# Copyright (c) 2011 OpenStack Foundation
# All Rights Reserved.
#
#    Licensed under the Apache License, Version 2.0 (the "License"); you may
#    not use this file except in compliance with the License. You may obtain
#    a copy of the License at
#
#         http://www.apache.org/licenses/LICENSE-2.0
#
#    Unless required by applicable law or agreed to in writing, software
#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
#    License for the specific language governing permissions and limitations
#    under the License.

import abc
import re
import string

import netaddr

from trove.common import cfg
from trove.common import exception
from trove.common.i18n import _

CONF = cfg.CONF


class Base(object):
    def serialize(self):
        return self.__dict__

    def deserialize(self, o):
        self.__dict__ = o

    @classmethod
    def _validate_dict(cls, value):
        reqs = cls._dict_requirements()
        return (isinstance(value, dict) and
                all(key in value for key in reqs))

    @classmethod
    @abc.abstractmethod
    def _dict_requirements(cls):
        """Get the dictionary requirements for a user created via
        deserialization.
        :returns:           List of required dictionary keys.
        """


class DatastoreSchema(Base):
    """Represents a database schema."""

    def __init__(self):
        self._name = None
        self._collate = None
        self._character_set = None

    @classmethod
    def deserialize_schema(cls, value):
        if not cls._validate_dict(value):
            raise ValueError(_("Bad dictionary. Keys: %(keys)s. "
                               "Required: %(reqs)s")
                             % ({'keys': value.keys(),
                                 'reqs': cls._dict_requirements()}))
        schema = cls(deserializing=True)
        schema.deserialize(value)
        return schema

    @property
    def name(self):
        return self._name

    @name.setter
    def name(self, value):
        self._validate_schema_name(value)
        self._name = value

    @property
    def collate(self):
        return self._collate

    @property
    def character_set(self):
        return self._character_set

    def _validate_schema_name(self, value):
        """Perform validations on a given schema name.
        :param value:        Validated schema name.
        :type value:         string
        :raises:             ValueError On validation errors.
        """
        if self._max_schema_name_length and (len(value) >
                                             self._max_schema_name_length):
            raise ValueError(_("Schema name '%(name)s' is too long. "
                               "Max length = %(max_length)d.")
                             % {'name': value,
                                'max_length': self._max_schema_name_length})
        elif not self._is_valid_schema_name(value):
            raise ValueError(_("'%s' is not a valid schema name.") % value)

    @abc.abstractproperty
    def _max_schema_name_length(self):
        """Return the maximum valid schema name length if any.
        :returns:            Maximum schema name length or None if unlimited.
        """

    @abc.abstractmethod
    def _is_valid_schema_name(self, value):
        """Validate a given schema name.
        :param value:        Validated schema name.
        :type value:         string
        :returns:            TRUE if valid, FALSE otherwise.
        """

    @classmethod
    @abc.abstractmethod
    def _dict_requirements(cls):
        """Get the dictionary requirements for a user created via
        deserialization.
        :returns:           List of required dictionary keys.
        """


class MongoDBSchema(DatastoreSchema):
    """Represents the MongoDB schema and its associated properties.

    MongoDB database names are limited to 128 characters,
    alphanumeric and - and _ only.
    """

    name_regex = re.compile(r'^[a-zA-Z0-9_\-]+$')

    def __init__(self, name=None, deserializing=False):
        super(MongoDBSchema, self).__init__()
        # need one or the other, not both, not none (!= ~ XOR)
        if not (bool(deserializing) != bool(name)):
            raise ValueError(_("Bad args. name: %(name)s, "
                               "deserializing %(deser)s.")
                             % ({'name': bool(name),
                                 'deser': bool(deserializing)}))
        if not deserializing:
            self.name = name

    @property
    def _max_schema_name_length(self):
        return 64

    def _is_valid_schema_name(self, value):
        # check against the invalid character set from
        # http://docs.mongodb.org/manual/reference/limits
        return not any(c in value for c in '/\. "$')

    @classmethod
    def _dict_requirements(cls):
        return ['_name']


class MySQLDatabase(Base):
    """Represents a Database and its properties."""

