using System;
using System.Collections.Generic;
using System.Text;

namespace DomeWrinklesCurlc // A pug-themed version of rock|paper|scissors
{
    class Program
    {
        static void Main(string[] args)
        {
            Greeting();
            //TODO: implement a static gamestats object with these variables as properties
            int result = 0;  // Result of this round.  1 = win 0 = tie -1 = lose
            int score = 0; // Score = wins - losses
            int wins = 0; //Number of times the player has won a round
            int rounds = 0; // Number of rounds played
            
            while (PlayAgain())
            {
                rounds++;
                Console.WriteLine("Round " + rounds);
                result = PlayRound();
                score = score + result;
                //Console.WriteLine("score so far: " + score);
                if (result == 1)
                {
                    wins = wins + 1;
                }
                //Console.WriteLine("Wins so far: " + wins);
                Console.WriteLine("\n\nPlay again?  Y| N:  ");
            }

            Console.WriteLine("\n\n\nYou played " + rounds + " games.");
            Console.WriteLine("Your score: " + score + ".");
            Console.WriteLine("You won " + wins + " games.");
            Console.WriteLine("\n\n\nI like pugs.");
            Console.WriteLine("\n\nPress Enter to quit.");
            Console.ReadLine();
        }

        private static string SanitizeInput(string s)
        {
            //returns the first character of the input string, in upper case
            if (s.Length > 0) //rewrite to use proper exception handling; throws exception if empty string.
            {
                s = s.ToUpper().Substring(0, 1);
            }
            else 
            {
                s = " ";
            }
            return s;
        }

        private static void Greeting()
        {
             //Greet player
            Console.WriteLine("A cute little puggy appears!\n\n");
            Console.WriteLine("Pug:  \"I am Pug!\"\n      *wag* *wag*\n      *pant* *pant*\n      \"Want to play Dome Wrinkles Curl?\"\n");
            Console.Write("Play?  Y|N: ");
        }

        private static string TakeInput()
        {
            string input = Console.ReadLine();
            input = SanitizeInput(input);
            return input;
        }

        private static string ComputerMove() //Generates a random move for the AI to play
        {
            Random r = new Random();
            int n = (r.Next() % 3);

            //plays a Dome move for the AI
            string move = "";
            Console.WriteLine("");
            if (n == 0)
            {
                Console.WriteLine("Pug:  \"Dome!\"");
                move = "D";
            }
            //plays a Wrinkle move for the AI
            if (n == 1)
            {
                Console.WriteLine("Pug:  \"Rub my wrinkles!\"");
                move = "W";
            }
            //plays a Curl move for the AI 
            if (n == 2)
            {
                Console.WriteLine("Pug:  \"Whirl my curl!\"");
                move = "C";
            }
            return move;
        }

        private static bool PlayAgain()
        {
            bool inputIsValid = false;
            bool playAgain = false; 

            string PlayYesNo = TakeInput();

            while (inputIsValid == false)
            {
                if (PlayYesNo.Equals("Y"))
                {
                    Console.WriteLine("\nPug:  \"OK Let's play!  Boof!\"\n\n");
                    inputIsValid = true;
                    playAgain = true;
                }
                else if (PlayYesNo.Equals("N"))
                {
                    Console.WriteLine("\nPug:  \"No?  I go sleep sleep.\"");
                    inputIsValid = true;
                    playAgain = false;
                }
                else
                {
                    Console.WriteLine("\n\nPug:  *Head tilt*\n\n      \"Got a treat?\"");
                    Console.Write("\n\n\nPlay?  Y|N: ");
                    PlayYesNo = TakeInput();
                }
            }

            return playAgain;
        }

        private static string DetermineWinner(string player1, string pug)
        {
            //Rules:  
            //Game plays like rock|paper|scissors
            //
            //Wrinkles covers Dome
            //Dome straightens Curl
            //Curl smooths out Wrinkles

            if (player1.Equals(pug)) //tie game
            {
                Console.WriteLine("\nTIE!");
                return "tie";
            } 
            else if ((player1.Equals("D") && pug.Equals("C")) || (player1.Equals("C") && pug.Equals("W"))) //player wins
            {
                if (player1.Equals("D")) { Console.WriteLine("Dome straightens curl.");}
                if (player1.Equals("W")) { Console.WriteLine("Wrinkles cover dome."); }
                if (player1.Equals("C")) { Console.WriteLine("Curl wags away wrinkles."); }
                Console.WriteLine("\nYou win!");
                return "win";
            }
            else  //computer wins
            {
                Console.WriteLine("\nPug:  \"Pug wins again!\"");
                return "lose";
            }
        }

        private static int PlayRound() //returns score for ongoing tally after each round
        {
            int roundscore = 0;
            Console.WriteLine("\n\nPug:  \"OK, u play ur move.  Rau!\"");
            Console.Write("(D)ome|(W)rinkles|(C)url: ");
            string playerMove = TakeInput();
            //validate your move
            bool validMove = false;
            while (validMove == false)
            {
                if (playerMove.Equals("D") || playerMove.Equals("W") || playerMove.Equals("C"))
                {
                    //calculate winner
                    string pugMove = ComputerMove();
                    string result = DetermineWinner(playerMove, pugMove);
                    if (result == "win")
                    {
                        roundscore = 1;
                    }
                    if (result == "lose")
                    {
                        roundscore = -1;
                    }
                    if (result == "tie")
                    {
                        roundscore = 0;
                    }
                    validMove = true;
                }
                else
                {
                    Console.Write("\n\nRau!  You have to enter a D, W, or C.  Try again:  ");
                    playerMove = TakeInput();
                }
            }

            return roundscore;
        }
    }
}