khosb/modules/tax/classes/Tax.php

<?php defined('SYSPATH') or die('No direct access allowed.');

/**
 * This class provides a tax information
 *
 * @package    Tax
 * @category   Helpers
 * @author     Deon George
 * @copyright  (c) 2009-2013 Open Source Billing
 * @license    http://dev.osbill.net/license.html
 */
class Tax {
	public static function add($value) {
		return Currency::round($value+static::amount($value));
	}

	/**
	 * Return the total of tax for an amount
	 */
	public static function amount($value) {
		return Currency::round(static::total(Company::instance()->country()->id,NULL,$value));
	}

	/**
	 * Return array of taxes
	 *
	 * @param $cid
	 * @param $zone
	 * @param $value
	 * @return array Tax Information
	 */
	public static function detail($cid,$zone,$value=0) {
		$tax = ORM::factory('Tax')
			->where('country_id','=',$cid)
			->and_where('zone','=',$zone)
			->find_all();

		$taxes = array();
		foreach ($tax as $to) {
			$total = array();

			$total['id'] = $to->id;
			$total['description'] = $to->description;
			$total['amount'] = $to->rate*$value;
			$total['rate'] = $to->rate;

			array_push($taxes,$total);
		}

		return $taxes;
	}

	// Calculate the tax amount
	public static function total($cid,$zone,$value) {
		$total = 0;

		foreach (static::detail($cid,$zone,$value) as $tax)
			$total += $tax['amount'];

		return $total;
	}
}
?>