public class HangmanLogic {

    private String word;
    private String guessedLetters;
    private int numberOfFaults;
    private String letter;
    private String hiddenword;

    public HangmanLogic(String word) {
        this.word = word.toUpperCase();
        this.guessedLetters = "";
        this.numberOfFaults = 0;
    }

    public int numberOfFaults() {
        return this.numberOfFaults;
    }

    public String guessedLetters() {
        return this.guessedLetters;
    }

    public int losingFaultAmount() {
        return 12;
    }

    public void guessLetter(String letter) {
        this.letter =letter;
        if(guessedLetters.contains(this.letter)){ }

        else if(!word.contains(this.letter)){
            this.numberOfFaults+=1;
            this.guessedLetters+=letter;

        }else if(word.contains(letter)){
            this.guessedLetters+=letter;

        }

        // if the letter has already been guessed, nothing happens

        // it the word does not contains the guessed letter, number of faults increase
        // the letter is added among the already guessed letters
    }

    public String hiddenWord() {
        String hiddenword =word;

        hiddenword=hiddenword.replaceAll("[A-Z]","_");

        for (int i = 0; i < word.length(); i++){
            hiddenword=hiddenword.replace(hiddenword, "_");
        }

        System.out.println(hiddenword);

        while(!guessedLetters.equals(4)){

             if(word.contains(letter)){
                int letterplace= word.indexOf(letter);
                 String hiddenword2= hiddenword.substring()
             }

        }
        // create the hidden word by interating through this.word letter by letter
        // if the letter in turn is within the guessed words, put it in to the hidden word
        // if the letter is not among guessed, replace it with _ in the hidden word

        // return the hidden word at the end
        return hiddenword;
    }
}