<?php
/* --------------------------------------------------------------
  xtc_get_tax_rate.inc.php 2019-05-09
  Gambio GmbH
  http://www.gambio.de
  Copyright (c) 2019 Gambio GmbH
  Released under the GNU General Public License (Version 2)
  [http://www.gnu.org/licenses/gpl-2.0.html]
  --------------------------------------------------------------


  based on:
  (c) 2000-2001 The Exchange Project  (earlier name of osCommerce)
  (c) 2002-2003 osCommerce(general.php,v 1.225 2003/05/29); www.oscommerce.com
  (c) 2003	 nextcommerce (xtc_get_tax_rate.inc.php,v 1.3 2003/08/13); www.nextcommerce.org
  (c) 2003 XT-Commerce - community made shopping http://www.xt-commerce.com ($Id: xtc_get_tax_rate.inc.php 862 2005-04-16 10:26:29Z mz $)

  Released under the GNU General Public License
  ----------------------------------------------------------------------------------------- */

require_once DIR_FS_INC . 'country_eu_status_by_country_id.inc.php';

function xtc_get_tax_rate($p_class_id, $p_country_id = -1, $p_zone_id = -1, $p_customer_b2b = -1)
{
	static $t_tax_rates_array, $showPriceTax, $addTaxOt;

	$c_class_id = (int)$p_class_id;
	$c_country_id = (int)$p_country_id;
	$c_zone_id = (int)$p_zone_id;

	if(($c_country_id === -1 || $c_country_id === 0) && ($c_zone_id === -1 || $c_zone_id === 0))
	{
		$c_country_id = (isset($_SESSION['customer_country_id'])) ? (int)$_SESSION['customer_country_id'] : (int)STORE_COUNTRY;
		
		if(isset($_SESSION['customer_zone_id']))
		{
			$c_zone_id = (int)$_SESSION['customer_country_id'];
		}
		elseif(!isset($_SESSION['customer_zone_id']) && (!isset($_SESSION['customer_country_id']) || $_SESSION['customer_country_id'] == STORE_COUNTRY))
		{
			$c_zone_id = (int)STORE_ZONE;
		}
		else
		{
			$c_zone_id = 0;
		}
	}

	if($_SESSION['customers_status']['customers_status_id'] === '0')
	{
		$c_country_id = (int)STORE_COUNTRY;
		$c_zone_id = (int)STORE_ZONE;
	}
	elseif(country_eu_status_by_country_id($c_country_id) == true)
	{
		if($p_customer_b2b != -1)
		{
			$t_customer_b2b = $p_customer_b2b;
		}
		elseif(isset($_SESSION['customer_b2b_status']) == true)
		{
			$t_customer_b2b = $_SESSION['customer_b2b_status'];
		}
		else
		{
			$t_customer_b2b = false;
		}

		if($t_customer_b2b == true)
		{
			// OVERWRITE country and zone, if customer is B2B in EU
			$c_country_id = (int)STORE_COUNTRY;
			$c_zone_id = (int)STORE_ZONE;
		}
	}


	$t_key = $c_class_id . '_' . $c_country_id . '_' . $c_zone_id;
	
	if($t_tax_rates_array !== null && isset($t_tax_rates_array[$t_key]))
	{
		return $t_tax_rates_array[$t_key];
	}
	else
	{
		// START VAT-ID BASED TAX CALCULATION
		
		if($showPriceTax === null && $addTaxOt === null)
		{
			$query = 'SELECT 
							customers_status_show_price_tax, 
							customers_status_add_tax_ot 
						FROM customers_status
						WHERE
							customers_status_id = ' . (int)$_SESSION['customers_status']['customers_status_id'] . ' AND 
							language_id = ' . (int)$_SESSION['languages_id'];
			
			$result = xtc_db_query($query);
			$row    = xtc_db_fetch_array($result);
			
			$showPriceTax = $row['customers_status_show_price_tax'];
			$addTaxOt     = $row['customers_status_add_tax_ot'];
		}
		
