###############################################################################
# RENDERERS

from rest_framework import renderers
from rest_framework.utils import encoders
import json


class JSONEncoder(encoders.JSONEncoder):
    """
    Im defining our own json encoder here in order to be able to encode
    datatime and django countryfields.

    Im making the munge renderer use this encoder to encode json, this approach
    may need to be tidied up a bit.
    """

    def default(self, obj):
        """Default JSON serializer."""
        import datetime
        import django_countries.fields

        if isinstance(obj, datetime.datetime):
            return obj.isoformat()

        if isinstance(obj, django_countries.fields.Country):
            return str(obj)

        return encoders.JSONEncoder.default(self, obj)


class MungeRenderer(renderers.BaseRenderer):
    media_type = 'text/plain'
    format = 'txt'
    charset = 'iso-8859-1'

    def render(self, data, media_type=None, renderer_context=None):
        # TODO use munge:
        indent = None
        if 'request' in renderer_context:
            request = renderer_context.get('request')
            if "pretty" in request.GET:
                indent = 2
        return json.dumps(data, cls=JSONEncoder, indent=indent)


class MetaJSONRenderer(MungeRenderer):
    """
    Renderer which serializes to JSON.
    Does *not* apply JSON's character escaping for non-ascii characters.
    """
    ensure_ascii = False

    media_type = "application/json"
    format = "json"

    def render(self, data, accepted_media_type=None, renderer_context=None):
        """
        Tweak output rendering and pass to parent
        """

        if data is None:
            return bytes()

        result = {}

        if '__meta' in data:
            meta = data.pop('__meta')
        else:
            meta = dict()

        if 'request' in renderer_context:
            request = renderer_context.get('request')
            meta.update(getattr(request, 'meta_response', {}))

        res = renderer_context['response']
        if res.status_code < 400:
            if 'results' in data:
                result['data'] = data.pop('results')
            elif data:
                if isinstance(data, dict):
                    result["data"] = [data]
                else:
                    result["data"] = [r for r in data if r is not None]
            else:
                result["data"] = []

        elif res.status_code < 500:
            meta['error'] = data.pop('detail', 'Unknown')
            result.update(**data)

        result['meta'] = meta

        return super(self.__class__, self).render(result, accepted_media_type,
                                                  renderer_context)