import java.io.*;
import java.net.*;
import java.lang.*;
import java.util.*;
import java.util.HashMap;

public class karlServer {
    private final int port = 8989;
    private ServerSocket serverSocket = null;
    public static HashMap<String, int[]> sessionMap = new HashMap<String, int[]>();
    public static String clue = "Guess a number between 1 and 100";
    public static String history = "You have guessed 0 times";


    public static void main(String[] args) {
        new karlServer();
    }

    public karlServer() {
        try (ServerSocket serverSocket = new ServerSocket(this.port)) {
            System.out.println("Listening on port: " + this.port);

            String requestType = "";
            StringBuilder postRequest = new StringBuilder();
            int guess = 999999;
            String cookie="0";
            Boolean startGame = false;

            while (true) { // While listening

                try (Socket socket = serverSocket.accept();
                     BufferedReader in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
                     PrintWriter printWriteOut = new PrintWriter(socket.getOutputStream(), true)) {

                    System.err.println("Connected on " + this.port);


                    String line;
                    String tempLine = "Not yet initialized";
                    String[] htmlResponse = readHtmlFile("guess.html"); // Read html-file that we will update based on what client send.

                    while ((line = in.readLine()) != null) { // read
                        tempLine = line;
                        System.out.println(" <<< " + line); // log


                        if (line.matches("GET\\s+.*")) {
                            // process the GET request
                            System.err.println("Vi har en GET request");
                            requestType = "GET";

                            cookie = GETreader(in, printWriteOut, cookie);
                        }

                        if (line.matches("POST\\s+.*")) {
                            // process the POST request
                            System.err.println("Vi har en POST request");
                            requestType = "POST";

                            String[] postResult = POSTreader(in, printWriteOut, cookie); // Kanske kan ta bort cookie här
                            cookie = postResult[1];
                            String guessString = postResult[0];
                            // Convert the guess to an integer
                            try{
                              guess = Integer.parseInt(guessString);
                            } catch (NumberFormatException e){
                              System.out.println("The guess was not a number.");
                            }

                        }
                        break;
                    }

                    // The Game
                    System.err.println("Check if first letter in cookie = S");
                    System.err.println("Cookie: " + cookie);
                    if (cookie.charAt(0) == 'S') {
                      startGame = true;
                      clue = "Guess a number between 1 and 100";
                      history = "You have guessed 0 times";
                      System.err.println("First letter did equal S and we set startGame = true;");
                    } else {
                      startGame = false;
                    }

                    if (startGame != true) {
                      System.err.println("Eftersom det inte var startGame så hämtar vi info på denna cookie: " + cookie);
                      int[] client = sessionMap.get(cookie);  // [0] = Correct Answer
                                                              // [1] = Number of Guesses
                                                              // [2] = Min Guess
                                                              // [3] = Max Guess
                      System.err.println("Vi försöker plocka ut info med denna cookie: " + cookie);

                      history = "You have guessed " + String.valueOf(client[1]) + " times";
                      if (guess != client[0]){
                        if (guess< 1 || guess > 100) {
                          requestType = "Your guess was out of bounds, you have to guess a number higher than 1 and lower than 100";
                          history = requestType;
                        }
                        if (guess< client[2] || guess > client[3]) {
                          requestType = "The guess was smaller current min or larger than current max";
                          // No update needed
                        }
                        if (requestType == "POST") {
                          if (guess > client[0] && guess != 999999){ // Less than current max guess
                            client[3] = guess;
                          }
                          if (guess < client[0]){
                            client[2] = guess;
                          }
                        }
                        clue = "Guess a number between " + String.valueOf(client[2]) + " and " + String.valueOf(client[3]);
                        sessionMap.replace(cookie, client); // Kanske även ska store counter
                      } else {
                        // You won!
                        // Fixa svaren för det
                        clue = "Happy boy! You have guessed have guessed the correct number: " + String.valueOf(client[0]);
                        history = "It only took you " + String.valueOf(client[1]) + " guesses!";
                        sessionMap.remove(cookie);
                      }
                      // For me to see where it's at
                      System.err.println("------------------------------");
                      System.err.println("We had a guess and updated the Session");
                      System.err.println("Correct answer gameInfo[0] = " + String.valueOf(client[0]));
                      System.err.println("Min Guess = " + String.valueOf(client[2]));
                      System.err.println("Max Guess = " + String.valueOf(client[3]));
                      System.err.println("Stored on the Cookie:  = " + cookie);
                      System.err.println("------------------------------");
                    }

                    System.out.println(" >>> " + "HTTP RESPONSE"); // log

                    // update html
                    htmlResponse[7] = htmlResponse[7].replace("{clue}", clue);
                    htmlResponse[9] = htmlResponse[9].replace("{history}", history);

