package hangmanModel;

/**
* Represents a word in the hangman game.
* An AWord can be empty or non-empty.
*   When it is empty it contains nothing.
*   When it is non-empty, it contains a character and another AWord.
* Each character in a non-empty AWord can be hidden or visible.
*   When hidden, its String representation is "_".
*   When visible, its String representation is that of the character itself.
* @author D. X. Nguyen
*/
public abstract class AWord
{
    /**
     * Matches an input character with all the characters in this AWord, and
     * returns whether there is a match in the word.
     * Side effect: Makes all matching characters visible.
     * @param c the character to be matched.
     * @return whether there is a match in the word.
     */
    public abstract boolean matchAll(char c);

    /**
     * Helper method for match.  Called by the non-empty parent AWord to help
     * match the remaining characters in the word, given a boolean flag marking
     * whether or not there is a match so far.
     * @param c the character to be matched.
     * @param b whether there is a match previously in the word.
     * @return whether there is a match in the word.
     */
    protected abstract boolean helpMatchAll(char c, boolean b);

    /**
     * @return whether all characters  of the word are visible.
     */
    public abstract boolean isAllVisible();
}