import logging
import io
import os.path
import tarfile
import base64

logger = logging.getLogger(__name__)

class InvalidNotificationEventException(Exception):
  pass

class NotificationEvent(object):
  def __init__(self):
    pass

  def get_summary(self, notification_data):
    """
    Returns a human readable one-line summary for the given notification data.
    """
    raise NotImplementedError

  def get_message(self, notification_data):
    """
    Returns a human readable HTML message for the given notification data.
    """
    raise NotImplementedError

  def get_sample_data(self, repository=None):
    """
    Returns sample data for testing the raising of this notification, with an optional
    repository.
    """
    raise NotImplementedError

  @classmethod
  def event_name(cls):
    """
    Particular event implemented by subclasses.
    """
    raise NotImplementedError

  @classmethod
  def get_event(cls, eventname):
    for subc in cls.__subclasses__():
      if subc.event_name() == eventname:
        return subc()

    raise InvalidNotificationEventException('Unable to find event: %s' % eventname)


class RepoPushEvent(NotificationEvent):
  @classmethod
  def event_name(cls):
    return 'repo_push'

  def get_summary(self, notification_data):
    return 'Repository %s updated' % (event_data['repository'])

  def get_message(self, notification_data):
    event_data = notification_data['event_data']
    if not event_data['tags']:
      return  '%s images pushed for repository %s (%s)' % (event_data['pushed_image_count'],
                                                           event_data['repository'], event_data['homepage'])

    return 'Tags %s updated for repository %s (%s)' % (event_data['updated_tags'],
                                                       event_data['repository'], event_data['homepage'])

  def get_sample_data(self, repository=None):
    repo_string = '%s/%s' % (repository.namespace, repository.name)
    event_data = {
      'repository': repo_string,
      'namespace': repository.namespace,
      'name': repository.name,
      'docker_url': 'quay.io/%s' % repo_string,
      'homepage': 'https://quay.io/repository/%s' % repo_string,
      'visibility': repository.visibility.name,
      'updated_tags': ['latest', 'foo', 'bar'],
      'pushed_image_count': 10,
      'pruned_image_count': 3
    }
    return event_data


class BuildStartEvent(NotificationEvent):
  @classmethod
  def event_name(cls):
    return 'build_start'

  def get_sample_data(repository=None):
    pass


class BuildSuccessEvent(NotificationEvent):
  @classmethod
  def event_name(cls):
    return 'build_success'

  def get_sample_data(repository=None):
    pass


class BuildFailureEvent(NotificationEvent):
  @classmethod
  def event_name(cls):
    return 'build_failure'

  def get_sample_data(repository=None):
    pass