#include <iostream>
#include <sstream>
#include <string>
#include <pqxx/pqxx>
#include "lab10.h" 

using namespace std;
using namespace pqxx;

int main(int argc, char* argv[]) {

	stringstream ss;
	ss << "dbname = " << labdbname << " user = " << labdbuser << " password = " << labdbpass \
		<< " host = " << labdbhost << " port = " << labdbport; 
	string s = ss.str();

	try {
		connection connlab(s);
		if (connlab.is_open()) {
         
			work trsxn{connlab};

			std::string selectStatement = "SELECT id_uczestnik, imie, nazwisko FROM uczestnik";

			stateless_cursor<pqxx::cursor_base::read_only, pqxx::cursor_base::owned> 
			uczestnik_cursor(trsxn, selectStatement, "uczestnikCursor", false);

			size_t idx = 0;   // start from 0
			size_t step = 3;  // ilosc rekordow w porcji 
			result res;
			do{
				// fetch next cursor
				res = uczestnik_cursor.retrieve( idx, idx + step );
				idx += step;

				size_t records = res.size();

				for( pqxx::result::const_iterator row : res ){
					cout << row["nazwisko"].as<std::string>()<< '\t' << row["imie"].as<std::string>()
						<< '\t' << row["id_uczestnik"].as<int>() << endl;
				}
			} while( res.size() == step ); //jezeli the res.size() != step to jest to ostatnia petla
			cout << " Sukces - wykonano" << endl;
			
			// dla polecenia select niekoniecznie
			trsxn.commit();
	
		} else {
			cout << "Problem z connection " << endl;
			return 3;
		}
		connlab.disconnect ();
	} catch (pqxx::sql_error const &e) {
		cerr << "SQL error: " << e.what() << std::endl;
		cerr << "Polecenie SQL: " << e.query() << std::endl;
		return 2;
	} catch (const std::exception &e) {
		cerr << e.what() << std::endl;
		return 1;
	}
}