    _ignore_dbs = CONF.ignore_dbs

    # Defaults
    __charset__ = "utf8"
    __collation__ = "utf8_general_ci"
    dbname = re.compile("^[A-Za-z0-9_-]+[\s\?\#\@]*[A-Za-z0-9_-]+$")

    # Complete list of acceptable values
    charset = {"big5": ["big5_chinese_ci", "big5_bin"],
               "dec8": ["dec8_swedish_ci", "dec8_bin"],
               "cp850": ["cp850_general_ci", "cp850_bin"],
               "hp8": ["hp8_english_ci", "hp8_bin"],
               "koi8r": ["koi8r_general_ci", "koi8r_bin"],
               "latin1": ["latin1_swedish_ci",
                          "latin1_german1_ci",
                          "latin1_danish_ci",
                          "latin1_german2_ci",
                          "latin1_bin",
                          "latin1_general_ci",
                          "latin1_general_cs",
                          "latin1_spanish_ci"],
               "latin2": ["latin2_general_ci",
                          "latin2_czech_cs",
                          "latin2_hungarian_ci",
                          "latin2_croatian_ci",
                          "latin2_bin"],
               "swe7": ["swe7_swedish_ci", "swe7_bin"],
               "ascii": ["ascii_general_ci", "ascii_bin"],
               "ujis": ["ujis_japanese_ci", "ujis_bin"],
               "sjis": ["sjis_japanese_ci", "sjis_bin"],
               "hebrew": ["hebrew_general_ci", "hebrew_bin"],
               "tis620": ["tis620_thai_ci", "tis620_bin"],
               "euckr": ["euckr_korean_ci", "euckr_bin"],
               "koi8u": ["koi8u_general_ci", "koi8u_bin"],
               "gb2312": ["gb2312_chinese_ci", "gb2312_bin"],
               "greek": ["greek_general_ci", "greek_bin"],
               "cp1250": ["cp1250_general_ci",
                          "cp1250_czech_cs",
                          "cp1250_croatian_ci",
                          "cp1250_bin",
                          "cp1250_polish_ci"],
               "gbk": ["gbk_chinese_ci", "gbk_bin"],
               "latin5": ["latin5_turkish_ci", "latin5_bin"],
               "armscii8": ["armscii8_general_ci", "armscii8_bin"],
               "utf8": ["utf8_general_ci",
                        "utf8_bin",
                        "utf8_unicode_ci",
                        "utf8_icelandic_ci",
                        "utf8_latvian_ci",
                        "utf8_romanian_ci",
                        "utf8_slovenian_ci",
                        "utf8_polish_ci",
                        "utf8_estonian_ci",
                        "utf8_spanish_ci",
                        "utf8_swedish_ci",
                        "utf8_turkish_ci",
                        "utf8_czech_ci",
                        "utf8_danish_ci",
                        "utf8_lithuanian_ci",
                        "utf8_slovak_ci",
                        "utf8_spanish2_ci",
                        "utf8_roman_ci",
                        "utf8_persian_ci",
                        "utf8_esperanto_ci",
                        "utf8_hungarian_ci"],
               "ucs2": ["ucs2_general_ci",
                        "ucs2_bin",
                        "ucs2_unicode_ci",
                        "ucs2_icelandic_ci",
                        "ucs2_latvian_ci",
                        "ucs2_romanian_ci",
                        "ucs2_slovenian_ci",
                        "ucs2_polish_ci",
                        "ucs2_estonian_ci",
                        "ucs2_spanish_ci",
                        "ucs2_swedish_ci",
                        "ucs2_turkish_ci",
                        "ucs2_czech_ci",
                        "ucs2_danish_ci",
                        "ucs2_lithuanian_ci",
                        "ucs2_slovak_ci",
                        "ucs2_spanish2_ci",
                        "ucs2_roman_ci",
                        "ucs2_persian_ci",
                        "ucs2_esperanto_ci",
                        "ucs2_hungarian_ci"],
               "cp866": ["cp866_general_ci", "cp866_bin"],
               "keybcs2": ["keybcs2_general_ci", "keybcs2_bin"],
               "macce": ["macce_general_ci", "macce_bin"],
               "macroman": ["macroman_general_ci", "macroman_bin"],
               "cp852": ["cp852_general_ci", "cp852_bin"],
               "latin7": ["latin7_general_ci",
                          "latin7_estonian_cs",
                          "latin7_general_cs",
                          "latin7_bin"],
               "cp1251": ["cp1251_general_ci",
                          "cp1251_bulgarian_ci",
                          "cp1251_ukrainian_ci",
                          "cp1251_bin",
                          "cp1251_general_cs"],
               "cp1256": ["cp1256_general_ci", "cp1256_bin"],
               "cp1257": ["cp1257_general_ci",
                          "cp1257_lithuanian_ci",
                          "cp1257_bin"],
               "binary": ["binary"],
               "geostd8": ["geostd8_general_ci", "geostd8_bin"],
               "cp932": ["cp932_japanese_ci", "cp932_bin"],
               "eucjpms": ["eucjpms_japanese_ci", "eucjpms_bin"]}

