Adding tax based on Zip need help with tax.php class file..

[fourmat]

Hi Guys,

I'm trying to implement a tax by zip code modification. There are a few of them out there, but the NY County Tax Rate contribution seemed to do exactly what I needed.

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The instructions are pretty straight forward, but there are some major differences in the includes/functions/general.php files between MS2.2 and OSCMax RC3.

Specifically, the function tep_get_tax_rate( function is broken off into the /includes/classes/tax.php file. There are changes in the coding that are throwing me for a loop. This is the only location that there seems to be a major difference.

I was wondering if someone might be able to take a peek at the difference in code and help me make the adjustments.

These are the instructions for making the changes:

in includes/functions/general.php

CHANGE TO:
--------------------------------------------------------------------------------
<?php
////BOF New York State Tax Modification
// Returns the tax rate for a zone / class
// TABLES: tax_rates, zones_to_geo_zones

  function tep_get_tax_rate($class_id, $country_id = -1, $zone_id = -1, $tax_zip_code ="") {
    global $customer_zone_id, $customer_country_id;

    if ( ($country_id == -1) && ($zone_id == -1) ) {
      if (!tep_session_is_registered('customer_id')) {
        $country_id = STORE_COUNTRY;
        $zone_id = STORE_ZONE;
      } else {
        $country_id = $customer_country_id;
        $zone_id = $customer_zone_id;
      }
    }

		$tax_zip_code = trim($tax_zip_code); // This trims any spaces they may have entered after/begin the zip
		if(strlen($tax_zip_code) > 5){
			$tax_zip_code = substr($tax_zip_code,0,5); // This cuts the zip down to the first 5 digits
		}

    $county_taxquery = tep_db_query("select zip_tax_rate from  " . TABLE_ZIPTAX . " where zip_code =  '" . $tax_zip_code . "'");
    if (tep_db_num_rows($county_taxquery)) {

    $county_tax_query = tep_db_fetch_array($county_taxquery);
    $county_taxrate = $county_tax_query['zip_tax_rate'];
    } else {
    $county_taxrate = "";
    }

    $tax_query = tep_db_query("select sum(tax_rate) as tax_rate from " . TABLE_TAX_RATES . " tr left join " . TABLE_ZONES_TO_GEO_ZONES . " za on (tr.tax_zone_id = za.geo_zone_id) left join " . TABLE_GEO_ZONES . " tz on (tz.geo_zone_id = tr.tax_zone_id) where (za.zone_country_id is null or za.zone_country_id = '0' or za.zone_country_id = '" . (int)$country_id . "') and (za.zone_id is null or za.zone_id = '0' or za.zone_id = '" . (int)$zone_id . "') and tr.tax_class_id = '" . (int)$class_id . "' group by tr.tax_priority");
    if (tep_db_num_rows($tax_query)) {
      $tax_multiplier = 0.0;
      while ($tax = tep_db_fetch_array($tax_query)) {
        $tax_multiplier += $tax['tax_rate'];
      }
      if ($county_taxrate != "") {
	      $tax_multiplier += $county_taxrate;
      }
      return $tax_multiplier;
    } else {

if ($county_taxrate != "") {
	      $tax_multiplier = $county_taxrate;
		return $tax_multiplier;
      }
      else
	{
	return 0;
	}

      
    }
  }


////
// Return the tax description for a zone / class
// TABLES: tax_rates;
/* test */
  function tep_get_tax_description($class_id, $country_id, $zone_id, $tax_zip_code = "") {
    $county_taxquery = tep_db_query("select zip_tax_rate, zipcounty from  " . TABLE_ZIPTAX . " where zip_code =  '" . $tax_zip_code . "'");
    if (tep_db_num_rows($county_taxquery)) {
    $county_tax_query = tep_db_fetch_array($county_taxquery);
    $county_taxrate = number_format($county_tax_query['zip_tax_rate'], 2, '.', '');
    $county = $county_tax_query['zipcounty'];
    } else {
    $county_taxrate = "";
    $county = "";
    }

    $tax_query = tep_db_query("select tax_description from " . TABLE_TAX_RATES . " tr left join " . TABLE_ZONES_TO_GEO_ZONES . " za on (tr.tax_zone_id = za.geo_zone_id) left join " . TABLE_GEO_ZONES . " tz on (tz.geo_zone_id = tr.tax_zone_id) where (za.zone_country_id is null or za.zone_country_id = '0' or za.zone_country_id = '" . (int)$country_id . "') and (za.zone_id is null or za.zone_id = '0' or za.zone_id = '" . (int)$zone_id . "') and tr.tax_class_id = '" . (int)$class_id . "' order by tr.tax_priority");
    if (tep_db_num_rows($tax_query)) {
      $tax_description = '';
      while ($tax = tep_db_fetch_array($tax_query)) {
        $tax_description .= $tax['tax_description'] . ' + ';
      }
      $tax_description = substr($tax_description, 0, -3);
      if ($county_taxrate != "") {
	       $tax_description .= " + $county County Tax $county_taxrate%";
      }
      return $tax_description;

    } else {
	
	if ($county_taxrate != "") {
	      $tax_description = "$county County Tax $county_taxrate%";
		return $tax_description;

