#include <msp430.h> 

/*
 * Developer - Samarth Artweaver
 * Date - 28/5/2012
 *
 * pin configuration -
 *
 * p1.0 - switch1
 * p1.1 - switch2
 * p1.2 - switch3
 * p1.3 - switch4
 * p1.4 - latch clock
 * p1.5 - shift clock
 * p2.0 - switch5
 * p2.1 - switch6
 * p2.2 - switch7
 *
 * p1.7 - data output
 *
 */

void delay(int);
void initialize();
void send(int, int);
void sendij(int,int);
void set_display();
void compute_ball();
void check_game();
void check_game2();
void game_over(int);
void startup_screen();
void display(int);

int i=3,j=3,level=100; //level = speed
int p1[5]={2,3,4};     //player 1 pixels
int p2[5]={2,3,4};	   //player 2 pixels
int ver=0,hor=0,a,b,paus=0;
/*ver = 0 => moving left  = 1 => moving right
 *hor = 0 => moving down  = 1 => moving up
*/
int scorea=4,scoreb=4; //initial scores of the players

int arr2[7][8]=
{
		{0x00,0x3c,0x24,0x24,0x24,0x24,0x3c,0x00},//0
		{0x00,0x10,0x30,0x50,0x10,0x10,0x10,0x7c},//1
		{0x00,0x38,0x44,0x04,0x08,0x10,0x7c,0x00},//2
		{0x00,0x38,0x04,0x04,0x18,0x04,0x04,0x38},//3
		{0x00,0x24,0x24,0x24,0x3c,0x04,0x04,0x04},//4
		{0x00,0x10,0x28,0x44,0x44,0x7c,0x44,0x44},//a
		{0x00,0x38,0x24,0x24,0x38,0x24,0x24,0x38},//b
};


void main(void) {

	initialize(); 		//the serial communication, interrupts, IO pins, etc

	startup_screen(); 	// P I N G P O N G  display

	while(1)
	{

		compute_ball(); //compute ball's next state

		set_display(); 	//display ball and the players

		if(j==6)
		check_game();	//check game for player 1

		if(j==1)
		check_game2();	//check game for player2
	}
}

void startup_screen()
{
	int arr[8][8]=
		{{0x00,0x3c,0x24,0x24,0x3c,0x20,0x20,0x00},//p
		{0x00,0x7c,0x10,0x10,0x10,0x10,0x7c,0x00},//i
		{0x00,0x44,0x64,0x54,0x4c,0x44,0x44,0x00},//n
		{0x00,0x3c,0x20,0x20,0x2c,0x24,0x3c,0x00},//g
		{0x00,0x3c,0x24,0x24,0x24,0x24,0x3c,0x00}};//o

	int seq[8]={0,1,2,3,0,4,2,3}; //PINGPONG

	int c;

	for(a=0;a<8;a++)
	{
		for(c=0;c<100;c++)
		{
			for(b=0;b<8;b++)
			{
					send(1<<b,arr[seq[a]][b]); //send pingpong
					delay(1);
			}
		}
	}

	paus=1;  //pause the game
}



void set_display()
{
	do
	{
		for(b=0; b<level; b++)
		{
			sendij(i,j);			//display ball

			for(a=0;a<3;a++)
				sendij(p1[a],7);	//display player 1

			for(a=0;a<3;a++)
				sendij(p2[a],0);	//display player 2
		}
	}
	while(paus); 					//see if to give a pause
}

void compute_ball()
{
	if(ver==0) 	//going left
		j++;
	else		//going right
		j--;
	if(hor==0) 	//going down
		i++;
	else		//going up
		i--;


	if(i==0)
		hor=0;
	else if(i>=7)
		hor=1;
	if(j==1)
		ver=0;
	else if(j>=6)
		ver=1;
}

void check_game()
{
	for(a=0;a<3;a++)
	{
		if(p1[a]==i)
			break;
	}
	if(a==1)
	{
		if(i>0 && hor==0) hor=1;
		else if(i<7 && hor==1) hor=0;
	}
	if(hor==0 && p1[0]==(i+1))
	{
		a=0;
		if(i>0) hor=1;
	}
	if(hor==1 && p1[2]==(i-1))
	{
		a=0;
		if(i<7)	hor=0;
	}

	if(a==3)
	{
		game_over(1);
		scorea--;
	}
}

void check_game2()
{
	for (a = 0; a < 3; a++)
	{
		if (p2[a] == i)
			break;
	}

	if (a == 1)
	{
		if (i > 0 && hor == 0)
			hor = 1;
		else if (i < 7 && hor == 1)
			hor = 0;
	}

	if(hor==0 && p2[0]==(i+1))
	{
		a=0;
		if(i>0) hor=1;
	}
	if(hor==1 && p2[2]==(i-1))
	{
		a=0;
		if(i<7)	hor=0;
	}

	if (a == 3)
	{
		game_over(2);
		scoreb--;
	}
}


void game_over(int x)
{
	if(x==1)
	{
		if(scorea!=0)
			display(scorea);
		else
		{
			display(6);
		}
	}
	else
	{
		if(scoreb!=0)
			display(scoreb);
		else
		{
			display(5);
		}
	}
}

void display(int x)
{
	int c;

	for(c=0;c<300;c++)
	{
		for(a=0;a<8;a++)
		{
				send(1<<a,arr2[x][a]);
				delay(1);
		}
	}

	if(x==5 || x==6) 			WDTCTL = 0;

