# Bens amazing 'list of book barcodes -> folder of book cover images' convertor.
# March, 2010
#
# Freeware. Use it for the benefit of mankind (or not, it's up to you).
# Credit Ben Dunham [www.toasta.com] if you feel like it.

require 'ftools'
require 'rubygems'
require 'amazon/aws/search'
require 'open-uri'
include Amazon::AWS
include Amazon::AWS::Search

# Initialise the image file name counter
i = 0

# Read in the barcodes from the file generated by RedLaser
barcodes = File.read('barcodes.txt')

# Loop over every line separated barcode in the file
barcodes.split("\n").each do |barcode|
  
  # Wrap everything in a big ol exception handler. Not too bothered if something goes wrong.
  begin
    # Construct all the AWS gubbins
    lookup = ItemLookup.new('ISBN', { 'ItemId' => barcode, 'SearchIndex' => 'Books' })
    group = ResponseGroup.new('Large')
    request = Request.new
    
    # Only check the Amazon UK site
    request.locale = 'uk'
    
    # Perform the AWS lookup
    response = request.search(lookup, group)
    
    # Check if any items were found
    if response.item_lookup_response[0].items
      
      # I want all images to be sequentially numbered, so only increment on successful AWS lookup
      i += 1
      
      # Download the small Amazon book cover
      image = open(response.item_lookup_response[0].items[0].item[0].small_image.url)
      
      # Write the cover to a file in the Books directory
      File.open('../books/' + i.to_s + '.jpg','w'){|f| f.write(image.read) }
      
      # Close the downloaded image handle (not sure if this is required, but seems like a good idea!)
      image.close
    end
  rescue
     # No image found. Oh well, we tried.
  end
end