# -*- coding: UTF-8 -*-

# Copyright (c) 2010, Pascal Volk

# See COPYING for distribution information.

"""

    VirtualMailManager.cli.config

    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

    Adds some interactive stuff to the Config class.

"""

from ConfigParser import RawConfigParser

from shutil import copy2

from VirtualMailManager import ENCODING

from VirtualMailManager.config import Config, ConfigValueError, LazyConfig

from VirtualMailManager.cli import w_err, w_std

from VirtualMailManager.constants import CONF_ERROR, VMM_TOO_MANY_FAILURES

_ = lambda msg: msg

class CliConfig(Config):

    """Adds the interactive ``configure`` method to the `Config` class

    and overwrites `LazyConfig.set(), in order to update a single option

    in the configuration file with a single command line command.

    """

    def configure(self, sections):

        """Interactive method for configuring all options of the given

        iterable ``sections`` object."""

        input_fmt = _(u'Enter new value for option %(option)s '

                      u'[%(current_value)s]: ')

        failures = 0

        w_std(_(u'Using configuration file: %s\n') % self._cfg_filename)

        for section in sections:

            w_std(_(u"* Configuration section: '%s'") % section)

            for opt, val in self.items(section):

                failures = 0

                while True:

                    newval = raw_input(input_fmt.encode(ENCODING, 'replace') %

                                       {'option': opt, 'current_value': val})

                    if newval and newval != val:

                        try:

                            LazyConfig.set(self, '%s.%s' % (section, opt),

                                           newval)

                            break

                            w_err(0, _(u'Warning: %s') % err)

                            failures += 1

                            if failures > 2:

                                raise ConfigError(_(u'Too many failures - try '

                                                    u'again later.'),

                                                  VMM_TOO_MANY_FAILURES)

                    else:

                        break

            print

        if self._modified:

            self._save_changes()

    def set(self, option, value):

        """Set the value of an option.

        If the new `value` has been set, the configuration file will be

        immediately updated.

        Throws a ``ConfigError`` if `value` couldn't be converted to

        ``LazyConfigOption.cls`` or ``LazyConfigOption.validate`` fails."""

        section, option_ = self._get_section_option(option)

        try:

            val = self._cfg[section][option_].cls(value)

            if self._cfg[section][option_].validate:

                val = self._cfg[section][option_].validate(val)

        except (ValueError, ConfigValueError), err:

            raise ConfigError(str(err), CONF_ERROR)

        # Do not write default values also skip identical values

        if not self._cfg[section][option_].default is None:

            old_val = self.dget(option)

        else:

            old_val = self.pget(option)

        if val == old_val:

            return

        if not RawConfigParser.has_section(self, section):

            self.add_section(section)

        RawConfigParser.set(self, section, option_, val)

        self._save_changes()

    def _save_changes(self):

        """Writes changes to the configuration file."""

        copy2(self._cfg_filename, self._cfg_filename + '.bak')

        self._cfg_file = open(self._cfg_filename, 'w')

        self.write(self._cfg_file)

        self._cfg_file.close()

del _