Country Hierarchy Maker

country_hierarchy

$data['USA'] = ['Alabama' => ['Montgomery','Birmingham'],'Arizona' => ['Phoenix','Mesa','Gilbert','Bonn']];
$data['Germany'] = ['West Germany' => ['Bonn','Cologne']];
$data['Canada'] = ['West Germany' => ['Bonn','Cologne']];

function getHierarchy($location, $data, $start = 0){
    $totalCountries = count($data);

    //Get Array Keys of rows eg countries.
    $keys = array_keys($data);
    $hierarchy = [];
    $break = false;

    //Loop Through Countries
    for($i = $start; $i < $totalCountries; $i++){
        //If we have found the country then return it.
        if($location == $keys[$i]) return [$keys[$i]];
        $hierarchy[] = $keys[$i];
        foreach($data[$keys[$i]] as $city => $places){

            // if we have found the city then return it with country.
            if($city == $location){
                $hierarchy[] = $city;
                $break = true;
                break;
            }

            // if we have found the place in our places array then return it with country -> city -> place.
            if(in_array($location, $places)){
                $hierarchy[] = $city;
                $hierarchy[] = $location;
                $break = true;
            }
        }
        // Reset Hirarcy if we do not found our location in previews country.
        if(!$break){
            $hierarchy = [];
        } else {
            break;
        }
        
    }
    
    if($i < $totalCountries){
        $after = getHierarchy($location, $data, ($i+1));
        if(!empty($after)){
            array_unshift($after, $hierarchy);
            return $after;
        } else {
            return [$hierarchy];
        }
    } 
    
    return ![$hierarchy];
}

$found = getHierarchy('Mesa', $data);
echo '<pre>'.print_r($found,1).'</pre>';