#include <stdio.h>
#include <sys/types.h>
#include <sys/sysctl.h>

#define max(a,b) (a < b) ? b : a
void tempmon(int target, int crit);

int main(void)
{
	const int temp_target = 55, temp_crit = 80;

	while (1) {
		tempmon(temp_target, temp_crit);
		sleep(1);
	}

	return (0);
}

void tempmon(int target, int crit)
{
	int tempa, tempb, maxtemp, i;
	size_t temp_size = sizeof(tempa);
	const char *fans[] = {"backside", "cpu_a_intake", "cpu_b_intake",
	    "cpu_a_exhaust", "cpu_b_exhaust", NULL};
	double factor;

	sysctlbyname("dev.smusat.0.cpu_a0_diode_temp", &tempa, &temp_size,
	    NULL, 0);
	sysctlbyname("dev.smusat.0.cpu_a1_diode_temp", &tempb, &temp_size,
	    NULL, 0);

	printf("Temps: %d/%d\n", tempa, tempb);
	maxtemp = max(tempa, tempb);
	factor = (double)(maxtemp - target) / (double)(crit - target);
	printf("Fractional Excess: %lf\n", factor);

	if (factor < 0)
		factor = 0;

	for (i = 0; fans[i] != NULL; i++) {
		const char *fan;
		char sysctlname[64];
		int fanmin, fanmax, fanrpm;

		fan = fans[i];

		sprintf(sysctlname, "dev.smu.0.fans.%s.minrpm", fan);
		sysctlbyname(sysctlname, &fanmin, &temp_size, NULL, 0);
		sprintf(sysctlname, "dev.smu.0.fans.%s.maxrpm", fan);
		sysctlbyname(sysctlname, &fanmax, &temp_size, NULL, 0);

		fanrpm = factor*(fanmax - fanmin) + fanmin;
		printf("Setting fan %s to %d RPM\n", fan, fanrpm);

		sprintf(sysctlname, "dev.smu.0.fans.%s.rpm", fan);
		sysctlbyname(sysctlname, NULL, NULL, &fanrpm, temp_size);
	}
}