		// skip calculation if not activated or store is not located in the EU
		// skip admin customer group, because of tax calculation problems in the backend 
		if(CALCULATE_TAX_BASED_ON_VAT_ID === 'true'
		   && country_eu_status_by_country_id((int)STORE_COUNTRY)
		   && $_SESSION['customers_status']['customers_status_id'] !== '0'
		)
		{
			// skip calculation if tax display is already deactivated by customer group configuration
			// skip calculation if customer has no account (no VAT-ID)
			if(isset($_SESSION['customer_id']) && !empty($_SESSION['customer_id']))
			{
				// get customer VAT-ID information
				/* @var CustomerService $customerService */
				$customerService   = StaticGXCoreLoader::getService('Customer');
				$customer          = $customerService->getCustomerById(new IdType($_SESSION['customer_id']));
				$vatId             = (string)$customer->getVatNumber();
				$validVatId        = true;
				$shippingCountryId = $c_country_id;
				
				if(ACCOUNT_COMPANY_VAT_CHECK === 'true')
				{
					$validVatId = $customer->getVatNumberStatus() === 1;
				}
				
				// country ID of customer's default address or selected location - lowest priority
				if(isset($_SESSION['customer_country_id']))
				{
					$shippingCountryId = (int)$_SESSION['customer_country_id'];
				}
				else
				{
					/* @var AddressBookService $addressBookService */
					$addressBookService = StaticGXCoreLoader::getService('AddressBook');
					$customerAddress    = $addressBookService->findAddressById(new IdType((int)$_SESSION['customer_default_address_id']));
					
					if($customerAddress !== null)
					{
						$shippingCountryId = $customerAddress->getCountry()->getId();
					}
				}
				
				// country ID of selected shipping address in checkout process - highest priority
				if(isset($_SESSION['sendto']))
				{
					/* @var AddressBookService $addressBookService */
					$addressBookService = StaticGXCoreLoader::getService('AddressBook');
					$customerAddress    = $addressBookService->findAddressById(new IdType((int)$_SESSION['sendto']));
					
					if($customerAddress !== null)
					{
						$shippingCountryId = $customerAddress->getCountry()->getId();
					}
				}
				
				// set no tax if valid VAT ID is given and shipping country differs from store country and is in the EU
				if(!empty($vatId) && $validVatId && $shippingCountryId !== (int)STORE_COUNTRY
				   && country_eu_status_by_country_id($shippingCountryId))
				{
					$t_tax_rates_array[$t_key] = 0;
					
					$_SESSION['customers_status']['customers_status_show_price_tax'] = '0';
					$_SESSION['customers_status']['customers_status_add_tax_ot']     = '0';
					
					return 0;
				}
			}
			
			// reset tax configuration to customer group default
			$_SESSION['customers_status']['customers_status_show_price_tax'] = $showPriceTax;
			$_SESSION['customers_status']['customers_status_add_tax_ot']     = $addTaxOt;
		}
		// END VAT-ID BASED TAX CALCULATION
		
		$t_sql = 'SELECT SUM(tax_rate) AS tax_rate 
					FROM
						' . TABLE_TAX_RATES . ' tr 
					LEFT JOIN ' . TABLE_ZONES_TO_GEO_ZONES . ' za ON (tr.tax_zone_id = za.geo_zone_id) 
					LEFT JOIN ' . TABLE_GEO_ZONES . ' tz ON (tz.geo_zone_id = tr.tax_zone_id) 
					WHERE
						(za.zone_country_id IS NULL OR 
							za.zone_country_id = "0" OR 
							za.zone_country_id = "' . (int)$c_country_id . '") AND 
						(za.zone_id IS NULL OR 
							za.zone_id = "0" OR 
							za.zone_id = "' . (int)$c_zone_id . '") AND 
						tr.tax_class_id = "' . (int)$c_class_id . '" 
					GROUP BY tr.tax_priority';
		$t_result = xtc_db_query($t_sql);
		
		if(xtc_db_num_rows($t_result, true))
		{
			$t_tax_multiplier = 1.0;
			while($t_tax_array = xtc_db_fetch_array($t_result, true))
			{
				$t_tax_multiplier *= 1.0 + ($t_tax_array['tax_rate'] / 100);
			}
			
			$t_tax_rate = ($t_tax_multiplier - 1.0) * 100;
			
			$t_tax_rates_array[$t_key] = $t_tax_rate;
			
			return $t_tax_rate;
		}
		else
		{
			$t_tax_rates_array[$t_key] = 0;
			
			return 0;
		}
	}
}