    collation = {"big5_chinese_ci": "big5",
                 "big5_bin": "big5",
                 "dec8_swedish_ci": "dec8",
                 "dec8_bin": "dec8",
                 "cp850_general_ci": "cp850",
                 "cp850_bin": "cp850",
                 "hp8_english_ci": "hp8",
                 "hp8_bin": "hp8",
                 "koi8r_general_ci": "koi8r",
                 "koi8r_bin": "koi8r",
                 "latin1_german1_ci": "latin1",
                 "latin1_swedish_ci": "latin1",
                 "latin1_danish_ci": "latin1",
                 "latin1_german2_ci": "latin1",
                 "latin1_bin": "latin1",
                 "latin1_general_ci": "latin1",
                 "latin1_general_cs": "latin1",
                 "latin1_spanish_ci": "latin1",
                 "latin2_czech_cs": "latin2",
                 "latin2_general_ci": "latin2",
                 "latin2_hungarian_ci": "latin2",
                 "latin2_croatian_ci": "latin2",
                 "latin2_bin": "latin2",
                 "swe7_swedish_ci": "swe7",
                 "swe7_bin": "swe7",
                 "ascii_general_ci": "ascii",
                 "ascii_bin": "ascii",
                 "ujis_japanese_ci": "ujis",
                 "ujis_bin": "ujis",
                 "sjis_japanese_ci": "sjis",
                 "sjis_bin": "sjis",
                 "hebrew_general_ci": "hebrew",
                 "hebrew_bin": "hebrew",
                 "tis620_thai_ci": "tis620",
                 "tis620_bin": "tis620",
                 "euckr_korean_ci": "euckr",
                 "euckr_bin": "euckr",
                 "koi8u_general_ci": "koi8u",
                 "koi8u_bin": "koi8u",
                 "gb2312_chinese_ci": "gb2312",
                 "gb2312_bin": "gb2312",
                 "greek_general_ci": "greek",
                 "greek_bin": "greek",
                 "cp1250_general_ci": "cp1250",
                 "cp1250_czech_cs": "cp1250",
                 "cp1250_croatian_ci": "cp1250",
                 "cp1250_bin": "cp1250",
                 "cp1250_polish_ci": "cp1250",
                 "gbk_chinese_ci": "gbk",
                 "gbk_bin": "gbk",
                 "latin5_turkish_ci": "latin5",
                 "latin5_bin": "latin5",
                 "armscii8_general_ci": "armscii8",
                 "armscii8_bin": "armscii8",
                 "utf8_general_ci": "utf8",
                 "utf8_bin": "utf8",
                 "utf8_unicode_ci": "utf8",
                 "utf8_icelandic_ci": "utf8",
                 "utf8_latvian_ci": "utf8",
                 "utf8_romanian_ci": "utf8",
                 "utf8_slovenian_ci": "utf8",
                 "utf8_polish_ci": "utf8",
                 "utf8_estonian_ci": "utf8",
                 "utf8_spanish_ci": "utf8",
                 "utf8_swedish_ci": "utf8",
                 "utf8_turkish_ci": "utf8",
                 "utf8_czech_ci": "utf8",
                 "utf8_danish_ci": "utf8",
                 "utf8_lithuanian_ci": "utf8",
                 "utf8_slovak_ci": "utf8",
                 "utf8_spanish2_ci": "utf8",
                 "utf8_roman_ci": "utf8",
                 "utf8_persian_ci": "utf8",
                 "utf8_esperanto_ci": "utf8",
                 "utf8_hungarian_ci": "utf8",
                 "ucs2_general_ci": "ucs2",
                 "ucs2_bin": "ucs2",
                 "ucs2_unicode_ci": "ucs2",
                 "ucs2_icelandic_ci": "ucs2",
                 "ucs2_latvian_ci": "ucs2",
                 "ucs2_romanian_ci": "ucs2",
                 "ucs2_slovenian_ci": "ucs2",
                 "ucs2_polish_ci": "ucs2",
                 "ucs2_estonian_ci": "ucs2",
                 "ucs2_spanish_ci": "ucs2",
                 "ucs2_swedish_ci": "ucs2",
                 "ucs2_turkish_ci": "ucs2",
                 "ucs2_czech_ci": "ucs2",
                 "ucs2_danish_ci": "ucs2",
                 "ucs2_lithuanian_ci": "ucs2",
                 "ucs2_slovak_ci": "ucs2",
                 "ucs2_spanish2_ci": "ucs2",
                 "ucs2_roman_ci": "ucs2",
                 "ucs2_persian_ci": "ucs2",
                 "ucs2_esperanto_ci": "ucs2",
                 "ucs2_hungarian_ci": "ucs2",
                 "cp866_general_ci": "cp866",
                 "cp866_bin": "cp866",
                 "keybcs2_general_ci": "keybcs2",
                 "keybcs2_bin": "keybcs2",
                 "macce_general_ci": "macce",
                 "macce_bin": "macce",
                 "macroman_general_ci": "macroman",
                 "macroman_bin": "macroman",
                 "cp852_general_ci": "cp852",
                 "cp852_bin": "cp852",
                 "latin7_estonian_cs": "latin7",
                 "latin7_general_ci": "latin7",
                 "latin7_general_cs": "latin7",
                 "latin7_bin": "latin7",
                 "cp1251_bulgarian_ci": "cp1251",
                 "cp1251_ukrainian_ci": "cp1251",
                 "cp1251_bin": "cp1251",
                 "cp1251_general_ci": "cp1251",
                 "cp1251_general_cs": "cp1251",
                 "cp1256_general_ci": "cp1256",
                 "cp1256_bin": "cp1256",
                 "cp1257_lithuanian_ci": "cp1257",
                 "cp1257_bin": "cp1257",
                 "cp1257_general_ci": "cp1257",
                 "binary": "binary",
                 "geostd8_general_ci": "geostd8",
                 "geostd8_bin": "geostd8",
                 "cp932_japanese_ci": "cp932",
                 "cp932_bin": "cp932",
                 "eucjpms_japanese_ci": "eucjpms",
                 "eucjpms_bin": "eucjpms"}

