Set taxes per country for MarketPress. Please make sure that "mp_manage_price_tax/tax_rate" filter has been added in mp_manage_price_tax() function

wpmudev-mp-countries-taxrates.php

<?php
/*
Plugin Name: Custom taxes for MarketPress
Plugin URI: https://premium.wpmudev.org/
Description: Overrides taxes for products and cart. Can use custom tax rates per country. You can use "WPMUDEV_MP_Country_Taxes/get_countries_info" filter to deit countries and rates
Author: Panos Lyrakis @ WPMUDEV
Author URI: https://premium.wpmudev.org/
License: GPLv2 or later
*/


/**
* Set taxes per country for MarketPress
*
* Requires 
* 	1. MarketPress
*	2. filter "mp_manage_price_tax/tax_rate" in mp_manage_price_tax function
*/

if( ! class_exists( 'WPMUDEV_MP_Country_Taxes' ) ){

	class WPMUDEV_MP_Country_Taxes
	{	
		private static $_instance = null;	

		public static function get_instance() {
	        if ( is_null( self::$_instance ) ) {
	            self::$_instance = new WPMUDEV_MP_Country_Taxes();
	        }

	        return self::$_instance;
	    }
		
		private function __construct(){
			//add_filter( 'mp/taxes_tax_amount', array( $this, 'set_tax' ) , 10, 5 );		
			add_filter( 'mp_manage_price_tax/tax_rate', array( $this, 'set_tax' ) , 10, 5 );
			add_filter( 'mp_tax_rate', array( $this, 'set_tax' ), 10 );
		}


		//public function set_tax( $amount, $price_with_tax_pre_compound, $key, $ar, $applied_rates ){
		public function set_tax( $tax_rate, $tax_inclusive = null, $include_tax_to_price = null, $special_tax = null, $special_fixed_tax = null ){

			$country_code = $this->get_country_code();

			$new_tax_rate = $this->get_country_tax( $country_code );

			return $new_tax_rate ? $new_tax_rate : $tax_rate;
			
		}


		public function get_country_tax( $country_code, $region=null ){

            //TODO
            //Check regions also

			$countries_taxes = $this->get_countries_info();
			
			if( ! isset( $countries_taxes[ $country_code ] ) || ! is_numeric( $countries_taxes[ $country_code ] ) ){
				return false;
			}

			return $countries_taxes[ $country_code ] / 100;		

		}

		
		public function get_countries_info(){

			//TODO
			// Check if country code used is 3 chars and in such case filter to 2

			return apply_filters( 'WPMUDEV_MP_Country_Taxes/get_countries_info', array(
				'CA' => 15, 	// Canada
				'GR' => 24		// Greece
			));

			/*
			//TODO
			return apply_filters( 'WPMUDEV_MP_Country_Taxes/get_countries_info', array(
				'CA' => array( 	// Canada
					'default'		=> 15,
					'state_code_a'	=> 16.7,
					'state_code_b'	=> 14.5,
				),
				'GR' => array(	// Greece
					'default'		=> 24
				)
			));
			*/

		}


		public function get_country_code(){

			$use_user_info = true;

			if( ! is_user_logged_in() ) $use_user_info = false;
			else{
				$billling_info = mp_get_user_address( 'billing' ); 
				if( ! isset( $billling_info[ 'country' ] ) || $billling_info[ 'country' ] == '' ){
					$use_user_info = false;
				}
			}

			if( $use_user_info ) return $billling_info[ 'country' ];

			$WPMUDEV_RemoteAddress = new WPMUDEV_RemoteAddress;
			$IP = $WPMUDEV_RemoteAddress->getIpAddress();
			$location = json_decode( file_get_contents('http://freegeoip.net/json/'.$IP ), true );

			return $location['country_code'];

		}

	}


	function WPMUDEV_MP_Country_Taxes_load(){
		
		$GLOBALS['WPMUDEV_MP_Country_Taxes'] = WPMUDEV_MP_Country_Taxes::get_instance();
	}

	add_action( 'plugins_loaded', 'WPMUDEV_MP_Country_Taxes_load' );

}


if( ! class_exists( 'WPMUDEV_RemoteAddress' ) ){

	class WPMUDEV_RemoteAddress
	{
	    /**
	     * Whether to use proxy addresses or not.
	     *
	     * As default this setting is disabled - IP address is mostly needed to increase
	     * security. HTTP_* are not reliable since can easily be spoofed. It can be enabled
	     * just for more flexibility, but if user uses proxy to connect to trusted services
	     * it's his/her own risk, only reliable field for IP address is $_SERVER['REMOTE_ADDR'].
	     *
	     * @var bool
	     */
	    protected $useProxy = false;

	    /**
	     * List of trusted proxy IP addresses
	     *
	     * @var array
	     */
	    protected $trustedProxies = array();

	    /**
	     * HTTP header to introspect for proxies
	     *
	     * @var string
	     */
	    protected $proxyHeader = 'HTTP_X_FORWARDED_FOR';

	    // [...]

	    /**
	     * Returns client IP address.
	     *
	     * @return string IP address.
	     */
	    public function getIpAddress()
	    {
	        $ip = $this->getIpAddressFromProxy();
	        if ($ip) {
	            return $ip;
	        }

	        // direct IP address
	        if (isset($_SERVER['REMOTE_ADDR'])) {
	            return $_SERVER['REMOTE_ADDR'];
	        }

	        return '';
	    }

	    /**
	     * Attempt to get the IP address for a proxied client
	     *
	     * @see http://tools.ietf.org/html/draft-ietf-appsawg-http-forwarded-10#section-5.2
	     * @return false|string
	     */
	    protected function getIpAddressFromProxy()
	    {
	        if (!$this->useProxy
	            || (isset($_SERVER['REMOTE_ADDR']) && !in_array($_SERVER['REMOTE_ADDR'], $this->trustedProxies))
	        ) {
	            return false;
	        }

	        $header = $this->proxyHeader;
	        if (!isset($_SERVER[$header]) || empty($_SERVER[$header])) {
	            return false;
	        }

	        // Extract IPs
	        $ips = explode(',', $_SERVER[$header]);
	        // trim, so we can compare against trusted proxies properly
	        $ips = array_map('trim', $ips);
	        // remove trusted proxy IPs
	        $ips = array_diff($ips, $this->trustedProxies);

	        // Any left?
	        if (empty($ips)) {
	            return false;
	        }

	        // Since we've removed any known, trusted proxy servers, the right-most
	        // address represents the first IP we do not know about -- i.e., we do
	        // not know if it is a proxy server, or a client. As such, we treat it
	        // as the originating IP.
	        // @see http://en.wikipedia.org/wiki/X-Forwarded-For
	        $ip = array_pop($ips);
	        return $ip;
	    }

	    // [...]
	}

}
?>