#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>

struct state{ // defined
	int state; // 0 is tie, 1 is user loss, 2 is user win, 3 is ongoing game
	int moves;
};

struct square{ // one square of the board
	int value; // 1 is x, 2 is o
	char sign; // no space used
};

struct square s[9]; //set up the struct
struct state gamestate = {0,0}; //nothing

void setUpGame(){ // setup the game
	int i = 0;
	for(i = 0; i < 9; i++){
		s[i].value = 0;
	   	s[i].sign = ' ';
	}
	gamestate.moves=0;
	printf("\nHi user! You're \"x\"! I'm \"o\"! Good Luck :)\n");
}

void displayBoard(){// displays the game board
	printf("\n %c | %c | %c\n", s[6].sign, s[7].sign, s[8].sign);
	printf("-----------\n");
	printf(" %c | %c | %c\n", s[3].sign, s[4].sign, s[5].sign);
	printf("-----------\n");
	printf(" %c | %c | %c\n\n", s[0].sign, s[1].sign, s[2].sign);
}

void getHumanMove(){ // get move from human
	int i;
	while(1){
		printf(">>:");
		char line[255]; // input the move to play
		fgets(line, sizeof(line), stdin);
			while(sscanf(line, "%d", &i) != 1) { //1 match of defined specifier on input line
  			printf("Sorry, that's not a valid move!\n");
			fgets(line, sizeof(line), stdin);
		}
		if(s[i-1].value != 0){printf("Sorry, That moves already been taken!\n\n");continue;}
		break;
	}
	s[i-1].value = 1;
	s[i-1].sign = 'x';
	gamestate.moves++;
}

int sum(int x, int y, int z){return(x*y*z);}

void getCompMove(){ // get the move from the computer
	srand(time(NULL)); //seed the time
	int t;
	while(1){
		t = (rand()%9)+1; //temporary
		if(s[t-1].value != 0) continue;
		else break;
	}
	s[t-1].value = 2;
	s[t-1].sign = 'o';
}

void checkWinner(){ // check the winner
	int i;
	for(i = 6; i < 9; i++){ // check cols
		if((sum(s[i].value,s[i-3].value,s[i-6].value)) == 8){printf("The Winner is o!\n");gamestate.state=1;}
		if((sum(s[i].value,s[i-3].value,s[i-6].value)) == 1){printf("The Winner is x!\n");gamestate.state=2;}	
	}
	for(i = 0; i < 7; i+=3){ // check rows
		if((sum(s[i].value,s[i+1].value,s[i+2].value)) == 8){printf("The Winner is o!\n");gamestate.state=1;}
		if((sum(s[i].value,s[i+1].value,s[i+2].value)) == 1){printf("The Winner is x!\n");gamestate.state=2;}
	}
	if((sum(s[0].value,s[4].value,s[8].value)) == 83){printf("The Winner is o!\n");gamestate.state=1;}
	if((sum(s[0].value,s[4].value,s[8].value)) == 1){printf("The Winner is x!\n");gamestate.state=2;}
	if((sum(s[2].value,s[4].value,s[6].value)) == 8){printf("The Winner is o!\n");gamestate.state=1;}
	if((sum(s[2].value,s[4].value,s[6].value)) == 1){printf("The Winner is x!\n");gamestate.state=2;}
}

void playGame(){ // start playing the game
	gamestate.state = 3; //set-up the gamestate
	srand(time(NULL));
	int temp = (rand()%2) + 1;
	if(temp == 2){ // if two comp goes first
		temp = (rand()%2) + 1;
		if(temp == 2){
			s[4].value = 2; s[4].sign = 'o';
			gamestate.moves++;
		}else{
			s[2].value = 2; s[2].sign = 'o';
			gamestate.moves++;
		}
	} 
	displayBoard();
	while(gamestate.state == 3){
	 	if(gamestate.moves==9);
			getHumanMove();
		if(gamestate.moves==9 && gamestate.state ==3)displayBoard();
	    checkWinner();	
		if(gamestate.moves==9);
			getCompMove();
		checkWinner();
		if(gamestate.state == 3 && gamestate.moves==9){
			printf("The game is a tie :p\n");
			break;
		}
		displayBoard();
	}
}

int main(int argc, const char *argv[]){
	printf("Welcome to Tic Tac Toe\nby The Elite Noob\nEnter 1-9 To play a move, standard numpad\n1 is bottom-left, 9 is top-right\n");
	while(1){ // while game is being played
		printf("\nPress 1 to play a new game, or any other number to exit;\n>>:");
		char line[255]; // input whether or not to play the game
		fgets(line, sizeof(line), stdin);
		int choice; // user's choice about playing or not	
		while(sscanf(line, "%d", &choice) != 1) { //1 match of defined specifier on input line
  			printf("Sorry, that's not a valid option!\n");
			fgets(line, sizeof(line), stdin);
		}
		if(choice == 1){
			setUpGame(); // set's up the game
			playGame(); // Play a Game
		}else {break;} // exit the application
	}
	printf("\nThank's For playing!\nHave a good Day!\n");
	return 0;
}