#include <iostream>
#include <cstdlib>
#include <string>

using namespace std;

const int ANSWER_COUNT = 20;

int main() {
    string question,
           answer,
	   playAgain;
    bool   keepPlaying = true,
           goodValue = false;
    int    randValue,
           i;

    srand(time(NULL));
    
    while(keepPlaying) {
        cout << endl;
        cout << "Enter a question for the magic 8 ball => ";
	getline(cin, question);

        // I'm going to store the rand value in a variable for 
	// debugging purposes.
	randValue = rand() % ANSWER_COUNT;

        // convert the random number to a string. 
	switch(randValue) {
	   case 0:
	       answer = "It is certain.";
	       break;
	   case 1:
	       answer = "It is decidedly so";
	       break;
	   case 2:
	       answer = "Without a doubt";
	       break;
	   case 3:
	       answer = "Yes, definitely";
	       break;
	   case 4:
	       answer = "You may rely on it";
	       break;
	   case 5:
	       answer = "As I see it, yes";
	       break;
	   case 6:
	       answer = "Most likely";
	       break;
	   case 7:
	       answer = "Outlook good";
	       break;
	   case 8:
	       answer = "Yes";
	       break;
	   case 9:
	       answer = "Signs point to yes";
	       break;
	   case 10:
	       answer = "Reply hazy try again";
	       break;
	   case 11:
	       answer = "Ask again later";
	       break;
	   case 12:
	       answer = "Better not tell you now";
	       break;
	   case 13:
	       answer = "Cannot predict now";
	       break;
	   case 14:
	       answer = "Concentrate and ask again";
	       break;
	   case 15:
	       answer = "Don't count on it";
	       break;
	   case 16:
	       answer = "My reply is no";
	       break;
	   case 17:
	       answer = "My sources say no";
	       break;
	   case 18:
	       answer = "Outlook not so good";
	       break;
	   case 19:
	       answer = "Very doubtful";
	       break;
	   // if you add a new case, make sure to change  ANSWER_COUNT
	   default:
	       answer = "Error, the 8 ball is really confused.";
	}

	// print the answer
	cout << "You asked: \"" << question << "\"" << endl;
	cout << "The 8 ball replies: \"" << answer << ".\"" << endl;

	cout << endl;
	cout << endl;

	goodValue = false;

        // find out if the player wants to play again.
	while (!goodValue) {
	    cout << "Do you want to ask another question? (yes/no) => ";
	    getline(cin,playAgain);

            // make the entire string upper case.
	    i = 0;
	    while(i < playAgain.size()) {
	        playAgain.at(i) = tolower(playAgain.at(i));
		i++;
	    }

            // make a decision based on the answer.
	    if (playAgain == "yes") {
	        goodValue = true;
		cout << "Ok, we will keep playing" << endl;
	    } else if (playAgain == "no") {
	        goodValue = true;
		keepPlaying = false;
		cout << "Ok, we will stop playing" <<endl;
	    } else {
	       cout << playAgain << " Is not yes/no, please enter yes or no"
	            << endl;
	    }
	}

    }

    return (0);
}