import json
import requests
import logging

from github import Github

from app import app


user_files = app.config['USERFILES']


logger = logging.getLogger(__name__)


ZIPBALL = 'application/zip'


class BuildArchiveException(Exception):
  pass


class InvalidServiceException(Exception):
  pass


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

  def list_repositories(self, auth_token):
    """
    Take the auth information for the specific trigger type and load the
    list of repositories.
    """
    raise NotImplementedError

  def incoming_webhook(self, request, auth_token, config):
    """
    Transform the incoming request data into a set of actions.
    """
    raise NotImplementedError

  @classmethod
  def service_name(cls):
    """
    Particular service implemented by subclasses.
    """
    raise NotImplementedError

  @classmethod
  def get_trigger_for_service(cls, service):
    for subc in cls.__subclasses__():
      if subc.service_name() == service:
        return subc()

    raise InvalidServiceException('Unable to find service: %s' % service)


class GithubBuildTrigger(BuildTrigger):
  @staticmethod
  def _get_client(auth_token):
    return Github(auth_token, client_id=app.config['GITHUB_CLIENT_ID'],
                  client_secret=app.config['GITHUB_CLIENT_SECRET'])

  @classmethod
  def service_name(cls):
    return 'github'

  def list_repositories(self, auth_token):
    gh_client = self._get_client(auth_token)
    usr = gh_client.get_user()

    repo_list = [repo.full_name for repo in usr.get_repos()]
    for org in usr.get_orgs():
      repo_list.extend((repo.full_name for repo in org.get_repos()))

    return repo_list

  def incoming_webhook(self, request, auth_token, config):
    payload = request.get_json()
    logger.debug('Payload %s', payload)
    ref = payload['ref']
    commit_id = payload['head_commit']['id'][0:7]

    gh_client = self._get_client(auth_token)

    repo_full_name = '%s/%s' % (payload['repository']['owner']['name'],
                                payload['repository']['name'])
    repo = gh_client.get_repo(repo_full_name)

    logger.debug('Github repo: %s', repo)

    # Prepare the download and upload URLs
    branch_name = ref.split('/')[-1]
    archive_link = repo.get_archive_link('zipball', branch_name)
    download_archive = requests.get(archive_link, stream=True)

    upload_url, dockerfile_id = user_files.prepare_for_drop(ZIPBALL)
    up_headers = {'Content-Type': ZIPBALL}
    upload_archive = requests.put(upload_url, headers=up_headers,
                                  data=download_archive.raw)

    if upload_archive.status_code / 100 != 2:
      logger.debug('Failed to upload archive to s3')
      raise BuildArchiveException('Unable to copy archie to s3 for ref: %s' %
                                  ref)

    logger.debug('Successfully prepared job')

    return dockerfile_id, branch_name, commit_id