from rest_framework import serializers

from apps.school.models import (
    SchoolSchedule, SchoolScheduleImage,
    ImageObject, LiveLesson,
)

from .content import (
    ContentSerializer, ContentCreateSerializer, ImageObjectSerializer
)
from .mixins import DispatchContentMixin


class GalleryImageCreateSerializer(serializers.ModelSerializer):

    class Meta:
        model = SchoolScheduleImage
        fields = (
            'id',
            'img',
            'created_at',
            'update_at',
        )

        read_only_fields = (
            'id',
            'created_at',
            'update_at',
        )


class GalleryImageSerializer(GalleryImageCreateSerializer):
    img = ImageObjectSerializer()


class SchoolScheduleSerializer(serializers.ModelSerializer):
    start_at = serializers.TimeField(format='%H:%M')
    schoolschedule_images = serializers.ListSerializer(
        child=GalleryImageCreateSerializer(),
        required=False,
    )

    class Meta:
        model = SchoolSchedule
        fields = (
            'id',
            'weekday',
            'title',
            'short_description',
            'description',
            'materials',
            'age',
            'month_price',
            'day_discount',
            'start_at',
            'schoolschedule_images',
            'cover',
            'trial_lesson',
            'is_camp',
        )

        read_only_fields = (
            'id',
        )

    def create(self, validated_data):
        gallery = validated_data.pop('schoolschedule_images', [])
        schoolschedule = super().create(validated_data)
        self.dispatch_gallery(schoolschedule, gallery)
        return schoolschedule

    def update(self, instance, validated_data):
        gallery = validated_data.pop('schoolschedule_images', [])
        schoolschedule = super().update(instance, validated_data)
        self.dispatch_gallery(schoolschedule, gallery)
        return schoolschedule

    def dispatch_gallery(self, schoolschedule, gallery):
        images = list(SchoolScheduleImage.objects.filter(schoolschedule=schoolschedule).values_list('img', flat=True))
        new_images = []
        for image in gallery:
            if image.get('img'):
                if image['img'].id not in images:
                    SchoolScheduleImage.objects.create(
                        schoolschedule=schoolschedule,
                        img=image['img'],
                    )
                new_images.append(image['img'].id)
        SchoolScheduleImage.objects.filter(schoolschedule=schoolschedule, img__isnull=True).delete()
        SchoolScheduleImage.objects.filter(schoolschedule=schoolschedule, img__in=set(images) - set(new_images)).delete()

    def to_representation(self, instance):
        return SchoolScheduleSerializerImg(instance, context=self.context).to_representation(instance)


class SchoolScheduleSerializerImg(serializers.ModelSerializer):
    start_at = serializers.TimeField(format='%H:%M')
    schoolschedule_images = serializers.ListSerializer(
        child=GalleryImageSerializer(),
        required=False,
    )
    cover = ImageObjectSerializer()

    class Meta:
        model = SchoolSchedule
        fields = (
            'id',
            'weekday',
            'title',
            'short_description',
            'description',
            'materials',
            'age',
            'month_price',
            'day_discount',
            'start_at',
            'schoolschedule_images',
            'cover',
            'trial_lesson',
            'is_camp',
        )

        read_only_fields = (
            'id',
        )


class LiveLessonCreateSerializer(DispatchContentMixin, serializers.ModelSerializer):
    content = serializers.ListSerializer(
        child=ContentCreateSerializer(),
        required=False,
    )
    live = serializers.SerializerMethodField()

    class Meta:
        model = LiveLesson
        fields = (
            'id',
            'title',
            'short_description',
            'stream',
            'date',
            'cover',
            'content',
            'live',
            'materials',
            'created_at',
            'update_at',
            'deactivated_at',
        )

        read_only_fields = (
            'id',
            'created_at',
            'update_at',
            'deactivated_at',
        )

    def get_live(self, object):
        return True

    def create(self, validated_data):
        content = validated_data.pop('content', [])
        lesson = super().create(validated_data)
        self.dispatch_content(lesson, content)
        return lesson

    def update(self, instance, validated_data):
        content = validated_data.pop('content', [])
        lesson = super().update(instance, validated_data)
        self.dispatch_content(lesson, content)
        return lesson

    def to_representation(self, instance):
        return LiveLessonSerializer(instance, context=self.context).to_representation(instance)


class LiveLessonSerializer(serializers.ModelSerializer):
    content = ContentSerializer(many=True)
    live = serializers.SerializerMethodField()
    cover = ImageObjectSerializer()

    class Meta:
        model = LiveLesson
        fields = (
            'id',
            'title',
            'short_description',
            'stream',
            'date',
            'cover',
            'content',
            'live',
            'materials',
            'created_at',
            'update_at',
            'deactivated_at',
        )

        read_only_fields = (
            'id',
            'created_at',
            'update_at',
            'deactivated_at',
        )

    def get_live(self, object):
        return True