import java.util.InputMismatchException;
import java.util.Scanner;
import java.util.Random;

public class SarahRyuGame
{
    public static void main(String[] arguments)
    {
        //declare main variables
        int choice=0;
        Scanner input = new Scanner(System.in);
        String[] usernames = new String[0];
        String[] passwords = new String[0];
        int[] scores = new int[0];
        String enteredUsername = "", enteredPassword = "", verifiedPassword ="";
        int recentScore;



        //main loop until choice = 4
        do
        {
            printMenu();
            choice = getChoice();

            if(choice == 1) //register - get username and password
            {
                System.out.println("\nREGISTER");

                //get username
                System.out.print("Enter username: ");
                enteredUsername = input.next();

                //check to see if username already exists
                while(findUser(enteredUsername, usernames) != -1)
                {
                    System.out.print("Username already exists. Enter new username: ");
                    enteredUsername = input.next();
                }

                //call method createPassword to get password and verify entered the same one twice.
                createPassword();

                //add the new user info to all arrays - creates a copy that is one larger than before
                usernames = addToArray(enteredUsername, usernames);
                passwords = addToArray(enteredPassword, passwords);
                scores = addToArray(0,scores);

                System.out.printf("%nWelcome %s.  You have been registered.%n%n",enteredUsername);

            }
            else if(choice == 2) //login to account and play game
            {
                int currentUserIndex;

                if(usernames.length == 0)//no users yet, return to main menu
                {
                    System.out.println("No account exists.  Please register first.");
                }
                else //have registered so now can login with username and password
                {
                    System.out.println("\nLOGIN");

                    //get username
                    System.out.print("Enter username: ");
                    enteredUsername = input.next();
                    currentUserIndex = findUser(enteredUsername, usernames);
                    while(currentUserIndex ==  -1)
                    {
                        System.out.print("User does not exist.");
                        System.out.print("Enter username: ");
                        enteredUsername = input.next();
                        currentUserIndex = findUser(enteredUsername, usernames);
                    }

                    //get password
                    System.out.print("Enter password: ");
                    enteredPassword = input.next();
                    while(!passwords[currentUserIndex].equals(enteredPassword))
                    {
                        System.out.print("Invalid password. ");
                        System.out.print("Enter password: ");
                        enteredPassword = input.next();
                    }

                    //success!
                    System.out.printf("%nWelcome %s.  You have successfully logged in.%n%n",usernames[currentUserIndex]);
                    System.out.println("Now let's play!");

                    //play game, get score from game
                    recentScore = playGame(usernames[currentUserIndex]);

                    //TASK 10! update score in array
                    scores[currentUserIndex] = recentScore;

                }
            }
            else if(choice == 3) //display scoreboard
            {
                displayScoreboard(usernames, scores);
            }

        }while(choice != 4);

    }//end main


        //methods

    public static String createPassword()
    {
       Scanner input = new Scanner(System.in);
            String enteredPassword, verifiedPassword;
        do
        {
            System.out.print("Enter password: ");
            enteredPassword = input.next();
            System.out.print("Reenter password: ");
            verifiedPassword = input.next();
            if(!enteredPassword.equals(verifiedPassword))
            {
                System.out.println("Your passwords do not match!  Please try again. ");
            }
        }while(!enteredPassword.equals(verifiedPassword));
        return verifiedPassword;
    }
    //add comments here...addToArray() does this...
    public static String[] addToArray(String newWord, String[] oldArray)
    {
        //create new array that is 1 bigger than old array
        String[] newArray = new String[oldArray.length+1];

        //copy everything from oldArray to newArray
        for(int i = 0; i < oldArray.length; i++)
        {
            newArray[i] = oldArray[i];
        }

        //in the last spot, add the newWord
        newArray[newArray.length-1] = newWord;

        //now return the pointer to the newArray
        return newArray;
    }

    //add comments here...addToArray() does this...
    public static int[] addToArray(int newNum, int[] oldArray)
    {
        //create new array that is 1 bigger than old array
        int[] newArray = new int[oldArray.length+1];

        //copy everything from oldArray to newArray
        for(int i = 0; i < oldArray.length; i++)
        {
            newArray[i] = oldArray[i];
        }

        //in the last spot, add the newWord
        newArray[newArray.length-1] = newNum;

        //now return the pointer to the newArray
        return newArray;
    }

    //add comments here...displayScoreboard() does this...
    public static void displayScoreboard(String[] usernames, int[] scores)
    {
        System.out.println("USER    SCORE");
        for(int i = 0; i < usernames.length; i++)
        {
            System.out.printf("%s:    %d%n", usernames[i], scores[i]);
        }
    }

    //add comments here...getChoice() does this...
    public static int getChoice()
    {
        Scanner input = new Scanner(System.in);
        System.out.print("Enter choice: ");
        int choice = 0;
        try
        {
            choice = input.nextInt();
            while (choice < 1 || choice > 4)
            {
                System.out.println("Invalid choice.");
                System.out.print("Enter choice: ");
                choice = input.nextInt();
            }
        }

        //add checks for invalid input - try catch?  and check for 0-3 valid or not
        catch(InputMismatchException e)
                {


                }
                   return choice;

    }

    //add comments here...findUser() does this...
    public static int findUser(String newUsername, String[] usernames)
    {
        //check to see if newUsername already exists in the usernames array
        for(int i = 0; i < usernames.length; i++)
        {
            //if exists, return index of user in the array
            if(newUsername.equals(usernames[i]))
                return i;
        }

        //if never found, return -1
        return -1;
    }

    //add comments here...playGame() does this...
    public static int playGame(String name){
        //create the objects
        Scanner input = new Scanner(System.in); //used for input
        Random randomNumbers = new Random(); //used to generate a random number

        //declare the variables
        int theNumber = randomNumbers.nextInt(100) + 1; //pick a random integer from 1 to 100
        int numberGuesses = 0; //keep track of how many guessed
        boolean correctGuess = false; //has the number been guessed yet?
        int guess; //the guess by user

        System.out.printf("%nWelcome %s to Professor Steck's Number Guessing Game.%n", name);
        System.out.println("I am thinking of a number between 1 and 100...");

        //cause a short delay while "thinking", 1000 is one second
        try
        {
            Thread.sleep(2000);
        }
        catch(InterruptedException ex)
        {
            Thread.currentThread().interrupt();
        }


        //ask for a guess until it is correct
        while(correctGuess == false) //could also write this as !correctGuess
        {
            //get a guess from the user
            System.out.printf("%nEnter your guess: ");
            guess = input.nextInt();
            System.out.println();
            numberGuesses++; //increment the number of guesses by 1

            //determine if the number guessed is correct
            if(guess == theNumber)
            {
                System.out.print("Yes! You are correct! ");
                System.out.printf("It took you %d guesses. %n%n", numberGuesses);
                correctGuess = true;
            }
            else
            {
                //if not correct, determine whether guess was too high or too low
                if(guess > theNumber) //guess too high
                {
                    System.out.print("Sorry, you are not correct.");
                    System.out.printf(" Your guess was too high. %n");
                }
                else //guess too low
                {
                    System.out.print("Sorry, you are not correct.");
                    System.out.printf(" Your guess was too low. %n");
                }
            }
        } //end while loop
        return numberGuesses;
    }

    //add comments here...printMenu() does this...
    public static void printMenu()
    {
        System.out.println("\nMAIN MENU");
        System.out.println("1. Register");
        System.out.println("2. Login");
        System.out.println("3. Display scoreboard");
        System.out.println("4. Exit");
    }

}//end class