from django.db import models
from django.utils import timezone
from datetime import timedelta
from django.contrib.auth.models import AbstractBaseUser, BaseUserManager

class UserManager(BaseUserManager):
    def create_user(self, email, password=None, **extra_fields):
        if not email:
            raise ValueError('邮箱地址不能为空')
        email = self.normalize_email(email)
        user = self.model(email=email, **extra_fields)
        if password:
            user.set_password(password)
        user.save(using=self._db)
        return user

    def create_superuser(self, email, password=None, **extra_fields):
        extra_fields.setdefault('is_staff', True)
        extra_fields.setdefault('is_superuser', True)
        
        if extra_fields.get('is_staff') is not True:
            raise ValueError('超级用户必须设置is_staff=True')
        if extra_fields.get('is_superuser') is not True:
            raise ValueError('超级用户必须设置is_superuser=True')
            
        return self.create_user(email, password, **extra_fields)

class User(AbstractBaseUser):
    """用户模型，用于登录和账户管理"""
    email = models.EmailField(max_length=255, unique=True, verbose_name="电子邮箱")
    password = models.CharField(max_length=255, verbose_name="密码")
    company = models.CharField(max_length=255, blank=True, null=True, verbose_name="公司名称")
    name = models.CharField(max_length=255, blank=True, null=True, verbose_name="用户姓名")
    is_first_login = models.BooleanField(default=True, verbose_name="是否首次登录")
    last_login = models.DateTimeField(blank=True, null=True, verbose_name="最近登录时间")
    is_active = models.BooleanField(default=True)
    is_staff = models.BooleanField(default=False)
    is_superuser = models.BooleanField(default=False, verbose_name="超级用户状态")

    # 时间戳
    created_at = models.DateTimeField(auto_now_add=True, verbose_name="创建时间")
    updated_at = models.DateTimeField(auto_now=True, verbose_name="更新时间")

    objects = UserManager()

    USERNAME_FIELD = 'email'
    REQUIRED_FIELDS = []

    class Meta:
        verbose_name = "用户"
        verbose_name_plural = verbose_name
        db_table = "users"

    def __str__(self):
        return self.email

    @property
    def is_authenticated(self):
        return True

    def has_perm(self, perm, obj=None):
        """用户是否有特定权限"""
        return self.is_superuser

    def has_module_perms(self, app_label):
        """用户是否有访问特定app的权限"""
        return self.is_superuser

class UserToken(models.Model):
    user = models.ForeignKey(User, on_delete=models.CASCADE, related_name='tokens')
    token = models.CharField(max_length=40, unique=True)
    created_at = models.DateTimeField(auto_now_add=True)
    expired_at = models.DateTimeField()

    def save(self, *args, **kwargs):
        if not self.expired_at:
            # 设置token有效期为30天
            self.expired_at = timezone.now() + timedelta(days=30)
        super().save(*args, **kwargs)

    def is_expired(self):
        return timezone.now() > self.expired_at

    class Meta:
        db_table = 'user_token'