Try to handle incorrectly prefixed region codes (#19327)

* Try to handle incorrectly prefixed region codes

* Adds test for prefix region codes

2 files changed, 30 insertions, 1 deletions

diff --git a/plugins/GeoIp2/LocationProvider/GeoIp2/Php.php b/plugins/GeoIp2/LocationProvider/GeoIp2/Php.php
index 44423661e8..cf10439ab4 100644
--- a/plugins/GeoIp2/LocationProvider/GeoIp2/Php.php
+++ b/plugins/GeoIp2/LocationProvider/GeoIp2/Php.php
@@ -251,7 +251,16 @@ class Php extends GeoIp2
         if (is_array($lookupResult->subdivisions) && count($lookupResult->subdivisions) > 0) {
             $subdivisions = $lookupResult->subdivisions;
             $subdivision = $this->determinSubdivision($subdivisions, $result[self::COUNTRY_CODE_KEY]);
-            $result[self::REGION_CODE_KEY] = $subdivision->isoCode ? strtoupper($subdivision->isoCode) : $this->determineRegionIsoCodeByNameAndCountryCode($subdivision->name, $result[self::COUNTRY_CODE_KEY]);
+            $subdivisionIsoCode = $subdivision->isoCode ? strtoupper($subdivision->isoCode) : '';
+
+            // In some cases the region code might be returned including the country code
+            // e.g. AE-DU instead of only DU. In that case we remove the prefix
+            // see https://github.com/matomo-org/matomo/issues/19323
+            if (0 === strpos($subdivisionIsoCode, $result[self::COUNTRY_CODE_KEY] . '-')) {
+                $subdivisionIsoCode = substr($subdivisionIsoCode, strlen($result[self::COUNTRY_CODE_KEY]) + 1);
+            }
+
+            $result[self::REGION_CODE_KEY] = $subdivisionIsoCode ? : $this->determineRegionIsoCodeByNameAndCountryCode($subdivision->name, $result[self::COUNTRY_CODE_KEY]);
             $result[self::REGION_NAME_KEY] = $subdivision->name;
         }
     }
diff --git a/plugins/GeoIp2/tests/Integration/LocationProviderTest.php b/plugins/GeoIp2/tests/Integration/LocationProviderTest.php
index ea1fc20927..3798092694 100644
--- a/plugins/GeoIp2/tests/Integration/LocationProviderTest.php
+++ b/plugins/GeoIp2/tests/Integration/LocationProviderTest.php
@@ -58,6 +58,26 @@ class LocationProviderTest extends \PHPUnit\Framework\TestCase
         ], $result);
     }
 
+    public function testGeoIP2CityWithIncorrectlyPrefixedRegionIsoCode()
+    {
+        // The IP 88.88.88.88 will return a region code that is prefixed with the country code, e.g. US-NJ instead of NJ
+        $locationProvider = new GeoIp2\Php(['loc' => ['GeoIP2-City.mmdb'], 'isp' => []]);
+        $result = $locationProvider->getLocation(['ip' => '88.88.88.88']);
+
+        $this->assertEquals([
+            'continent_name' => 'North America',
+            'continent_code' => 'NA',
+            'country_code' => 'US',
+            'country_name' => 'United States',
+            'city_name' => 'Englewood Cliffs',
+            'lat' => 40.892,
+            'long' => -73.947,
+            'postal_code' => null,
+            'region_code' => 'NJ',
+            'region_name' => 'New Jersey',
+        ], $result);
+    }
+
     public function testGeoIP2Country()
     {
         $locationProvider = new GeoIp2\Php(['loc' => ['GeoIP2-Country.mmdb'], 'isp' => []]);