OMGM Code

<?php

class GpxParser{

public function parse($file){
  if (!($fp = fopen($file, "r"))) {
    die("could not open XML input");
  }

  $contents = fread($fp, filesize($file));
  $p = xml_parser_create();
  $res = xml_parse_into_struct($p, $contents, $values, $tags);
  if ($res == 0)
          die("Couldn't parse ".$file);

  xml_parser_free($p);

  $wpArr = array();
  $trkArr = array();

  foreach($tags as $key=>$tagIdxes){
    if($key=='WPT'){
       $wpArr = $this->createWPT($tagIdxes, $values);
    }
    elseif($key=='TRK'){
       $trkArr = $this->createTracks($tagIdxes, $values);
    }
  }

  $res = array();
  $res["WPT"] = $wpArr;
  $res["TRK"] = $trkArr;
  
  return $res;
}

private function createTracks($tagIdxes, $values){
  $trackArr = array();
  foreach($tagIdxes as $idx){
    $tag = $values[$idx];
    if( $tag["type"] == 'open' ){
      $segmentArr = $this->createTrack($idx + 1, $values);
      $trackArr[] = $segmentArr;
    }
  }
  return $trackArr;
}

private function createTrack($startIdx, $values){
  $segmentArr = array();
  for($i = $startIdx; ;$i++){
    $tag = $values[$i];
    if( $tag["type"] == 'open' && $tag["tag"] == 'TRKSEG'){
      $segmentArr[] = $this->createTrackSegment($i+1, $values);
    }
    elseif( $tag["type"] == 'close' && $tag["tag"] == 'TRK'){
      break;
    }
  }
  return $segmentArr;
}

private function createTrackSegment($startIdx, $values){
  $trackPoints = array();
  for($i = $startIdx; ; $i++){
    $tag = $values[$i];
    if( $tag["tag"] == 'TRKPT' && is_array($tag["attributes"]) ){
           $lat = $tag["attributes"]["LAT"];
           $lng = $tag["attributes"]["LON"];
           $trackPoints[] = array("LAT"=>$lat, "LNG"=>$lng);
    }
    elseif( $tag["type"] == 'close' && $tag["tag"] == 'TRKSEG'){
      break;
    }
  }
  return $trackPoints;
}

private function createWPT($tagIdxes, $values){
  $latLngArr = array();

  foreach($tagIdxes as $idx){
     $tag = $values[$idx];
     if($tag["type"] == 'open'){
        if( is_array($tag["attributes"])){
           $lat = $tag["attributes"]["LAT"];
           $lng = $tag["attributes"]["LON"];
           $latLngArr[] = array("LAT"=>$lat, "LNG"=>$lng);
        }
     }
  }
  return $latLngArr;
}

}
?>