# vi: ts=4 expandtab
#
#    Copyright (C) 2014 Harm Weites
#
#    Author: Harm Weites <harm@weites.com>
#
#    This program is free software: you can redistribute it and/or modify
#    it under the terms of the GNU General Public License version 3, as
#    published by the Free Software Foundation.
#
#    This program is distributed in the hope that it will be useful,
#    but WITHOUT ANY WARRANTY; without even the implied warranty of
#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#    GNU General Public License for more details.
#
#    You should have received a copy of the GNU General Public License
#    along with this program.  If not, see <http://www.gnu.org/licenses/>.

from StringIO import StringIO

import re

from cloudinit import distros
from cloudinit import helpers
from cloudinit import log as logging
from cloudinit import ssh_util
from cloudinit import util

LOG = logging.getLogger(__name__)


class Distro(distros.Distro):
    rc_conf_fn = "/etc/rc.conf"
    login_conf_fn = '/etc/login.conf'
    login_conf_fn_bak = '/etc/login.conf.orig'

    def __init__(self, name, cfg, paths):
        distros.Distro.__init__(self, name, cfg, paths)
        # This will be used to restrict certain
        # calls from repeatly happening (when they
        # should only happen say once per instance...)
        self._runner = helpers.Runners(paths)
        self.osfamily = 'freebsd'

    # Updates a key in /etc/rc.conf.
    def updatercconf(self, key, value):
        LOG.debug("updatercconf: %s => %s", key, value)
        conf = self.loadrcconf()
        config_changed = False
        for item in conf:
            if item == key and conf[item] != value:
                conf[item] = value
                LOG.debug("[rc.conf]: Value %s for key %s needs to be changed",
                          value, key)
                config_changed = True

        if config_changed:
            LOG.debug("Writing new %s file", self.rc_conf_fn)
            buf = StringIO()
            for keyval in conf.items():
                buf.write("%s=%s\n" % keyval)
            util.write_file(self.rc_conf_fn, buf.getvalue())

    # Load the contents of /etc/rc.conf and store all keys in a dict.
    def loadrcconf(self):
        conf = {}
        lines = util.load_file(self.rc_conf_fn).splitlines()
        for line in lines:
            tok = line.split('=')
            conf[tok[0]] = tok[1].rstrip()
        return conf

    def readrcconf(self, key):
        conf = self.loadrcconf()
        try:
            val = conf[key]
        except KeyError:
            val = None
        return val

    def _read_system_hostname(self):
        sys_hostname = self._read_hostname()
        return ('rc.conf', sys_hostname)

    def _read_hostname(self, filename, default=None):
        hostname = None
        try:
            hostname = self.readrcconf('hostname')
        except IOError:
            pass
        if not hostname:
            return default
        return hostname

    def _select_hostname(self, hostname, fqdn):
        if not hostname:
            return fqdn
        return hostname

    def _write_hostname(self, hostname, filename):
        self.updatercconf('hostname', hostname)

    def create_group(self, name, members):
        group_add_cmd = ['pw', '-n', name]
        if util.is_group(name):
            LOG.warn("Skipping creation of existing group '%s'", name)
        else:
            try:
                util.subp(group_add_cmd)
                LOG.info("Created new group %s", name)
            except Exception as e:
                util.logexc(LOG, "Failed to create group %s", name)
                raise e

        if len(members) > 0:
            for member in members:
                if not util.is_user(member):
                    LOG.warn("Unable to add group member '%s' to group '%s'"
                             "; user does not exist.", member, name)
                    continue
                try:
                    util.subp(['pw', 'usermod', '-n', name, '-G', member])
                    LOG.info("Added user '%s' to group '%s'", member, name)
                except Exception:
                    util.logexc(LOG, "Failed to add user '%s' to group '%s'",
                                member, name)

    def add_user(self, name, **kwargs):
        if util.is_user(name):
            LOG.info("User %s already exists, skipping.", name)
            return False

        adduser_cmd = ['pw', 'useradd', '-n', name]
        log_adduser_cmd = ['pw', 'useradd', '-n', name]

        adduser_opts = {
                "homedir": '-d',
                "gecos": '-c',
                "primary_group": '-g',
                "groups": '-G',
                "passwd": '-h',
                "shell": '-s',
                "inactive": '-E',
        }
        adduser_flags = {
                "no_user_group": '--no-user-group',
                "system": '--system',
                "no_log_init": '--no-log-init',
        }

        redact_opts = ['passwd']

        for key, val in kwargs.iteritems():
            if key in adduser_opts and val and isinstance(val, basestring):
                adduser_cmd.extend([adduser_opts[key], val])

