/*
 * Name: Phat Tu
 * Date: 04/28/17
 * Course Number: CSC-112-D01
 * Course Name: Intermediate Java
 * Problem Number: HW #10
 * Email: pgtu0001@student.stcc.edu
 * Create a server-client that calculates the quadratic formula.
 */

import java.net.*;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.io.*;
import java.util.Date;
import java.util.Scanner;

public class QuadraticServer implements Runnable {
    private int portNum;

    public QuadraticServer(int port) {
        this.portNum = port;
    }

    public class ThreadConnect extends Thread {
        private Socket connection;

        ThreadConnect(Socket x) {
            connection = x;
        }

        public void run() {
            PrintWriter pw = null;
            Scanner sc = null;
            try {
                pw = new PrintWriter(connection.getOutputStream());
                sc = new Scanner(connection.getInputStream());
                double a, b, c, discriminant, root1, root2;
                try {
                    a = Double.parseDouble(sc.nextLine());
                    b = Double.parseDouble(sc.nextLine());
                    c = Double.parseDouble(sc.nextLine());
                    discriminant = b * b - 4 * a * c;
                    root1 = ((-1 * b) + Math.sqrt(discriminant)) / (2 * a);
                    root2 = ((-1 * b) - Math.sqrt(discriminant)) / (2 * a);
                    pw.println(status(discriminant));
                    switch (status(discriminant)) {
                    case 0:
                        break;
                    case 1:
                        pw.println(root1);
                        break;
                    case 2: {
                        pw.println(root1);
                        pw.println(root2);
                    }
                        break;
                    default:
                        throw new RuntimeException("Operation has failed.");
                    }
                    pw.flush();
                } catch (Exception e) {
                }
            } catch (Exception e) {
            } finally {
                try {
                    sc.close();
                } catch (Exception e) {
                }
                try {
                    pw.close();
                } catch (Exception e) {
                }
                try {
                    connection.close();
                } catch (Exception e) {
                }
            }
        }

        private int status(double discriminant) {
            if (discriminant < 0)
                return 0;
            else if (discriminant == 0)
                return 1;
            else if (discriminant > 0)
                return 2;
            return -1;
        }
    }

    @Override
    public void run() {
        ServerSocket server;

        try {
            server = new ServerSocket(this.portNum);
            while (true) {
                message("Waiting for connection.");
                Socket connection = server.accept();
                logging(connection);
                new Thread(new ThreadConnect(connection)).start();
                message("Done.\n");
            }
        } catch (Exception e) {
            e.printStackTrace();
        }

    }

    private void logging(Socket connection) {
        message("");
        message("Communicating with " + connection.getInetAddress() + " " + connection.getPort());
        DateFormat dateFormat = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");
        Date date = new Date();
        message("Time: " + dateFormat.format(date));
    }

    private static void message(String string) {
        System.out.println(string);
    }

    public static void main(String[] args) {
        QuadraticServer q = new QuadraticServer(5012);
        new Thread(q).start();
    }

}