#include <libps.h>
#include <rand.h>
#include "MyPad.h"
#include "Sin.h"
#include "Cos.h"

#define OT_LENGTH		2
#define PACKETMAX		2048
#define PACKETMAX2		(PACKETMAX*24) 
#define ANIM_ADDRESS	0x80090000
#define SHIP_ADDRESS	0x800a8014
#define BALL_ADDRESS	0x800aa028

typedef struct {
	long x, y, vx, vy;
	int ang;
	u_char weapons;
	u_char health;
} Ship;

typedef struct {
	long x, y, vx, vy;
	u_char countDown, connected;
} Ball;

typedef struct {
	int x[256], y[256], vx[256], vy[256];
	u_char age[256];
	int first, last;
} Particle;

GsOT		WorldOT[2];	
GsOT_TAG	OTTags[2][1<<OT_LENGTH];
static PACKET packetArea[2][PACKETMAX2];
volatile u_char *bb0, *bb1;
GsIMAGE shipImage;
GsIMAGE ballImage;

// u, v co-ordinates in frame buffer for ship animation
u_char u[24] = {	0,0,64,128,192,0,
					64,128,192,0,64,128,
					192,128,64,0,192,128,
					64,0,192,128,64,0
				};

u_char v[24] = {	192,0,0,0,0,64,
					64,64,64,128,128,128,
					128,128,128,128,64,64,
					64,64,0,0,0,0
				};

int main(void);
void ProperInitialiseTexture(long TIMdata, GsIMAGE *imageInfo);
void InitGame(void);
int IntSqrt(register int n);
static u_long ReadPad(void);

int main(void) {
	int activeBuff, frame=0, i;
	long dis, dx, dy, force;
	GsSPRITE shipSprite, ballSprite;
	Ship ship;
	Ball ball;
	Particle thrust;
	GsBOXF box;
	u_long pad;

	InitGame();
	
	ProperInitialiseTexture(SHIP_ADDRESS, &shipImage);
	ProperInitialiseTexture(ANIM_ADDRESS, &shipImage);
	ProperInitialiseTexture(BALL_ADDRESS, &ballImage);

	shipSprite.attribute = (1<<25);
	shipSprite.w = 64;
	shipSprite.h = 64;
	shipSprite.r = 128;
	shipSprite.g = 128;
	shipSprite.b = 128;
	shipSprite.mx = 32;
	shipSprite.my = 32;
	shipSprite.scalex = ONE;
	shipSprite.scaley = ONE;
	shipSprite.rotate = 0;
	shipSprite.tpage = GetTPage(2, 0, shipImage.px, shipImage.py);
	
	ballSprite.attribute = (1<<25);
	ballSprite.v = 192;
	ballSprite.w = 48;
	ballSprite.h = 48;
	ballSprite.r = 128;
	ballSprite.g = 128;
	ballSprite.b = 128;
	ballSprite.mx = 24;
	ballSprite.my = 24;
	ballSprite.scalex = ONE;
	ballSprite.scaley = ONE;
	ballSprite.rotate = 0;
	ballSprite.tpage = GetTPage(2, 0, shipImage.px, shipImage.py);

	ship.x = 320<<12;
	ship.y = 256<<12;
	ship.vx = 0;
	ship.vy = 0;
	ship.ang = 0;
	
	ball.x = 320<<12;
	ball.y = 320<<12;
	ball.vx = 0;
	ball.vy = 0;
	ball.connected = 1;
	
	thrust.first = 0;
	thrust.last = 0;
	
	box.w = 2;
	box.h = 2;
	box.attribute = 0;
	box.r = 255;
	box.g = 0;
	box.b = 0;
	
	do {
		pad = ReadPad();
		
		activeBuff = GsGetActiveBuff();
		GsSetWorkBase((PACKET *)packetArea[activeBuff]);
		GsClearOt(0, 0, &WorldOT[activeBuff]);
		if (pad & PADLleft)
			ship.ang -= 4;
		if (pad & PADLright)
			ship.ang += 4;

		if (ship.ang > 359)
			ship.ang -= 360;
		else {
			if (ship.ang < 0)
				ship.ang += 360;
		}

		if (pad & PADLX) {
			ship.vx += intSin[ship.ang];
			ship.vy -= intCos[ship.ang];
			for (i=0; i<1; i++) {
				thrust.x[thrust.last & 255] = ship.x-intSin[ship.ang]*32;
				thrust.y[thrust.last & 255] = ship.y+intCos[ship.ang]*32;
				thrust.vx[thrust.last & 255] = (rand() & 4095)-intSin[ship.ang]-2048;
				thrust.vy[thrust.last & 255] = (rand() & 4095)+intCos[ship.ang]-2048;
				thrust.age[thrust.last & 255] = 31;
				thrust.last++;
			}
		}
		
