#include "circsim.h"

#include <string.h>

static const int gateL[9] = { 0, 2, 1, 1, 0, 2, 2, 1, 0 };
static const int gateR[9] = { 2, 2, 2, 2, 0, 1, 2, 1, 0 };

void circsim(int gates, int *gatepins, int *states, int streamlen, int *stream) {
	for (; streamlen-- > 0; stream++) {
		int i;
		states[0] = *stream;
		for (i = 0; i < gates; i++) {
			int k = 3*states[gatepins[2*i+1]] + states[gatepins[2*i+2]];
			states[2*i+1] = gateL[k];
			states[2*i+2] = gateR[k];
		}
		*stream = states[gatepins[0]];
	}
}

int findcirc(int gates, int *gatepins, int streamlen, int *stream, int *output) {
	int states[2*gates+1];
	memset(states, 0, sizeof(int) * (2*gates+1));
	for (; streamlen-- > 0; stream++) {
		int i;
		states[0] = *stream;
		for (i = 0; i < gates; i++) {
			int k = 3*states[gatepins[2*i+1]] + states[gatepins[2*i+2]];
			states[2*i+1] = gateL[k];
			states[2*i+2] = gateR[k];
		}
		if (*output++ != states[gatepins[0]]) return 0;
	}
	return 1;
}