import logging
import time
import json

from datetime import datetime
from notificationhelper import build_event_data
from util.jinjautil import get_template_env
from util.secscan.api import PRIORITY_LEVELS, get_priority_for_index

template_env = get_template_env("events")
logger = logging.getLogger(__name__)

class InvalidNotificationEventException(Exception):
  pass

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

  def get_level(self, event_data, notification_data):
    """
    Returns a 'level' representing the severity of the event.
    Valid values are: 'info', 'warning', 'error', 'primary', 'success'
    """
    raise NotImplementedError

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

  def get_message(self, event_data, notification_data):
    """
    Returns a human readable HTML message for the given notification data.
    """
    return template_env.get_template(self.event_name() + '.html').render({
      'event_data': event_data,
      'notification_data': notification_data
    })

  def get_sample_data(self, notification):
    """
    Returns sample data for testing the raising of this notification, with an example notification.
    """
    raise NotImplementedError

  def should_perform(self, event_data, notification_data):
    """
    Whether a notification for this event should be performed. By default returns True.
    """
    return True

  @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_level(self, event_data, notification_data):
    return 'primary'

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

  def get_sample_data(self, notification):
    return build_event_data(notification.repository, {
      'updated_tags': {'latest': 'someimageid', 'foo': 'anotherimage'},
      'pruned_image_count': 3
    })


def _build_summary(event_data):
  """ Returns a summary string for the build data found in the event data block. """
  summary = 'for repository %s [%s]' % (event_data['repository'], event_data['build_id'][0:7])
  return summary


class VulnerabilityFoundEvent(NotificationEvent):
  @classmethod
  def event_name(cls):
    return 'vulnerability_found'

  def get_level(self, event_data, notification_data):
    priority = event_data['vulnerability']['priority']
    if priority == 'Defcon1' or priority == 'Critical':
      return 'error'

    if priority == 'Medium' or priority == 'High':
      return 'warning'

    return 'info'

  def get_sample_data(self, notification):
    event_config = json.loads(notification.event_config_json)

    return build_event_data(notification.repository, {
      'tags': ['latest', 'prod'],
      'image': 'some-image-id',
      'vulnerability': {
        'id': 'CVE-FAKE-CVE',
        'description': 'A futurist vulnerability',
        'link': 'https://security-tracker.debian.org/tracker/CVE-FAKE-CVE',
        'priority': get_priority_for_index(event_config['level'])
      },
    })

  def should_perform(self, event_data, notification_data):
    event_config = json.loads(notification_data.event_config_json)
    expected_level_index = event_config['level']
    priority = PRIORITY_LEVELS[event_data['vulnerability']['priority']]
    actual_level_index = priority['index']
    return expected_level_index <= actual_level_index

  def get_summary(self, event_data, notification_data):
    msg = '%s vulnerability detected in repository %s in tags %s'
    return msg % (event_data['vulnerability']['priority'],
                  event_data['repository'],
                  ', '.join(event_data['tags']))


class BuildQueueEvent(NotificationEvent):
  @classmethod
  def event_name(cls):
    return 'build_queued'

  def get_level(self, event_data, notification_data):
    return 'info'

  def get_sample_data(self, notification):
    build_uuid = 'fake-build-id'

    return build_event_data(notification.repository, {
      'is_manual': False,
      'build_id': build_uuid,
      'build_name': 'some-fake-build',
      'docker_tags': ['latest', 'foo', 'bar'],
      'trigger_id': '1245634',
      'trigger_kind': 'GitHub',
      'trigger_metadata': {
        "default_branch": "master",
        "ref": "refs/heads/somebranch",
        "commit": "42d4a62c53350993ea41069e9f2cfdefb0df097d",
        "commit_info": {
          'url': 'http://path/to/the/commit',
          'message': 'Some commit message',
          'date': time.mktime(datetime.now().timetuple()),
          'author': {
            'username': 'fakeauthor',
            'url': 'http://path/to/fake/author/in/scm',
            'avatar_url': 'http://www.gravatar.com/avatar/fakehash'
          }
        }
      }
    }, subpage='/build/%s' % build_uuid)

  def get_summary(self, event_data, notification_data):
    return 'Build queued ' + _build_summary(event_data)


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

  def get_level(self, event_data, notification_data):
    return 'info'

  def get_sample_data(self, notification):
    build_uuid = 'fake-build-id'

    return build_event_data(notification.repository, {
      'build_id': build_uuid,
      'build_name': 'some-fake-build',
      'docker_tags': ['latest', 'foo', 'bar'],
      'trigger_id': '1245634',
      'trigger_kind': 'GitHub',
      'trigger_metadata': {
        "default_branch": "master",
        "ref": "refs/heads/somebranch",
        "commit": "42d4a62c53350993ea41069e9f2cfdefb0df097d"
      }
    }, subpage='/build/%s' % build_uuid)

  def get_summary(self, event_data, notification_data):
    return 'Build started ' + _build_summary(event_data)


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

  def get_level(self, event_data, notification_data):
    return 'success'

  def get_sample_data(self, notification):
    build_uuid = 'fake-build-id'

    return build_event_data(notification.repository, {
      'build_id': build_uuid,
      'build_name': 'some-fake-build',
      'docker_tags': ['latest', 'foo', 'bar'],
      'trigger_id': '1245634',
      'trigger_kind': 'GitHub',
      'trigger_metadata': {
        "default_branch": "master",
        "ref": "refs/heads/somebranch",
        "commit": "42d4a62c53350993ea41069e9f2cfdefb0df097d"
      },
      'image_id': '1245657346'
    }, subpage='/build/%s' % build_uuid)

  def get_summary(self, event_data, notification_data):
    return 'Build succeeded ' + _build_summary(event_data)


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

  def get_level(self, event_data, notification_data):
    return 'error'

  def get_sample_data(self, notification):
    build_uuid = 'fake-build-id'

    return build_event_data(notification.repository, {
      'build_id': build_uuid,
      'build_name': 'some-fake-build',
      'docker_tags': ['latest', 'foo', 'bar'],
      'trigger_kind': 'GitHub',
      'error_message': 'This is a fake error message',
      'trigger_id': '1245634',
      'trigger_kind': 'GitHub',
      'trigger_metadata': {
        "default_branch": "master",
        "ref": "refs/heads/somebranch",
        "commit": "42d4a62c53350993ea41069e9f2cfdefb0df097d",
        "commit_info": {
          'url': 'http://path/to/the/commit',
          'message': 'Some commit message',
          'date': time.mktime(datetime.now().timetuple()),
          'author': {
            'username': 'fakeauthor',
            'url': 'http://path/to/fake/author/in/scm',
            'avatar_url': 'http://www.gravatar.com/avatar/fakehash'
          }
        }
      }
    }, subpage='/build?current=%s' % build_uuid)

  def get_summary(self, event_data, notification_data):
    return 'Build failure ' + _build_summary(event_data)