from rest_framework.serializers import ModelSerializer, Serializer, IntegerField, BooleanField
from .permission_serializer import PermissionsSerializer
from erp_system.models import RolesModel, PermissionsModel
from rest_framework import serializers


class RolesSerializer(ModelSerializer):
    """
    普通的序列化
    """
    permissions = PermissionsSerializer(many=True, read_only=True)
    delete_flag = serializers.CharField(read_only=True)

    class Meta:
        model = RolesModel
        fields = '__all__'


class RolesPartialSerializer(ModelSerializer):
    """
    给一个角色批量授权的序列化器。
    """

    class Meta:
        model = RolesModel
        fields = ['id', 'permissions']

    def save(self, **kwargs):
        # 针对某一个角色批量授权，之前存在的不变，之前没有的会增加权限
        if self.instance:
            permission_list = self.validated_data.get('permissions')
            current_list = self.instance.permissions.all()

            if permission_list:
                for p in permission_list:
                    if p not in current_list:
                        # 多对多的关联 如果数据库中已经存在对象，则使用add，否则使用
                        # 变量名=变量名.B类名小写_set.create(字段='值')
                        self.instance.permissions.add(p.id)

                self.instance.save()
            return self.instance


class RoleSetPermissionSerializer(Serializer):
    """
    角色单一授权，或者取消单一授权
    """
    #  角色ID
    role_id = IntegerField(write_only=True, required=True, help_text='选择的角色ID')
    permission_id = IntegerField(write_only=True, required=True, help_text='选择的权限ID')
    # 是否是：取消授权还是授予权限
    is_create = BooleanField(write_only=True, required=True, help_text='是否授予还是删除权限')