package com.company;

import java.io.*;
import java.net.InetAddress;
import java.net.Socket;
import java.net.UnknownHostException;
import java.util.ArrayList;
import java.util.Base64;
import java.util.Random;
import java.util.Scanner;

/**
 * Created by lamec on 12/7/2016.
 */
public class Client {
    private static Socket socket;
    private static String machineName;
    private static int portNumber;
    public static BufferedReader inputStream;
    public static PrintStream outputStream;
    public static String hostname;
    private static String username;
    private static ArrayList<String> activeUsers;
    private static ArrayList<String> allUsers;
    private static boolean isOperator = false;

    public static void main(String[] args){
        Integer integer = new Integer(args[0]);
        try {
            Scanner sc = new Scanner(System.in);
            portNumber = integer;
            hostname = InetAddress.getLocalHost().getHostName();
            socket = new Socket(hostname, portNumber);
            inputStream = new BufferedReader(new InputStreamReader(socket.getInputStream()));
            outputStream = new PrintStream(socket.getOutputStream());
            String serverResponse;
            String userInput;
            updateActiveUsers();

            activeUsers.add(username = authenticationClient());

            FileOutputStream fileOutputStream = new FileOutputStream("active.txt");
            ObjectOutputStream objectOutputStream = new ObjectOutputStream(fileOutputStream);
            objectOutputStream.writeObject(activeUsers);
            fileOutputStream.close();
            objectOutputStream.close();
            allUsers = (ArrayList<String>)readObjectFromServer();
            while(true){
                MailList currentMailList = (MailList)readObjectFromServer();
                boolean newMailCheck = false;
                for(int i = 0; i < currentMailList.getMailList().size(); i++){
                    if(currentMailList.getMailList().get(i).isRead() == false && currentMailList.getMailList().get(i).getTo().equals(username))
                        newMailCheck = true;
                }
                if(isOperator){
                    String[] aux = (String[])readObjectFromServer();
                    if(aux.length > 1 && allUsers.contains(aux[1])){
                        System.out.println(aux[1] + " wants to access server. Allow? (Y/N):");
                        userInput = sc.nextLine();
                        outputStream.println(userInput);
                    }
                }
                if(newMailCheck)
                    System.out.println("You have unread messages!");
                System.out.println("\nWelcome " + username + ".\n" +
                        "Please select an action:\n" +
                        "1)List all messages.\n" +
                        "2)List all users.\n" +
                        "3)Send message.\n" +
                        "4)List read.\n" +
                        "5)Delete Messages.\n" +
                        "6)Change Password.\n" +
                        "7)Log in as operator.\n" +
                        "8)Exit."
                );
                if(isOperator){
                    System.out.println("9)Change server databases.");
                }
                userInput = sc.nextLine();
                outputStream.println(userInput);
                if(userInput.equals("1")){
                    MailList userMailList = (MailList)readObjectFromServer();
                    for(int i = 0; i < userMailList.getMailList().size(); i++){
                        if(!userMailList.getMailList().get(i).isRead()){
                            System.out.println("\nFrom: " + userMailList.getMailList().get(i).getFrom() + " Subject: " + userMailList.getMailList().get(i).getSubject());
                            System.out.println(userMailList.getMailList().get(i).getMessage());
                            userMailList.getMailList().get(i).setRead(true);
                        }
                    }
                    writeObjectToServer(userMailList);
                }
                else if(userInput.equals("2")){
                    for(int i = 0; i < activeUsers.size(); i++){
                        System.out.println(activeUsers.get(i).toString());
                    }
                }
                else if(userInput.equals("3")){
                    sendMessage();
                }
                else if(userInput.equals("4")){
                    MailList userMailList = (MailList)readObjectFromServer();
                    for(int i = 0; i < userMailList.getMailList().size(); i++){
                        if(userMailList.getMailList().get(i).isRead()){
                            System.out.println("\nFrom: " + userMailList.getMailList().get(i).getFrom() + " Subject: " + userMailList.getMailList().get(i).getSubject());
                            System.out.println(userMailList.getMailList().get(i).getMessage());
                        }
                    }
                    writeObjectToServer(userMailList);
                }
                else if(userInput.equals("5")){
                    MailList userMailList = (MailList)readObjectFromServer();
                    for(int i = 0; i < userMailList.getMailList().size(); i++){
                        if(userMailList.getMailList().get(i).isRead()){
                            System.out.println("\n" + (i + 1) + "From: " + userMailList.getMailList().get(i).getFrom() + " Subject: " + userMailList.getMailList().get(i).getSubject());
                        }
                    }
                    System.out.println("Enter the number of the messages you want to delete (separate with , and no spaces):");
                    userInput = sc.nextLine();
                    String[] messagesToDelete = userInput.split(",");

