Change Permalink Structure for a Custom Post Type

add_filter( 'post_link', 'rudr_post_type_permalink', 20, 3 );
add_filter( 'post_type_link', 'rudr_post_type_permalink', 20, 3 );

function rudr_post_type_permalink( $permalink, $post_id, $leavename ) {

	$post_type_name = 'product'; // post type name, you can find it in admin area or in register_post_type() function
	$post_type_slug = 'product'; // the part of your product URLs, not always matches with the post type name
	$tax_name = 'product_cat'; // the product categories taxonomy name

	$post = get_post( $post_id );

	if( false === strpos( $permalink, $post_type_slug ) || $post->post_type !== $post_type_name ) { // do not make changes if the post has different type or its URL doesn't contain the given post type slug
		return $permalink;
	}

	$terms = wp_get_object_terms( $post->ID, $tax_name ); // get all terms (product categories) of this post (product)

	if( ! is_wp_error( $terms ) && $terms ) { // rewrite only if this product has categories
		$permalink = str_replace( $post_type_slug, $terms[0]->slug, $permalink );
	}

	return $permalink;
}

add_filter( 'request', 'rudr_post_type_request', 1, 1 );

function rudr_post_type_request( $query ){
	global $wpdb;

	$post_type_name = 'product'; // specify your own here
	$tax_name = 'product_cat'; // and here
	
	if( empty( $query[ 'attachment' ] ) ) {
		return $query;
	}
	
	$slug = $query[ 'attachment' ]; // when we change the post type link, WordPress thinks that these are attachment pages

	// get the post with the given type and slug from the database
	$post_id = $wpdb->get_var(
		$wpdb->prepare(
			"
			SELECT ID
			FROM $wpdb->posts
			WHERE post_name = %s
			AND post_type = %s
			"
		),
		$slug,
		$post_type_name
	);
	
	if( ! $post_id ) {
		return $query;
	}

	$terms = wp_get_object_terms( $post_id, $tax_name ); // our post should have the terms

	// change the query
	if( ! is_wp_error( $terms ) && $terms ) {

		unset( $query[ 'attachment' ] );
		$query[ $post_type_name ] = $slug;
		$query[ 'post_type' ] = $post_type_name;
		$query[ 'name' ] = $slug;

	}

	return $query;
}

add_action( 'template_redirect', 'rudr_post_type_redirect' );

function rudr_post_type_redirect() {

	global $post, $wp_rewrite;
	
	$post_type_name = 'product'; // specify your own here
	$post_type_slug = 'product'; // here
	$taxonomy_name = 'platform'; // and here
	
	if( false === strpos( $_SERVER[ 'REQUEST_URI' ], $post_type_slug ) ) { // do not redirect if the URL doesn't contain the given post type slug
		return;
	}

	if( is_singular( $post_type_name ) ) { // if post type page
		$terms = wp_get_object_terms( $post->ID, $taxonomy_name ); // get terms attached
		
		if( ! is_wp_error( $terms ) && $terms ) {
			wp_safe_redirect( site_url( "/{$wp_rewrite->front}/{$terms[0]->slug}/{$post->post_name}" ), 301 );
			// wp_safe_redirect( get_permalink( $post->ID ), 301 ); // depends on the previous code from this post
			exit;
  		}
	}

}