from django.contrib.auth.models import PermissionsMixin, AbstractUser
from django.db import models


# Create your models here.
class Permission(models.Model):
    CODENAMES = [
        ('view', '查看'),
        ('add', '新增'),
        ('edit', '编辑'),
        ('delete', '删除'),
    ]
    resource = models.CharField("资源标识", max_length=50)  # 如 'article', 'menu', 'carousel'
    action = models.CharField("操作", max_length=10, choices=CODENAMES)
    desc = models.CharField("描述", max_length=100)

    class Meta:
        unique_together = ('resource', 'action')

    def __str__(self):
        return f"{self.resource}:{self.action}"


class Role(models.Model):
    name = models.CharField("角色名称", max_length=50, unique=True)
    permissions = models.ManyToManyField('Permission', blank=True)

    def __str__(self):
        return self.name


class Department(models.Model):
    name = models.CharField("部门名称", max_length=100, unique=True)
    parent = models.ForeignKey('self', on_delete=models.CASCADE, null=True, blank=True, verbose_name="上级部门")
    order = models.IntegerField("排序", default=0)

    class Meta:
        verbose_name = "部门"
        verbose_name_plural = "部门管理"

    def __str__(self):
        return self.name


class User(AbstractUser, PermissionsMixin):
    username = models.CharField("英文名/账号", max_length=30, unique=True)
    cname = models.CharField("中文名", max_length=30, blank=True)
    dept = models.ForeignKey('Department', on_delete=models.SET_NULL, null=True, blank=True, verbose_name="所属部门")
    is_active = models.BooleanField(default=True)

    USERNAME_FIELD = 'username'
    REQUIRED_FIELDS = []

    def __str__(self):
        return f"{self.cname} ({self.username})"


# 给 User 关联 Role（多对多）
User.add_to_class('roles', models.ManyToManyField(Role, blank=True))