query.h

#ifndef QUERY_H
#define QUERY_H

#include <iostream>
#include <string>
#include <memory>
#include "query_base.h"
#include "queryresult.h"
#include "textquery.h"
#include "wordquery.h"



/**
* @brief interface class to manage the Query_base inheritance hierachy
*/
class Query
{
	friend Query operator~(const Query&);
	friend Query operator|(const Query&, const Query&);
	friend Query operator&(const Query&, const Query&);
public:
	// build a new WordQuery
	Query(const std::string& s) : q(new WordQuery(s))
	{
		std::cout << "Query::Query(const std::string& s) where s=" + s + "\n";
	}

	// interface functions: call the corresponding Query_base operatopns
	QueryResult eval(const TextQuery& t) const
	{
		return q->eval(t);
	}
	std::string rep() const
	{
		std::cout << "Query::rep() \n";
		return q->rep();
	}

private:
	// constructor only for friends
	Query(std::shared_ptr<Query_base> query) :
		q(query)
	{
		std::cout << "Query::Query(std::shared_ptr<Query_base> query)\n";
	}
	std::shared_ptr<Query_base> q;
};

inline std::ostream&
operator << (std::ostream& os, const Query& query)
{
	// make a virtual call through its Query_base pointer to rep();
	return os << query.rep();
}

#endif // QUERY_H