from rest_framework import serializers
from .models import Nomenclature, Sticker, StickerMovement
from datetime import date
from django.contrib.auth.models import User


class NomenclatureSerializer(serializers.ModelSerializer):
    class Meta:
        model = Nomenclature
        fields = '__all__'

class StickerSerializer(serializers.ModelSerializer):
    is_expired = serializers.SerializerMethodField()
    is_expiring_soon = serializers.SerializerMethodField()
    nomenclature_name = serializers.CharField(source="nomenclature.name", read_only=True)
    nomenclature_gtin = serializers.CharField(source="nomenclature.gtin", read_only=True)
    class Meta:
        model = Sticker
        fields = '__all__'

    def get_is_expired(self, obj):
        return obj.is_expired()

    def get_is_expiring_soon(self, obj):
        return obj.is_expiring_soon()

    def to_representation(self, instance):
        """Обновляем статус при каждом запросе"""
        instance.save()
        return super().to_representation(instance)

class StickerMovementSerializer(serializers.ModelSerializer):
    class Meta:
        model = StickerMovement
        fields = '__all__'





""" Transfer sticks  """


from rest_framework import serializers
from .models import StickerTransferRequest, StickerTransferItem, Sticker

class StickerTransferItemSerializer(serializers.ModelSerializer):
    class Meta:
        model = StickerTransferItem
        fields = ['id', 'sticker', 'quantity']


class StickerTransferRequestSerializer(serializers.ModelSerializer):
    items = StickerTransferItemSerializer(many=True)
    from_user = serializers.StringRelatedField(read_only=True)
    to_user = serializers.PrimaryKeyRelatedField(queryset=User.objects.all())

    class Meta:
        model = StickerTransferRequest
        fields = ['id', 'from_user', 'to_user', 'status', 'created_at', 'items']

    def create(self, validated_data):
        items_data = validated_data.pop('items')
        transfer = StickerTransferRequest.objects.create(**validated_data)
        for item in items_data:
            StickerTransferItem.objects.create(transfer=transfer, **item)
        return transfer