/*
Assignment #6 Part #1 TIC TAC TOE
*/

#include <iostream>
#include <iomanip>
#include <cmath>
#include <cstdlib>

using namespace std;


// initialize takes a nine element gameBoard and doesn't return anything.
// It sets the elements of the gameBoard to integers from 1 to 9 starting
// from the upper left.
void initialize(int gameBoard[]){
     for(int i=0;i<9;i++){
        gameBoard[i]=i+1;
     }
}


// playCell takes a player (0 for "O", 1 for "X"), a position (1 to 9),
// and the nine element gameBoard, and returns true if the move is legal
// (i.e. that spot is not yet taken), and false otherwise.  If the move is
// legal it changes the position to that players number (10 for "O", 11 for "X").
// If the player or position input is invalid, it returns false;
bool playCell(int player, int position, int gameBoard[]){
    if(gameBoard[position-1]!=-1 && gameBoard[position-1]!=0){
        gameBoard[position-1]=player*-1;
         return true;
    }else{
        return false;    
    }
    
   
}


// winCheck checks the gameBoard for a winner.
// Returns 0 if "O" has won; 1 if "X" has won; and -1 if no winner (yet).
// It assumes the board has only 1 winner.
// (the "const" indicates that we will not change the gameBoard in this function.)
int winCheck (const int gameBoard[]){
    for(int i=0;i<3;i++){//horizontal check
        if(gameBoard[i]==-1 &&gameBoard[i+1]==-1 &&gameBoard[i+2]==-1){
            return 1;
        }
        if(gameBoard[i]==0 &&gameBoard[i+1]==0 &&gameBoard[i+2]==0){
            return 0;
        }
    }
    for(int i=0;i<3;i++){//vertical check
        if(gameBoard[i]==-1 &&gameBoard[i+3]==-1 &&gameBoard[i+6]==-1){
            return 1;
        }
        if(gameBoard[i]==0 &&gameBoard[i+3]==0 &&gameBoard[i+6]==0){
            return 0;
        }
    }
    
	//diagonal check
    if(gameBoard[0]==-1 &&gameBoard[4]==-1 &&gameBoard[8]==-1){
        return 1;
    }
    if(gameBoard[0]==0 &&gameBoard[4]==0 &&gameBoard[8]==0){
        return 0;
    }
    
    if(gameBoard[2]==-1 &&gameBoard[4]==-1 &&gameBoard[6]==-1){
        return 1;
    }
    if(gameBoard[2]==0 &&gameBoard[4]==0 &&gameBoard[6]==0){
        return 0;
    }
    
    
    return -1;
}


// printBoard takes the gameBoard and doesn't return anything.
// It prints out the current state of the board to the display.
// (the "const" indicates that we will not change the gameBoard in this function.)
void printBoard(const int gameBoard[]){
    int count=0;
    for(int i=1;i<=7;i++){
        if(i%2==1){
            cout<<"\n+-----+-----+-----+\n";
        }
        else{
                cout<<"|";
            for(;;){
                //takes care of X and O
                if(gameBoard[count]==-1){
                    cout<<"  X  |";
                }else if(gameBoard[count]==0){
                    cout<<"  O  |";
                }else{
                    cout<<"  "<<gameBoard[count]<<"  |";
                }
                count++;
                if(count==9 || count%3==0){
                    break;    
                }
            }
        }
    }
    cout<<"\n";
}


// (getIntBP is an improved version of getInt written in Assignment #5, Question #1,
// as it is "bullet-proof".)
// Returns an integer value from the user between minimum and 
// maximum, inclusive.
// We assume that the calling function has output the initial 
// request for input.
// This function will check the value entered and output an error 
// message until a value in the correct range is entered.
// This function deals correctly with non-integer inputs.
int getIntBP(int minimum, int maximum){
    int input;
    for(;;){
        cin>>input;
        while (cin.fail()) { 
            cout << "Garbage data was entered - please try again: ";
            cin.clear (); // reset error flag
            cin.ignore (INT_MAX, '\n');  // flush remainder of the bad input line
            cin >> input;//asks for input
        }
		//checks the validity of the input
        if(input<=maximum && input>=minimum){
            return input;
            break;
        }else{
            cin.ignore (INT_MAX, '\n');    
        }
        cout<<"error please enter valid data\n";
    }
}


int main() {
	
	int board[9], // the tic-tac-toe board
		move, // the move number: 0 to 8
		turn, //  0 = "O"'s turn; 1 = "X"'s turn
		playerFirst=0, // we start with "O" going first
		winPlayer=-1; // 0 is "O", 1 is "X", -1 is no winner yet or tie
	char player[2] = {'O','X'};	// a character array 'O' or 'X'
	
	// play until user enters 0 to stop
	for(;;) { 

		// initialize and print the board
		initialize(board);
		printBoard(board);
		
		// loop once for every turn (max of 9)
		for (move=0; move<9; move++) {
			//system ("PAUSE");
			turn = (move+playerFirst)%2; // 0 (O) or 1 (X)'s turn
			
			// that player makes a move
			for(;;){
				cout << "Player " << player[turn] << " choose cell to play in: ";
				if (playCell(turn,getIntBP(1,9),board)) {
					break;	
				}
				cout << "Cell already used" << endl;
			} // end for
			
			printBoard(board);	// show the board
			
			// check for a winner if this is the fifth move or more (moves start at 0)
			if (move>3) {
				winPlayer=winCheck(board); // look for a winner if 5 or more moves
				if (winPlayer!=-1) { // we have a winner
					cout << "Player " << player[winPlayer] << " wins!\n\n";
					playerFirst=(winPlayer+1)%2; // other player goes first next time
					break; // this game is over
				}//end if
			}//end if
		} // end for move
		
		// check for no winner
		if (winPlayer==-1){		// no one won
			cout << "Game is a draw.\n\n";
			playerFirst=(playerFirst+1)%2;	// Flip the first player for next game
		} // end if
		
		cout << "Do you wish to play again (Enter 1 for Yes or 0 for No)?: ";
		// if user enters 0, we exit, otherwise continue
		if (!getIntBP(0,1)) {
			break;
		}
	} // end for
	
	system ("PAUSE"); return 0;

} // end main