<?php
/**
 * 
 * Sanitizes a file-upload information array.
 * 
 * @category Solar
 * 
 * @package Solar_Filter
 * 
 * @author Paul M. Jones <hide@address.com>
 * 
 * @license http://opensource.org/licenses/bsd-license.php BSD
 * 
 * @version $Id: SanitizeUpload.php 3732 2009-04-29 17:27:56Z pmjones $
 * 
 */
class Solar_Filter_SanitizeUpload extends Solar_Filter_Abstract
{
    /**
     * 
     * Sanitizes a file-upload information array.  If no file has been 
     * uploaded, the information will be returned as null.
     * 
     * @param array $value An array of file-upload information.
     * 
     * @return mixed The sanitized upload information array, or null.
     * 
     */
    public function sanitizeUpload($value)
    {
        // if the value is not required, and is blank, sanitize to null
        $null = ! $this->_filter->getRequire() &&
                $this->_filter->validateBlank($value);
                
        if ($null) {
            return null;
        }
        
        // has to be an array
        if (! is_array($value)) {
            return null;
        }
        
        // presorted list of expected keys
        $expect = array('error', 'name', 'size', 'tmp_name', 'type');
        
        // remove unexpected keys
        foreach ($value as $key => $val) {
            if (! in_array($key, $expect)) {
                unset($value[$key]);
            }
        }
        
        // sort the list of remaining actual keys
        $actual = array_keys($value);
        sort($actual);
        
        // make sure the expected and actual keys match up
        if ($expect != $actual) {
            return null;
        }
        
        // if all the non-error values are empty, still null
        $empty = empty($value['name']) &&
                 empty($value['size']) &&
                 empty($value['tmp_name']) &&
                 empty($value['type']);
                 
        if ($empty) {
            return null;
        }
        
        // everything looks ok, return as-is
        return $value;
    }
}