    def __init__(self):
        self._name = None
        self._collate = None
        self._character_set = None

    @property
    def name(self):
        return self._name

    def _is_valid(self, value):
        return value.lower() not in self._ignore_dbs

    @name.setter
    def name(self, value):
        self._name = value

    @property
    def collate(self):
        """Get the appropriate collate value."""
        if not self._collate and not self._character_set:
            return self.__collation__
        elif not self._collate:
            return self.charset[self._character_set][0]
        else:
            return self._collate

    @collate.setter
    def collate(self, value):
        """Validate the collation and set it."""
        if not value:
            pass
        elif self._character_set:
            if value not in self.charset[self._character_set]:
                msg = (_("%(val)s not a valid collation for charset %(char)s.")
                       % {'val': value, 'char': self._character_set})
                raise ValueError(msg)
            self._collate = value
        else:
            if value not in self.collation:
                raise ValueError(_("'%s' not a valid collation.") % value)
            self._collate = value
            self._character_set = self.collation[value]

    @property
    def character_set(self):
        """Get the appropriate character set value."""
        if not self._character_set:
            return self.__charset__
        else:
            return self._character_set

    @character_set.setter
    def character_set(self, value):
        """Validate the character set and set it."""
        if not value:
            pass
        elif value not in self.charset:
            raise ValueError(_("'%s' not a valid character set.") % value)
        else:
            self._character_set = value


class ValidatedMySQLDatabase(MySQLDatabase):
    @MySQLDatabase.name.setter
    def name(self, value):
        if any([not value,
                not self._is_valid(value),
                not self.dbname.match(value),
                string.find("%r" % value, "\\") != -1]):
            raise ValueError(_("'%s' is not a valid database name.") % value)
        elif len(value) > 64:
            msg = _("Database name '%s' is too long. Max length = 64.")
            raise ValueError(msg % value)
        else:
            self._name = value


class DatastoreUser(Base):
    """Represents a datastore user."""

