protected function apply_coupon_fixed_cart( $coupon, $items_to_apply, $amount = null ) {
		$total_discount = 0;
		$amount         = $amount ? $amount : wc_add_number_precision( $coupon->get_amount() );
		$items_to_apply = array_filter( $items_to_apply, array( $this, 'filter_products_with_price' ) );
		$item_count     = array_sum( wp_list_pluck( $items_to_apply, 'quantity' ) );

		if ( ! $item_count ) {
			return $total_discount;
		}

		if ( ! $amount ) {
			// If there is no amount we still send it through so filters are fired.
			$total_discount = $this->apply_coupon_fixed_product( $coupon, $items_to_apply, 0 );
		} else {
			$per_item_discount = absint( $amount / $item_count ); // round it down to the nearest cent.

			if ( $per_item_discount > 0 ) {
				$total_discount = $this->apply_coupon_fixed_product( $coupon, $items_to_apply, $per_item_discount );

				/**
				 * If there is still discount remaining, repeat the process.
				 */
				if ( $total_discount > 0 && $total_discount < $amount ) {
					$total_discount += $this->apply_coupon_fixed_cart( $coupon, $items_to_apply, $amount - $total_discount );
				}
			} elseif ( $amount > 0 ) {
				$total_discount += $this->apply_coupon_remainder( $coupon, $items_to_apply, $amount );
			}
		}
		return $total_discount;
	}