pictshare/storage-controllers/altfolder.controller.php

<?php 

class AltfolderStorage implements StorageController
{
    function isEnabled()
    {
        return (defined('ALT_FOLDER') && ALT_FOLDER && is_dir(ALT_FOLDER));
    }
    
    function hashExists($hash)
    {
        $altname=ALT_FOLDER.DS.$hash;
		return file_exists($altname);
    }

    function pullFile($hash)
    {
        $altname=ALT_FOLDER.DS.$hash;
		if(file_exists($altname))
		{
            mkdir(ROOT.DS.'data'.DS.$hash);
            copy($altname,ROOT.DS.'data'.DS.$hash.DS.$hash);

            //and don't forget to add it to the duplicate detection system
            addSha1($hash,sha1_file($altname));
		}
    }

    function pushFile($hash)
    {
        $altname=ALT_FOLDER.DS.$hash;
        $orig = ROOT.DS.'data'.DS.$hash.DS.$hash;
		if(file_exists($orig) && !$this->hashExists($hash))
		{
            copy($orig,$altname);
		}
    }

    function deleteFile($hash)
    {
        $altname=ALT_FOLDER.DS.$hash;
		if(file_exists($altname))
		{
			unlink($altname);
		}
    }
}