package vsa;

import java.sql.*;

public class VSA {



    public static double cenaKnihy(String meno) throws ClassNotFoundException, SQLException {

        Class.forName("org.apache.derby.jdbc.ClientDriver");
        Connection con = DriverManager.getConnection("jdbc:derby://localhost:1527/sample", "app", "app");
        Statement st = con.createStatement();

        ResultSet rs = st.executeQuery("SELECT * FROM APP.KNIHA WHERE KNIHA.NAZOV = '" + meno + "'" );
        while(rs.next()) {
            return rs.getDouble(3);
        }
        System.out.println("Knihu nemame");
        return 0;
    }

    public static boolean pridajKnihu(String meno, Double cena) throws ClassNotFoundException, SQLException {

        Class.forName("org.apache.derby.jdbc.ClientDriver");
        Connection con = DriverManager.getConnection("jdbc:derby://localhost:1527/sample", "app", "app");
        Statement st = con.createStatement();

        ResultSet rs = st.executeQuery("SELECT * FROM APP.KNIHA WHERE KNIHA.NAZOV = '" + meno + "'" );
        if(!rs.next()){
            st.executeUpdate("INSERT INTO APP.KNIHA (NAZOV,CENA) VALUES ('" + meno + "'," + cena+")");
            return true;
        }
        return false;
    }

    public static void zlava(String meno) throws ClassNotFoundException, SQLException {

        Class.forName("org.apache.derby.jdbc.ClientDriver");
        Connection con = DriverManager.getConnection("jdbc:derby://localhost:1527/sample", "app", "app");
        Statement st = con.createStatement();

        st.executeUpdate("UPDATE APP.KNIHA SET CENA = CENA*0.8 WHERE NAZOV = '" + meno + "'");

    }

    public static void main(String[] args) throws ClassNotFoundException, SQLException {

        System.out.println(cenaKnihy("test"));
        pridajKnihu("novakniha",99.0);
        zlava("test");


    }


}