from rest_framework import serializers
from ..models import Region


class RegionSerializer(serializers.ModelSerializer):
    children = serializers.SerializerMethodField()

    class Meta:
        model = Region
        fields = ['id', 'name', 'code', 'level', 'parent_id', 'pinyin', 'children']

    def get_children(self, obj):
        children = obj.children.all()
        if children.exists():
            return RegionSerializer(children, many=True).data
        return None


class RegionSimpleSerializer(serializers.ModelSerializer):
    class Meta:
        model = Region
        fields = ['id', 'name', 'code', 'level', 'parent_id', 'pinyin']