mixed map in ruby

mixed_map.rb

items = { item_name_1: "Great Deal",
          item_options_2: "blah: 2",
          item_name_2: "Awesome Deal",
          item_options_1: "foo: 3",
          item_quantity_1: "1",
          item_price_2: "9.99",
          item_price_1: "9.99",
          itemCount: "2" }

def item_key_index(key)
  (index = /^item_.+_(\d+$)/.match(key)) && (index[1].to_i - 1)
end

def clean_key(key)
  key.to_s.gsub(/_(\d+$)/, '').to_sym
end

def parsed_items(items)
  items.reduce([]) do |accum, (key, val)|
    if index = item_key_index(key)
      accum[index] ||= {}
      accum[index][clean_key(key)] = val
    end
    accum
  end
end

p parsed_items(items)

#=> [{:item_name=>"Great Deal", :item_options=>"foo: 3", :item_quantity=>"1", :item_price=>"9.99"}, 
#    {:item_options=>"blah: 2", :item_name=>"Awesome Deal", :item_price=>"9.99"}]