CheckPalindrome2.php

<?php

/**
 * This is a simple way to check palindrome string
 * using php strrev() function
 * make it simple
 *
 * @param  string  $string
 * @param  bool  $caseInsensitive
 * @return string
 * @throws \Exception
 */
function checkPalindromeString(string $string, bool $caseInsensitive = true): string
{
    //removing spaces
    $string = trim($string);

    if (empty($string)) {
        throw new \Exception('You are given empty string. Please give a non-empty string value');
    }

    /**
     * for case-insensitive
     * lowercase string conversion
     */
    if ($caseInsensitive) {
        $string = strtolower($string);
    }

    if ($string !== strrev($string)) {
        return $string . " - not a palindrome string." . PHP_EOL;
    }

    return $string . " - a palindrome string." . PHP_EOL;
}