import datetime
from django.conf import settings
import ldapdb.models
from ldapdb.models.fields import CharField, ImageField, IntegerField, ListField

from neuf_ldap.utils import ldap_create, ldap_validate


class LdapUser(ldapdb.models.Model):
    """
        Represents an LDAP posixAccount, inetOrgPerson, shadowAccount entry.
        Ref: http://www.zytrax.com/books/ldap/apa/types.html
    """

    connection_name = 'ldap'

    # LDAP meta-data
    base_dn = settings.LDAP_USER_DN
    object_classes = ['inetOrgPerson', 'posixAccount', 'shadowAccount']

    # inetOrgPerson
    first_name = CharField(db_column='givenName')
    last_name = CharField(db_column='sn')
    full_name = CharField(db_column='cn')
    email = CharField(db_column='mail')
    phone = CharField(db_column='telephoneNumber', blank=True)
    mobile_phone = CharField(db_column='mobile', blank=True)
    photo = ImageField(db_column='jpegPhoto')

    # posixAccount
    id = IntegerField(db_column='uidNumber', unique=True)  # referenced in reset password form
    group = IntegerField(db_column='gidNumber')
    gecos = CharField(db_column='gecos')
    display_name = CharField(db_column='displayname')
    home_directory = CharField(db_column='homeDirectory')
    login_shell = CharField(db_column='loginShell', default=settings.LDAP_LOGIN_SHELL)
    username = CharField(db_column='uid', primary_key=True)

    # shadowAccount
    password = CharField(db_column='userPassword')
    shadowLastChange = IntegerField(db_column='shadowLastChange', default=settings.LDAP_SHADOW_LAST_CHANGE)
    shadowMin = IntegerField(db_column='shadowMin', default=settings.LDAP_SHADOW_MIN)
    shadowMax = IntegerField(db_column='shadowMax', default=settings.LDAP_SHADOW_MAX)
    shadowWarning = IntegerField(db_column='shadowWarning', default=settings.LDAP_SHADOW_WARNING)
    shadowInactive = IntegerField(db_column='shadowInactive')
    shadowExpire = IntegerField(db_column='shadowExpire', default=settings.LDAP_SHADOW_EXPIRE)
    shadowFlag = IntegerField(db_column='shadowFlag', default=settings.LDAP_SHADOW_FLAG)

    # core
    description = CharField(db_column='description')

    # Hack to use django internals for password reset
    last_login = datetime.datetime(2001, 1, 1)

    @staticmethod
    def _days_since_1970():
        epoch = datetime.datetime.utcfromtimestamp(0)
        today = datetime.datetime.today()
        delta = today - epoch

        return delta.days

    def set_password(self, raw_password, commit=True):
        self.password = ldap_create(raw_password)
        # Update last changed password date
        self.shadowLastChange = LdapUser._days_since_1970()

        if commit:
            self.save()

    def check_password(self, raw_password):
        return ldap_validate(raw_password, self.password)

    class Meta:
        managed = False

    def __str__(self):
        return self.username


class LdapGroup(ldapdb.models.Model):
    """ Represents an LDAP posixGroup entry. """

    connection_name = 'ldap'

    # LDAP meta-data
    base_dn = settings.LDAP_GROUP_DN
    object_classes = ['posixGroup']

    # posixGroup attributes
    gid = IntegerField(db_column='gidNumber', unique=True)
    name = CharField(db_column='cn', max_length=200, primary_key=True)
    members = ListField(db_column='memberUid')

    class Meta:
        managed = False

    def __str__(self):
        return self.name


class LdapAutomountMap(ldapdb.models.Model):
    """
    Represents an LDAP automountMap
    Ref: http://www.openldap.org/faq/data/cache/599.html
    """

    connection_name = 'ldap'

    # LDAP meta-data
    base_dn = settings.LDAP_AUTOMOUNT_DN
    object_classes = ['automountMap']

    ou = CharField(db_column='ou', primary_key=True)  # F.ex auto.home

    class Meta:
        managed = False

    def __str__(self):
        return self.ou


class LdapAutomountHome(ldapdb.models.Model):
    """
    Represents an LDAP automount with hardcoded 'auto.home' in the base_dn (!)
    Ref: http://www.openldap.org/faq/data/cache/599.html
    Ref: http://lists.bolloretelecom.eu/pipermail/django-ldapdb/2012-April/000113.html
    """

    connection_name = 'ldap'

    # LDAP meta-data
    base_dn = 'ou=auto.home,{}'.format(settings.LDAP_AUTOMOUNT_DN)
    object_classes = ['automount']

    username = CharField(db_column='cn', primary_key=True)
    automountInformation = CharField(db_column='automountInformation')

    def set_automount_info(self, username=None):
        krb5_automount_info = "-fstype=nfs4,rw,sec=krb5 {}:{}/{}".format(
            settings.FILESERVER_HOST,
            settings.FILESERVER_HOME_PATH,
            username if username is not None else self.username)

        self.automountInformation = krb5_automount_info

    class Meta:
        managed = False

    def __str__(self):
        return self.username