		dx = (ship.x-ball.x)>>6;
		dy = (ship.y-ball.y)>>6;
		
		dis = IntSqrt(dx*dx+dy*dy);
		force = dis-4096;
		if (force<0)
			force = 0;
		if (dis<1)
			dis = 1;
		ball.vx += force*dx/dis;
		ball.vy += force*dy/dis;
		ship.vx -= force*dx/dis;
		ship.vy -= force*dy/dis;
		ball.x += ball.vx;
		ball.y += ball.vy;
		ball.vx = (ball.vx*15)>>4;
		ball.vy = ((ball.vy+2048)*15)>>4;

		shipSprite.u = u[frame];
		shipSprite.v = v[frame++];
		shipSprite.x = ship.x>>12;
		shipSprite.y = ship.y>>12;
		shipSprite.rotate = ship.ang<<12;
		
		ship.y += ship.vy>>1;
		ship.x += ship.vx>>1;
		
		if (ship.y>510<<12 || ship.y<0) {
			ship.y -= ship.vy>>1;
			ship.vy = -ship.vy>>1;
		}
		if (ship.x>639<<12 || ship.x<0) {
			ship.x -= ship.vx>>1;
			ship.vx = -ship.vx>>1;
		}
		ship.vy += 512;
		
		for (i=thrust.first; i<thrust.last; i++) {
			box.x = (short )(thrust.x[i & 255]>>12);
			box.y = (short )(thrust.y[i & 255]>>12);
			box.g = thrust.age[i & 255]<<3;
			thrust.x[i & 255] += thrust.vx[i & 255]<<2;
			thrust.y[i & 255] += thrust.vy[i & 255]<<2;
			thrust.age[i & 255]--;
			if (thrust.age[i & 255] == 0)
				thrust.first++;
			GsSortBoxFill(&box, &WorldOT[activeBuff], 1);
		}
		
		GsSortSprite(&shipSprite, &WorldOT[activeBuff], 0);
		
		ballSprite.u = ((frame>>1) & 3)*48 + 64;
		ballSprite.x = ball.x>>12;
		ballSprite.y = ball.y>>12;
		GsSortSprite(&ballSprite, &WorldOT[activeBuff], 0);
		
		if (frame==13)
			shipSprite.scalex = -ONE;
		if (frame==24) {
			frame = 0;
			shipSprite.scalex = ONE;
		}
		
		VSync(0);
		ResetGraph(1);
		GsSwapDispBuff();
		
		GsDrawOt(&WorldOT[activeBuff]);
	} while ((pad & PADLselect) == 0);
	return(0);
}


void ProperInitialiseTexture(long TIMdata, GsIMAGE *imageInfo) {
	RECT rect;

	GsGetTimInfo((u_long *)(TIMdata+4), imageInfo);

	rect.x = imageInfo->px;
	rect.y = imageInfo->py;
	rect.w = imageInfo->pw;
	rect.h = imageInfo->ph;
	
	LoadImage(&rect, imageInfo->pixel);

	if ((imageInfo->pmode>>3) & 0x01) {
		rect.x = imageInfo->cx;	
		rect.y = imageInfo->cy;	
		rect.w = imageInfo->cw;	
		rect.h = imageInfo->ch;	

		LoadImage(&rect, imageInfo->clut);
	}

	DrawSync(0);
}


void InitGame(void) {
	int i;
	
	SetVideoMode(MODE_PAL);
	GsInitGraph(640, 512, 5, 1, 0);
	GsDISPENV.screen.h = 255;
	GsDISPENV.screen.y = 16;
	
	GsDRAWENV.isbg = 1;
	GsDRAWENV.r0 = 0;
	GsDRAWENV.g0 = 0;
	GsDRAWENV.b0 = 0;
	
	GetPadBuf(&bb0, &bb1);
	
	for (i = 0; i < 2; i++) {
		WorldOT[i].length = OT_LENGTH;
		WorldOT[i].org = OTTags[i];
	}
	GsClearOt(0,0,&WorldOT[0]);
	GsClearOt(0,0,&WorldOT[1]);
}


int IntSqrt(register int n) {
	register int i;
	register long k0, k1, nn;

	for (nn = i = n, k0 = 2; i > 0; i >>= 2, k0 <<= 1)
		;
	
	nn <<= 2;
	for (;;) {
		k1 = (nn / k0 + k0) >> 1;
		if (((k0 ^ k1) & ~1) == 0)
			break;
		k0 = k1;
	}
	return (int )((k1 + 1) >> 1);
}


u_long ReadPad(void) {
	return(~(*(bb0+3) | *(bb0+2) << 8 | *(bb1+3) << 16 | *(bb1+2) << 24));
}