    _HOSTNAME_WILDCARD = '%'

    def __init__(self):
        self._name = None
        self._password = None
        self._host = None
        self._databases = []

    @classmethod
    def deserialize_user(cls, value):
        if not cls._validate_dict(value):
            raise ValueError(_("Bad dictionary. Keys: %(keys)s. "
                               "Required: %(reqs)s")
                             % ({'keys': value.keys(),
                                 'reqs': cls._dict_requirements()}))
        user = cls(deserializing=True)
        user.deserialize(value)
        return user

    @property
    def name(self):
        return self._name

    @name.setter
    def name(self, value):
        self._validate_user_name(value)
        self._name = value

    @property
    def password(self):
        return self._password

    @password.setter
    def password(self, value):
        if self._is_valid_password(value):
            self._password = value
        else:
            raise ValueError(_("'%s' is not a valid password.") % value)

    @property
    def databases(self):
        return self._databases

    @databases.setter
    def databases(self, value):
        mydb = self._build_database_schema(value)
        self._databases.append(mydb.serialize())

    @property
    def host(self):
        if self._host is None:
            return self._HOSTNAME_WILDCARD
        return self._host

    @host.setter
    def host(self, value):
        if self._is_valid_host_name(value):
            self._host = value
        else:
            raise ValueError(_("'%s' is not a valid hostname.") % value)

    @abc.abstractmethod
    def _build_database_schema(self, name):
        """Build a schema for this user.
        :type name:              string
        :type character_set:     string
        :type collate:           string
        """

    def _validate_user_name(self, value):
        """Perform validations on a given user name.
        :param value:        Validated user name.
        :type value:         string
        :raises:             ValueError On validation errors.
        """
        if self._max_username_length and (len(value) >
                                          self._max_username_length):
            raise ValueError(_("User name '%(name)s' is too long. "
                               "Max length = %(max_length)d.")
                             % {'name': value,
                                'max_length': self._max_username_length})
        elif not self._is_valid_name(value):
            raise ValueError(_("'%s' is not a valid user name.") % value)

    @abc.abstractproperty
    def _max_username_length(self):
        """Return the maximum valid user name length if any.
        :returns:            Maximum user name length or None if unlimited.
        """

    @abc.abstractmethod
    def _is_valid_name(self, value):
        """Validate a given user name.
        :param value:        User name to be validated.
        :type value:         string
        :returns:            TRUE if valid, FALSE otherwise.
        """

    @abc.abstractmethod
    def _is_valid_host_name(self, value):
        """Validate a given host name.
        :param value:        Host name to be validated.
        :type value:         string
        :returns:            TRUE if valid, FALSE otherwise.
        """

    @abc.abstractmethod
    def _is_valid_password(self, value):
        """Validate a given password.
        :param value:        Password to be validated.
        :type value:         string
        :returns:            TRUE if valid, FALSE otherwise.
        """

    @classmethod
    @abc.abstractmethod
    def _dict_requirements(cls):
        """Get the dictionary requirements for a user created via
        deserialization.
        :returns:           List of required dictionary keys.
        """


class MongoDBUser(DatastoreUser):
    """Represents a MongoDB user and its associated properties.
    MongoDB users are identified using their namd and database.
    Trove stores this as <database>.<username>
    """

    def __init__(self, name=None, password=None, deserializing=False):
        super(MongoDBUser, self).__init__()
        self._name = None
        self._username = None
        self._database = None
        self._roles = []
        # need only one of: deserializing, name, or (name and password)
        if ((not (bool(deserializing) != bool(name))) or
                (bool(deserializing) and bool(password))):
            raise ValueError(_("Bad args. name: %(name)s, "
                               "password %(pass)s, "
                               "deserializing %(deser)s.")
                             % ({'name': bool(name),
                                 'pass': bool(password),
                                 'deser': bool(deserializing)}))
        if not deserializing:
            self.name = name
            self.password = password

    @property
    def username(self):
        return self._username

    @username.setter
    def username(self, value):
        self._update_name(username=value)

    @property
    def database(self):
        return MongoDBSchema.deserialize_schema(self._database)

    @database.setter
    def database(self, value):
        self._update_name(database=value)

    @property
    def name(self):
        return self._name

    @name.setter
    def name(self, value):
        self._update_name(name=value)

    def _update_name(self, name=None, username=None, database=None):
        """Keep the name, username, and database values in sync."""
        if name:
            (database, username) = self._parse_name(name)
            if not (database and username):
                missing = 'username' if self.database else 'database'
                raise ValueError(_("MongoDB user's name missing %s.")
                                 % missing)
        else:
            if username:
                if not self.database:
                    raise ValueError(_('MongoDB user missing database.'))
                database = self.database.name
            else:  # database
                if not self.username:
                    raise ValueError(_('MongoDB user missing username.'))
                username = self.username
            name = '%s.%s' % (database, username)
        self._name = name
        self._username = username
        self._database = self._build_database_schema(database).serialize()

