import logging

from hashlib import sha1

from concurrent.futures import ThreadPoolExecutor
from marketorestpython.client import MarketoClient

from util.asyncwrapper import AsyncExecutorWrapper, NullExecutor, NullExecutorCancelled

logger = logging.getLogger(__name__)


class LeadNotFoundException(Exception):
  pass


def build_error_callback(message_when_exception):
  def maybe_log_error(response_future):
    try:
      response_future.result()
    except NullExecutorCancelled:
      pass
    except Exception:
      logger.exception('User analytics: %s', message_when_exception)

  return maybe_log_error


class _MarketoAnalyticsClient(object):
  """ User analytics implementation which will report user changes to the
      Marketo API.
  """
  def __init__(self, marketo_client, munchkin_private_key, lead_source):
    """ Instantiate with the given marketorestpython.client, the Marketo
        Munchkin Private Key, and the Lead Source that we want to set when we
        create new lead records in Marketo.
    """
    self._marketo = marketo_client
    self._munchkin_private_key = munchkin_private_key
    self._lead_source = lead_source

  def _get_lead_metadata(self, given_name, family_name, company):
    metadata = {}
    if given_name:
      metadata['firstName'] = given_name

    if family_name:
      metadata['lastName'] = family_name

    if company:
      metadata['company'] = company

    return metadata

  def create_lead(self, email, username, given_name, family_name, company):
    lead_data = dict(
      email=email,
      Quay_Username__c=username,
      leadSource='Web - Product Trial',
      Lead_Source_Detail__c=self._lead_source,
    )

    lead_data.update(self._get_lead_metadata(given_name, family_name, company))

    self._marketo.create_update_leads(
      action='createOrUpdate',
      leads=[lead_data],
      asyncProcessing=True,
      lookupField='email',
    )

  def _find_leads_by_email(self, email):
    # Fetch the existing user from the database by email
    found = self._marketo.get_multiple_leads_by_filter_type(
      filterType='email',
      filterValues=[email],
    )

    if not found:
      raise LeadNotFoundException('No lead found with email: {}'.format(email))

    return found

  def change_email(self, old_email, new_email):
    found = self._find_leads_by_email(old_email)

    # Update using their user id.
    updated = [dict(id=lead['id'], email=new_email) for lead in found]
    self._marketo.create_update_leads(
      action='updateOnly',
      leads=updated,
      asyncProcessing=True,
      lookupField='id',
    )

  def change_metadata(self, email, given_name, family_name, company):
    lead_data = self._get_lead_metadata(given_name, family_name, company)
    if not lead_data:
      return

    # Update using their email address.
    lead_data['email'] = email
    self._marketo.create_update_leads(
      action='updateOnly',
      leads=[lead_data],
      asyncProcessing=True,
      lookupField='email',
    )

  def change_username(self, email, new_username):
    # Update using their email.
    self._marketo.create_update_leads(
      action='updateOnly',
      leads=[{
        'email': email,
        'Quay_Username__c': new_username,
      }],
      asyncProcessing=True,
      lookupField='email',
    )

  @AsyncExecutorWrapper.sync
  def get_user_analytics_metadata(self, user_obj):
    """ Return a list of properties that should be added to the user object to allow
        analytics associations.
    """
    if not self._munchkin_private_key:
      return dict()

    marketo_user_hash = sha1(self._munchkin_private_key)
    marketo_user_hash.update(user_obj.email)

    return dict(
      marketo_user_hash=marketo_user_hash.hexdigest(),
    )


class UserAnalytics(object):
  def __init__(self, app=None):
    self.app = app
    if app is not None:
      self.state = self.init_app(app)
    else:
      self.state = None

  def init_app(self, app):
    analytics_type = app.config.get('USER_ANALYTICS_TYPE', 'FakeAnalytics')

    marketo_munchkin_id = ''
    marketo_munchkin_private_key = ''
    marketo_client_id = ''
    marketo_client_secret = ''
    marketo_lead_source = ''
    executor = NullExecutor()

    if analytics_type == 'Marketo':
      marketo_munchkin_id = app.config['MARKETO_MUNCHKIN_ID']
      marketo_munchkin_private_key = app.config['MARKETO_MUNCHKIN_PRIVATE_KEY']
      marketo_client_id = app.config['MARKETO_CLIENT_ID']
      marketo_client_secret = app.config['MARKETO_CLIENT_SECRET']
      marketo_lead_source = app.config['MARKETO_LEAD_SOURCE']

      logger.debug('Initializing marketo with keys: %s %s %s', marketo_munchkin_id,
                   marketo_client_id, marketo_client_secret)

      executor = ThreadPoolExecutor(max_workers=1)

    marketo_client = MarketoClient(marketo_munchkin_id, marketo_client_id, marketo_client_secret)
    client_wrapper = _MarketoAnalyticsClient(marketo_client, marketo_munchkin_private_key,
                                             marketo_lead_source)
    user_analytics = AsyncExecutorWrapper(client_wrapper, executor)

    # register extension with app
    app.extensions = getattr(app, 'extensions', {})
    app.extensions['user_analytics'] = user_analytics
    return user_analytics

  def __getattr__(self, name):
    return getattr(self.state, name, None)