}

#pragma vector=PORT1_VECTOR
__interrupt void Port_1(void) {
	int a;
	if(P1IFG & 0x04)
	{
		for(a=0;a<3;a++)
		{
			p1[a]--;
			if(p1[a]==-1) p1[a]=7;
		}
	}
	else if(P1IFG & 0x02)
	{
		for(a=0;a<3;a++)
		{
			p1[a]++;
			if(p1[a]==8) p1[a]=0;
		}
	}
	else if(P1IFG & 0x01)
	{
		if(paus==0) paus=1;
		else paus =0;
	}
	else if(P1IFG & 0x08)
	{
		if(level==100) level=60;
		else if(level==60) level=30;
		else level=100;
	}
	P1IFG &= ~(BIT0 + BIT1 + BIT2 + BIT3); //flag cleared
}


#pragma vector=PORT2_VECTOR
__interrupt void Port_2(void)
{
	int a;
	if(P2IFG & 0x01)
	{
		for(a=0;a<3;a++)
		{
			p2[a]--;
			if(p2[a]==-1) p2[a]=7;
		}
	}
	else if(P2IFG & 0x02)
	{
		for(a=0;a<3;a++)
		{
			p2[a]++;
			if(p2[a]==8) p2[a]=0;
		}
	}
	else if(P2IFG & 0x04)
	{

	}
	else if(P2IFG & 0x08)
	{

	}

	P2IFG &= ~(BIT0 + BIT1 + BIT2); //flag cleared
}

void sendij(int i,int j)
{
	send(1<<i,1<<j);
	delay(1);
	send(0,0);
}

void delay(int i)
   {
   	for(;i>0;i--)
   	_delay_cycles(10000);
   }

void initialize()
{
    /* Stop watchdog timer from timing out during initial start-up. */
    WDTCTL = WDTPW | WDTHOLD;

    P1SEL2 = BIT5 + BIT6 + BIT7;

   P1OUT = 0;

    /* Port 1 Port Select Register */
    P1SEL = BIT5 + BIT6 + BIT7;

    /* Port 1 Direction Register */
    P1DIR = BIT4;

    /* Port 1 Interrupt Edge Select Register */
    P1IES = 0;

    /* Port 1 Interrupt Flag Register */
    P1IFG = 0;

    /* Port 2 Output Register */
    P2OUT = 0;

    /* Port 2 Direction Register */
    P2DIR = 0;

    /* Port 2 Interrupt Edge Select Register */
    P2IES = 0;

    /* Port 2 Interrupt Flag Register */
    P2IFG = 0;


    BCSCTL2 = SELM_0 + DIVM_0 + DIVS_0;

    if (CALBC1_16MHZ != 0xFF) {
        /* Adjust this accordingly to your VCC rise time */
        __delay_cycles(100000);

        /* Follow recommended flow. First, clear all DCOx and MODx bits. Then
         * apply new RSELx values. Finally, apply new DCOx and MODx bit values.
         */
        DCOCTL = 0x00;
        BCSCTL1 = CALBC1_16MHZ;     /* Set DCO to 16MHz */
        DCOCTL = CALDCO_16MHZ;
    }

    BCSCTL1 |= XT2OFF + DIVA_0;

    BCSCTL3 = XT2S_0 + LFXT1S_2 + XCAP_1;

    UCB0CTL1 |= UCSWRST;
    UCB0CTL0 = UCCKPH + UCMST + UCMODE_0 + UCSYNC;
    UCB0CTL1 = UCSSEL_2 + UCSWRST;
    UCB0CTL1 &= ~UCSWRST;

   __bis_SR_register(GIE);

   WDTCTL = WDTPW + WDTHOLD;


   //interupt buttons

	P1REN |= BIT0 + BIT1 + BIT2 + BIT3; // P1.3 Enable Pullup/Pulldown
	P1OUT = BIT0 + BIT1 + BIT2 + BIT3; // P1.3 pullup
	P1IE |= BIT0 + BIT1 + BIT2 + BIT3; // P1.3 interrupt enabled
	P1IES |= BIT0 + BIT1 + BIT2 + BIT3; // P1.3 Hi/lo falling edge
	P1IFG &= ~(BIT0 + BIT1 + BIT2 + BIT3); // P1.3 IFG cleared just in case

	P2REN |= BIT0 + BIT1 + BIT2; // P1.3 Enable Pullup/Pulldown
	P2OUT = BIT0 + BIT1 + BIT2; // P1.3 pullup
	P2IE |= BIT0 + BIT1 + BIT2; // P1.3 interrupt enabled
	P2IES |= BIT0 + BIT1 + BIT2; // P1.3 Hi/lo falling edge
	P2IFG &= ~(BIT0 + BIT1 + BIT2); // P1.3 IFG cleared just in case

	_EINT();

}

void send(int i, int j)
{
	P1OUT &= ~BIT4;
	UCB0TXBUF = i;
	P1OUT |= BIT4 ;

	P1OUT &= ~BIT4;
	UCB0TXBUF = j;
	P1OUT |= BIT4 ;
}