#include <tigcclib.h>
#define LCD_BYTES_COLS		20
#define LCD_ROW_BYTES			30
#define LCD_BOTTOM_ROW 		(void *)0x579A
#define ARROW_ROW					0xFFFE
#define ESCROW 0xFFBF  // the ESC row on the TI-89 keyboard matrix
#define ESCKEY 0x0001  // the ESC key inside that row

enum ArrowKeys {UP,DOWN,LEFT,RIGHT};

unsigned long blocks = 0;
char spacing_count = 38, max_spacing = 40, max_spacing_count = 0, platform_row = 4;

unsigned char ball_x = 77, ball_y = 50;
unsigned char ball[] = {0x78,0x9C,0xBC,0xFC,0xFC,0x78};

void delay(int len) {
	int i, randnum;
	for (i = 0; i < len; i++) {
		randnum = random(0xFF);
	}
}

void scroll_up() {
	memcpy(LCD_MEM, LCD_MEM + LCD_ROW_BYTES, LCD_ROW_BYTES * LCD_HEIGHT);
}

void draw_platform() {
	if (platform_row == 4) {   // If we have drawn all four lines of a platform
		spacing_count++;  // Increase our count of the space between each platform
		if (spacing_count == max_spacing) {  // If it is time to draw a new block...
			platform_row = 0;
			randomize();
			blocks = ((long)random(0xFFFF) << 16) | ((long)random(0xFFFF));  // Generate a new random platform 
			spacing_count = 0;   // Reset the spacing count
			max_spacing_count++;  // And add one to max spacing count
			if (max_spacing_count == 6) {   // Its time to decrease the spacing between platforms
				max_spacing -= 2; 
				if (max_spacing <= 8) {  // Unless the spacing is too thin, then dont change it
					max_spacing = 8;
				} 
				max_spacing_count = 0;
			}
		}
	} else {
		int i;
		unsigned long bits = 0x00080000;
		char *lcd = LCD_BOTTOM_ROW;
		for (i = 0; i < 20; i++){
			if (blocks & bits) {
				if (platform_row == 0 || platform_row == 3) {
					lcd[i] = 0xFF;  // Fill ones with lines
				} else {
					lcd[i] = random(0xFF);  // or with randomness
				}
			}
			bits >>= 1;
		}
		platform_row++;
	}
}

void move_up() {
	ball_y--; 
}

void move_down() {
	Sprite8(ball_x, ball_y - 1, 6, ball, LCD_MEM, SPRT_XOR);
	if (ball_y < 94) {
		ball_y++;
	}
	Sprite8(ball_x, ball_y, 6, ball, LCD_MEM, SPRT_XOR);	
}

void move_left() {
	Sprite8(ball_x, ball_y, 6, ball, LCD_MEM, SPRT_XOR);
	ball_x--;
	Sprite8(ball_x, ball_y, 6, ball, LCD_MEM, SPRT_XOR);
}

void move_right() {
	Sprite8(ball_x, ball_y, 6, ball, LCD_MEM, SPRT_XOR);
	ball_x++;
	Sprite8(ball_x, ball_y, 6, ball, LCD_MEM, SPRT_XOR);
}

void move_ball() {
	// Gravitty
	unsigned char *check = LCD_MEM + (LCD_ROW_BYTES * (ball_y + 5)) + (ball_x / 8);
//	*check = 0x02;
	if (ball_x % 8 < 3) {
		if (!*check) { 
			move_down();
		} else {
			move_up();
		}
	} else {
		if (!(check[0] | check[1])) {
			move_down();
		} else {
			move_up();
		}
	}
	int keys[4], key;
	keys[0] = 0x0001;   // bit 0
	keys[1] = 0x0004;   // bit 2
	keys[2] = 0x0002;   // bit 1
	keys[3] = 0x0008;   // bit 3
	
	//Left and right
	key = _rowread(ARROW_ROW);
	
	if (key & keys[LEFT]) {
		move_left();
	}

	if (key & keys[RIGHT]) {
		move_right();
	}
}

void _main(void) {
	ClrScr();
//	for (i = 0; i < 100; i++) {
//		scroll_up();
//	}
	Sprite8(ball_x, ball_y, 6, ball, LCD_MEM, SPRT_XOR);
//	unsigned char *check = 0x550F;
//	*check = 0x02;

	INT_HANDLER interrupt1 = GetIntVec(AUTO_INT_1); // save auto-interrupt 1
	INT_HANDLER interrupt5 = GetIntVec(AUTO_INT_5); // save auto-interrupt 5
	SetIntVec(AUTO_INT_1,DUMMY_HANDLER);
	SetIntVec(AUTO_INT_5,DUMMY_HANDLER);
   
	int i;
//	for (i = 0; i < 150; i++) {
	while (!(_rowread(ESCROW) & ESCKEY)) {
		scroll_up();
		draw_platform();
		move_ball();
		if (ball_y == 0) { DrawStr(0, 50, "LOSER", A_NORMAL); i = 150; }
		delay(500);
	}
	
	SetIntVec(AUTO_INT_1,interrupt1);
	SetIntVec(AUTO_INT_5,interrupt5);
	

	ngetchx();
}