from rest_framework import serializers

from vbv_lernwelt.course.models import (
    Course,
    CourseCategory,
    CourseCompletion,
    CourseSession,
    CourseSessionUser,
)
from vbv_lernwelt.learnpath.models import Circle


class CourseSerializer(serializers.ModelSerializer):
    class Meta:
        model = Course
        fields = ["id", "title", "category_name"]


class CourseCategorySerializer(serializers.ModelSerializer):
    class Meta:
        model = CourseCategory
        fields = [
            "id",
            "title",
            "general",
        ]


class CourseCompletionSerializer(serializers.ModelSerializer):
    class Meta:
        model = CourseCompletion
        fields = [
            "id",
            "created_at",
            "updated_at",
            "user",
            "page_key",
            "page_type",
            "page_slug",
            "course",
            "completion_status",
            "additional_json_data",
        ]


class CourseSessionSerializer(serializers.ModelSerializer):
    learning_path_url = serializers.SerializerMethodField()
    competence_url = serializers.SerializerMethodField()
    media_library_url = serializers.SerializerMethodField()
    course = serializers.SerializerMethodField()
    experts = serializers.SerializerMethodField()

    def get_course(self, obj):
        return CourseSerializer(obj.course).data

    def get_learning_path_url(self, obj):
        return obj.course.get_learning_path_url()

    def get_media_library_url(self, obj):
        return obj.course.get_media_library_url()

    def get_competence_url(self, obj):
        return obj.course.get_competence_url()

    def get_experts(self, obj):
        expert_relations = CourseSessionUser.objects.filter(
            expert__in=Circle.objects.descendant_of(obj.course.coursepage)
        )
        expert_result = []
        for er in expert_relations:
            for circle in er.expert.all():
                expert_result.append(
                    {
                        "user_id": er.user.id,
                        "circle_id": circle.id,
                        "circle_translation_key": circle.translation_key,
                    }
                )
        return expert_result

    class Meta:
        model = CourseSession
        fields = [
            "id",
            "created_at",
            "updated_at",
            "course",
            "title",
            "start_date",
            "end_date",
            "additional_json_data",
            "learning_path_url",
            "competence_url",
            "media_library_url",
            "experts",
        ]