Wordpress: Send Email after any Post type status change

functions.php

/**
 *
 * https://codex.wordpress.org/Post_Status_Transitions
 *
 * Send email to admin after user create new product from frontend form.
 * Send emails on products publication
 * @param WP_Post $post
 * 
 * 
 */ 
function ns_send_emails_on_new_event($post){
	
    $emails = "test@test.com"; 
    $title = wp_strip_all_tags(get_the_title($post->ID));
    $url = get_edit_post_link( $post->ID, $context );
    $message = "A new product has been created on in your site.\nProduct Title: \n{$title} \nProduct URL: \n{$url}";
 	if(get_post_type($post->ID) === 'product') {		
   		 wp_mail($emails, "New product has been created", $message);		
	}
}   
add_action('future_to_pending', 'ns_send_emails_on_new_event');
add_action('new_to_pending', 'ns_send_emails_on_new_event');
add_action('draft_to_pending', 'ns_send_emails_on_new_event');
add_action('auto-draft_to_pending', 'ns_send_emails_on_new_event');


add_action('pending_to_publish', 'ns_send_emails_on_deal_publish');
function ns_send_emails_on_deal_publish($post){ 
	$author_id=$post->post_author;
	$emails = get_the_author_meta( 'user_email' , $author_id ); ; //If you want to send to site administrator, use $emails = get_option('admin_email');
	$title = wp_strip_all_tags(get_the_title($post->ID));
	$url = get_permalink( $post->ID );
	$message = "Your Deal is Live.\n Check Deal: \n{$url}";
	if(get_post_type($post->ID) === 'product') 
	{
		 wp_mail($emails, "Your Deal on Site Name is Live: {$title}", $message);
	}
}