/**********************************************************\
* Rocks : a bit-mapped arcade game for the AT&T UNIX PC.   *
*                                                          *
* By : Hans Jespersen                                      *
*                                                          *
\**********************************************************/

#include "rocks.h"

movedebris()
{
	int i;

	for( i = 0; i < 3; i++){
	
		/* 
		 * move debris
		 */
	
		debrislist[i].x += debrislist[i].xdelta;
		debrislist[i].y += debrislist[i].ydelta;	
	
		/* 
		 * check for wrap around 
		 */
	
		if ( debrislist[i].x > SCREEN_WIDTH - SHIP_WIDTH )
			debrislist[i].x = 0;
		else if ( debrislist[i].x < 0 )
			debrislist[i].x = SCREEN_WIDTH - SHIP_WIDTH;
		if ( debrislist[i].y > SCREEN_HEIGHT - SHIP_HEIGHT )
			debrislist[i].y = 0;
		else if ( debrislist[i].y < 0 )
			debrislist[i].y = SCREEN_HEIGHT - SHIP_HEIGHT;
	
		/*
		 * place debris in new position 
		 */
	
		wrastop(wn,debris[i],2,screen,WIDTH,0,0,debrislist[i].x,debrislist[i].y,SHIP_WIDTH,SHIP_HEIGHT,SRCSRC,DSTOR,0);
	}
}

moveship()
{

	/* 
	 * move ship
	 */

	myship.x += myship.xdelta;
	myship.y += myship.ydelta;	

	/* 
	 * check for wrap around 
	 */

	if ( myship.x > SCREEN_WIDTH - SHIP_WIDTH )
		myship.x = 0;
	else if ( myship.x < 0 )
		myship.x = SCREEN_WIDTH - SHIP_WIDTH;
	if ( myship.y > SCREEN_HEIGHT - SHIP_HEIGHT )
		myship.y = 0;
	else if ( myship.y < 0 )
		myship.y = SCREEN_HEIGHT - SHIP_HEIGHT;

	/*
	 * place ship in new position 
	 */

	wrastop(wn,ship[direction],2,screen,WIDTH,0,0,myship.x,myship.y,SHIP_WIDTH,SHIP_HEIGHT,SRCSRC,DSTOR,0);
}

moverocks()
{
	int i;

	/*
	 * erase screen bitmap
	 */

	wrastop(wn,0,0,screen,WIDTH,0,0,0,0,SCREEN_WIDTH,SCREEN_HEIGHT+LARGE_ROCK_HEIGHT,SRCPAT,DSTSRC,0);

	/*
	 * move each rock one at a time
	 */

	for ( i = 0; i < nrocks; i++ ){

		/* move rock to new location */ 

		rocklist[i].x += rocklist[i].xdelta; 
		rocklist[i].y += rocklist[i].ydelta; 

		/* check for wrap around */

		if ( rocklist[i].x > SCREEN_WIDTH )
			rocklist[i].x = 0;
		else if ( rocklist[i].x < 0 )
			rocklist[i].x = SCREEN_WIDTH;
		if ( rocklist[i].y > SCREEN_HEIGHT )
			rocklist[i].y = 0;
		else if ( rocklist[i].y < 0 )
			rocklist[i].y = SCREEN_HEIGHT; 

		/* put rock in new location */

		wrastop(wn,rock[rocklist[i].size],8,screen,WIDTH,0,0,rocklist[i].x,rocklist[i].y,rockwidth[ rocklist[i].size ],rockheight[ rocklist[i].size ],SRCSRC,DSTOR,0);
	}
}

moveshots()
{
	int i,j,splitflag = FALSE;
	
	/*
	 * move shots one at a time
 	 */

	for ( i = 0; i <= nshots; i++ ){

		/* move shot */

		shotlist[i].x += shotlist[i].xdelta;
		shotlist[i].y += shotlist[i].ydelta;

		/* wrap around */

		if ( shotlist[i].x >= SCREEN_WIDTH )
			shotlist[i].x = 0;
		else if ( shotlist[i].x < 0 )
			shotlist[i].x = SCREEN_WIDTH - 1;
		if ( shotlist[i].y >= SCREEN_HEIGHT )
			shotlist[i].y = 0;
		else if ( shotlist[i].y < 0 )
			shotlist[i].y = SCREEN_HEIGHT - 1; 

		/* print new shot */

		point(shotlist[i].x, shotlist[i].y);

