#!/usr/bin/ruby

require 'base64'
require 'net/http'
require 'openssl'

ACCESS_KEY_ID="xxxxxxxxxxxxxxxxxxxx"
SECRET_ACCESS_KEY="xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"

# Downloads the next document from PDF Alchemy.
# Returns the documentId (String) on success, or nil on failure.
def downloadNext
  # Generate the HMAC signature.
  date=Time.now.getutc.strftime('%a, %d %b %Y %H:%M:%S GMT')
  request="/#{ACCESS_KEY_ID}/outqueue/next"
  clearText="GET\n#{ACCESS_KEY_ID}\n#{date}\n#{request}"
  signature=Base64.encode64(OpenSSL::HMAC.digest(OpenSSL::Digest::Digest.new('sha1'),SECRET_ACCESS_KEY,clearText)).strip

  # Request the next document from PDF Alchemy.
  http=Net::HTTP.new('www.pdfalchemy.com')
  http.start do
    req=Net::HTTP::Get.new(request)
    req['Date']=date
    req['X-PDF-Alchemy-Signature']=signature
    resp=http.request(req)
    if resp.is_a?(Net::HTTPSuccess) then
      filename=resp['content-disposition'].match(/filename="([^"].*)"/)[1]
      open(filename,'wb') {|io|io.write(resp.body)}
      puts "Downloaded '#{filename}'."
      return resp['X-PDF-Alchemy-ID']
    else
      puts "#{resp.code}: #{resp.message}: #{resp.body}"
      return nil
    end
  end
end

# Removes documentId from the PDF Alchemy outqueue.
def deleteDocument(documentId)
  # Generate the HMAC signature.
  date=Time.now.getutc.strftime('%a, %d %b %Y %H:%M:%S GMT')
  request="/#{ACCESS_KEY_ID}/outqueue/#{URI::escape(documentId)}"
  clearText="DELETE\n#{ACCESS_KEY_ID}\n#{date}\n#{request}"
  signature=Base64.encode64(OpenSSL::HMAC.digest(OpenSSL::Digest::Digest.new('sha1'),SECRET_ACCESS_KEY,clearText)).strip

  # Remove the document from PDF Alchemy.
  http=Net::HTTP.new('www.pdfalchemy.com')
  http.start do
    req=Net::HTTP::Delete.new(request)
    req['Date']=date
    req['X-PDF-Alchemy-Signature']=signature
    resp=http.request(req)
    if resp.is_a?(Net::HTTPSuccess) then puts "Deleted '#{documentId}'"
    else puts "#{resp.code}: #{resp.message}: #{resp.body}"
    end
  end
end

while (documentId=downloadNext) != nil
  deleteDocument(documentId)
end