#ifndef NEWSBOAT_FILTER_PARSER_H_
#define NEWSBOAT_FILTER_PARSER_H_

#include <string>
#include <sys/types.h>
#include <regex.h>


enum { LOGOP_INVALID = 0, LOGOP_AND = 1, LOGOP_OR, MATCHOP_EQ, MATCHOP_NE, MATCHOP_RXEQ, MATCHOP_RXNE, MATCHOP_LT, MATCHOP_GT, MATCHOP_LE, MATCHOP_GE, MATCHOP_CONTAINS, MATCHOP_CONTAINSNOT, MATCHOP_BETWEEN };

struct expression {
	expression(const std::string& n, const std::string& lit, int o);
	expression(int o = LOGOP_INVALID);
	~expression();

	std::string name;
	std::string literal;
	int op;
	expression * l, * r;
	expression * parent;
	regex_t * regex;
};

class FilterParser {
	public:
		FilterParser();
		FilterParser(const FilterParser& p);
		~FilterParser();
		void add_logop(int op);
		void add_matchexpr(char * name, int op, char * lit);
		void open_block();
		void close_block();

		bool parse_string(const std::string& str);
		void cleanup();

		inline expression * get_root() { return root; }
		FilterParser& operator=(FilterParser& p);

		const std::wstring& get_error() { return errmsg; }

	private:
		void print_tree_r(expression * e, unsigned int depth);
		void cleanup_r(expression * e);

		expression * root;
		expression * curpos;
		bool next_must_descend_right;
		std::string strexpr;
		std::wstring errmsg;
};


#endif /* NEWSBOAT_FILTER_PARSER_H_ */