                    // Sending response to client
                    printWriteOut.println("HTTP/1.1 200 OK"); // Initial line
                    printWriteOut.println("Content-Type: text/html"); // Specifies content in message
                    System.err.println(" >>> " + "HTTP/1.1 200 OK");
                    System.err.println(" >>> " + "Content-Type: text/html");
                    if (startGame) {
                      printWriteOut.println(cookie);
                    }
                    printWriteOut.println("\n"); // new line
                    for (int row=0; row<htmlResponse.length; row++) {
                      System.err.println(" >>> " + htmlResponse[row]);
                      printWriteOut.println(htmlResponse[row]);
                    }

                    // Reset Variables for next request and response
                    startGame = false;
                    cookie = cookie.replace("Set-Cookie: JSESSIONID=", "");

                    // Close this request
                    printWriteOut.close();
                    System.err.println("We just closed");

                } catch (IOException e) {
                    System.err.println(e.getMessage());
                }

            }
        } catch (IOException e) {
            System.err.println(e.getMessage());
            System.err.println("Could not listen on port: " + this.port);
            System.exit(1);
        }
    }
    public String GETreader(BufferedReader in, PrintWriter out, String cookie) {
      Boolean startGame = true;
      String line;
      try {
        while(in.ready()) {
          line = in.readLine();
          System.out.println("In function <<< " + line);

          if(line.contains("Cookie:")==true){
            System.out.println("We had the line " + line);
            cookie = line.substring(line.length()-13, line.length()); // Retrieve the part of cookie line we use as key
            System.out.println("We got this Cookie in the GET request: " + cookie);
            startGame = false;
          }
        }
        } catch (IOException e) {
          e.printStackTrace();
        }

      System.err.println("Check if not in sessionMap, key: " + cookie);
      // if (cookie in HashMap) don't start a new game:
      if (!sessionMap.containsKey(cookie)){ startGame = true; System.err.println(cookie + " was not in sessionMap");}

      // else: new game
      if (startGame == true) {
        System.err.println("We have a GET request and should start new game");
        int correct = (int)(Math.random() * 100 + 1); // Correct Answer
        int[] gameInfo = { correct, 0, 1, 100};
        String timeStamp = Long.toString(System.currentTimeMillis());
        cookie = "Set-Cookie: JSESSIONID="+timeStamp;
        sessionMap.put(timeStamp, gameInfo); //cookie = timeStamp;

        System.err.println("------------------------------");
        System.err.println("We started a new game with the following information:");
        System.err.println("Correct answer gameInfo[0] = " + String.valueOf(gameInfo[0]));
        System.err.println("Min Guess = " + String.valueOf(gameInfo[2]));
        System.err.println("Max Guess = " + String.valueOf(gameInfo[3]));
        System.err.println("Stored on the Cookie:  = " + cookie);
        System.err.println("------------------------------");
        System.err.println("Put in sessionMap on key: " + timeStamp);

      }
      // Return the cookie that identifies the client who sent the GET request
      // So we can send the apropriate respnse for exactly this client
      return cookie;

    }
    public String[] POSTreader(BufferedReader in, PrintWriter out, String cookie) {
      String line = "";
      int guess = 0;
      try {
        while(in.ready()) {
          line = in.readLine();
          System.out.println("In function <<< " + line);
          if(line.contains("Cookie:")==true) {
            cookie = line.substring(line.length()-13, line.length());
          }
          if(line.equals("")){
            break;
          }
        }
        } catch (IOException e) {
          e.printStackTrace();
      }
      int[] client = sessionMap.get(cookie);  // [0] = Correct Answer
                                              // [1] = Number of Guesses
                                              // [2] = Min Guess
                                              // [3] = Max Guess
      client[1] += 1; // Add 1 number of guesses for each POST request
      sessionMap.replace(cookie, client); // Update number of guesses in hashMap
      StringBuilder postRequest = new StringBuilder();
      try {
        // For some reason my loop gets stuck if at the empty line everytime,
        // so I have to continue letter by letter from there
        while (in.ready()) {
          char letter = (char)in.read();
          System.out.println("In function <<< " + letter);
          postRequest.append(letter);
        }
      } catch (IOException e) {
        e.printStackTrace();
      }
      String guessString = postRequest.toString().replace("guess=", ""); // Remove all but the number
      System.out.println("\n");
      System.err.println("Vår gissning är: " + guessString);

      // Return the guess and the cookie that identifies the client who sent it
      String[] stringArray = new String[]{ guessString, cookie };
      return stringArray;
    }

    public static String[] readHtmlFile(String path) {
      // Read the html file that we use as base for all our responses
      String[] html = new String[16];
      String line;
      try {
        FileReader fr = new FileReader(path);
        BufferedReader br = new BufferedReader(fr);
        int row = 0;
        while ((line = br.readLine()) != null){
          html[row] = line;
          row += 1;
        }
        br.close();
      } catch (FileNotFoundException e) {
        System.out.println("Kan inte hitta file: " + path);
      } catch (IOException e) {
        // Kan inte läsa file
        e.printStackTrace();
      }
      return html;
    }

}