/* ************************************************************************** */
/*                                                                            */
/*                                                        :::      ::::::::   */
/*   export.c                                           :+:      :+:    :+:   */
/*                                                    +:+ +:+         +:+     */
/*   By: lperrey <lperrey@student.42.fr>            +#+  +:+       +#+        */
/*                                                +#+#+#+#+#+   +#+           */
/*   Created: 2021/12/03 13:36:54 by lperrey           #+#    #+#             */
/*   Updated: 2021/12/04 16:07:21 by lperrey          ###   ########.fr       */
/*                                                                            */
/* ************************************************************************** */

#include "minishell.h"

char		*ft_getenv(char *env_var);
size_t		ft_getenv_position(char *env_var);

static int	change_env_value(char *arg);

// in complete shell, must mark all arguments for export
// (Not implemented in minishell)
int	builtin_export(int argc, char *argv[], t_all *c)
{
	int	i;

	(void)argc;
	i = 1;
	while (argv[i])
	{
		if (ft_strchr(argv[i], '='))
		{
			if (!change_env_value(argv[i]))
				return (EXIT_FAILURE);
			if (ft_strncmp(argv[i], "PATH=", 5) == 0)
				c->path = retrieve_path();
		}
		i++;
	}
	return (EXIT_SUCCESS);
}

static int	change_env_value(char *arg)
{
	char	**var_split;
	int		env_position;

	var_split = ft_split(arg, '=');
	if (!var_split)
		return (ft_reti_perror(-1, "builtin_export, ft_split()"));
	env_position = ft_getenv_position(var_split[0]);
	ft_free_2d_arr(var_split);
	if (environ[env_position] == NULL)
	{
		environ = ft_resize_2d_arr(environ, 1);
		if (!environ)
			return (ft_reti_perror(-1, "builtin_export, ft_resize_2d_arr()"));
	}
	environ[env_position] = ft_strdup(arg);
	if (!environ[env_position])
		return (ft_reti_perror(-1, "builtin_export, ft_strdup()"));
	return (0);
}

/*
** Search for an environement variable,
** and return a pointer to the first character after "env_var=" .
** Return NULL if env_var not found.
*/
char	*ft_getenv(char *env_var)
{
	int		i;
	char	*tmp;
	size_t	env_var_len;

	env_var_len = ft_strlen(env_var);
	i = 0;
	tmp = NULL;
	while (!tmp && environ[i])
	{
		if (environ[i][env_var_len] == '=')
		{
			if (ft_strncmp(environ[i], env_var, env_var_len) == 0)
				tmp = &environ[i][env_var_len + 1];
			else
				i++;
		}
		else
			i++;
	}
	return (tmp);
}

/*
** Like ft_getenv(), but return position of env_var instead of value.
** If env_var not found, return last position of **environ (== NULL)
*/
size_t	ft_getenv_position(char *env_var)
{
	int		i;
	int		found;
	size_t	env_var_len;

	env_var_len = ft_strlen(env_var);
	i = 0;
	found = 0;
	while (!found && environ[i])
	{
		if (environ[i][env_var_len] == '=')
		{
			if (ft_strncmp(environ[i], env_var, env_var_len) == 0)
				found = 1;
			else
				i++;
		}
		else
			i++;
	}
	return (i);
}