/* ************************************************************************** */
/*                                                                            */
/*                                                        :::      ::::::::   */
/*   philo.c                                            :+:      :+:    :+:   */
/*                                                    +:+ +:+         +:+     */
/*   By: narnaud <narnaud@student.42.fr>            +#+  +:+       +#+        */
/*                                                +#+#+#+#+#+   +#+           */
/*   Created: 2022/05/16 14:03:42 by narnaud           #+#    #+#             */
/*   Updated: 2022/05/20 10:34:10 by narnaud          ###   ########.fr       */
/*                                                                            */
/* ************************************************************************** */

#include "philo.h"

void	*check_halt(void *p)
{	
	int		time;
	t_philo	*philo;

	philo = p;
	while (1)
	{
		usleep(1000);
		time = gettime();
		if (time - philo->last_meal_time > philo->table->param[DIE_TIME])
		{
			printf("%i %d died\n", time, philo->id);
			exit(EXIT_SUCCESS);
		}
		if (philo->meals_done == philo->table->param[MEALS_AMOUNT])
			exit(EXIT_SUCCESS);
	}
}

void	philo_life(t_philo *philo)
{
	t_table		*table;

	table = philo->table;
	while (1)
	{
		sem_wait(table->sptr);
		printf("%i %d has taken a fork\n", gettime(), philo->id);
		sem_wait(table->sptr);
		printf("%i %d has taken a fork\n", gettime(), philo->id);
		philo->last_meal_time = gettime();
		printf("%i %d is eating\n", gettime(), philo->id);
		usleep(table->param[EAT_DURATION] * 1000);
		philo->meals_done++;
		sem_post(table->sptr);
		sem_post(table->sptr);
		printf("%i %d is sleeping\n", gettime(), philo->id);
		usleep(table->param[SLEEP_DURATION] * 1000);
		printf("%i %d is thinking\n", gettime(), philo->id);
	}
}

void	init_philos(t_table *table)
{
	int			i;
	pthread_t	checks;
	int			amount;

	amount = table->param[PHILO_AMOUNT];
	table->pid = malloc(sizeof(pid_t) * amount);
	i = 0;
	while (i < amount)
	{
		table->pid[i] = fork();
		table->philos[i].table = table;
		table->philos[i].id = i;
		table->philos[i].meals_done = 0;
		if (!table->pid[i])
		{
			pthread_create(&checks, NULL, check_halt, table->philos + i);
			philo_life(table->philos + i);
		}
		usleep(500);
		i++;
	}
}

int	main(int argc, char **argv)
{
	static t_table	*table;
	static int		i = 0;
	static int		status;

	sem_unlink("/chopsticks");
	sem_unlink("/death");
	if (argc < 5 || argc > 6)
		return (1);
	table = parsing(argv + 1);
	table->sptr = sem_open("/chopsticks", O_CREAT, 0664,
			table->param[PHILO_AMOUNT]);
	table->death = sem_open("/death", O_CREAT, 0664, 1);
	init_philos(table);
	waitpid(-1, &status, 0);
	while (i < table->param[PHILO_AMOUNT])
	{
		kill(table->pid[i], SIGINT);
		i++;
	}
	sem_unlink("/chopsticks");
	sem_unlink("/deaths");
	return (0);
}