php code to find rank of a name

rankName.php

function findRankByString($input){
	$input = strtolower($input);
	if(strlen($input) <= 1){
		return 1;
	}
  
	$chars = [];
	for ($i = 0; $i < strlen($input); $i++) {
		array_push($chars, $input[$i]);
	};
	// print_r($chars);
	
	$sortedChars = copyArray($chars);
	for ($i = 1; $i < count($sortedChars); $i++) {
		for ($j = $i; $j > 0; $j--) {
			if ($sortedChars[$j-1]>$sortedChars[$j]) { // should be lower case 
				$t = $sortedChars[$j];
				$sortedChars[$j] = $sortedChars[$j-1];
				$sortedChars[$j-1] = $t;
			};
		}
	};
	// print_r($sortedChars);
	
	$output = findPartialByCharsSorted($chars, $sortedChars) + 1;
	return $output;
}

function findPartialByCharsSorted($chars, $sortedChars, $combSumInit = 0){
	$combSum = $combSumInit;
	// print_r($tChar);
	// print_r($combSum);
	$len = count($sortedChars);
	if($len <= 0){ 
		return $combSum;
	}
	$tChar = $chars[0];
	
	for ($j = 0; $j < $len; $j++) {
		// echo "loop1";
		$doneChars = [];
		for ($i = 0; $i < count($sortedChars); $i++) {
			if($tChar == $sortedChars[$i]) {
				array_splice($chars, 0, 1);
				array_splice($sortedChars, $i, 1);
				return findPartialByCharsSorted($chars, $sortedChars, $combSum);
				// break;
			} else if ( !charInArray($sortedChars[$i], $doneChars)){
				$temp = copyArray($sortedChars);
				array_splice($temp, $i, 1);
				$combSum += permuteOver($temp);
				array_push($doneChars, $sortedChars[$i]);
			}
		}
	}
}

function permuteOver($chars){
	$n = count($chars);
	$freq = new ArrayObject();
	$deno = 1;
	if($n<=1) {return 1;}
	for ($i = 0; $i < count($chars); $i++) {
		if (isset($freq[$chars[$i]])) {
			$freq[$chars[$i]]++;
		} else{
			$freq[$chars[$i]] = 1;
		}
	}
	foreach($freq as $key => $value) {
		if($freq[$key]>1){
			$deno *= factorial($freq[$key]);
		}
	}
	return (factorial($n))/$deno;
}

function charInArray($c, $arr){
	for ($i = 0; $i < count($arr); $i++) {
		if($c==$arr[$i]){
			return true;
		}
	}
}

function factorial($x) {
	if($x==0) {
		return 1;
	}
	return $x * factorial($x-1);
}

function copyArray($a){
	$r = [];
	for ($i = 0; $i < count($a); $i++) {
		array_push($r, $a[$i]);
	}
	return $r;
}