Convert Number To Word For Nigerian Currency

gistfile1.txt

function convertNumberToWordsForNigeria($number){

    /*
        SOURCE: https://gist.github.com/hay-wire/97486dba296cd78ac7ba
    */

    //A function to convert numbers into Indian readable words with Cores, Lakhs and Thousands.
        $words = array(
            '0'=> '' ,'1'=> 'one' ,'2'=> 'two' ,'3' => 'three','4' => 'four','5' => 'five',
            '6' => 'six','7' => 'seven','8' => 'eight','9' => 'nine','10' => 'ten',
            '11' => 'eleven','12' => 'twelve','13' => 'thirteen','14' => 'fouteen','15' => 'fifteen',
            '16' => 'sixteen','17' => 'seventeen','18' => 'eighteen','19' => 'nineteen','20' => 'twenty',
            '30' => 'thirty','40' => 'fourty','50' => 'fifty','60' => 'sixty','70' => 'seventy',
            '80' => 'eighty','90' => 'ninty');

    //First find the length of the number
        $number_length = strlen($number);
    //Initialize an empty array
        $number_array = array(0,0,0,0,0,0,0,0,0);        
        $received_number_array = array();

    //Store all received numbers into an array
        for($i=0;$i<$number_length;$i++){    
            $received_number_array[$i] = substr($number,$i,1);    
        }
    //Populate the empty array with the numbers received - most critical operation
        for($i=9-$number_length,$j=0;$i<9;$i++,$j++){ 
            $number_array[$i] = $received_number_array[$j]; 
        }
        $number_to_words_string = "";
    //Finding out whether it is teen ? and then multiply by 10, example 17 is seventeen, so if 1 is preceeded with 7 multiply 1 by 10 and add 7 to it.
        for($i=0,$j=1;$i<9;$i++,$j++){
        //"01,23,45,6,78"
        //"00,10,06,7,42"
        //"00,01,90,0,00"
            if($i==0 || $i==2 || $i==4 || $i==7){
                if($number_array[$j]==0 || $number_array[$i] == "1"){
                    $number_array[$j] = intval($number_array[$i])*10+$number_array[$j];
                    $number_array[$i] = 0;
                }

            }
        }
        $value = "";
        for($i=0;$i<9;$i++){
            if($i==0 || $i==2 || $i==4 || $i==7){    
                $value = $number_array[$i]*10; 
            }
            else{ 
                $value = $number_array[$i];    
            }            
            if($value!=0)         {    $number_to_words_string.= $words["$value"]." "; }
            if($i==1 && $value!=0){    $number_to_words_string.= "Million "; }
            if($i==3 && $value!=0){    $number_to_words_string.= "Hundred Thousand ";    }
            if($i==5 && $value!=0){    $number_to_words_string.= "Thousand "; }
            if($i==6 && $value!=0){    $number_to_words_string.= "Hundred "; }            
        }
        if($number_length>9){ $number_to_words_string = "Sorry This does not support more than 99 Million Naira"; }
        return ucwords(strtolower($number_to_words_string) . "Naira" . " Only.");
    }