VOCAB

import java.util.Scanner;
import java.util.ArrayList;

public class VocabBuilder
{
    //boolean value used as condition in runMenu() to quit the whole game if true (will not run the main menu anymore)
    private boolean quit;

    //holds the index value in the array for the current user logged in
    //it is initalised as -1, which means no user has logged in yet
    private int currentPlayer = -1;

    //initialises the ArrayList that will hold player information (the player objects)
    ArrayList<Player> playerList = new ArrayList<Player>();


    public static void main(String[] args){
        VocabBuilder menu = new VocabBuilder(); //constructs the Main Menu
        menu.runMenu(); //runs the main Menu
    }

    //This method is used to run the menu
    private void runMenu()
    {
        while (!quit)
        {
            //Only runs the menu if the user has not selected to quit
            printHeader();
            printMenu();
            char choice = getUserChoice();
            performMenu(choice);
        }
    }

    //This method is used to print the top of the main menu
    private void printHeader()
    {
        if (currentPlayer==-1)
        {
            System.out.println("    Welcome to the Word Game");
        }
        else
        {
            System.out.println("    Welcome to the Word Game " + playerList.get(currentPlayer).getName() + "!");
        }
    }

    //This method is used to print the content of the main menu
    private static void printMenu()
    {
        System.out.println("        Login (L)");
        System.out.println("        Register (R)");
        System.out.println("        About (A)");
        System.out.println("        Play the Game (P)");
        System.out.println("        Show the Leader Board (B)");
        System.out.println("        Quit (Q)");
        System.out.print("\n        Please choose an option: ");
    }

    //This method is used to validate and get the user's choice from the main menu
    private char getUserChoice()
    {
        Scanner scan = new Scanner(System.in);
        char selection = scan.next().charAt(0);
        char selectionUpper = Character.toUpperCase(selection);

        //checks for input error
        while ((selectionUpper!='L') && (selectionUpper!='R')&&(selectionUpper!='A') && (selectionUpper!='P')&&(selectionUpper!='B') && (selectionUpper!='Q'))
        {
            System.out.println("\n        You have entered an incorrect menu choice.");
            System.out.print("        Please enter one of the choices given: ");
            selection = scan.next().charAt(0);
            selectionUpper = Character.toUpperCase(selection);
        }

        return selectionUpper; //returns a correct menu choise as an upper case letter
    }

    private void performMenu(char choice)
    {
        switch (choice)
        {
            case 'L':
                Login();
                break;
            case 'R':
                Register();
                break;
            case 'A':
                printAbout();
                break;
            case 'P':
                Play();
                break;
            case 'B':
                quit = true;
                break;
            case 'Q':
                quit = true;
                break;
        }
    }

    private static void printAbout(){
        System.out.println("\n    Instructions on how to play the Word game:");
        System.out.println("    This game is a vocabulary builder, which aims to help you in learning the definition of certain words.");
        System.out.println("    Each time you play the game, a new word will appear, and you will have to select a synonym from a list");
        System.out.println("    of possible options. Only one word will be the correct answer each time. After selecting a word, the");
        System.out.println("    game will let you know whether you have chosen the correct synonym, and if not, will show the correct answer.");
        System.out.println("    Each game is comprised of 10 guessing stages, and during each stage you will be shown your current score.");
        System.out.println("    At the end of the game, you can compare your final score with those of other players in the leaderboard.");
        System.out.println();
    }

    //creates temporary variables to hold the player's information during registration
    private void Register()
    {
        String tempName, tempSurname, tempUsername, tempPassword;

        //each variable is assigned values by calling the methods responsible for getting the user's details
        tempName = setName();
        tempSurname = setSurname();
        tempUsername = setUsername();
        tempPassword = setPassword();

        System.out.println("\n    You have successfully registered a new player with username " + tempUsername);
        System.out.println("    You need to log in to play the game");

        //creates a new player object using the player's details
        Player newPlayer = new Player(tempName,tempSurname,tempUsername,tempPassword, 0, 0);

