/* ************************************************************************** */
/*                                                                            */
/*                                                        :::      ::::::::   */
/*   cmd_cd.c                                           :+:      :+:    :+:   */
/*                                                    +:+ +:+         +:+     */
/*   By: tmaze <tmaze@student.42.fr>                +#+  +:+       +#+        */
/*                                                +#+#+#+#+#+   +#+           */
/*   Created: 2019/01/07 16:44:40 by tmaze             #+#    #+#             */
/*   Updated: 2020/01/26 22:17:48 by tmaze            ###   ########.fr       */
/*                                                                            */
/* ************************************************************************** */

#include "minishell.h"

void	*put_error_cd(char *file, char *msg)
{
	ft_putstr("cd: ");
	ft_putstr(file);
	ft_putstr(": ");
	ft_putendl(msg);
	return (NULL);
}

int		put_error_cd2(char *file, char *msg)
{
	ft_putstr("cd: ");
	ft_putstr(file);
	ft_putstr(": ");
	ft_putendl(msg);
	return (1);
}

char	*check_path_slash_cd(char *exec)
{
	int			i;
	struct stat	info;
	struct stat info2;

	if (exec[0] == '/')
	{
		if ((i = access(exec, F_OK)) != 0)
			return (put_error_cd(exec, "no such file or directory"));
		if ((i = lstat(exec, &info)) != 0)
			return (put_error_cd(exec, "can't determine info"));
		if ((S_ISLNK(info.st_mode)
			&& ((i = stat(exec, &info2)) != 0 || !S_ISDIR(info2.st_mode)))
			&& !S_ISDIR(info.st_mode))
			return (put_error_cd(exec, "not a directory"));
		if ((i = access(exec, X_OK)) != 0)
			return (put_error_cd(exec, "permission denied"));
		return (exec);
	}
	return (NULL);
}

int		cmd_cd_update_env(char *path, t_env **env, char opt)
{
	t_env	*pwd;
	char	*oldpwd;
	char	*c_path;
	char	p_path[4096];

	ft_bzero(p_path, 4096);
	if (!(pwd = ft_envgetelem("PWD", *env)))
		return (put_error_cd2(path, "env var PWD undefined"));
	if (getcwd(p_path, 4096) == NULL || (oldpwd = ft_strdup(pwd->val)) == NULL
		|| ft_realpath(path, &c_path) == NULL)
		return (put_error_cd2(path, "error"));
	if (ft_envupdate("PWD", *env, ((opt == 'P') ? p_path : c_path)) == NULL
		|| ft_envupdate("OLDPWD", *env, oldpwd) == NULL)
	{
		ft_strdel(&oldpwd);
		ft_strdel(&c_path);
		return (put_error_cd2(path, "error"));
	}
	ft_strdel(&oldpwd);
	ft_strdel(&c_path);
	return (0);
}

int		cmd_cd_core(char *path, t_env **env, char opt)
{
	t_env	*pwd;

	if (check_path_slash_cd(path) == NULL)
		return (1);
	if (chdir(path) == -1
		|| (pwd = ft_envgetelem("PWD", *env)) == NULL)
	{
		put_error_cd(path, "error");
		return (1);
	}
	return (cmd_cd_update_env(path, env, opt));
}

char	cd_getparams(char **argv, size_t *i)
{
	char	ret[2];
	size_t	j;

	ret[1] = '\0';
	ret[0] = 'L';
	*i = 0;
	while (argv[++(*i)] && argv[*i][0] == '-' && ft_strlen(argv[*i]) > 1)
	{
		j = 1;
		while (argv[*i][j] && (argv[*i][j] == 'L' || argv[*i][j] == 'P'))
			ret[0] = argv[*i][j++];
		if (argv[*i][j] && argv[*i][j] != 'L' && argv[*i][j] != 'P')
		{
			ret[0] = argv[*i][j];
			put_error_cd(ret, "invalid option");
			put_error_cd("usage", "cd [-L|-P] [dir]");
			ret[0] = '\0';
			break ;
		}
	}
	return (ret[0]);
}

int		cmd_cd_switchboard(char **av, t_env **env, char opt, int i)
{
	t_env	*e;
	char	*p;
	int		ret;

	if ((!av[i] && (e = ft_envgetelem("HOME", *env)) != NULL && e->val
		!= NULL) || (av[i] && av[i][0] == '-'
		&& (e = ft_envgetelem("OLDPWD", *env)) != NULL))
		return (cmd_cd_core(e->val, env, opt));
	else if (av[i] && av[i][0] == '/')
		return (cmd_cd_core(av[i], env, opt));
	else if (av[i] && av[i][0] != '/'
		&& (e = ft_envgetelem("PWD", *env)) != NULL && e->val != NULL)
	{
		if ((p = ft_strnew(ft_strlen(e->val) + ft_strlen(av[i]) + 1)) == NULL)
			put_error_cd(av[i], "memory error");
		if (p == NULL)
			return (1);
		ft_strcpy(p, e->val);
		p[ft_strlen(p)] = '/';
		ft_strcat(p, av[i]);
		ret = cmd_cd_core(p, env, opt);
		ft_strdel(&p);
		return (ret);
	}
	return (1);
}

int		cmd_cd(char **argv, t_env **env)
{
	size_t	i;
	char	opt;

	i = 0;
	if ((opt = cd_getparams(argv, &i)) == '\0')
		return (1);
	return (cmd_cd_switchboard(argv, env, opt, i));
}