serializers.py

"""
Serializers creating JSONs for every Model from .models
"""


import base64
from rest_framework import serializers

from .models import Sport, Criterion, Question, validate_rating


class SportListSerializer(serializers.ModelSerializer):
    """
    Serializes all sports.
    """

    class Meta:
        model = Sport
        fields = ("id", "name", "url", "criteria_ratings")


class QuestionListSerializer(serializers.ModelSerializer):
    """
    Serializes all Questions.
    """

    class Meta:
        model = Question
        fields = ("id", "text", "criterion")


class CriterionListSerializer(serializers.ModelSerializer):
    """
    Serializes Criterions
    """

    class Meta:
        model = Criterion
        fields = ("id", "name")


class SmallSportListSerializer(serializers.BaseSerializer):
    """
    Serializes Lists of Sport Objects in a "Simple" Manner, with Criterions being represented in a Bool.
    """

    def to_representation(self, sport_filled_tuples):
        """
        Takes a List of (Sport, bool) tuples to Serialize.
        The Bool Represents whether the Sport is Filled or not.
        """

        serialized_data = []

        for sport, boolean in sport_filled_tuples:
            serialized_data.append(
                {
                    "id": sport.pk,
                    "name": sport.name,
                    "url": sport.url,
                    "is_filled": boolean,
                }
            )

        return serialized_data


class SingleSportSerializer(serializers.BaseSerializer):
    """
    Serializes and Deserializes a Single Sport Object
    """

    def to_representation(self, sport):
        """
        Takes a Single Sport Object and Serializes it and all its Criteria
        """

        serialized_data = {}

        serialized_data["id"] = sport.pk
        serialized_data["name"] = sport.name
        serialized_data["url"] = sport.url

        criteria = []

        for criterion in sport.criteria_ratings.iterator():
            criterion_data = {}

            criterion_data["id"] = criterion.pk
            criterion_data["name"] = criterion.name

            criterion_data["value"] = sport.get_rating(criterion)

            criteria.append(criterion_data)

        serialized_data["criteria"] = criteria

        return serialized_data

    def to_internal_value(self, request):
        """
        The Data in the Request is taken and written to another Dictionary.
        During this process, the Data is Validated on whether the Rating Value and Criterion ID are valid.
        If the Request is PATCHing or PUTting an existing Sport, not every field must be existant.
        So, the existance is explicitly checked.
        TODO: Different Functions based on PUT or PATCH?
        """

        sport_dictionary = {}

        # If The Sport is Being Patched, Name or URL may not be changed.
        # That means that those Fields might not be sent in the Request,
        # leading to needing to check whether they exist.
        if "name" in request.data.keys():
            sport_dictionary["name"] = request.data["name"]

        if "url" in request.data.keys():
            sport_dictionary["url"] = request.data["url"]

        # If the Sport is only now created with a POST-Request, no Criteria can be filled out for it
        # This is because the Admin Frontend doesn't have a list of Criteria ready
        if "criteria" in request.data.keys():

            # A Number of Criteria may be sent with the Sport
            sport_dictionary["criteria"] = []

            # For every Sent Criterion, the ID of the Criterion and the Rating Value is being tested for Validity
            for criterion in request.data["criteria"]:

                value = criterion["value"]
                try:
                    validate_rating(value)
                    crit = Criterion.objects.get(pk=criterion["id"])
                except:  # pylint: disable=bare-except
                    return None

                sport_dictionary["criteria"].append((crit, value))

        return sport_dictionary


class IncompleteSportSerializer(serializers.BaseSerializer):
    """
    Serializes every Sport Object with Incomplete Criteria Ratings.
    Includes the Name and ID of both the Sport and the Criteria.
    """

    def to_representation(self, incomplete_sports):
        """
        Serializes Every given Sport Object and goes through every Criterium to serialize those that are unrated.
        """

        incomplete_sport_list = []

        for sport in incomplete_sports:
            incomplete_sport = {
                "id": sport.pk,
                "name": sport.name,
                "criteria": [],
            }

            for crit in sport.criteria_ratings.iterator():
                # Asking this way to save an indentation and for readability. Would also work when asking for = -1 and handling the append then.
                if sport.get_rating(crit) != -1:
                    continue

                incomplete_sport["criteria"].append(
                    {
                        "id": crit.pk,
                        "name": crit.name,
                    }
                )

            incomplete_sport_list.append(incomplete_sport)

