// SPDX-License-Identifier: GPL-2.0-only
/*
 * Thermal monitoring tool based on the thermal netlink events.
 *
 * Copyright (C) 2022 Linaro Ltd.
 *
 * Author: Daniel Lezcano <daniel.lezcano@kernel.org>
 */
#include <errno.h>
#include <fcntl.h>
#include <getopt.h>
#include <libgen.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <signal.h>
#include <unistd.h>

#include <syslog.h>

#include <sys/epoll.h>
#include <sys/stat.h>
#include <sys/types.h>

#include <thermal.h>
#include "thermal-tools.h"

struct options {
	int loglevel;
	int logopt;
	int interactive;
	int daemonize;
};

struct thermal_data {
	struct thermal_zone *tz;
	struct thermal_handler *th;
};

static int show_trip(struct thermal_trip *tt, __maybe_unused void *arg)
{
	INFO("trip id=%d, type=%d, temp=%d, hyst=%d\n",
	     tt->id, tt->type, tt->temp, tt->hyst);

	return 0;
}

static int show_temp(struct thermal_zone *tz, __maybe_unused void *arg)
{
	thermal_cmd_get_temp(arg, tz);

	INFO("temperature: %d\n", tz->temp);

	return 0;
}

static int show_governor(struct thermal_zone *tz, __maybe_unused void *arg)
{
	thermal_cmd_get_governor(arg, tz);

	INFO("governor: '%s'\n", tz->governor);

	return 0;
}

static int show_tz(struct thermal_zone *tz, __maybe_unused void *arg)
{
	INFO("thermal zone '%s', id=%d\n", tz->name, tz->id);

	for_each_thermal_trip(tz->trip, show_trip, NULL);

	show_temp(tz, arg);

	show_governor(tz, arg);

	return 0;
}

static int tz_create(const char *name, int tz_id, __maybe_unused void *arg)
{
	INFO("Thermal zone '%s'/%d created\n", name, tz_id);

	return 0;
}

static int tz_delete(int tz_id, __maybe_unused void *arg)
{
	INFO("Thermal zone %d deleted\n", tz_id);

	return 0;
}

static int tz_disable(int tz_id, void *arg)
{
	struct thermal_data *td = arg;
	struct thermal_zone *tz = thermal_zone_find_by_id(td->tz, tz_id);

	INFO("Thermal zone %d ('%s') disabled\n", tz_id, tz->name);

	return 0;
}

static int tz_enable(int tz_id, void *arg)
{
	struct thermal_data *td = arg;
	struct thermal_zone *tz = thermal_zone_find_by_id(td->tz, tz_id);

	INFO("Thermal zone %d ('%s') enabled\n", tz_id, tz->name);

	return 0;
}

static int trip_high(int tz_id, int trip_id, int temp, void *arg)
{
	struct thermal_data *td = arg;
	struct thermal_zone *tz = thermal_zone_find_by_id(td->tz, tz_id);

	INFO("Thermal zone %d ('%s'): trip point %d crossed way up with %d °C\n",
	     tz_id, tz->name, trip_id, temp);

	return 0;
}

static int trip_low(int tz_id, int trip_id, int temp, void *arg)
{
	struct thermal_data *td = arg;
	struct thermal_zone *tz = thermal_zone_find_by_id(td->tz, tz_id);

	INFO("Thermal zone %d ('%s'): trip point %d crossed way down with %d °C\n",
	     tz_id, tz->name, trip_id, temp);

	return 0;
}

static int trip_add(int tz_id, int trip_id, int type, int temp, int hyst, __maybe_unused void *arg)
{
	INFO("Trip point added %d: id=%d, type=%d, temp=%d, hyst=%d\n",
	     tz_id, trip_id, type, temp, hyst);

	return 0;
}

static int trip_delete(int tz_id, int trip_id, __maybe_unused void *arg)
{
	INFO("Trip point deleted %d: id=%d\n", tz_id, trip_id);

	return 0;
}

static int trip_change(int tz_id, int trip_id, int type, int temp,
		       int hyst, __maybe_unused void *arg)
{
	struct thermal_data *td = arg;
	struct thermal_zone *tz = thermal_zone_find_by_id(td->tz, tz_id);

	INFO("Trip point changed %d: id=%d, type=%d, temp=%d, hyst=%d\n",
	     tz_id, trip_id, type, temp, hyst);

	tz->trip[trip_id].type = type;
	tz->trip[trip_id].temp = temp;
	tz->trip[trip_id].hyst = hyst;

	return 0;
}

static int cdev_add(const char *name, int cdev_id, int max_state, __maybe_unused void *arg)
{
	INFO("Cooling device '%s'/%d (max state=%d) added\n", name, cdev_id, max_state);

	return 0;
}

static int cdev_delete(int cdev_id, __maybe_unused void *arg)
{
	INFO("Cooling device %d deleted", cdev_id);

	return 0;
}

static int cdev_update(int cdev_id, int cur_state, __maybe_unused void *arg)
{
	INFO("cdev:%d state:%d\n", cdev_id, cur_state);

	return 0;
}

static int gov_change(int tz_id, const char *name, __maybe_unused void *arg)
{
	struct thermal_data *td = arg;
	struct thermal_zone *tz = thermal_zone_find_by_id(td->tz, tz_id);

