Custom WordPress function - coding exam submission

functions.php

<?php
/**
 * A wordpress function that triggers #publish button onClick
 * when on a post page (admin); then:
 * 1) gets all custom_fields of an extended Pod that are marked Required, of the current post_type
 * 2) checks if all the required fields have a value, if not, throws an error
 * 3) checks if custom_field XYZ has a value between 50 & 80, if not throws an error
 * 4) changes post_status to "publish"
 * 5) re-directs to homepage.
 */
function my_custom_function() {
    // check if on a post page
    $post_type = get_post_type();
    if ($post_type != null) :
    // trigger onClick
    ?>
    
    <script type="text/javascript">
        (function($) {
            $('#publish').onClick(function() {
                
                <?php
                // get all custom_fields of an extended pod that are marked Required
                // of current post_type
                $pod = pods( 'mypod', $post_type );
                $fields = $pod->fields();
            	$required = array_filter( $fields, function( $item ) { 
            		return ( $item["options"]["required"] == "1" );
            	} );
                // check if all of them has a value else throw an error
                while ( $pod->fetch() ) {
                    if ( $pod->display( 'name' ) == "" ) {
                        wp_die( "Error!" );
                    }
                }
                // check if 50 <= custom_field XYZ <= 80 else throw an error
                $field = $pod->fields( 'custom_field' );
                if ( $field < 50 || $field > 80 ) {
                    wp_die( "Error!" );
                }
                // change post_status to "publish"
                $post = get_post();
                wp_update_post( $post );
                // redirect to homepage
                wp_redirect( '/' );
                exit;
                ?>
                
            });
        })(jQuery);
    </script>
    
    <?php
    endif;
}
add_action( 'admin_footer', 'my_custom_function' );