Plings XML Sorter

<?php
# Copyright (c) 2009 David Carpenter <david@substance.coop>
# Released as free software under the MIT license,
# 
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
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# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:

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# all copies or substantial portions of the Software.

# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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# THE SOFTWARE.

/*Takes parsed plings (activity or venue) XML and sorts it by the given parameter*/
 
//To get the parsed data:
//$Plings_API_url='http://feeds.plings.net/xml.activity.php/1/la/00EY?APIKey=5A605302-FC5BC526-4473C6AB-B4D9009B-RQMKMLDM';
//$xml = simplexml_load_file($Plings_API_url);
//$originalactivities = $xml->activities->activity; 
//Example usage:
//$activities = sort_plings_xml($originalactivities,'name','desc']);
 
/*The results are automatically orderd alphabetically, and then by time*/
/*To reverse the order supply 'desc' as the third parameter in this function*/
 
function sort_plings_xml($originalactivities,$term,$order='asc') {
 
  //Set up some arrays that we can sort the data by...
  $start=array();
  $sortby =array();
  $activities=array();
 
  //Loop through the XML grabbing the info we want and pushing this into new arrays
  foreach($originalactivities as $activity){
 
         switch ($term) {
            case 'name':
       			  array_push ($sortby, htmlspecialchars(stripslashes($activity->Name)));
       			 	break;
       		  case 'VenueName':
       			  array_push ($sortby, htmlspecialchars(stripslashes($activity->venue->Name)));
       			  break;
       		  case 'ProviderName':
       			  array_push ($sortby, htmlspecialchars(stripslashes($activity->provider->Name)));
       			  break;
       			case 'cost':
       			  array_push ($sortby, htmlspecialchars(stripslashes($activity->Cost)));
       		  	break;
 
   		  	case 'la';
   		  	    array_push($sortby, htmlspecialchars(stripslashes($activity->venue->LAName)));
   		  	    break;
   		  	case 'ward';
   		  	    array_push($sortby, htmlspecialchars(stripslashes($activity->venue->WardName)));
   		  	    break;
            }
 
            //start time
              array_push($start, htmlspecialchars(stripslashes($activity->Starts)));
           // echo $start[$j];
            //Make an $activities array cos I don't understand the $xml array!         
              array_push($activities, $activity);
  }
  //Debug and experiments      
  //print_r($sortby);
  //print_r($start);
  //$start = array_reverse($start);
 
 
  //If order is 'desc' then once sorted we reverse the array - but this means we get the data sorted by e.g. Name alphabetically reversed, and 
  //with the start time showing the last instance to the first - so we probably want, first instance to the last...
  //Reverse the order of the start times....
  if ($order == 'desc') {
        $start=array_reverse($start);
  }
 
  //We've got our arrays now, so lets sort it
  //Sorts $activities by our term, then by time - cool, 
  array_multisort($sortby, $start,$activities);
 
  //print_r($activities);
 
  //re-order our acticvities array descending if required...
  if ($order == 'desc') {
        $activities=array_reverse($activities);
  }
 
  //This is for checking...
  /*
  $sorted=array();   
  foreach ($activities as $activity){
  array_push($sorted, $activity->Name.$activity->Starts);
  }
  print_r($sorted);
  */
  //Done!
  return $activities;
 
}
 
 
//Example usage...
//Get and Parse the XML
$Plings_API_url='http://feeds.plings.net/xml.activity.php/1/la/00EY?APIKey=5A605302-FC5BC526-4473C6AB-B4D9009B-RQMKMLDM';
$xml = simplexml_load_file($Plings_API_url);
$originalactivities = $xml->activities->activity; 
 
//Sort by activity name..
$sorted=sort_plings_xml($originalactivities,'name');
 
  $list=array();   
  foreach ($sorted as $activity){
  array_push($list, $activity->Name.' '.$activity->Starts);
  }
  print_r($list);
 
//Sort by activity Cost - descending
$sorted=sort_plings_xml($originalactivities,'cost','desc');
  $list=array();   
  foreach ($sorted as $activity){
  array_push($list, $activity->Cost.' '.$activity->Starts);
  }
  print_r($list);
 
//Sort by VenueName 
$sorted=sort_plings_xml($originalactivities,'VenueName');
  $list=array();   
  foreach ($sorted as $activity){
  array_push($list, $activity->venue->Name.' '.$activity->Starts);
  }
  print_r($list);
 
//Sort by ProviderName - descending
$sorted=sort_plings_xml($originalactivities,'ProviderName','desc');
  $list=array();   
  foreach ($sorted as $activity){
  array_push($list, $activity->provider->Name.' '.$activity->Starts);
  }
  print_r($list);
?>