        //adds the new player's details to the array list
        playerList.add(newPlayer);
    }

    private String setName()
    {
        Scanner scan = new Scanner(System.in);
        System.out.print("\n    Enter your first name: ");
        String name = scan.nextLine();
        while (!nameValidation(name))
        {
            System.out.print("\n    Please enter your first name again: ");
            name = scan.nextLine();
        }
        return name;
    }

    private String setSurname()
    {
        Scanner scan = new Scanner(System.in);
        System.out.print("\n    Enter your last name: ");
        String surname = scan.nextLine();
        while (!nameValidation(surname))
        {
            System.out.print("\n    Please enter your last name again: ");
            surname = scan.nextLine();
        }
        return surname;
    }

    private boolean nameValidation(String valName)
    {
        boolean valid = true;
        String numbers = "(.*[0-9].*)";
        String specialChars = "(.*[,~,!,@,#,$,%,^,&,*,(,),-,_,=,+,[,{,],},|,;,:,<,>,/,?].*$)";

        if (valName.length() <2 )
        {
            System.out.print("\n    Your name must be at least 2 characters long.");
            valid = false;
        }

        if (valName.matches(numbers))
        {
            System.out.print("\n    Your name can not contain any numbers.");
            valid = false;
        }

        if (valName.matches(specialChars))
        {
            System.out.print("\n    Your name can not contain any special characters.");
            valid = false;
        }

        return valid;
    }

    private String setUsername()
    {
        Scanner scan = new Scanner(System.in);
        System.out.print("\n    Guidelines for choosing your username: ");
        System.out.print("\n    1) Your player username needs to be at least 3 characters long and no more than 12.");
        System.out.print("\n    2) The first character can not be a number.");
        System.out.print("\n    3) The username can not contain any special characters. ");
        System.out.print("\n    Enter your desired player username: ");
        String username = scan.nextLine();
        while (!usernameValidation(username))
        {
            System.out.print("\n    Please enter a new username: ");
            username = scan.nextLine();
        }
        return username.toLowerCase();
    }

    private boolean usernameValidation(String valUsername) {
        boolean valid = true;
        String numbers = "(.*[0-9].*)";
        String specialChars = "(.*[,~,!,@,#,$,%,^,&,*,(,),-,_,=,+,[,{,],},|,;,:,<,>,/,?].*$)";

        if ((valUsername.length() < 3) || (valUsername.length() > 12))
        {
            System.out.print("\n    Your username is too short or too long.");
            valid = false;
        }

        if ((valUsername.substring(0,1)).matches(numbers))
        {
            System.out.print("\n    Your username should not begin with a number.");
            valid = false;
        }

        if (valUsername.matches(specialChars))
        {
            System.out.print("\n    Your username should not contain any special characters.");
            valid = false;
        }

        for (int i=0; i < playerList.size(); i++)
        {
            if (valUsername.equalsIgnoreCase(playerList.get(i).getUsername()))
            {
                System.out.print("\n    This username is already in use.");
                valid = false;
                break; //usernames will be unique, so we know there won't be another one, so no need to continue the loop
            }
        }

        return valid;
}

    private String setPassword()
    {
        Scanner scan = new Scanner(System.in);
        System.out.print("\n    Guidelines for choosing your password: ");
        System.out.print("\n    1) Your password needs to be at least 8 characters long but no more than 15.");
        System.out.print("\n    2) Your password should contain at least one uppercase letter");
        System.out.print("\n    3) Your password should contain at least one special character. ");
        System.out.print("\n    Enter your desired player password: ");
        String password = scan.nextLine();
        while (!passwordValidation(password))
        {
            System.out.print("\n    Please enter a new password: ");
            password = scan.nextLine();
        }
        return password;
    }

    private boolean passwordValidation(String valPassword){
        boolean valid = true;
        String upperCase = "(.*[A-Z].*)";
        String specialChars = "(.*[,~,!,@,#,$,%,^,&,*,(,),-,_,=,+,[,{,],},|,;,:,<,>,/,?].*$)";

