protected function apply_coupon_remainder( $coupon, $items_to_apply, $amount ) {
		$total_discount = 0;

		foreach ( $items_to_apply as $item ) {
			for ( $i = 0; $i < $item->quantity; $i ++ ) {
				// Find out how much price is available to discount for the item.
				$price_to_discount = $this->get_discounted_price_in_cents( $item );

				// Run coupon calculations.
				$discount = min( $price_to_discount, 1 );

				// Store totals.
				$total_discount += $discount;

				// Store code and discount amount per item.
				$this->discounts[ $coupon->get_code() ][ $item->key ] += $discount;

				if ( $total_discount >= $amount ) {
					break 2;
				}
			}
			if ( $total_discount >= $amount ) {
				break;
			}
		}
		return $total_discount;
	}