#include <iostream>
#include <string>

#include <boost/function.hpp>

#include <boost/random/mersenne_twister.hpp>
#include <boost/random/uniform_int.hpp>
#include <boost/random/variate_generator.hpp>

using namespace std;


string GoodPhrase(int n);
string BadPhrase(int n);
string VaguePhrase(int n);

void PrintResponse(int n ,boost::function<string (int)> answer);

int main() {
    string question;
    int answer;

    boost::mt19937 rng(time(NULL));
    boost::uniform_int<> dist(0,19);
    boost::variate_generator<boost::mt19937&, boost::uniform_int<> >
                     result(rng,dist);

    while(1) {
       cout << endl;
       cout << "Enter a question for the might eight ball =>";
       getline(cin, question);

       answer = result();
       if (answer < 10) {
         PrintResponse(answer, GoodPhrase);
       } else if (answer < 15) {
         PrintResponse(answer-10,BadPhrase);
       } else {
         PrintResponse(answer-15,VaguePhrase);
       }

    }
}


void PrintResponse(int n ,boost::function<string (int)> answer){
     cout << "*******************************************" << endl;
     cout << "* The magic eight ball responds with      * " << endl;
     cout << "\t\t" <<  answer(n) << endl;;
     cout << "*  And thus it was spoken.                *" << endl;
     cout << "*******************************************" << endl;
}

string GoodPhrase(int n) {
   switch(n) {
       case 0: return "It is certain";
       case 1: return "It is decidedly so";
       case 2: return "Without a doubt";
       case 3: return "Yes definitely";
       case 4: return "You may rely on it";
       case 5: return "As I see it yes";
       case 6: return "Most likely";
       case 7: return "Outlook good";
       case 8: return "Yes";
       case 9: return "Signs point to yes";
       default: return "Yep";
   }
}

string VaguePhrase(int n){

   switch(n) {
         case 0: return "Reply hazy try again";
         case 1: return "Ask again later";
         case 2: return "Better not tell you now";
         case 3: return "Cannot predict now";
         default: return "Concentrate and ask again";
   }
}

string BadPhrase(int n){
    switch(n) {
        case 0: return "Reply hazy try again";
	case 1: return "Ask again later";
	case 2: return "Better not tell you now";
	case 3: return "Cannot predict now";
	default: return "Concentrate and ask again";
    }
}