    @property
    def roles(self):
        return self._roles

    @roles.setter
    def roles(self, value):
        if isinstance(value, list):
            for role in value:
                self._add_role(role)
        else:
            self._add_role(value)

    def revoke_role(self, role):
        if role in self.roles:
            self._roles.remove(role)

    def _init_roles(self):
        if '_roles' not in self.__dict__:
            self._roles = []
            for db in self._databases:
                self._roles.append({'db': db['_name'], 'role': 'readWrite'})

    @classmethod
    def deserialize_user(cls, value):
        user = super(MongoDBUser, cls).deserialize_user(value)
        user.name = user._name
        user._init_roles()
        return user

    def _build_database_schema(self, name):
        return MongoDBSchema(name)

    @staticmethod
    def _parse_name(value):
        """The name will be <database>.<username>, so split it."""
        parts = value.split('.', 1)
        if len(parts) != 2:
            raise exception.BadRequest(_(
                'MongoDB user name "%s" not in <database>.<username> format.'
            ) % value)
        return parts[0], parts[1]

    @property
    def _max_username_length(self):
        return None

    def _is_valid_name(self, value):
        return True

    def _is_valid_host_name(self, value):
        return True

    def _is_valid_password(self, value):
        return True

    def _add_role(self, value):
        if not self._is_valid_role(value):
            raise ValueError(_('Role %s is invalid.') % value)
        self._roles.append(value)
        if value['role'] == 'readWrite':
            self.databases = value['db']

    def _is_valid_role(self, value):
        if not isinstance(value, dict):
            return False
        if not {'db', 'role'} == set(value):
            return False
        return True

    @classmethod
    def _dict_requirements(cls):
        return ['_name']


class MySQLUser(Base):
    """Represents a MySQL User and its associated properties."""

    not_supported_chars = re.compile("^\s|\s$|'|\"|;|`|,|/|\\\\")
    _ignore_users = CONF.ignore_users

    def __init__(self):
        self._name = None
        self._host = None
        self._password = None
        self._databases = []

    def _is_valid(self, value):
        if (not value or
                self.not_supported_chars.search(value) or
                string.find("%r" % value, "\\") != -1):
            return False
        else:
            return True

    def _is_valid_user_name(self, value):
        if (self._is_valid(value) and
                value.lower() not in self._ignore_users):
            return True
        return False

    def _is_valid_host_name(self, value):
        if value in [None, "%"]:
            # % is MySQL shorthand for "everywhere". Always permitted.
            # Null host defaults to % anyway.
            return True
        if CONF.hostname_require_valid_ip:
            try:
                # '%' works as a MySQL wildcard, but it is not a valid
                # part of an IPAddress
                netaddr.IPAddress(value.replace('%', '1'))
            except (ValueError, netaddr.AddrFormatError):
                return False
            else:
                return True
        else:
            # If it wasn't required, anything else goes.
            return True

    @property
    def name(self):
        return self._name

    @name.setter
    def name(self, value):
        if not self._is_valid_user_name(value):
            raise ValueError(_("'%s' is not a valid user name.") % value)
        elif len(value) > 16:
            raise ValueError(_("User name '%s' is too long. Max length = 16.")
                             % value)
        else:
            self._name = value

    @property
    def password(self):
        return self._password

    @password.setter
    def password(self, value):
        if not self._is_valid(value):
            raise ValueError(_("'%s' is not a valid password.") % value)
        else:
            self._password = value

    @property
    def databases(self):
        return self._databases

    @databases.setter
    def databases(self, value):
        mydb = ValidatedMySQLDatabase()
        mydb.name = value
        self._databases.append(mydb.serialize())

    @property
    def host(self):
        if self._host is None:
            return '%'
        return self._host

    @host.setter
    def host(self, value):
        if not self._is_valid_host_name(value):
            raise ValueError(_("'%s' is not a valid hostname.") % value)
        else:
            self._host = value


class RootUser(MySQLUser):
    """Overrides _ignore_users from the MySQLUser class."""

    _ignore_users = []
