// SPDX-License-Identifier: GPL-2.0
#include "units.h"
#include "gettext.h"
#include "pref.h"

int get_pressure_units(int mb, const char **units)
{
	int pressure;
	const char *unit;
	const struct units *units_p = get_units();

	switch (units_p->pressure) {
	case BAR:
	default:
		pressure = (mb + 500) / 1000;
		unit = translate("gettextFromC", "bar");
		break;
	case PSI:
		pressure = (int)lrint(mbar_to_PSI(mb));
		unit = translate("gettextFromC", "psi");
		break;
	}
	if (units)
		*units = unit;
	return pressure;
}

double get_temp_units(unsigned int mk, const char **units)
{
	double deg;
	const char *unit;
	const struct units *units_p = get_units();

	if (units_p->temperature == FAHRENHEIT) {
		deg = mkelvin_to_F(mk);
		unit = "°F";
	} else {
		deg = mkelvin_to_C(mk);
		unit = "°C";
	}
	if (units)
		*units = unit;
	return deg;
}

double get_volume_units(unsigned int ml, int *frac, const char **units)
{
	int decimals;
	double vol;
	const char *unit;
	const struct units *units_p = get_units();

	switch (units_p->volume) {
	case LITER:
	default:
		vol = ml / 1000.0;
		unit = translate("gettextFromC", "ℓ");
		decimals = 1;
		break;
	case CUFT:
		vol = ml_to_cuft(ml);
		unit = translate("gettextFromC", "cuft");
		decimals = 2;
		break;
	}
	if (frac)
		*frac = decimals;
	if (units)
		*units = unit;
	return vol;
}

int units_to_sac(double volume)
{
	if (get_units()->volume == CUFT)
		return lrint(cuft_to_l(volume) * 1000.0);
	else
		return lrint(volume * 1000);
}

depth_t units_to_depth(double depth)
{
	depth_t internaldepth;
	if (get_units()->length == METERS) {
		internaldepth.mm = lrint(depth * 1000);
	} else {
		internaldepth.mm = feet_to_mm(depth);
	}
	return internaldepth;
}

double get_depth_units(int mm, int *frac, const char **units)
{
	int decimals;
	double d;
	const char *unit;
	const struct units *units_p = get_units();

	switch (units_p->length) {
	case METERS:
	default:
		d = mm / 1000.0;
		unit = translate("gettextFromC", "m");
		decimals = d < 20;
		break;
	case FEET:
		d = mm_to_feet(mm);
		unit = translate("gettextFromC", "ft");
		decimals = 0;
		break;
	}
	if (frac)
		*frac = decimals;
	if (units)
		*units = unit;
	return d;
}

double get_vertical_speed_units(unsigned int mms, int *frac, const char **units)
{
	double d;
	const char *unit;
	const struct units *units_p = get_units();
	const double time_factor = units_p->vertical_speed_time == MINUTES ? 60.0 : 1.0;

	switch (units_p->length) {
	case METERS:
	default:
		d = mms / 1000.0 * time_factor;
		if (units_p->vertical_speed_time == MINUTES)
			unit = translate("gettextFromC", "m/min");
		else
			unit = translate("gettextFromC", "m/s");
		break;
	case FEET:
		d = mm_to_feet(mms) * time_factor;
		if (units_p->vertical_speed_time == MINUTES)
			unit = translate("gettextFromC", "ft/min");
		else
			unit = translate("gettextFromC", "ft/s");
		break;
	}
	if (frac)
		*frac = d < 10;
	if (units)
		*units = unit;
	return d;
}

double get_weight_units(unsigned int grams, int *frac, const char **units)
{
	int decimals;
	double value;
	const char *unit;
	const struct units *units_p = get_units();

	if (units_p->weight == LBS) {
		value = grams_to_lbs(grams);
		unit = translate("gettextFromC", "lbs");
		decimals = 0;
	} else {
		value = grams / 1000.0;
		unit = translate("gettextFromC", "kg");
		decimals = 1;
	}
	if (frac)
		*frac = decimals;
	if (units)
		*units = unit;
	return value;
}

const struct units *get_units()
{
	return &prefs.units;
}