                    for(int i = 0; i < messagesToDelete.length; i++){
                        int l = Integer.valueOf(messagesToDelete[i]);
                        userMailList.getMailList().remove(l - 1 - i);
                    }
                    writeObjectToServer(userMailList);
                }
                else if(userInput.equals("6")){
                    boolean flag = true;
                    while(flag){
                        System.out.println("Insert your desired new password:");
                        userInput = sc.nextLine();
                        if(userInput.length() > 9){
                            System.out.println("Password too long, try again.");
                        }
                        else {
                            flag = false;
                        }
                    }
                    outputStream.println(userInput);
                }
                else if(userInput.equals("7")){
                    String operatorPermission = inputStream.readLine();
                    if (operatorPermission.equals("true")){
                        isOperator = true;
                        System.out.println("Operator permission granted.");
                    }
                    else{
                        System.out.println("There is already a server operator.");
                    }
                }
                else if(userInput.equals("9") && isOperator){
                    while(!userInput.equals("3")){
                        String[][] credentials = (String[][])readObjectFromServer();
                        ArrayList<ArrayList<String>> mutableCredentials = new ArrayList<ArrayList<String>>();
                        mutableCredentials.add(0, new ArrayList<String>());
                        mutableCredentials.add(1, new ArrayList<String>());
                        for(int i = 0; i < credentials[0].length; i++){
                            mutableCredentials.get(0).add(credentials[0][i]);
                            mutableCredentials.get(1).add(credentials[1][i]);
                            System.out.println((i + 1) + ")\n" +
                                    "Username:" + mutableCredentials.get(0).get(i) + "\n" +
                                    "Password:" + mutableCredentials.get(1).get(i));
                        }
                        System.out.println("Press 1 to add, 2 to remove user and 3 to go back:");
                        userInput = sc.nextLine();
                        if(userInput.equals("1")){
                            System.out.println("Insert desired username:");
                            String tempUser = sc.nextLine();
                            System.out.println("Insert desired password:");
                            String tempPassword = sc.nextLine();
                            mutableCredentials.get(0).add(tempUser);
                            mutableCredentials.get(1).add(tempPassword);
                        }
                        else if(userInput.equals("2")){
                            System.out.println("Which user do you want to remove?");
                            String aux = sc.nextLine();
                            int o = Integer.valueOf(aux) - 1;
                            mutableCredentials.get(0).remove(o);
                            mutableCredentials.get(1).remove(o);
                        }
                        writeObjectToServer(mutableCredentials);
                        if(userInput.equals("3")){
                            outputStream.println("false");
                        }
                        else{
                            outputStream.println("true");
                        }
                    }
                }
                else{
                    sc.close();
                    closeClient();
                }
            }
        } catch (UnknownHostException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        }
    }

