Transliterate cyrillic file names and replace spaces with "_"

//input
 Емец - Мефодий Булаев 1 - Маг полуночи - 2004.fb2

private function translit($string) { $charlist = array( "А"=>"A","Б"=>"B","В"=>"V","Г"=>"G", "Д"=>"D","Е"=>"E","Ж"=>"J","З"=>"Z","И"=>"I", "Й"=>"Y","К"=>"K","Л"=>"L","М"=>"M","Н"=>"N", "О"=>"O","П"=>"P","Р"=>"R","С"=>"S","Т"=>"T", "У"=>"U","Ф"=>"F","Х"=>"H","Ц"=>"TS","Ч"=>"CH", "Ш"=>"SH","Щ"=>"SCH","Ъ"=>"","Ы"=>"YI","Ь"=>"", "Э"=>"E","Ю"=>"YU","Я"=>"YA","а"=>"a","б"=>"b", "в"=>"v","г"=>"g","д"=>"d","е"=>"e","ж"=>"j", "з"=>"z","и"=>"i","й"=>"y","к"=>"k","л"=>"l", "м"=>"m","н"=>"n","о"=>"o","п"=>"p","р"=>"r", "с"=>"s","т"=>"t","у"=>"u","ф"=>"f","х"=>"h", "ц"=>"ts","ч"=>"ch","ш"=>"sh","щ"=>"sch","ъ"=>"y", "ы"=>"yi","ь"=>"","э"=>"e","ю"=>"yu","я"=>"ya"," "=>"_" ); 
return strtr($string,$charlist); } 
//output 
Emets_-_Mefodiy_Bulaev_1_-_Mag_polunochi_-_2004.fb2