//
// Created by Antoine Bartuccio on 05/06/2018.
//

#include <string.h>
#include <math.h>
#include <unistd.h>
#include "Elevator.h"
#include "../SharedData/SharedData.h"

SYNCHRONIZED_GETTER(Elevator, ELEVATOR_STATE, state)
SYNCHRONIZED_SETTER(Elevator, ELEVATOR_STATE, state)
SYNCHRONIZED_GETTER(Elevator, int, floor)
SYNCHRONIZED_SETTER(Elevator, int, floor)

void _free__Elevator(THIS(Elevator)){
	DELETE(this->passengers);
	if (this->name != NULL)
		free(this->name);

	pthread_mutex_unlock(&this->mutex_passengers);
	pthread_mutex_destroy(&this->mutex_passengers);

	pthread_mutex_unlock(&this->mutex_state);
	pthread_mutex_destroy(&this->mutex_state);

	pthread_mutex_unlock(&this->mutex_floor);
	pthread_mutex_destroy(&this->mutex_floor);

	free(this);
}

void add_passenger_Elevator(THIS(Elevator), Passenger * passenger){
	pthread_mutex_lock(&this->mutex_passengers);
	this->passengers->insert_tail(this->passengers, ((void *)passenger), sizeof(Passenger));
	printf("Ascenseur %s : Je recoit le passager %s à l'étage %d\nAscenseur %s : J'ai désormais %d passager(s) à mon bord\n", this->name,
	       passenger->get_name(passenger),
	       this->get_floor(this),
	       this->name, this->passengers->get_size(this->passengers));
	pthread_mutex_unlock(&this->mutex_passengers);
}

/**
 * Remove a passenger from an elevator. Efectively remove him from the elevator's passenger list.
 * @SYNCHRONIZED passengers : this elevator's list of passenger is accessed via mutex
 * @param THIS(Elevator) : this
 * @param passenger : the passenger to remove
 */
void remove_passenger_Elevator(THIS(Elevator), Passenger * passenger){
	pthread_mutex_lock(&this->mutex_passengers);
	if (passenger->type == RESIDENT)
		printf("Ascenseur %s : Le résident %s sort à l'étage %d\n", this->name, passenger->get_name(passenger), this->get_floor(this));
	else if (passenger->type == VISITOR)
		printf("Ascenseur %s : Le passager %s sort à l'étage %d\n", this->name, passenger->get_name(passenger), this->get_floor(this));
	this->passengers->remove_inside(this->passengers, passenger, passenger->compare);
	printf("Ascenseur %s : Il reste encore à mon bord %d passagers\n", this->name, this->passengers->get_size(this->passengers));
	pthread_mutex_unlock(&this->mutex_passengers);
}

int get_number_of_passengers_Elevator(THIS(Elevator)){
	int num;
	pthread_mutex_lock(&this->mutex_passengers);
	num = this->passengers->get_size(this->passengers);
	pthread_mutex_unlock(&this->mutex_passengers);
	return num;
}

/**
 * Search the closest floor where the elevator should stop. In practice ( for now ), it means that this function returns the closest floor amongs it's passengers destinations.
 * @THIS(Elevator) a pointer the current Elevator
 * @return the found floor as an int. If no passengers are in the elevator, returns -1.
 * @todo should consider passenger calling the elevator
 */
int get_next_passenger_stop_Elevator(THIS(Elevator)){
	int i, next_floor, temp_floor;
	float min_diff;
	Element* temp_element;
	Passenger* temp_passenger;
	pthread_mutex_lock(&this->mutex_passengers);
	pthread_mutex_lock(&this->mutex_floor);

	min_diff = INFINITY;
	next_floor = -1;

	for(i=0;i<this->passengers->get_size(this->passengers);i++){
		temp_element = this->passengers->get_element(this->passengers, i);
		temp_passenger = (Passenger*) temp_element->get_data(temp_element);
		temp_floor = temp_passenger->get_destination(temp_passenger);
		if(abs(this->floor - temp_floor) < min_diff && temp_floor != this->floor/*beware*/){
			min_diff = abs(this->floor - temp_floor);
			next_floor = temp_floor;
		}
	}

