"""passbook audit models"""
from json import dumps, loads
from logging import getLogger

from django.conf import settings
from django.core.exceptions import ValidationError
from django.db import models
from django.utils.translation import gettext as _
from ipware import get_client_ip
from reversion import register

from passbook.lib.models import UUIDModel

LOGGER = getLogger(__name__)

@register()
class AuditEntry(UUIDModel):
    """An individual audit log entry"""

    ACTION_LOGIN = 'login'
    ACTION_LOGIN_FAILED = 'login_failed'
    ACTION_LOGOUT = 'logout'
    ACTION_AUTHORIZE_APPLICATION = 'authorize_application'
    ACTION_SUSPICIOUS_REQUEST = 'suspicious_request'
    ACTION_SIGN_UP = 'sign_up'
    ACTION_PASSWORD_RESET = 'password_reset'
    ACTION_INVITE_CREATED = 'invite_created'
    ACTION_INVITE_USED = 'invite_used'
    ACTIONS = (
        (ACTION_LOGIN, ACTION_LOGIN),
        (ACTION_LOGIN_FAILED, ACTION_LOGIN_FAILED),
        (ACTION_LOGOUT, ACTION_LOGOUT),
        (ACTION_AUTHORIZE_APPLICATION, ACTION_AUTHORIZE_APPLICATION),
        (ACTION_SUSPICIOUS_REQUEST, ACTION_SUSPICIOUS_REQUEST),
        (ACTION_SIGN_UP, ACTION_SIGN_UP),
        (ACTION_PASSWORD_RESET, ACTION_PASSWORD_RESET),
        (ACTION_INVITE_CREATED, ACTION_INVITE_CREATED),
        (ACTION_INVITE_USED, ACTION_INVITE_USED),
    )

    user = models.ForeignKey(settings.AUTH_USER_MODEL, null=True, on_delete=models.SET_NULL)
    action = models.TextField(choices=ACTIONS)
    date = models.DateTimeField(auto_now_add=True)
    app = models.TextField()
    _context = models.TextField()
    _context_cache = None
    request_ip = models.GenericIPAddressField()

    @property
    def context(self):
        """Load context data and load json"""
        if not self._context_cache:
            self._context_cache = loads(self._context)
        return self._context_cache

    @staticmethod
    def create(action, request, **kwargs):
        """Create AuditEntry from arguments"""
        client_ip, _ = get_client_ip(request)
        entry = AuditEntry.objects.create(
            action=action,
            user=request.user,
            # User 0.0.0.0 as fallback if IP cannot be determined
            request_ip=client_ip or '0.0.0.0',
            _context=dumps(kwargs))
        LOGGER.debug("Logged %s from %s (%s)", action, request.user, client_ip)
        return entry

    def save(self, *args, **kwargs):
        if not self._state.adding:
            raise ValidationError("you may not edit an existing %s" % self._meta.model_name)
        super().save(*args, **kwargs)

    class Meta:

        verbose_name = _('Audit Entry')
        verbose_name_plural = _('Audit Entries')