// Add a DO-WHILE to implement a menu
// to repeat the game until the user
// indicates they want to terminate
// the program.

#include <iostream>
#include <cstdlib>
#include <ctime>
using namespace std;

int main()
{
	string user_selection; // user choice (rock, paper, scissors)
	string comp_selection; // computer choice (rock, paper, scissors)
	int comp_int;		   // computer choice as an integer
	int user_int;		   // user choice as an integer
	bool flag; 			   // error flag checks for invalid input

	srand(time(NULL));     // seeds random number generator

	// game menu
	cout << "Welcome to my ROCK, PAPER, SCISSORS game." << endl;
	cout << "please type \"rock\", \"paper\", or \"scissors\" (case sensitive)" << endl;
	cin >> user_selection;

	// computer randomly picks a number 0-2
	comp_int = rand() % 3;

	// set error flag to false
	flag = false;

	//convert users choice to 0, 1 or 2 ( 0 = rock, 1 = paper, 2 = scissors)
	if(user_selection == "rock"){
		user_int = 0;
	}else if (user_selection == "paper"){
		user_int = 1;
	}else if (user_selection == "scissors"){
		user_int = 2;
	}else{
		// input is invalid. set error flag to true
		flag = true;
	}

	// computer's selection is changed from an integer to a string.
	// (rock, paper, or scissors)
	if(comp_int == 0){
		comp_selection = "rock";
	}else if (comp_int == 1){
		comp_selection = "paper";
	}else{
		comp_selection = "scissors";
	}

	// if error flag is true, input is invalid, otherwise calculate the winner and
	// print results to the screen.
	if(flag){
		cout << "Invalid input" << endl;
	}else if(user_int == comp_int){
		cout << user_selection << " ties with " << user_selection << "!" << endl;
	}else if (user_int == (comp_int + 1) % 3){
		cout << "You WIN! " << user_selection << " beats " << comp_selection << endl;
	}else{
		cout << "You Lose. " << user_selection << " loses to " << comp_selection << endl;
	}



	return 0;
}