"""
Serializers creating JSONs for every Model from .models
"""
from rest_framework import serializers
from .models import Sport, Criterion, Question, CriterionRating, 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):
    def to_representation(self, sport_instances):

        serialized_data = []

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

        return serialized_data


class SingleSportSerializer(serializers.BaseSerializer):
    def to_representation(self, sport):

        serialized_data = {}

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

        criteria = []

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

            criterion_data["pk"] = 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.
        """

        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"]

        # 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:
                return None

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

        return sport_dictionary


class IncompleteSportSerializer(serializers.BaseSerializer):
    def to_representation(self, incomplete_sports):

        incomplete_sport_list = []

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

            for crit in sport.criteria_ratings.iterator():

                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):
    def to_representation(self, data):

        criteria_list = []

        for crit, active_sports, sum_of_weights in data:

            criterion_dict = {}

            criterion_dict["id"] = crit.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