#include <time.h>
#include <stdlib.h>
#include <stdio.h>
#include "../src/sc_timer_service.h"
#include "../src-gen/Statechart.h"
#include "../src-gen/Statechart_required.h"
#include "./data_types.h"
#include "./pid.h"

#define TARGET_DIST 100

// YAKINDU forces us to use global variables so don't blame me
#define MAX_TIMERS 4
static sc_timer_t timers[MAX_TIMERS];
static sc_timer_service_t timer_service;

// Observers are stateless (they just link to callbacks) so it's safe to use global variables here
static sc_single_subscription_observer_int32_t observer_motorL;
static sc_single_subscription_observer_int32_t observer_motorR;

static int32_t motor_left_speed;
static int32_t motor_right_speed;

// event handler callback functions
void on_motorL(Statechart* sc, int32_t value) {
	fprintf(stderr, "got event motorL: %f\n", value);
	motor_left_speed = value;
}
void on_motorR(Statechart* sc, int32_t value) {
	fprintf(stderr, "got event motorR: %f\n", value);
	motor_right_speed = value;
}

// called once, on startup
void controller_init(Statechart* sc) {
	sc_timer_service_init(&timer_service, timers, MAX_TIMERS,
		(sc_raise_time_event_fp) &statechart_raise_time_event);

	statechart_init(sc);
	statechart_enter(sc);

	// subscribe to output events:

	// motorL observer
	sc_single_subscription_observer_int32_t_init(&observer_motorL, sc, (sc_observer_next_int32_t_fp) on_motorL);
	sc_single_subscription_observer_int32_t_subscribe(&observer_motorL, statechart_get_setMotorL(sc));

	// motorR observer
	sc_single_subscription_observer_int32_t_init(&observer_motorR, sc, (sc_observer_next_int32_t_fp) on_motorR);
	sc_single_subscription_observer_int32_t_subscribe(&observer_motorR, statechart_get_setMotorR(sc));
}

// to be called every 10 ms
void controller_poll(int32_t* _motor_left_speed, int32_t* _motor_right_speed) {
	sc_time elapsed = 10; // ms
	sc_timer_service_proceed(&timer_service, elapsed);
	fprintf(stderr, "made 10ms step\n");

	(*_motor_left_speed) = motor_left_speed;
	(*_motor_right_speed) = motor_right_speed;
}

// finally, we need to implemented these functions (defined in "Statechart_required.h")
int32_t statechart_pid(Statechart* handle, const int32_t sensor, pid_vars_t pid_vars) {
	int32_t error = TARGET_DIST - sensor; // is this correct?
	return pid(pid_vars, error);
}
// here you see the reason we need global variables for the timer service:
// the signature of these functions is mandated by YAKINDU, and there is no 'timer service' parameter
void statechart_set_timer(Statechart *sc, const sc_eventid evid, const int32_t time_ms, const sc_boolean periodic) {
	sc_timer_set(&timer_service, sc, evid, time_ms, periodic);
}
void statechart_unset_timer(Statechart *sc, const sc_eventid evid) {
	sc_timer_unset(&timer_service, evid);
}


void main() {
	// find out how big the Statechart-struct is:
	fprintf(stderr, "%d", sizeof(Statechart));
}