		/* check for collisions between each rock and each shot */

		for ( j = 0; (j <= nrocks) && (splitflag == FALSE); j++ ){
			if( collide( shotlist[i], 1, 1, rocklist[j], rockwidth[rocklist[j].size], rockheight[rocklist[j].size ]) ){
	
				/* erase shot */

				point(shotlist[i].x, shotlist[i].y);
		
				/* remove shot from shotlist */

				removeshot( i );

				/* update score */ 

				score += (3 - rocklist[j].size ) * 100;
				printscore();

				/* split rock into smaller units */

				split_rock( j );
				splitflag = TRUE;
			}
		}
		
		/* reduce range of shot by one */

		shotlist[i].size -= 1;

		/* if shot has worn out erase it */

		if ( shotlist[i].size == 0 ){
			point(shotlist[i].x, shotlist[i].y);
			removeshot( i );
		}
	}
}

split_rock( index )
int index;
{
	int i;

	wrastop(wn,rock[rocklist[index].size],8,screen,WIDTH,0,0,rocklist[index].x,rocklist[index].y,rockwidth[ rocklist[index].size ], rockheight[ rocklist[index].size ],SRCSRC,DSTCAM,0);
	 if ( rocklist[index].size != SMALL ){
		for ( i = 0; i < 2; i++ ){
			rocklist[nrocks+i].x = rocklist[ index ].x + ( rockwidth[ rocklist[ index ].size ] / 2 );
			rocklist[nrocks+i].y = rocklist[ index ].y + ( rockheight[ rocklist[ index ].size ] / 2 );
			rocklist[nrocks+i].xdelta = randdir() * ((rand()%4)+(3-rocklist[nrocks+i].size));
			rocklist[nrocks+i].ydelta = randdir() * ((rand()%4)+(3-rocklist[nrocks+i].size));
			rocklist[nrocks+i].size = rocklist[ index ].size - 1;
		}
		nrocks += 2;
	}
	removerock( index );	
	if( nrocks == 0 )
		quitflag = TRUE;
}

removerock( index )
int index;
{
	int i;

	for( i = index; i < nrocks; i++ )
		rocklist[ i ] = rocklist[ i + 1 ];
	nrocks -= 1;
}

removeshot( index )
int index;
{
	int i;

	for( i = index; i < nshots; i++ )
		shotlist[ i ] = shotlist[ i + 1 ];
	nshots -= 1;
}

printscreen()
{
	wrastop(wn,screen,WIDTH,screen,WIDTH,0,SCREEN_HEIGHT,0,0,SCREEN_WIDTH,LARGE_ROCK_HEIGHT,SRCSRC,DSTOR,0);
	wrastop(wn,screen,WIDTH,0,0,0,0,0,0,SCREEN_WIDTH,SCREEN_HEIGHT,SRCSRC,DSTSRC,0);
}

clearscreen()
{
	wrastop(wn,screen,WIDTH,screen,WIDTH,0,0,0,0,SCREEN_WIDTH,SPACE_HEIGHT,SRCSRC,DSTCAM,0);
}

thrust()
{
	switch ( direction ) {
	case	0:	myship.ydelta -= 1;
			break;
	case	1:	myship.xdelta += 1;
			myship.ydelta -= 1;
			break;
	case	2:	myship.xdelta += 1;
			break;
	case	3:	myship.xdelta += 1;
			myship.ydelta += 1;
			break;
	case	4:	myship.ydelta += 1;	
			break;
	case	5:	myship.xdelta -= 1;
			myship.ydelta += 1;
			break;
	case 	6:	myship.xdelta -= 1;
			break;
	case 	7:	myship.xdelta -= 1;
			myship.ydelta -= 1;
			break;
	}
	if( myship.xdelta > MAXTHRUST )
		myship.xdelta = MAXTHRUST;
	else if( myship.xdelta < (-1 * MAXTHRUST ) )
		myship.xdelta = -1 * MAXTHRUST;
	if( myship.ydelta > MAXTHRUST )
		myship.ydelta = MAXTHRUST;
	else if( myship.ydelta < (-1 * MAXTHRUST ) )
		myship.ydelta = -1 * MAXTHRUST;
}

hyperspace() 
{
	myship.x = rand() % SCREEN_WIDTH;
	myship.y = rand() % SCREEN_HEIGHT;
	myship.xdelta = 0;
	myship.ydelta = 0;
}