        if ((valPassword.length() < 8) || (valPassword.length() > 15))
        {
            System.out.print("\n    Your password is too short or too long.");
            valid = false;
        }

        if (!valPassword.matches(upperCase))
        {
            System.out.print("\n    Your password should contain at least one uppercase letter.");
            valid = false;
        }

        if (!valPassword.matches(specialChars))
        {
            System.out.print("\n    Your password should contain at least one special character.");
            System.out.print("\n    Tip: Some of the characters you can use are #,$,%,*,^,@, etc.");
            valid = false;
        }

        return valid;
    }

    private void Login()
    {
        int tempPlayer = -1;
        //user will only be allowed to login after they have registered
        //if the ArrayList is empty it means no player profiles (objects) have been created yet
        if (playerList.isEmpty())
        {
            System.out.println("\n    You need to be registered before you can login.");
            System.out.println("    Register by choosing R from the main menu.");
            System.out.println();
        }
        else
        {
            Scanner scan = new Scanner(System.in);
            System.out.println("\n    Enter your username: ");
            String verification = scan.nextLine();

            //loops through the array to check whether the username entered by the user (ignoring case)
            //is equal to any of the usernames in the player database
            for (int i=0; i < playerList.size(); i++)
            {
                if (verification.equalsIgnoreCase(playerList.get(i).getUsername()))
                {
                    tempPlayer = i;
                    break; //once a match has been found no need to run the whole loop (unique usernames)
                }
            }

            //if true means no username was matched (tempPlayer was initialised as -1)
            while(tempPlayer == -1)
            {
                System.out.println("\n    No such username exists.");
                System.out.println("    Please enter your username again, or type 'quit' to quit the login process: ");
                verification = scan.nextLine();
                //if user wants to quit
                if (verification.equalsIgnoreCase("quit")||verification.equalsIgnoreCase("'quit'"))
                {
                    break; //exits the username verification loop
                }
                else
                {
                    for (int i=0; i < playerList.size(); i++)
                    {
                        if (verification.equalsIgnoreCase(playerList.get(i).getUsername()))
                        {
                            tempPlayer = i;
                            break;  //exits the username verification loop
                        }
                    }
                }
            }

            //need to repeat this check in the case the user wants to quit, in order to exit the whole method
            if (verification.equalsIgnoreCase("quit")||verification.equalsIgnoreCase("'quit'"))
            {
                return; //will exit method as user no longer wants to continue
            }

            //if username is correct, we continue the verification process
            System.out.println("\n    Enter your password: ");
            verification = scan.nextLine();
            while(!playerList.get(tempPlayer).getPassword().equals(verification))
            {
                System.out.println("\n    You have entered a wrong password.");
                System.out.println("    Please enter your password again, or type 'quit' to quit the login process: ");
                verification = scan.nextLine();
                if (verification.equalsIgnoreCase("quit")||verification.equalsIgnoreCase("'quit'"))
                {
                    break; //escapes this while loop
                }
            }

            //need to repeat this check in the case the user wants to quit, in order to exit the whole method
            if (verification.equalsIgnoreCase("quit")||verification.equalsIgnoreCase("'quit'"))
            {
                return; //will exit method as user no longer wants to continue
            }

            //if the interpreter reaches this point it means that the user has managed to log in successfuly
            currentPlayer = tempPlayer; //changes the new currently logged in Player
            System.out.println("\n    Welcome back " + playerList.get(currentPlayer).getName() + "!");
            System.out.println("    Your total score is " + playerList.get(currentPlayer).getTotalScore() + ".");
            System.out.println();
        }
    }

    private void Play()
    {
        //if condition true then that means that no user is logged in
        if (currentPlayer == -1)
        {
            System.out.println("\n    You need to be logged in before you can play the game.");
            System.out.println("    Login by choosing L from the main menu.");
            System.out.println();
        }
        else
        {
           quit = true; //guit the game, as required by the instructions for this part of the project
        }
    }
}