# -*- coding: utf-8 -*-
import logging
from django.apps import apps
from django.core.exceptions import ImproperlyConfigured
from django.core.mail import EmailMessage
from django.template.loader import get_template

app_config = apps.get_containing_app_config(__package__)
logger = logging.getLogger(__name__)


class AbstractMail(object):
    _subject = u''
    _template_name = None

    def _get_sender(self):
        #app_config = apps.get_containing_app_config(__package__)
        return app_config.settings.email_sender

    def _get_subject(self, subject_fmt=None, **kwargs):
        if subject_fmt is None:
            subject_fmt = self._subject
        #app_config = apps.get_containing_app_config(__package__)
        if app_config.settings.email_subject_prefix:
            subject_fmt = u'%s %s' % (app_config.settings.email_subject_prefix, subject_fmt)
        subject = subject_fmt.format(**kwargs)
        return subject

    def _get_template(self):
        if not self._template_name:
            raise ImproperlyConfigured('%s._template_name ist not set.', self.__class__.__name__)
        return get_template(self._template_name, using='PLAINTEXT')

    def _get_context_data(self, extra_context=None):
        #app_config = apps.get_containing_app_config(__package__)
        context = {
            'base_url': app_config.settings.email_base_url,
        }
        if extra_context:
            context.update(extra_context)
        return context

    def _get_body(self, context=None):
        template = self._get_template()
        context = self._get_context_data(extra_context=context)
        return template.render(context)

    def _get_recipients(self):
        raise NotImplementedError()

    def send(self):
        subject = self._get_subject()
        body = self._get_body()
        sender = self._get_sender()
        recipients = self._get_recipients()

        email = EmailMessage(subject=subject, body=body, from_email=sender, to=recipients)
        logger.info(u'Send %s to %s', self.__class__.__name__, recipients)
        email.send()