                # Redact certain fields from the logs
                if key in redact_opts:
                    log_adduser_cmd.extend([adduser_opts[key], 'REDACTED'])
                else:
                    log_adduser_cmd.extend([adduser_opts[key], val])

            elif key in adduser_flags and val:
                adduser_cmd.append(adduser_flags[key])
                log_adduser_cmd.append(adduser_flags[key])

        if 'no_create_home' in kwargs or 'system' in kwargs:
            adduser_cmd.append('-d/nonexistent')
            log_adduser_cmd.append('-d/nonexistent')
        else:
            adduser_cmd.append('-d/usr/home/%s' % name)
            adduser_cmd.append('-m')
            log_adduser_cmd.append('-d/usr/home/%s' % name)
            log_adduser_cmd.append('-m')

        # Run the command
        LOG.info("Adding user %s", name)
        try:
            util.subp(adduser_cmd, logstring=log_adduser_cmd)
        except Exception as e:
            util.logexc(LOG, "Failed to create user %s", name)
            raise e

    # TODO:
    def set_passwd(self, user, passwd, hashed=False):
        return False

    def lock_passwd(self, name):
        try:
            util.subp(['pw', 'usermod', name, '-h', '-'])
        except Exception as e:
            util.logexc(LOG, "Failed to lock user %s", name)
            raise e

    # TODO:
    def write_sudo_rules(self, name, rules, sudo_file=None):
        LOG.debug("[write_sudo_rules] Name: %s", name)

    def create_user(self, name, **kwargs):
        self.add_user(name, **kwargs)

        # Set password if plain-text password provided and non-empty
        if 'plain_text_passwd' in kwargs and kwargs['plain_text_passwd']:
            self.set_passwd(name, kwargs['plain_text_passwd'])

        # Default locking down the account. 'lock_passwd' defaults to True.
        # lock account unless lock_password is False.
        if kwargs.get('lock_passwd', True):
            self.lock_passwd(name)

        # Configure sudo access
        if 'sudo' in kwargs:
            self.write_sudo_rules(name, kwargs['sudo'])

        # Import SSH keys
        if 'ssh_authorized_keys' in kwargs:
            keys = set(kwargs['ssh_authorized_keys']) or []
            ssh_util.setup_user_keys(keys, name, options=None)

    def _write_network(self, settings):
        return

    def apply_locale(self, locale, out_fn=None):
        # Adjust the locals value to the new value
        newconf = StringIO()
        for line in util.load_file(self.login_conf_fn).splitlines():
            newconf.write(re.sub(r'^default:',
                                 r'default:lang=%s:' % locale, line))
            newconf.write("\n")

        # Make a backup of login.conf.
        util.copy(self.login_conf_fn, self.login_conf_fn_bak)

        # And write the new login.conf.
        util.write_file(self.login_conf_fn, newconf.getvalue())

        try:
            LOG.debug("Running cap_mkdb for %s", locale)
            util.subp(['cap_mkdb', self.login_conf_fn])
        except util.ProcessExecutionError:
            # cap_mkdb failed, so restore the backup.
            util.logexc(LOG, "Failed to apply locale %s", locale)
            try:
                util.copy(self.login_conf_fn_bak, self.login_conf_fn)
            except IOError:
                util.logexc(LOG, "Failed to restore %s backup",
                            self.login_conf_fn)

    def install_packages(self, pkglist):
        return

    def package_command(self, cmd, args=None, pkgs=None):
        return

    def set_timezone(self, tz):
        return

    def update_package_sources(self):
        return