# -*- mode: python; coding: utf-8 -*-
# Copyright (C) 2017-2019 by BDE ENS Paris-Saclay
# SPDX-License-Identifier: GPL-3.0-or-later

import datetime
import uuid

from django.contrib.auth.models import AbstractBaseUser, BaseUserManager
from django.db import models
from django.utils import timezone
from django.utils.translation import gettext_lazy as _

from med.settings import MAX_EMPRUNT, REQ_EXPIRE_HRS


class UserManager(BaseUserManager):
    use_in_migrations = True

    def _create_user(self, username, name, surname, email, password=None, su=False):
        """
        Creates and saves a User with the given username, email and password.
        """
        if not username:
            raise ValueError('The given username must be set')
        email = self.normalize_email(email)
        username = self.model.normalize_username(username)
        user = self.model(
            pseudo=username,
            name=name,
            surname=surname,
            email=email,
        )

        user.set_password(password)
        user.save(using=self._db)
        if su:
            user.make_admin()
        return user

    def create_user(self, pseudo, name, surname, email, password=None):
        """
        Creates and saves a User with the given pseudo, name, surname, email,
        and password.
        """
        return self._create_user(pseudo, name, surname, email, password, False)

    def create_superuser(self, pseudo, name, surname, email, password):
        """
        Creates and saves a superuser with the given pseudo, name, surname,
        email, and password.
        """
        return self._create_user(pseudo, name, surname, email, password, True)


class User(AbstractBaseUser):
    PRETTY_NAME = "Utilisateurs"

    name = models.CharField(max_length=255)
    surname = models.CharField(max_length=255)
    email = models.EmailField()
    telephone = models.CharField(max_length=15, null=True, blank=True)
    adresse = models.CharField(max_length=255, null=True, blank=True)
    maxemprunt = models.IntegerField(default=MAX_EMPRUNT, help_text="Maximum d'emprunts autorisés")
    pseudo = models.CharField(max_length=32, unique=True,
                              help_text="Doit contenir uniquement des lettres, chiffres, ou tirets. ")
    comment = models.CharField(help_text="Commentaire, promo", max_length=255, blank=True)
    is_staff = models.BooleanField(
        _('staff status'),
        default=False,
        help_text=_('Designates whether the user can log into this admin site.'),
    )
    is_active = models.BooleanField(
        _('active'),
        default=True,
        help_text=_(
            'Designates whether this user should be treated as active. '
            'Unselect this instead of deleting accounts.'
        ),
    )
    registered = models.DateTimeField(auto_now_add=True)

    USERNAME_FIELD = 'pseudo'
    REQUIRED_FIELDS = ['name', 'surname', 'email']

    objects = UserManager()

    @property
    def is_admin(self):
        try:
            Right.objects.get(user=self, right__listright='admin')
        except Right.DoesNotExist:
            return False
        return True

    @is_admin.setter
    def is_admin(self, value):
        if value and not self.is_admin:
            self.make_admin()
        elif not value and self.is_admin:
            self.un_admin()

    def has_perms(self, perms, obj=None):
        for perm in perms:
            try:
                Right.objects.get(user=self, right__listright=perm)
                return True
            except Right.DoesNotExist:
                return False

    def get_full_name(self):
        return '%s %s' % (self.name, self.surname)

    def get_short_name(self):
        return self.name

    def has_perm(self, perm, obj=None):
        return True

    def has_right(self, right):
        return Right.objects.filter(user=self).filter(right=ListRight.objects.get(listright=right)).exists()

    def has_module_perms(self, app_label):
        # Simplest version again
        return True

    @property
    def is_adherent(self):
        return self in Adhesion.objects.all().order_by('annee_debut').reverse().first().adherent.all()

    def get_admin_right(self):
        admin, created = ListRight.objects.get_or_create(listright="admin")
        return admin

    def make_admin(self):
        """ Make User admin """
        user_admin_right = Right(user=self, right=self.get_admin_right())
        user_admin_right.save()
        self.is_staff = True
        self.save()

    def un_admin(self):
        try:
            user_right = Right.objects.get(user=self, right=self.get_admin_right())
        except Right.DoesNotExist:
            return
        user_right.delete()

    def __str__(self):
        return self.pseudo


class Request(models.Model):
    PASSWD = 'PW'
    EMAIL = 'EM'
    TYPE_CHOICES = (
        (PASSWD, 'Mot de passe'),
        (EMAIL, 'Email'),
    )
    type = models.CharField(max_length=2, choices=TYPE_CHOICES)
    token = models.CharField(max_length=32)
    user = models.ForeignKey('User', on_delete=models.PROTECT)
    created_at = models.DateTimeField(auto_now_add=True, editable=False)
    expires_at = models.DateTimeField()

    def save(self):
        if not self.expires_at:
            self.expires_at = timezone.now() \
                              + datetime.timedelta(hours=REQ_EXPIRE_HRS)
        if not self.token:
            self.token = str(uuid.uuid4()).replace('-', '')  # remove hyphens
        super(Request, self).save()


class Right(models.Model):
    PRETTY_NAME = "Droits affectés à des users"

    user = models.ForeignKey('User', on_delete=models.PROTECT)
    right = models.ForeignKey('ListRight', on_delete=models.PROTECT)

    class Meta:
        verbose_name = _("right")
        verbose_name_plural = _("rights")
        unique_together = ("user", "right")

    def __str__(self):
        return str(self.user)


class ListRight(models.Model):
    PRETTY_NAME = "Liste des droits existants"

    listright = models.CharField(max_length=255, unique=True)
    details = models.CharField(help_text="Description", max_length=255, blank=True)

    def __str__(self):
        return self.listright


class Clef(models.Model):
    nom = models.CharField(max_length=255, unique=True)
    proprio = models.ForeignKey('User', on_delete=models.PROTECT, blank=True, null=True)
    commentaire = models.CharField(max_length=255, null=True, blank=True)


class Adhesion(models.Model):
    annee_debut = models.IntegerField(unique=True)
    annee_fin = models.IntegerField(unique=True)
    adherent = models.ManyToManyField('User', blank=True)