import java.security.SecureRandom;
import java.sql.*;
import java.util.Random;
import java.util.Scanner;

public class Main {
    static final String JDBC_DRIVER = "org.h2.Driver";
    static final String DB_URL = "jdbc:h2:~/test";

    // Database credentials
    static final String USER = "sa";
    static final String PASS = "";

    public static Random r =
            new Random(System.currentTimeMillis());

    public static void main(String[] args) {
        System.out.println("Hello, friend.");

        Connection conn = null;
        Statement stmt = null;

        try {
            Class.forName(JDBC_DRIVER);

            System.out.println("Connecting to database...");
            conn = DriverManager.getConnection(DB_URL, USER, PASS);

            stmt = conn.createStatement();

            int id = 0;

            while(true) {
                Scanner scanner = new Scanner(System.in);
                String cmd = scanner.next();

                if(cmd.equals("stop")) {
                    break;
                }

                switch(cmd) {
                    case "show":
                        showResults(stmt);
                        break;
                    case "insert":
                        insert(scanner, conn);
                        break;
                    default:
                        break;
                }

            }

            conn.close();
            stmt.close();
        } catch(Exception e) {
            e.printStackTrace();
        }
    }
    private static void insert(Scanner scanner, Connection conn) {
        try {
            PreparedStatement s = conn.prepareStatement(
                    "INSERT INTO PRODUCT VALUES(?, ?, ?, ?, ?)"
            );
            s.setInt(1, r.nextInt());

            System.out.println("Name:");
            String name = scanner.next();
            s.setString(2, name);

            s.setString(3, "NEW");

            System.out.println("Quantity:");
            String quant = scanner.next();
            s.setInt(4, Integer.parseInt(quant));

            System.out.println("Price:");
            String price = scanner.next();
            s.setInt(5, Integer.parseInt(price));

            s.execute();
            System.out.println("Inserted! Type show.");
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
    private static void delete(Scanner scanner, Connection conn) {
        try {
            PreparedStatement s = conn.prepareStatement(
                    "DELETE FROM PRODUCT WHERE NAME = ?"
            );
            System.out.println("Name = ");
            String name = scanner.next();
            s.setString(1, name);

            System.out.println("Inserted! Type show.");
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
    private static void showResults(Statement stm) {
        try {
            ResultSet set = stm.executeQuery("SELECT * FROM PRODUCT");
            while(set.next()) {
                System.out.println(
                        set.getString("ID") + " " +
                        set.getString("STATUS") + " " +
                        set.getString("NAME") + " " +
                        set.getString("QUANTITY") + " " +
                        set.getString("PRICE")
                );
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
}