basket.h

#ifndef BASKET_H
#define BASKET_H

#include "quote.h"
#include <set>
#include <memory>


// a basket of objects from Quote hierachy, using smart pointers.
class Basket
{
public:
	// copy verison
	void add_item(const Quote& sale)
	{
		items.insert(std::shared_ptr<Quote>(sale.clone()));
	}
	// move version
	void add_item(Quote&& sale)
	{
		items.insert(std::shared_ptr<Quote>(std::move(sale).clone()));
	}

	double total_receipt(std::ostream& os) const;

private:

	// function to compare needed by the multiset member
	static bool compare(const std::shared_ptr<Quote>& lhs,
		const std::shared_ptr<Quote>& rhs)
	{
		return lhs->isbn() < rhs->isbn();
	}

	// hold multiple quotes, ordered by the compare member
	std::multiset<std::shared_ptr<Quote>, decltype(compare)*>
		items{ compare };
};

#endif // BASKET_H