import java.util.List;
import java.util.Scanner;

//Class to handle registration and login processes separately from the game controller
public class RegistrationAndLogin

{

    //Method of type Player which handles the registration process and returns the new Player object registered
    public Player Register(List<Player> thePlayerList)
    {
        //creates temporary variables to hold the player's information during registration
        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(thePlayerList);
        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 new player object using the player's details, with default score & number of games player equal to 0
        Player newPlayer = new Player(tempName,tempSurname,tempUsername,tempPassword, 0, 0);

        //adds the new player's details to the array list
        return newPlayer;
    }

    private String setName()
    {
        Scanner scan = new Scanner(System.in);
        System.out.print("\n    Enter your first name: ");
        String name = scan.nextLine();
        while (!InputValidation.nameValidation(name)) //while the user's input does not pass the validation, prompt to enter new 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 (!InputValidation.nameValidation(surname))//while the user's input does not pass the validation, prompt to enter new surname
        {
            System.out.print("\n    Please enter your last name again: ");
            surname = scan.nextLine();
        }
        return surname;
    }

    private String setUsername(List<Player> thePlayerList)
    {
        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();

        //program will prompt user to choose a different username if the username they have entered does not pass
        //the validation and if another user has already registered with the same username
        while ((!InputValidation.usernameValidation(username)) || (!isUsernameAvailable(username, thePlayerList)))
        {
            System.out.print("\n    Please enter a new username: ");
            username = scan.nextLine();
        }
        return username.toLowerCase(); //all usernames are case-insensitive
    }

      public boolean isUsernameAvailable(String aUsername, List<Player> thePlayerList)
    {
        boolean valid = true;
        for (int i=0; i < thePlayerList.size(); i++) //loops through the player list
        {
            //for every player, checks whether the user's input matches an already registered player's username
            if (aUsername.equalsIgnoreCase(thePlayerList.get(i).getUsername()))
            {
                System.out.print("\n    This username is already in use.");
                valid = false; //if it does, the method returns a false value so the loop in the calling method can repeat
                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 (!InputValidation.passwordValidation(password)) //while the user's input does not pass the validation, prompt to enter new password
        {
            System.out.print("\n    Please enter a new password: ");
            password = scan.nextLine();
        }
        return password;
    }

    //method of type integer which returns the value of the player logged in
    //if the user quits during the login process, the value returned will be the initial value of the current player
    //if the user successfuly logs in, the value returned will be that of the new user
    public int Login(List<Player> thePlayerList, int theCurrentPlayer)
    {
        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 (thePlayerList.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();
            return theCurrentPlayer; //redundant
        }
        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 < thePlayerList.size(); i++)
            {
                if (verification.equalsIgnoreCase(thePlayerList.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 < thePlayerList.size(); i++)
                    {
                        if (verification.equalsIgnoreCase(thePlayerList.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 theCurrentPlayer; //will exit method as user no longer wants to continue
                //the player logged in is the same one as before the login process was invoked
            }

            //if username is correct, we continue the verification process
            System.out.println("\n    Enter your password: ");
            verification = scan.nextLine();
            while(!thePlayerList.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 theCurrentPlayer; //will exit method as user no longer wants to continue
                //the player logged in is the same one as before the login process was invoked
            }

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

        }
    }
}