import pytz
from collections import Mapping, OrderedDict

from django.db import models
from django.shortcuts import resolve_url
from django.contrib.sites.models import Site
from django.utils import timezone

from rest_framework import serializers
from rest_framework.decorators import api_view, throttle_classes
from rest_framework.response import Response
from rest_framework.utils import representation
from rest_framework.utils.serializer_helpers import ReturnDict

from events.models import Event, Place, Team


def localized_time(dt, tz='UTC'):
    event_tz = pytz.timezone(tz)
    print("Searchable timezone: %s" % tz)
    return dt.astimezone(event_tz).strftime("%Y-%m-%dT%H:%M:%S%z")


class CollectionSerializer(serializers.ListSerializer):
    def to_representation(self, data):
        """
        List of object instances -> List of dicts of primitive datatypes.
        """
        # Dealing with nested relationships, data can be a Manager,
        # so, first get a queryset from the Manager if needed
        iterable = data.all() if isinstance(data, models.Manager) else data

        repr_data = OrderedDict({
            "@context": "https://www.w3.org/ns/activitystreams",
            "summary": self.child.verbose_name_plural,
            "type": "Collection",
            "totalItems": len(iterable),
            "items": [self.child.to_representation(item) for item in iterable],
        })
        repr_data.move_to_end('@context', last=False)
        repr_data.move_to_end('items')
        return repr_data

    @property
    def data(self):
        ret = super(serializers.ListSerializer, self).data
        return ReturnDict(ret, serializer=self)


class APGroupSerializer(serializers.ModelSerializer):
    verbose_name_plural = 'Groups'

    context = serializers.CharField(label='context', default='https://www.w3.org/ns/activitystreams')
    type = serializers.CharField(label='type', default='Group')
    id = serializers.CharField(source='get_absolute_url')
    name = serializers.CharField(source='__str__')
    url = serializers.CharField(source='web_url')

    class Meta:
        list_serializer_class = CollectionSerializer
        model = Team
        fields = ('context', 'type', 'id', 'name', 'url')

    def to_representation(self, instance):
        data = super(APGroupSerializer, self).to_representation(instance)
        data['@context'] = data['context']
        del data['context']
        data.move_to_end('@context', last=False)

        data['id'] = 'http://%s%s' % (Site.objects.get_current().domain, data['id'])
        return data


class APPlaceSerializer(serializers.ModelSerializer):
    verbose_name_plural = 'Places'

    context = serializers.CharField(label='context', default='https://www.w3.org/ns/activitystreams')
    type = serializers.CharField(label='type', default='Place')
    id = serializers.CharField(source='get_absolute_url')
    name = serializers.CharField(source='__str__')
    latitude = serializers.DecimalField(max_digits=10, decimal_places=5)
    longitude = serializers.DecimalField(max_digits=10, decimal_places=5)
    url = serializers.URLField(source='place_url')

    class Meta:
        list_serializer_class = CollectionSerializer
        model = Place
        fields = ('context', 'type', 'id', 'name', 'latitude', 'longitude', 'url')

    def to_representation(self, instance):
        data = super(APPlaceSerializer, self).to_representation(instance)
        data['@context'] = data['context']
        del data['context']
        data.move_to_end('@context', last=False)

        data['id'] = 'http://%s%s' % (Site.objects.get_current().domain, data['id'])
        return data


class APEventSerializer(serializers.ModelSerializer):
    verbose_name_plural = 'Events'

    context = serializers.CharField( default='https://www.w3.org/ns/activitystreams')
    type = serializers.CharField(default='Event')
    id = serializers.CharField(source='get_absolute_url')
    name = serializers.CharField()
    attributedTo = APGroupSerializer(source='team')
    location = APPlaceSerializer(source='place')
    startTime = serializers.DateTimeField(source='start_time')
    endTime = serializers.DateTimeField(source='end_time')
    image = serializers.URLField(source='team.card_img_url')
    url = serializers.URLField(source='web_url')
    published = serializers.DateTimeField(source='created_time')

    class Meta:
        list_serializer_class = CollectionSerializer
        model = Event
        fields = ('context', 'type', 'id', 'name', 'startTime', 'endTime', 'attributedTo', 'location', 'image', 'url', 'published')

    def to_representation(self, instance):
        data = super(APEventSerializer, self).to_representation(instance)
        data['@context'] = data['context']
        del data['context']
        data.move_to_end('@context', last=False)

        if data['image'].startswith('/'):
            data['image'] = '/'.join(data['id'].split('/')[:3]) + data['image']

        data['id'] = 'http://%s%s' % (Site.objects.get_current().domain, data['id'])
        return data

@api_view(['GET'])
def events_list(request):
    serializer = APEventSerializer(Event.objects.filter(end_time__gte=timezone.now()), many=True)
    return Response(serializer.data)

@api_view(['GET'])
def places_list(request):
    serializer = APPlaceSerializer(Place.objects.all(), many=True)
    return Response(serializer.data)