	pthread_mutex_unlock(&this->mutex_passengers);
	pthread_mutex_unlock(&this->mutex_floor);

	return next_floor;
}

int can_get_inside_Elevator(THIS(Elevator), int floor){
	int permission;
	pthread_mutex_lock(&this->mutex_passengers);
	pthread_mutex_lock(&this->mutex_state);
	pthread_mutex_lock(&this->mutex_floor);

	permission = (this->passengers->get_size(this->passengers) < MAX_ELEVATOR_CAPACITY &&
		      /*this->state == WAITING &&*/ this->floor == floor);

	//if(this->floor != floor)
		//printf("DEBUG : Cause de la préemption : l'ascenseur %s n'est pas là !\n", this->name);
	pthread_mutex_unlock(&this->mutex_floor);
	pthread_mutex_unlock(&this->mutex_state);
	pthread_mutex_unlock(&this->mutex_passengers);

	return permission;
}

void repair_Elevator(THIS(Elevator)){
	this->set_state(this, RUNNING);
}

void *runnable_Elevator(void * void_this){
	/* This is where the thread logic will be implemented */
	Elevator * this = (Elevator*) void_this;
	SharedData * data = GET_INSTANCE(SharedData);
	Building * building = data->main_building;

	int next_call;
	int next_passenger_stop;
	int i;

	AGENT_OPTIONS

	printf("Ascenseur %s : Initialisation...\n", this->name);
	while (data->is_active_passengers_left(data)){
		usleep(250000);
		if(this->target_floor == this->get_floor(this)){

			pthread_mutex_lock(&this->mutex_passengers);//on débarque les passagers
			Element* temp_element = this->passengers->head;
			while(temp_element != NULL){ 
				Passenger* temp_passenger = ((Passenger*) temp_element->data);
				if(temp_passenger->get_destination(temp_passenger) == this->get_floor(this)){
					building->signal_elevator_at_floor(building, this->get_floor(this));
				}
				temp_element = temp_element->next;
			}
			pthread_mutex_unlock(&this->mutex_passengers);

			for(i=0;i<building->waiting_floors[this->get_floor(this)];i++){ //on embarque les passagers
				building->signal_elevator_at_floor(building, this->get_floor(this));
			}

			next_passenger_stop = this->get_next_passenger_stop(this);
			next_call = building->get_next_call(building, this->get_floor(this));

			if(next_passenger_stop != -1){
				this->target_floor = next_passenger_stop;
			}else if(next_call != -1){
				this->target_floor = next_call;
			}

		}
		if(this->get_floor(this) != this->target_floor){
			this->set_floor(this, this->target_floor);
			printf("Ascenseur %s :  Je suis en route vers l'étage %d\n", this->name, this->target_floor);
		}
	}

	return NULL;
}

Elevator *_init_Elevator(char * name){
	Elevator * new_elevator = malloc_or_die(sizeof(Elevator));
	new_elevator->name = strdup(name);
	new_elevator->passengers = NEW(List);
	new_elevator->target_floor = 0;
	pthread_mutex_init(&new_elevator->mutex_passengers, NULL);
	pthread_mutex_init(&new_elevator->mutex_state, NULL);
	pthread_mutex_init(&new_elevator->mutex_floor, NULL);

	LINK_ALL(Elevator, new_elevator,
		 runnable,
		 get_number_of_passengers,
		 get_next_passenger_stop,
		 can_get_inside,
		 remove_passenger,
		 add_passenger,
		 get_state,
		 set_state,
		 get_floor,
		 set_floor,
		 repair
	);

	new_elevator->set_floor(new_elevator, 0);
	new_elevator->set_state(new_elevator, WAITING);

	return new_elevator;
}