true
  end
end

def load_xml(file)
  customers = []
  items_list = []
  File.open(file,"r") do |file|
    doc = REXML::Document.new(file)
    doc.root.elements.each do |order|
      address = order.elements["address[@type='billing']"]
      customer = Customer.new(address.elements["name"].text, address.elements["street"].text, address.elements["city"].text, address.elements["zip"].text, address.elements["country"].text, address.elements["state"].text)
      customers << customer if customer.validate_customer(customers)
      #tady to je druhy zpusob jak pracovat s xml, radeji ukazu oba at to chapes :D
      doc.each_element('//orders//order//items//item') do |items|
        item = Item.new(items.attributes["code"],items.elements["name"].text, items.elements["quantity"].text, items.elements["price"].text)
        items_list << item if item.validate_item(items_list)
      end
    end
  end
  return customers, items_list
end

def print_xml(file,customers, items)
  File.open(file,"w+") do |file|
    xml = Builder::XmlMarkup.new({:target => file, :indent => 2})
    xml.instruct!
    xml.database do
      xml.customers do
        customers.each do |customer|
          xml.customer do
            xml.name(customer.name)
            xml.street(customer.street)
            xml.city(customer.city)
            xml.state(customer.state)
            xml.zip(customer.zip)
            xml.country(customer.country)
          end
        end
      end
      xml.items do
        items.each do |item|
          xml.item({:code => item.code}) do
            xml.name(item.name)
            xml.price(item.price)
          end
        end
      end
    end
  end
end


puts "Nacitam XML"
customers, items = load_xml("orders.xml")
puts "Zapisuju XML"
print_xml("output.xml",customers, items)