class Extenso
{
    // Types
    const MONEY = 1;
    const INTEGER = 2;

    // Variables
    public $amount;
    private $type;

    public function __construct($amount = 0, $type = self::INTEGER)
    {
        $this->type = $type;

        switch ($type) {
            case self::MONEY:
                $amount = (float) $amount;
                $this->amount = array(
                    "reais"     => intval($amount),
                    "centavos"  => intval($amount * 100) % 100
                );

                break;
            default:
                $this->amount = (int) $amount;
        }
    }

    // classes numéricas
    private function get_classes($amount)
    {
        $class = [];

        $total = floor(floor(log($amount, 10))/3)+1;

        for ($i=1;$i<=$total;$i++) {
            $class[$i-1] = $amount % pow(10, 3*$i) - array_sum($class);
        }

        return $class;
    }

    private function print($value)
    {
        $f = new NumberFormatter("pt-BR", NumberFormatter::SPELLOUT);
        return $f->format($value);
    }

    private function join(&$str, $classes, $i)
    {
        if(!($classes[$i-1] % pow(10, 3*$i-1)))
            $str .= " e ";
        elseif($classes[$i-1] < pow(10, 3*$i-1))
            $str .= " e ";
        else
            $str .= ", ";
    }

    private function formatting($amount)
    {
        $str = null;

        $classes = $this->get_classes($amount);

        for ($i=count($classes)-1;$i>0;$i--) {
            $value = $classes[$i];

            if(!$value) continue;

            $str .= $this->print($value);

            $this->join($str, $classes, $i);
        }

        if (($classes[0])) {
            $str .= $this->print($classes[0]);
        } else {
            $str = trim(substr($str, 0, -2));
        }

        return $str;
    }

    public function __toString()
    {
        if ($this->type == self::MONEY) {
            $amount = $this->amount['reais'];
        } else {
            $amount = $this->amount;
        }

        $str = $this->formatting($amount) . " reais";

        if ($this->amount['centavos'] > 0)
            $str .= " e " . $this->formatting($this->amount['centavos']) . " centavos";

        return $str;
    }
}