/* Reflow Oven Controller
*
* Copyright (C) 2020  Mario Hüttel <mario.huettel@gmx.net>
*
* This file is part of the Reflow Oven Controller Project.
*
* The reflow oven controller is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* The Reflow Oven Control Firmware is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with the reflow oven controller project.
* If not, see <http://www.gnu.org/licenses/>.
*/

/**
 * @addtogroup safety-controller
 * @{
 */

#include <reflow-controller/safety/safety-controller.h>
#include <reflow-controller/safety/safety-config.h>
#include <reflow-controller/safety/watchdog.h>
#include <reflow-controller/systick.h>

#include <stdbool.h>
#include <stdint.h>
#include <stddef.h>

struct error_flag {
	const char *name;
	enum safety_flag flag;
	bool error_state;
	bool persistent;
};

struct timing_mon {
	const char *name;
	enum timing_monitor monitor;
	uint64_t min_delta;
	uint64_t max_delta;
	uint64_t last;
	bool enabled;
};

struct analog_mon {
	const char *name;
	enum analog_value_monitor monitor;
	float min;
	float max;
	float value;
	bool valid;
};

#ifdef COUNT_OF
#undef COUNT_OF
#endif

#define COUNT_OF(x) ((sizeof(x)/sizeof(0[x])) / ((size_t)(!(sizeof(x) % sizeof(0[x])))))

#define ERR_FLAG_ENTRY(errflag, persistency) {.name=#errflag, .flag = (errflag), .error_state = false, .persistent = (persistency)}
#define TIM_MON_ENTRY(mon, min, max) {.name=#mon, .monitor = (mon), .min_delta = (min), .max_delta = (max), .last = 0ULL, .enabled= false}
#define ANA_MON_ENTRY(mon, min_value, max_value) {.name=#mon, .monitor = (mon), .min = (min_value), .max = (max_value), .value = 0.0f, .valid = false}

static struct error_flag flags[] = {
	ERR_FLAG_ENTRY(ERR_FLAG_MEAS_ADC_OFF, false),
	ERR_FLAG_ENTRY(ERR_FLAG_MEAS_ADC_WATCHDOG, false),
	ERR_FLAG_ENTRY(ERR_FLAG_MEAS_ADC_UNSTABLE, false),
	ERR_FLAG_ENTRY(ERR_FLAG_MEAS_ADC_OVERFLOW, true),
	ERR_FLAG_ENTRY(ERR_FLAG_TIMING_MEAS_ADC, false),
	ERR_FLAG_ENTRY(ERR_FLAG_TIMING_PID, false),
	ERR_FLAG_ENTRY(ERR_FLAG_AMON_UC_TEMP, true),
	ERR_FLAG_ENTRY(ERR_FLAG_AMON_VREF, false),
	ERR_FLAG_ENTRY(ERR_FLAG_STACK, true),
};

static struct timing_mon timings[] = {
	TIM_MON_ENTRY(ERR_TIMING_PID, 1, 800),
	TIM_MON_ENTRY(ERR_TIMING_MEAS_ADC, 1, 50),
	TIM_MON_ENTRY(ERR_TIMING_SAFETY_ADC, 220, 500),
};

static struct analog_mon analog_mons[] = {
	ANA_MON_ENTRY(ERR_AMON_VREF, 2480.0f, 2520.0f),
	ANA_MON_ENTRY(ERR_AMON_UC_TEMP, 0.0f, 55.0f),
};

int safety_controller_report_error(enum safety_flag flag)
{
	uint32_t i;
	int ret = -1;

	for (i = 0; i < COUNT_OF(flags); i++) {
		if (flags[i].flag & flag) {
			flags[i].error_state = true;
			ret = 0;
		}
	}

	return ret;
}

/** @} */

void safety_controller_report_timing(enum timing_monitor monitor)
{
	uint32_t i;
	struct timing_mon *tim;
	uint64_t timestamp;

	timestamp = systick_get_global_tick();

	for (i = 0; i < COUNT_OF(timings); i++) {
		tim = &timings[i];
		if (tim->monitor & monitor) {
			tim->enabled = true;
			tim->last = timestamp;
		}
	}
}

void safety_controller_init()
{
	watchdog_setup(WATCHDOG_PRESCALER);
}

int safety_controller_handle()
{
	int ret = 0;

	/* TODO: Handle safety ADC */

	/* TODO: Check flags for PID and HALT */

	ret |= watchdog_ack(WATCHDOG_MAGIC_KEY);

	return (ret ? -1 : 0);
}

int safety_controller_enable_timing_mon(enum timing_monitor monitor, bool enable)
{
	uint32_t i;
	struct timing_mon *tim;

	if (enable) {
		safety_controller_report_timing(monitor);
	} else {
		for (i = 0; i < COUNT_OF(timings); i++) {
			tim = &timings[i];
			if (tim->monitor & monitor) {
				tim->enabled = false;
			}
		}
	}

	return 0;
}