from django.contrib.auth import get_user_model
from django.contrib.auth.models import User

from rest_framework import serializers
from django.utils import timezone
from datetime import timedelta

from courses.models import CourseStudent, Classroom
from discussion.models import Comment, Topic, TopicLike, CommentLike

User = get_user_model()


class UserInDetailSerializer(serializers.ModelSerializer):

    class Meta:
        model = User
        fields = sorted((
            'name',
            'cpf',
            'email',
            'institution',
            'city',
            'occupation',
            'groups',
            'courses',
            'date_joined',
            'last_login',
            'topics_created',
            'number_of_likes',
            'comments_created',
        ))

    comments_created = serializers.SerializerMethodField()
    topics_created = serializers.SerializerMethodField()
    number_of_likes = serializers.SerializerMethodField()
    courses = serializers.SerializerMethodField()
    groups = serializers.SerializerMethodField()

    def get_comments_created(self, obj):
        return obj.comment_author.count()

    def get_courses(self, obj):
        needed_stuff = [
            {'percent_progress': x.percent_progress(),
             'course_finished':  x.can_emmit_receipt(),
             'course_name': x.course.name,
             # FIXME
             #  'has_certificate': x.certificate.document_type == 'certificate',
             'has_certificate': False,
             'class_name': x.get_current_class().name
            } for x in obj.coursestudent_set.all()]
        return needed_stuff

    def get_topics_created(self, obj):
        return obj.topic_author.count()

    def get_number_of_likes(self, obj):
        return obj.topiclike_set.count() + obj.commentlike_set.count()

    def get_groups(self, obj):
        return ', '.join([group.name for group in obj.groups.all()])


class UsersByClassSerializer(serializers.Serializer):
    class Meta:
        model = CourseStudent
        fields = sorted((
            'name',
            'cpf',
            'email',
            'last_login',
            # 'percent_progress_by_lesson',
            'percent_progress',
            'course_finished',
            'class_name',
            'city',
            'occupation',
            # 'institution',
            # 'has_certificate',
            'groups',
        ))

    cpf = serializers.SerializerMethodField()
    email = serializers.SerializerMethodField()
    last_login = serializers.SerializerMethodField()
    # has_certificate = serializers.SerializerMethodField()
    percent_progress_by_lesson = serializers.SerializerMethodField()
    percent_progress = serializers.SerializerMethodField()
    course_finished = serializers.SerializerMethodField()
    class_name = serializers.SerializerMethodField()
    city = serializers.SerializerMethodField()
    occupation = serializers.SerializerMethodField()
    # institution = serializers.SerializerMethodField()
    groups = serializers.SerializerMethodField()

    def get_city(self, obj):
        return obj.user.city

    def get_occupation(self, obj):
        return obj.user.occupation

    def get_institution(self, obj):
        return obj.user.institution

    def get_cpf(self, obj):
        return obj.user.cpf

    def get_email(self, obj):
        return obj.user.email

    def get_last_login(self, obj):
        return obj.user.last_login

    # def get_has_certificate(self, obj):
    #     return obj.certificate.document_type == 'certificate'

    def get_percent_progress_by_lesson(self, obj):
        return obj.percent_progress_by_lesson()

    def get_percent_progress(self, obj):
        return obj.percent_progress()

    def get_course_finished(self, obj):
        return obj.can_emmit_receipt()

    def get_class_name(self, obj):
        return obj.get_current_class().name

    def get_groups(self, obj):
        return ', '.join([group.name for group in obj.user.groups.all()])


class UserStatsSerializer(serializers.ModelSerializer):
    last_access = serializers.SerializerMethodField()
    accesses_count = serializers.SerializerMethodField()
    topics = serializers.SerializerMethodField()
    reactions = serializers.SerializerMethodField()
    comments = serializers.SerializerMethodField()

    class Meta:
        model = User
        fields = ('name', 'username', 'email', 'id', 'image', 'last_access',
                  'accesses_count', 'topics', 'reactions', 'comments')

    def get_last_access(self, obj):
        if obj.last_login:
            timestamp_str = obj.last_login.strftime('%d-%m-%Y %H:%M:%S')
            date, hour = timestamp_str.split()
            return date + ' às ' + hour
        return ''

    def get_accesses_count(self, obj):
        time_delta = timezone.now() - timedelta(days=7)
        return obj.actor_actions.filter(verb='access', timestamp__gte=time_delta).count()

    def get_topics(self, obj):
        return Topic.objects.filter(author=obj).count()

    def get_reactions(self, obj):
        return TopicLike.objects.filter(user=obj).count() + CommentLike.objects.filter(user=obj).count()

    def get_comments(self, obj):
        return Comment.objects.filter(author=obj).count()