Query.h

#ifndef QUERY_H
#define QUERY_H

#include <iostream>
#include <fstream>
#include <sstream>
#include <string>
#include <set>
#include <memory>
#include <regex>
#include "TextQuery.h"
#include "QueryResult.h"

class QueryBase {
  public:
    using line_no = TextQuery::line_no;
	virtual ~QueryBase() = default;
    virtual QueryResult eval(const TextQuery&) const = 0; 
    virtual std::string rep() const = 0;
	static std::shared_ptr<QueryBase> factory(const std::string& s);
};

class WordQuery: public QueryBase {
  public:
    WordQuery(const std::string &s): query_word(s) { }
    QueryResult eval(const TextQuery &t) const
                    { return t.query(query_word); }
	std::string rep() const { return query_word; }
  private:
    std::string query_word;
};

class NotQuery : public QueryBase
{
  public:
    NotQuery(const std::string &s) : query_word(s) {}
    QueryResult eval(const TextQuery&) const;
    std::string rep() const { return "NOT " + query_word; }
  private:	
    std::string query_word;
};
   
class AndQuery: public QueryBase {
  public:
    AndQuery(const std::string &left_string, const std::string &right_string):
      left_query(left_string), right_query(right_string) {}
    QueryResult eval(const TextQuery&) const;
	std::string rep() const { return left_query + " AND " + right_query; }
  protected:	
	std::string left_query, right_query;
};

class OrQuery: public QueryBase {
  public:
    OrQuery(const std::string &left_string, const std::string &right_string):
      left_query(left_string), right_query(right_string) {}
    QueryResult eval(const TextQuery&) const;
	std::string rep() const { return left_query + " OR " + right_query; }
  private:
	std::string left_query, right_query;
};

class NQuery : public AndQuery {
  public:
    NQuery(const std::string &left_string, const std::string &right_string, int distance):
      AndQuery(left_string, right_string), dist(distance) {}
    QueryResult eval(const TextQuery&) const;
	std::string rep() const { return left_query + " " + std::to_string(dist) + " " + right_query; }
  private:
    int dist;
};
#endif