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<?php

class Rounding_mode
{
    const HALF_UP = PHP_ROUND_HALF_UP;
    const HALF_DOWN = PHP_ROUND_HALF_DOWN;
    const HALF_EVEN = PHP_ROUND_HALF_EVEN;
    const HALF_ODD = PHP_ROUND_HALF_ODD;
    const ROUND_UP = 5;
    const ROUND_DOWN = 6;
    const HALF_FIVE = 7;

    public static function get_rounding_options()
    {
        $CI =& get_instance();
        $CI->load->helper('language');
        $class = new ReflectionClass(__CLASS__);
        $result = array();
        foreach($class->getConstants() as $key => $value)
        {
            $result[$value] = lang(strtolower('ENUM_'. $key));
        }
        return $result;
    }

    public static function get_rounding_code_name($code)
    {
        $CI =& get_instance();
        $CI->load->helper('language');

        if (empty($code))
        {
            return lang('common_unknown');
        }

        return Rounding_mode::get_rounding_options()[$code];
    }

    public static function get_html_rounding_options()
    {
        $CI =& get_instance();
        $CI->load->helper('language');
        $x = '';
        foreach (Rounding_mode::get_rounding_options() as $option => $label)
        {
            $x .= "<option value='$option'>".$label."</option>";
        }
        return $x;
    }

    public static function round_number($rounding_mode, $amount, $decimals)
    {
        if($rounding_mode == Rounding_mode::ROUND_UP)
        {
            $fig = (int) str_pad('1', $decimals, '0');
            $rounded_total = (ceil($amount * $fig) / $fig);
        }
        elseif($rounding_mode == Rounding_mode::ROUND_DOWN)
        {
            $fig = (int) str_pad('1', $decimals, '0');
            $rounded_total = (floor($amount * $fig) / $fig);
        }
        elseif($rounding_mode == Rounding_mode::HALF_FIVE)
        {
            $rounded_total = round($amount / 5) * 5;
        }
        else
        {
            $rounded_total = round ( $amount, $decimals, $rounding_mode);
        }

        return $rounded_total;
    }
}