awesome tv show parsing

function calcMostCommonDiff($orig, $files) {
	$mismatches = array();
	$inRow = 0;
	$firstLength = strlen(reset($orig));
	$firstFile = reset($orig);

	foreach($files as $file) {
		$inRow = 0;
		
		for($i = 0; $i < $firstLength; $i++) {
			$thisChar = $firstFile{$i};
			
			if($i >= strlen($file)) continue;
			$otherChar = $file{$i};
			
			if($thisChar != $otherChar && is_numeric($thisChar) && is_numeric($otherChar)) {
				$inRow++;
				$mismatches[] = $i;
				
				if($inRow === 3) {
					$removeStart = count($mismatches);
					unset($mismatches[$removeStart - 1]);
					unset($mismatches[$removeStart - 2]);
					unset($mismatches[$removeStart - 3]);
					break;
				}
			}
			else {
				$inRow = 0;
			}
		}
	}
			
	$count = array();
	$len = count($mismatches);
	foreach($mismatches as $match) {
		$count[$match]++;
	}
		arsort($count);
	$count = array_slice(array_keys($count), 0, 2);
	
	list($pos1, $pos2) = $count;
	$ePos = ($pos1 > $pos2 ? $pos1 : $pos2);
	
	foreach(array_insert($files, reset(array_keys($orig)), reset($orig)) as $file) {
		$parts = explode('.', $file);
		$extension = array_pop($parts);
		$reconstructed = implode('.', $parts);
		$frontRemoved = ltrim(substr($reconstructed, $ePos+1), ' .,-[]_');
		$backRemoved = preg_replace("/(\[[a-z0-9]+\])/", "", $frontRemoved);
		$names[] = trim($backRemoved);
	}
	
	return array($count, $mismatches, $names);
}