from rest_framework import serializers as ser
from .models import Recipe, Ingredient, IngredientWithAmount

class RecipeSerializer(ser.ModelSerializer):
    class Meta:
        model = Recipe
        fields = ('id', 'name', 'category', 'ingredients')



class IngredientSerializer(ser.ModelSerializer):
    class Meta:
        model = Ingredient
        fields = ('id', 'name')


class IngredientWithAmountSerializer(ser.ModelSerializer):
    ingredient = IngredientSerializer()

    class Meta:
        model = IngredientWithAmount
        fields = ('recipe', 'ingredient', 'amount', 'unit', 'display')
        extra_kwargs = {
            'recipe': { 'write_only': True },
        }

    def create(self, validated_data):
        # TODO: better management of ingredient finding
        ingredient, created = Ingredient.objects.get_or_create(
            **validated_data.pop('ingredient')
        )
        if created:
            ingredient.save()
        validated_data['ingredient'] = ingredient
        return IngredientWithAmount.objects.create(
            **validated_data
        )

    def update(self, instance, validated_data):
        for attr in ('recipe', 'amount', 'unit'):
            setattr(
                instance,
                attr,
                validated_data.get(attr,
                    getattr(instance, attr))
            )
        if 'ingredient' in validated_data:
            ingdt, created = Ingredient.objects.get_or_create(
                **validated_data['ingredient']
            )
            if created:
                ingdt.save()
            instance.ingredient = ingdt
        instance.save()

        return instance