	INFO("%s: governor changed %s -> %s\n", tz->name, tz->governor, name);

	strcpy(tz->governor, name);

	return 0;
}

static struct thermal_ops ops = {
	.events.tz_create	= tz_create,
	.events.tz_delete	= tz_delete,
	.events.tz_disable	= tz_disable,
	.events.tz_enable	= tz_enable,
	.events.trip_high	= trip_high,
	.events.trip_low	= trip_low,
	.events.trip_add	= trip_add,
	.events.trip_delete	= trip_delete,
	.events.trip_change	= trip_change,
	.events.cdev_add	= cdev_add,
	.events.cdev_delete	= cdev_delete,
	.events.cdev_update	= cdev_update,
	.events.gov_change	= gov_change
};

static int thermal_event(__maybe_unused int fd, __maybe_unused void *arg)
{
	struct thermal_data *td = arg;

	return thermal_events_handle(td->th, td);
}

static void usage(const char *cmd)
{
	printf("%s : A thermal monitoring engine based on notifications\n", cmd);
	printf("Usage: %s [options]\n", cmd);
	printf("\t-h, --help\t\tthis help\n");
	printf("\t-d, --daemonize\n");
	printf("\t-l <level>, --loglevel <level>\tlog level: ");
	printf("DEBUG, INFO, NOTICE, WARN, ERROR\n");
	printf("\t-s, --syslog\t\toutput to syslog\n");
	printf("\n");
	exit(0);
}

static int options_init(int argc, char *argv[], struct options *options)
{
	int opt;

	struct option long_options[] = {
		{ "help",	no_argument, NULL, 'h' },
		{ "daemonize",	no_argument, NULL, 'd' },
		{ "syslog",	no_argument, NULL, 's' },
		{ "loglevel",	required_argument, NULL, 'l' },
		{ 0, 0, 0, 0 }
	};

	while (1) {

		int optindex = 0;

		opt = getopt_long(argc, argv, "l:dhs", long_options, &optindex);
		if (opt == -1)
			break;

		switch (opt) {
		case 'l':
			options->loglevel = log_str2level(optarg);
			break;
		case 'd':
			options->daemonize = 1;
			break;
		case 's':
			options->logopt = TO_SYSLOG;
			break;
		case 'h':
			usage(basename(argv[0]));
			break;
		default: /* '?' */
			return -1;
		}
	}

	return 0;
}

enum {
	THERMAL_ENGINE_SUCCESS = 0,
	THERMAL_ENGINE_OPTION_ERROR,
	THERMAL_ENGINE_DAEMON_ERROR,
	THERMAL_ENGINE_LOG_ERROR,
	THERMAL_ENGINE_THERMAL_ERROR,
	THERMAL_ENGINE_MAINLOOP_ERROR,
};

int main(int argc, char *argv[])
{
	struct thermal_data td;
	struct options options = {
		.loglevel = LOG_INFO,
		.logopt = TO_STDOUT,
	};

	if (options_init(argc, argv, &options)) {
		ERROR("Usage: %s --help\n", argv[0]);
		return THERMAL_ENGINE_OPTION_ERROR;
	}

	if (options.daemonize && daemon(0, 0)) {
		ERROR("Failed to daemonize: %p\n");
		return THERMAL_ENGINE_DAEMON_ERROR;
	}

	if (log_init(options.loglevel, basename(argv[0]), options.logopt)) {
		ERROR("Failed to initialize logging facility\n");
		return THERMAL_ENGINE_LOG_ERROR;
	}

	td.th = thermal_init(&ops);
	if (!td.th) {
		ERROR("Failed to initialize the thermal library\n");
		return THERMAL_ENGINE_THERMAL_ERROR;
	}

	td.tz = thermal_zone_discover(td.th);
	if (!td.tz) {
		ERROR("No thermal zone available\n");
		return THERMAL_ENGINE_THERMAL_ERROR;
	}

	for_each_thermal_zone(td.tz, show_tz, td.th);

	if (mainloop_init()) {
		ERROR("Failed to initialize the mainloop\n");
		return THERMAL_ENGINE_MAINLOOP_ERROR;
	}

	if (mainloop_add(thermal_events_fd(td.th), thermal_event, &td)) {
		ERROR("Failed to setup the mainloop\n");
		return THERMAL_ENGINE_MAINLOOP_ERROR;
	}

	INFO("Waiting for thermal events ...\n");

	if (mainloop(-1)) {
		ERROR("Mainloop failed\n");
		return THERMAL_ENGINE_MAINLOOP_ERROR;
	}

	return THERMAL_ENGINE_SUCCESS;
}