//  GuessAWord.cpp  (c) Kari Laitinen

//  http://www.naturalprogramming.com

//  2013-11-14  File created.
//  2013-11-14  Last modification.

/*  This program is a simple computer game in which the player has to
    guess the characters of a word, or the player may also try to guess
    the whole word.

    This program demonstrates, among other things, various string
    operations.
*/

#include <iostream>
#include <string>
using namespace std ;

int main()
{
   cout << "\n This is a GUESS-A-WORD game.  \n" ;

   string word_to_be_guessed = "VIENNA" ;

   string guessed_characters( word_to_be_guessed.length(), '_' ) ;

   // Now guessed_characters refers to a string that has as many
   // underscore characters as the word to be guessed.

   bool game_is_over = false ;

   while ( game_is_over == false )
   {
      cout << " " + guessed_characters + "  " + "Give a character or word: " ;

      string player_input ;

      getline( cin, player_input ) ;

      // The following loop uses to bit operator & to convert the
      // player input to uppercase letters. (Note that this program may
      // not work with non-English letters.)

      for ( int character_index = 0 ;
                character_index < player_input.length() ;
                character_index ++ )
      {
         player_input[ character_index ] =
                             player_input[ character_index ] & 0xDF ;
      }

      if ( player_input.length() == 1 )
      {
         // The player gave a single character

         for ( int character_index = 0 ;
                   character_index < word_to_be_guessed.length() ;
                   character_index ++ )
         {
            if ( word_to_be_guessed[ character_index ] == player_input[ 0 ] )
            {
               guessed_characters[ character_index ] = player_input[ 0 ] ;
            }
         }

         if ( guessed_characters.find( '_' ) == string::npos )
         {
            // "_" is not a substring in guessed characters.
            // This means that all characters have been guessed.

            game_is_over = true ;

            cout << " " << guessed_characters << "  Congratulations! \n\n" ;
         }

      }
      else if ( player_input.length() > 1 )
      {
         // The player tried to guess the whole word.

         if ( player_input == word_to_be_guessed )
         {
            // The player made a correct guess.

            game_is_over = true ;

            cout << "\n Congratulations! \n\n"  ;
         }
      }
      else
      {
         game_is_over = true ;

         cout << " \n Game over. \n\n" ;
      }
   } 
}