        return incomplete_sport_list


class CriteriaSerializer(serializers.BaseSerializer):
    """
    Serializes Every Criterium and Metadata
    """

    def to_representation(self, data):
        """
        Takes Tuples of (Criterium, Int, Int),
        where the Integers are the Number of Sports in which the Rating is >1
        and the cumulated sum of Ratings >1, respectively
        """

        criteria_list = []

        for crit, active_sports, sum_of_weights in data:

            criterion_dict = {}

            criterion_dict["id"] = crit.pk
            criterion_dict["question_id"] = crit.question.pk
            criterion_dict["name"] = crit.name
            criterion_dict["number_of_sports_active"] = active_sports
            criterion_dict["sum_of_weights"] = sum_of_weights

            criteria_list.append(criterion_dict)

        return criteria_list


class SmallQuestionListSerializer(serializers.BaseSerializer):
    """
    Serializer for a List of Questions
    """

    def to_representation(self, questions):
        """
        Takes a List of Question Objects and JSONifies them, including id, Text in both languages, and Criterion name
        """

        question_list = []

        for question in questions:
            question_list.append(
                {
                    "id": question.pk,
                    "text_de": question.text_de,
                    "text_en": question.text_en,
                    "criterion": question.criterion.name,
                }
            )

        return question_list


class SingleQuestionSerializer(serializers.BaseSerializer):
    """
    Serializer for Single Questions
    """

    def to_representation(self, question):
        """
        Take a Question and JSONify it and its Criterion
        """

        number_of_sports_active, sum_of_weights = question.criterion.get_active_sum()

        question_dict = {
            "id": question.pk,
            "text_de": question.text_de,
            "text_en": question.text_en,
            "criterion": question.criterion.name,
            "number_of_sports_active": number_of_sports_active,
            "sum_of_weights": sum_of_weights,
        }

        return question_dict

    def to_internal_value(self, data):
        """
        Take a Single Question JSON and Validate its Contents
        """

        validated_data = {}

        # Test if Values exist
        if "text_de" in data.keys():
            validated_data["text_de"] = data["text_de"]

        if "text_en" in data.keys():
            validated_data["text_en"] = data["text_en"]

        if "criterion" in data.keys():
            validated_data["criterion"] = data["criterion"]

        return validated_data


class QuestionOrderSerializer(serializers.BaseSerializer):
    """
    Serializer for Question Order Lists
    """

    def to_representation(self, question_order_list):
        """
        Take an ordered Set of QuestionOrderEntry Objects and represent them in JSON
        """

        json_list = []

        for order_entry in question_order_list:
            json_list.append(
                {
                    "id": order_entry.order_id,
                    "type": order_entry.type_of_slot,
                    "question_id": order_entry.question_id,
                }
            )

        return json_list


class SnackTivityListSerializer(serializers.BaseSerializer):
    """
    Serializer to Serialize Snacks and Activities in their Lists
    """

    def to_representation(self, obj_list):
        """
        Takes a Queryset and JSONifies it
        """

        json_list = []

        for obj in obj_list:

            # bug https://code.djangoproject.com/ticket/25528
            has_image = obj.image not in [None, ""]

            json_list.append(
                {
                    "id": obj.pk,
                    "text_de": obj.text_de,
                    "text_en": obj.text_en,
                    "has_image": has_image,
                }
            )

        return json_list


class SingleSnackTivitySerializer(serializers.BaseSerializer):
    def to_internal_value(self, data):

        validated_data = {}

        if "text_de" in data.keys():
            validated_data["text_de"] = data["text_de"]

        if "text_en" in data.keys():
            validated_data["text_en"] = data["text_en"]

        if "image" in data.keys():
            validated_data["image"] = data["image"]
            validated_data["image_type"] = data["image_type"]

        return validated_data

    def to_representation(self, object):

        # bug https://code.djangoproject.com/ticket/25528
        has_image = object.image not in [None, ""]

        if has_image:
            image_base64 = base64.b64encode(object.image.file.read())
            # TODO: Maybe rethink this? Dunno if unsafe.
            image_type = "image/" + object.image.file.name.split(".")[-1]

        else:
            image_base64 = ""
            image_type = ""

        data = {
            "id": object.pk,
            "text_de": object.text_de,
            "text_en": object.text_en or "",
            "has_image": has_image,
            "image_type": image_type,
            "image": image_base64,
        }

        return data