add file size to downloads

template.php

//FIELD PREPROCESSING MADE POSSIBLE FOR ANY FIELD
function theme_process_field(&$variables) {
  $function = 'autorijschool_process_field__'. $variables['element']['#field_name'];
  if(function_exists($function)) {
    $variables = $function($variables);
  }
}

//ADDS FILESIZE TO A DOCUMENTS FIELD
function theme_process_field__field_documents (&$variables) {
  foreach($variables['items'] as $key => $val) {
    $val['#file']->filename = $val['#file']->filename . " (" . __format_file_fize_size($val['#file']->filesize) . ")";
  }
  
  return $variables;
}

//FORMATS FILESIZE INTO SOMETHING READABLE
function __format_file_fize_size( $size, $display_bytes=false ) {
  if( $size < 1024 )
    $filesize = $size . ' bytes';
  elseif( $size >= 1024 && $size < 1048576 )
    $filesize = round( $size/1024, 2 ) . ' KB';

  elseif( $size >= 1048576 )
    $filesize = round( $size/1048576, 2 ) . ' MB';

  if( $size >= 1024 && $display_bytes )
    $filesize = $filesize . ' (' . $size . ' bytes)';

  return $filesize;
}