require 'rexml/document'

module ActiveMerchant #:nodoc:
  module Billing #:nodoc:
    # Public: For more information on the Eway Gateway please visit their
    # {Developers Area}[http://www.eway.com.au/developers/api/direct-payments]
    class EwayGateway < Gateway
      self.live_url = 'https://www.eway.com.au'

      self.money_format = :cents
      self.supported_countries = ['AU', 'NZ', 'GB']
      self.supported_cardtypes = [:visa, :master, :american_express, :diners_club]
      self.homepage_url = 'http://www.eway.com.au/'
      self.display_name = 'eWAY'

      # Public: Create a new Eway Gateway.
      # options - A hash of options:
      #           :login     - Your Customer ID.
      #           :password  - Your XML Refund Password that you
      #                        specified on the Eway site. (optional)
      def initialize(options = {})
        requires!(options, :login)
        super
      end

      def purchase(money, creditcard, options = {})
        requires_address!(options)

        post = {}
        add_creditcard(post, creditcard)
        add_address(post, options)
        add_customer_id(post)
        add_invoice_data(post, options)
        add_non_optional_data(post)
        add_amount(post, money)
        post[:CustomerEmail] = options[:email]

        commit(purchase_url(post[:CVN]), money, post)
      end

      def refund(money, authorization, options={})
        post = {}

        add_customer_id(post)
        add_amount(post, money)
        add_non_optional_data(post)
        post[:OriginalTrxnNumber] = authorization
        post[:RefundPassword] = @options[:password]
        post[:CardExpiryMonth] = nil
        post[:CardExpiryYear] = nil

        commit(refund_url, money, post)
      end

      private
      def requires_address!(options)
        raise ArgumentError.new("Missing eWay required parameters: address or billing_address") unless (options.has_key?(:address) or options.has_key?(:billing_address))
      end

      def add_creditcard(post, creditcard)
        post[:CardNumber]  = creditcard.number
        post[:CardExpiryMonth]  = sprintf("%.2i", creditcard.month)
        post[:CardExpiryYear] = sprintf("%.4i", creditcard.year)[-2..-1]
        post[:CustomerFirstName] = creditcard.first_name
        post[:CustomerLastName]  = creditcard.last_name
        post[:CardHoldersName] = creditcard.name

        post[:CVN] = creditcard.verification_value if creditcard.verification_value?
      end

      def add_address(post, options)
        if address = options[:billing_address] || options[:address]
          post[:CustomerAddress]    = [ address[:address1], address[:address2], address[:city], address[:state], address[:country] ].compact.join(', ')
          post[:CustomerPostcode]   = address[:zip]
        end
      end

      def add_customer_id(post)
        post[:CustomerID] = @options[:login]
      end

      def add_invoice_data(post, options)
        post[:CustomerInvoiceRef] = options[:order_id]
        post[:CustomerInvoiceDescription] = options[:description]
      end

      def add_amount(post, money)
        post[:TotalAmount] = amount(money)
      end

      def add_non_optional_data(post)
        post[:Option1] = nil
        post[:Option2] = nil
        post[:Option3] = nil
        post[:TrxnNumber] = nil
      end

      def commit(url, money, parameters)
        raw_response = ssl_post(url, post_data(parameters))
        response = parse(raw_response)

        Response.new(success?(response),
          message_from(response[:ewaytrxnerror]),
          response,
          :authorization => response[:ewaytrxnnumber],
          :test => test?
        )
      end

      def success?(response)
        response[:ewaytrxnstatus] == "True"
      end

      def parse(xml)
        response = {}
        xml = REXML::Document.new(xml)
        xml.elements.each('//ewayResponse/*') do |node|
          response[node.name.downcase.to_sym] = normalize(node.text)
        end unless xml.root.nil?

        response
      end

      def post_data(parameters = {})
        xml   = REXML::Document.new
        root  = xml.add_element("ewaygateway")

        parameters.each do |key, value|
          root.add_element("eway#{key}").text = value
        end
        xml.to_s
      end

      def message_from(message)
        return '' if message.blank?
        MESSAGES[message[0,2]] || message
      end

      # Make a ruby type out of the response string
      def normalize(field)
        case field
        when "true"   then true
        when "false"  then false
        when ""       then nil
        when "null"   then nil
        else field
        end
      end

      def purchase_url(cvn)
        suffix = test? ? 'xmltest/testpage.asp' : 'xmlpayment.asp'
        gateway_part = cvn ? 'gateway_cvn' : 'gateway'
        "#{live_url}/#{gateway_part}/#{suffix}"
      end

      def refund_url
        suffix = test? ? 'xmltest/refund_test.asp' : 'xmlpaymentrefund.asp'
        "#{live_url}/gateway/#{suffix}"
      end

      MESSAGES = {
        "00" => "Transaction Approved",
        "01" => "Refer to Issuer",
        "02" => "Refer to Issuer, special",
        "03" => "No Merchant",
        "04" => "Pick Up Card",
        "05" => "Do Not Honour",
        "06" => "Error",
        "07" => "Pick Up Card, Special",
        "08" => "Honour With Identification",
        "09" => "Request In Progress",
        "10" => "Approved For Partial Amount",
        "11" => "Approved, VIP",
        "12" => "Invalid Transaction",
        "13" => "Invalid Amount",
        "14" => "Invalid Card Number",
        "15" => "No Issuer",
        "16" => "Approved, Update Track 3",
        "19" => "Re-enter Last Transaction",
        "21" => "No Action Taken",
        "22" => "Suspected Malfunction",
        "23" => "Unacceptable Transaction Fee",
        "25" => "Unable to Locate Record On File",
        "30" => "Format Error",
        "31" => "Bank Not Supported By Switch",
        "33" => "Expired Card, Capture",
        "34" => "Suspected Fraud, Retain Card",
        "35" => "Card Acceptor, Contact Acquirer, Retain Card",
        "36" => "Restricted Card, Retain Card",
        "37" => "Contact Acquirer Security Department, Retain Card",
        "38" => "PIN Tries Exceeded, Capture",
        "39" => "No Credit Account",
        "40" => "Function Not Supported",
        "41" => "Lost Card",
        "42" => "No Universal Account",
        "43" => "Stolen Card",
        "44" => "No Investment Account",
        "51" => "Insufficient Funds",
        "52" => "No Cheque Account",
        "53" => "No Savings Account",
        "54" => "Expired Card",
        "55" => "Incorrect PIN",
        "56" => "No Card Record",
        "57" => "Function Not Permitted to Cardholder",
        "58" => "Function Not Permitted to Terminal",
        "59" => "Suspected Fraud",
        "60" => "Acceptor Contact Acquirer",
        "61" => "Exceeds Withdrawal Limit",
        "62" => "Restricted Card",
        "63" => "Security Violation",
        "64" => "Original Amount Incorrect",
        "66" => "Acceptor Contact Acquirer, Security",
        "67" => "Capture Card",
        "75" => "PIN Tries Exceeded",
        "82" => "CVV Validation Error",
        "90" => "Cutoff In Progress",
        "91" => "Card Issuer Unavailable",
        "92" => "Unable To Route Transaction",
        "93" => "Cannot Complete, Violation Of The Law",
        "94" => "Duplicate Transaction",
        "96" => "System Error"
      }
    end
  end
end