#include <at89x051.h>

volatile int shot=0;
int refill_size;

volatile int wait_count = 0;
volatile int no_refill = 0;

#define HOPPER_SIZE 180
#define REFILL_SIZE_0 100;
#define REFILL_SIZE_1 110;
#define REFILL_SIZE_2 140;
#define REFILL_SIZE_3 150;

#define HUNDREDS 64
#define TENS 32
#define ONES 16

//This table is a software fix for a hardware problem.  I forgot to re-arange some data bus pins when laying out the PCB
//So the Value for all the pins but A is wrong (so the values are WAY off)
#define USEVALUEMAP 1
 
#ifdef USEVALUEMAP
char value_mapping[10] = {0,1,4,5,8,9,12,13,2,3};
#endif
 
void enable_timer(){
	//stop the timer
	TR0 = 0;

	TH0 = 0; //clear time1
	TL0 = 0;
	TMOD |= T0_M0; //set bit 0
	TMOD &= (~T0_M1); //cleat bit 1
	TF0 = 0;
	
	//and now start the timer
	TR0 = 1;
}

void waitsome(){
	int i;
	for(i = 0;i<255;i++){
		;
	}
}

void selftest(){
	int i=0,j=0;
	
	while(1){
		if(j>9){
			j=0;
		}
		P1 = value_mapping[j] | HUNDREDS | TENS | ONES;
		for(i=0;i<255;i++){
			waitsome();
		}
		j++;
		
	}		
}

void testvalue(int v){
	P1 = value_mapping[v] | HUNDREDS | TENS | ONES;
	PCON = PCON | PD;		
}

void displayshot(){
	int tmp = shot;
	int hundreds;
	int tens;
	int ones;
	
	hundreds = tmp/100;
	tmp -= hundreds*100;
	tens = tmp/10;
	ones = tmp%10;

#ifdef USEVALUEMAP
	//this is a crappy hack to fix a problem I caused when laying out the board.
	hundreds = value_mapping[hundreds];
	tens = value_mapping[tens];
	ones = value_mapping[ones];
#endif
	
	P1= hundreds;
	waitsome();
	P1_6 = 1;
	waitsome();
	P1= hundreds;
	waitsome();

	P1= tens;
	waitsome();
	P1= tens|TENS;
	P1_5 = 1;
	waitsome();
	P1= tens;
	waitsome();

	P1= ones;
	waitsome();
	P1= ones|ONES;
	P1_4 = 1;
	waitsome();
	P1= ones;
	waitsome();

}

volatile void decrement_counter() interrupt 0 {
	if(shot >0){
		shot--;
	}
	displayshot();
	
}


volatile void waitreload_fire() interrupt 1 {
	wait_count++;
	if(P3_3){ 
		if(wait_count >15){
			wait_count = 0;
			if(P3_3){ 
				if( (shot+refill_size) > HOPPER_SIZE){
					shot = HOPPER_SIZE;
				}else{
					shot += refill_size;
				}
				displayshot();
			}	
			TR0 = 0;	//disable the timer
		}	
	}else{
		//the button isn't pressed, disable the timer
		TR0 = 0;
		wait_count = 0;
	}
}

volatile void refill() interrupt 2 {
	enable_timer();
}



int main(){	
	//setup the shot counter
	P0=0;
	shot=HOPPER_SIZE; 
	displayshot();
	
	//setup interrupt handling 
	IT0 = 1; //edge trigger INT0
	IT1 = 1; //edge trigger INT1
	EX0 = 1; //Enable INT0
	EX1 = 1; //Enable INT1
	ET0 = 1; //Enable Timer0
	EA  = 1; //enable interrupts
	
	//TODO: set this based on the inputs for size.
	refill_size = REFILL_SIZE_0;
		
	//go to idle mode, wait for interrupts to do anything
	while(1){
		PCON |= IDL;
	}
	//return 0;
}