DouKaku?

<?php
function Amida($file_path)
{
    if (!file_exists($file_path)) {
        return NULL;
    }
    $lines = file($file_path);
    $org = array_shift($lines);
    $p = $org;
    foreach ($lines as $line) {
        for ($i = 1; $i < strlen(trim($line)); $i+=2) {
            if ($line[$i] == '-') {
                $sub = array($p[$i+1]=>$p[$i-1], $p[$i-1]=>$p[$i+1]);
                $p = strtr($p, $sub);
            }
        }
    }
    return $org.implode('', $lines).$p;
}
?>