#ifndef TPARSER_INCLUDED
#define TPARSER_INCLUDED

#include <memory>

#include "tcommon.h"
#include "tgrammar.h"

#undef DVAPI
#undef DVVAR
#ifdef TNZBASE_EXPORTS
#define DVAPI DV_EXPORT_API
#define DVVAR DV_EXPORT_VAR
#else
#define DVAPI DV_IMPORT_API
#define DVVAR DV_IMPORT_VAR
#endif

namespace TSyntax
{

struct DVAPI SyntaxToken {
	int m_pos, m_length;
	TokenType m_type;
};

class DVAPI Parser
{
	class Imp;
	std::unique_ptr<Imp> m_imp;

public:
	Parser(const Grammar *grammar);
	~Parser();

	//! parse the input string and create the corresponding calculator
	//! (returns 0 if the text contains mistakes)
	Calculator *parse(std::string text);

	//! return true if the last parsed string was correct
	bool isValid() const;

	//! return the last parsed string
	std::string getText() const;

	//! return the last error code (if the last parsed string was correct then returns "")
	std::string getError() const;

	//! if getError() != "" returns the position of the last parsed token
	//! the pair contains the indices of the first and the last characters of the token
	std::pair<int, int> getErrorPos() const;

	enum SyntaxStatus {
		Correct,
		Incomplete,
		Error,
		ExtraIgnored
	};
	SyntaxStatus checkSyntax(std::vector<SyntaxToken> &tokens, std::string text);

	void getSuggestions(Grammar::Suggestions &suggestions, std::string text);
	std::string getCurrentPatternString(std::string text);

private:
	// not implemented
	Parser(const Parser &);
	Parser &operator=(const Parser &);
};

} // namespace TSyntax

#endif