    private static void updateActiveUsers() throws IOException, ClassNotFoundException {
        //Idealmente o cliente não precisaria de acesso ao ficheiro com os utilizadores ativos, mas como ele tem acesso a essa informação de qualquer maneira colocamos aqui para simplificar o código já complicado de autenticação
        BufferedReader bufferedReader = new BufferedReader(new FileReader("active.txt"));
        if(bufferedReader.readLine() != null){ //Check if file is empty
            bufferedReader.close();
            FileInputStream fileInputStream = new FileInputStream("active.txt");
            ObjectInputStream objectInputStream = new ObjectInputStream(fileInputStream);
            activeUsers = (ArrayList<String>)objectInputStream.readObject();
            fileInputStream.close();
            objectInputStream.close();
        }
        else {
            bufferedReader.close();
            activeUsers = new ArrayList<String>();
        }
    }
    private static void sendMessage(){
        String userInput;
        Scanner sc = new Scanner(System.in);
        boolean validTo = true;
        String[] to = new String[0];
        while(validTo) {
            validTo = false;
            System.out.println("Please insert all clients you want to send your message to (separated by , with no spaces):");
            userInput = sc.nextLine();
            to = userInput.split(",");
            for (String aTo : to) {
                boolean foundName = false;
                for (int j = 0; j < allUsers.size(); j++) {
                    if (aTo.equals(allUsers.get(j))) {
                        foundName = true;
                    }
                }
                if (!foundName) {
                    validTo = true;
                }
            }
            if(validTo) {
                System.out.println("You entered one or more invalid users.");
            }
        }
        System.out.println("Subject (enter to finish):");
        String subject = sc.nextLine();
        System.out.println("Message (enter to finish):");
        String message = sc.nextLine();
        Mail mail = new Mail(to,username,subject,false,message);
        writeObjectToServer(mail);
    }
    private static Object readObjectFromServer(){
        String aux = null;
        Object o = new Object();
        try {
            aux = inputStream.readLine();
            byte [] data = Base64.getDecoder().decode(aux);
            ObjectInputStream ois = new ObjectInputStream(new ByteArrayInputStream(data));
            o  = ois.readObject();
            ois.close();
        } catch (IOException e) {
            e.printStackTrace();
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        }
        return o;
    }
    private static void writeObjectToServer(Object o){
        try{
            ByteArrayOutputStream baos = new ByteArrayOutputStream();
            ObjectOutputStream oos = new ObjectOutputStream( baos );
            oos.writeObject(o);
            oos.close();
            String string = Base64.getEncoder().encodeToString(baos.toByteArray());
            outputStream.println(string);}
        catch (IOException e) {
            e.printStackTrace();
        }
    }
    private static String authenticationClient(){
        try{
            Scanner sc = new Scanner(System.in);
            System.out.println(inputStream.readLine());
            boolean aux = true;
            String username = null;
            while(aux){
                aux = false;
                username = sc.nextLine();
                for (int i = 0; i < activeUsers.size(); i++) {
                    if (username.equals(activeUsers.get(i))) {
                        System.out.println("That user is already active, try again.");
                        aux = true;
                    }
                }

            }
            outputStream.println(username);
            if(inputStream.readLine().equals("false")){
                System.out.println("Unauthorized username, disconnecting...");
                closeClient();
                return null;
            }
            while(true){
                System.out.println(inputStream.readLine());
                String password = sc.nextLine();
                outputStream.println(password);
                String receiver = inputStream.readLine();
                if(receiver.equals("true")) break;
                else{
                    System.out.println(receiver);
                    String string = sc.nextLine();
                    outputStream.println(string);
                    if(!string.equals("Y")){
                        closeClient();
                        return null;
                    }
                }
            }
            String operatorCheck = inputStream.readLine();
            if(operatorCheck.equals("true")){
                System.out.println("Waiting for operator permission...");
                String operationPermission = inputStream.readLine();
                if(operationPermission.equals("false")){
                    System.out.println("Permission denied. Closing client.");
                    closeClient();
                }
            }
            return username;
        } catch (IOException e) {
            e.printStackTrace();
        }
        return null;
    }
    private static void closeClient(){
        try {
            FileInputStream fileInputStream = new FileInputStream("active.txt");
            ObjectInputStream objectInputStream = new ObjectInputStream(fileInputStream);

            activeUsers = (ArrayList<String>)objectInputStream.readObject();
            activeUsers.remove(username);

            FileOutputStream fileOutputStream = new FileOutputStream("active.txt");
            ObjectOutputStream objectOutputStream = new ObjectOutputStream(fileOutputStream);

            objectOutputStream.writeObject(activeUsers);

            outputStream.close();
            inputStream.close();
            socket.close();

        } catch (IOException e) {
            e.printStackTrace();
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        }
        System.exit(0);
    }
}