      }
	else {
      return TEXT_UNKNOWN_TAX_RATE;
	}
    }
  }

                                    ////////EOF New York State Tax Modification

-----------------------------------------------------------------

IN the OSCMAX General.php:

////
// Returns the tax rate for a zone / class
// TABLES: tax_rates, zones_to_geo_zones
  function tep_get_tax_rate($class_id, $country_id = -1, $zone_id = -1) {
// BOF: MOD - Separate Pricing Per Customer, show_tax modification
    global $customer_zone_id, $customer_country_id, $osC_Tax, $sppc_customer_group_tax_exempt;

     if(!tep_session_is_registered('sppc_customer_group_tax_exempt')) {
     $customer_group_tax_exempt = '0';
     } else {
     $customer_group_tax_exempt = $sppc_customer_group_tax_exempt;
     }

     if ($customer_group_tax_exempt == '1') {
	     return 0;
     }
 return $osC_Tax->getTaxRate($class_id, $country_id, $zone_id);
}

// EOF: MOD - Separate Pricing Per Customer, show_tax modification


////
// Return the tax description for a zone / class
// TABLES: tax_rates;
  function tep_get_tax_description($class_id, $country_id, $zone_id) {
// BOF: MOD - Separate Pricing Per Customer, show_tax modification
  	 global $osC_Tax;
  	 return $osC_Tax->getTaxRateDescription($class_id, $country_id, $zone_id);
// EOF: MOD - Separate Pricing Per Customer, show_tax modification
    }

And in the OSCMax class/tax.php:

 class osC_Tax {
    var $tax_rates;

// class constructor
    function osC_Tax() {
      $this->tax_rates = array();
    }

// class methods
    function getTaxRate($class_id, $country_id = -1, $zone_id = -1) {
// LINE ADDED: Bugfix 0000036 
    global $customer_zone_id, $customer_country_id;
    if ( ($country_id == -1) && ($zone_id == -1) ) {
      if (!tep_session_is_registered('customer_id')) {
        $country_id = STORE_COUNTRY;
        $zone_id = STORE_ZONE;
      } else {
        $country_id = $customer_country_id;
        $zone_id = $customer_zone_id;
      }
    }

      if (isset($this->tax_rates[$class_id][$country_id][$zone_id]['rate']) == false) {
        $tax_query = tep_db_query("select sum(tax_rate) as tax_rate from " . TABLE_TAX_RATES . " tr left join " . TABLE_ZONES_TO_GEO_ZONES . " za on (tr.tax_zone_id = za.geo_zone_id) left join " . TABLE_GEO_ZONES . " tz on (tz.geo_zone_id = tr.tax_zone_id) where (za.zone_country_id is null or za.zone_country_id = '0' or za.zone_country_id = '" . (int)$country_id . "') and (za.zone_id is null or za.zone_id = '0' or za.zone_id = '" . (int)$zone_id . "') and tr.tax_class_id = '" . (int)$class_id . "' group by tr.tax_priority");
        if (tep_db_num_rows($tax_query)) {
          $tax_multiplier = 1.0;
          while ($tax = tep_db_fetch_array($tax_query)) {
            $tax_multiplier *= 1.0 + ($tax['tax_rate'] / 100);
          }

          $tax_rate = ($tax_multiplier - 1.0) * 100;
        } else {
          $tax_rate = 0;
        }

        $this->tax_rates[$class_id][$country_id][$zone_id]['rate'] = $tax_rate;
      }

      return $this->tax_rates[$class_id][$country_id][$zone_id]['rate'];
    }

    function getTaxRateDescription($class_id, $country_id, $zone_id) {
      if (isset($this->tax_rates[$class_id][$country_id][$zone_id]['description']) == false) {
        $tax_query = tep_db_query("select tax_description from " . TABLE_TAX_RATES . " tr left join " . TABLE_ZONES_TO_GEO_ZONES . " za on (tr.tax_zone_id = za.geo_zone_id) left join " . TABLE_GEO_ZONES . " tz on (tz.geo_zone_id = tr.tax_zone_id) where (za.zone_country_id is null or za.zone_country_id = '0' or za.zone_country_id = '" . (int)$country_id . "') and (za.zone_id is null or za.zone_id = '0' or za.zone_id = '" . (int)$zone_id . "') and tr.tax_class_id = '" . (int)$class_id . "' order by tr.tax_priority");
        if (tep_db_num_rows($tax_query)) {
          $tax_description = '';

          while ($tax = tep_db_fetch_array($tax_query)) {
            $tax_description .= $tax['tax_description'] . ' + ';
          }

          $this->tax_rates[$class_id][$country_id][$zone_id]['description'] = substr($tax_description, 0, -3);
        } else {
          $this->tax_rates[$class_id][$country_id][$zone_id]['description'] = TEXT_UNKNOWN_TAX_RATE;
        }
      }

      return $this->tax_rates[$class_id][$country_id][$zone_id]['description'];
    }
  }

The biggest issue that I have in understanding this is that there is a difference in coding where the class uses a lot of "this->" statement. I'm not sure how those work in comparison to the standard "return=0" type of statement. Any help would be greatly appreciated. Thanks!