Woo-commerce functionality with variation products
/* Set woo-commerce session */
WC()->session->set( ‘gift_user’, “data” );

/* Get woo-commerce session */
WC()->session->get( ‘gift_user’);

/* Store variation using variation ID */
$variation = array(‘attribute_variation’ => $color);

/* Empty Woo-Commerce cart */
WC()->cart->empty_cart();

/*Get Woo-commerce price*/
$_product = wc_get_product( $product_id );

$_product->get_regular_price();
$_product->get_sale_price();
$_product->get_price();