// QuestionsMain contains a main program that plays N-Questions with a user.
// It asks the user where to read the questions from before playing, and always
// writes the result to that file to make itself better next time.

import java.io.*;
import java.util.*;

public class QuestionsMain {
    public static void main(String[] args) throws IOException {
        Scanner console = new Scanner(System.in);

        System.out.println("Welcome to CSE 143 Game of N-Questions!");
        System.out.println();

        System.out.print("Which questions file would you like to use? ");
        String filename = console.nextLine().trim();

        /* Create the Questions File if it doesn't exist */
        File questionsFile = new File(filename);
        if (!questionsFile.exists()) {
            questionsFile.createNewFile();
        }

        Scanner questions = new Scanner(questionsFile);
        QuestionsGame game = createGame(questions, console);

        System.out.print("Let's play!  ");
        do {
            System.out.println("Please choose your object, and I'll " +
                               "start guessing.");
            System.out.println("Press Enter when you're ready to begin!");
            console.nextLine();
            game.play();
            System.out.println();
            game.saveQuestions(new PrintStream(questionsFile));
            System.out.print("Do you want to play again (y/n)? ");
        } while (console.nextLine().trim().toLowerCase().startsWith("y"));
    }

    public static QuestionsGame createGame(Scanner questions, Scanner console) {
        /* Check if the file has anything in it.  If it does, use it.
         * Otherwise, initialize a new game. */
        if (!questions.hasNext()) {
            return new QuestionsGame(getInitialObject(console));
        }
        else {
            return new QuestionsGame(questions);
        }
    }

    public static String getInitialObject(Scanner console) {
        System.out.println("There are no objects to guess in that " +
                           "questions file.");
        System.out.print("Can you provide me with an initial object? ");
        return console.nextLine().toLowerCase().trim();
    }
}