How to remove .php extension from URL and trailing slash in nginx

Question

I am trying to remove the .php extension from the URL and at the same time, I have to allow trailing slash. I am attaching my code below. My code successfully removed the .php extension but not adding a trailing slash. Please help.

location / {
    try_files $uri $uri.html $uri/ @extensionless-php;
    index index.php;
}

location @extensionless-php {
    rewrite ^/(.*)/$ /$1 permanent;
    try_files $uri $uri/ $uri.html $uri.php$is_args$query_string;
}

Here are the lines of codes I have added in my nginx.conf

TL;DR

#case : 
# 1. example.com/about-us.php       =>  example.com/about-us/
# 2. example.com/about-us           =>  example.com/about-us/
# 3. example.com/about-us?s=search  =>  example.com/about-us/?s=search