// header files
#include "Console_IO_Utility.h"

// global constants
    // none

// function prototypes
int generateRandChoice();
char playGame();
char whoWins();

// main program
int main()
    {
     // show title
        // function: printString, printEndline(s)
    printEndline();
    printString( "Rock / Paper / Scissors" );
    printEndline();


	 // initialize variables/functions
     int userInput;
	   char winner;


	 // get user input
        // Display options of user input
            // functions: printString, printEndline
	 printString("Options to choose:");
	 printEndline();
	 printString("0 - Scissors");
	 printEndline();
	 printString("1 - Paper");
	 printEndline();
	 printString("2 - Rock");
	 printEndline();

   // get users value for rock/paper/scissors
      // function: promptForInteger, printEndline
	 userInput = promptForInteger("Enter your value: ");
	 printEndline();

  // check for valid user input, if valid,
  if (userInput > -1 && userInput < 3)
    {
     // use playGame
     winner = playGame(userInput);
     // display winner.
       // functions: printString, printCharacter, printEndline
     printString("The winner is: ");
     printCharacter(winner);
     printEndline();
    }
    else
    {
      // else, return zero and end the program,
         // print "Sorry no such option! Try again"
      printString("Sorry no such option! Try again");
    }
    return 0;
   }

// supporting functions

/*
Name: playGame
Process: plays rock paper scissors game, generates random choice for AI player
         and returns who won the game
Function input/parameters: previously chosen players input
                            rock / paper / scissors represented by 2 / 1 / 0
Function output/parameters: none
Function output/returned: character which represents who won the game
Function input/keyboard: none
Device output/file: none
Dependencies: generateRandChoice, whoWins
*/

char playGame(int userInputValue)
{
  // initialize variables
  int computerChoice;

  // calculate computerChoice
  computerChoice = generateRandChoice();

  // return who whoWins
  return whoWins(userInputValue, computerChoice);

}

/*
Name: whoWins
Process: based on user input and randomly generated value decides who wins
         via series of decision making statements
Function input/parameters: previously chosen players input
                            rock / paper / scissors represented by 2 / 1 / 0
                            and randomly generated number of the same range
Function output/parameters: none
Function output/returned: character which represents who won the game
                            'U' - user; 'R' - random (AI); 'F' - friendship.
Function input/keyboard: none
Device output/file: none
Dependencies: none
*/

char whoWins(int playerInputValue, int computerChoice)
{
  // define variables
  char winnerCharacter;
  // get function input
    // given by values: playerInputValue, computerChoice

// do calculations/comparisons
  if (playerInputValue == computerChoice)
  {
    // check to see if the player and computer picked the same choice
    winnerCharacter = 'F';
  }
  else
  {
    // otherwise, check which values the player chose versus the computer.
    if(playerInputValue == 0 && computerChoice == 1)
    {
      // player loses, computer wins
      winnerCharacter = 'R';
    }
    else if (playerInputValue == 1 && computerChoice == 0)
    {
      // player wins, computer loses
      winnerCharacter = 'U';
    }
    else if (playerInputValue == 2 && computerChoice == 0)
    {
      // player wins, computer loses
      winnerCharacter = 'U';
    }
    else if (playerInputValue == 0 && computerChoice == 2)
    {
      // player loses, computer wins
      winnerCharacter = 'R';
    }
    else if (playerInputValue == 1 && computerChoice == 2)
    {
      // player wins, computer loses
      winnerCharacter = 'U';
    }
    else
    {
      // player loses, computer wins. (playerInputValue == 2, computerChoice == 1)
      winnerCharacter = 'R';
    }
  }

// return output
return winnerCharacter;
}

/*
Name: generateRandChoice
Process: based on user input and randomly generated value decides who wins
         via series of decision making statments
Function input/parameters: previously chosen players input
                            rock / paper / scissors represented by 2 / 1 / 0
                            and randomly generated number of the same range
Function output/parameters: none
Function output/returned: character which represents who won the game
                            'U' - user; 'R' - random (AI); 'F' - friendship.
Function input/keyboard: none
Device output/file: none
Dependencies: none
*/
int generateRandChoice()
	{
     // initialize variables
	 int randNum;

     // computations
        // initialize random seed
	 srand(time(0));
        // generate random number between 0 and 2 (inclusive)
	 randNum = rand() % 2 + rand() % 2;

     // return result
	 return randNum;
	}