<?php

/*
 * Copyright (C) 2006 Google Inc.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

 /**
  * Used to create the merchant callback results when a 
  * merchant-calculated feedback structure is received.
  * 
  * Multiple results are generated depending on the possible
  * combinations for shipping options and address ids
  * 
  * More info: {@link http://code.google.com/apis/checkout/developer/index.html#understanding_merchant_calculation_results}
  */
  // refer to demo/responsehandler.php for generating these results
  class GoogleMerchantCalculations {
     var $results_arr;
     var $currency;
     var $schema_url = "http://checkout.google.com/schema/2";

    /**
     * @param string $currency the currency used for the calculations,
     *                         one of "USD" or "GBP"
     * 
     * @return void
     */
    function GoogleMerchantCalculations($currency = "USD") {
      $this->results_arr = array();
      $this->currency = $currency;
    }

    /**
     * Add a result of a merchant calculation to the response to be sent.
     * 
     * @param GoogleResult $results the result of a particular merchant 
     *                              calculation
     * @return void
     */
    function AddResult($results) {
      $this->results_arr[] = $results;
    }

    /**
     * Builds the merchant calculation response xml to be sent to
     * Google Checkout.
     * 
     * @return string the response xml
     */
    function GetXML() {
      require_once('xml-processing/gc_xmlbuilder.php');

      $xml_data = new gc_XmlBuilder();
      $xml_data->Push('merchant-calculation-results', 
          array('xmlns' => $this->schema_url));
      $xml_data->Push('results');

      foreach($this->results_arr as $result) {
        if ($result->shipping_name != "") {
          $xml_data->Push('result', array('shipping-name' => 
              $result->shipping_name, 'address-id' => $result->address_id));
          $xml_data->Element('shipping-rate', $result->ship_price, 
              array('currency' => $this->currency));
          $xml_data->Element('shippable', $result->shippable);
        } else
          $xml_data->Push('result', array('address-id' => $result->address_id));

        if ($result->tax_amount != "")   
          $xml_data->Element('total-tax', $result->tax_amount, 
              array('currency' => $this->currency));

        if ((count($result->coupon_arr) != 0) || 
            (count($result->giftcert_arr) != 0) )  {
          $xml_data->Push('merchant-code-results');

          foreach($result->coupon_arr as $curr_coupon) {
            $xml_data->Push('coupon-result');  
            $xml_data->Element('valid', $curr_coupon->coupon_valid);
            $xml_data->Element('code', $curr_coupon->coupon_code);
            $xml_data->Element('calculated-amount', $curr_coupon->coupon_amount,
                array('currency'=> $this->currency));
            $xml_data->Element('message', $curr_coupon->coupon_message);
            $xml_data->Pop('coupon-result');  
          }
          foreach($result->giftcert_arr as $curr_gift) {
            $xml_data->Push('gift-result');  
            $xml_data->Element('valid', $curr_gift->gift_valid);
            $xml_data->Element('code', $curr_gift->gift_code);
            $xml_data->Element('calculated-amount', $curr_gift->gift_amount, 
                array('currency'=> $this->currency));
            $xml_data->Element('message', $curr_gift->gift_message);
            $xml_data->Pop('gift-result');  
          }
          $xml_data->Pop('merchant-code-results');
        }
        $xml_data->Pop('result');  
      }
      $xml_data->Pop('results');
      $xml_data->Pop('merchant-calculation-results'); 
      return $xml_data->GetXML();
    }
  }