import logging
import json

from data import model

logger = logging.getLogger(__name__)


MAX_TEAMS_PER_ITERATION = 500


def sync_teams_to_groups(authentication, stale_cutoff):
  """ Performs team syncing by looking up any stale team(s) found, and performing the sync
      operation on them.
  """
  logger.debug('Looking up teams to sync to groups')

  sync_team_tried = set()
  while len(sync_team_tried) < MAX_TEAMS_PER_ITERATION:
    # Find a stale team.
    stale_team_sync = model.team.get_stale_team(stale_cutoff)
    if not stale_team_sync:
      logger.debug('No additional stale team found; sleeping')
      return

    # Make sure we don't try to reprocess a team on this iteration.
    if stale_team_sync.id in sync_team_tried:
      break

    sync_team_tried.add(stale_team_sync.id)

    # Sync the team.
    sync_successful = sync_team(authentication, stale_team_sync)
    if not sync_successful:
      return


def sync_team(authentication, stale_team_sync):
  """ Performs synchronization of a team (as referenced by the TeamSync stale_team_sync).
      Returns True on success and False otherwise.
  """
  sync_config = json.loads(stale_team_sync.config)
  logger.info('Syncing team `%s` under organization %s via %s (#%s)', stale_team_sync.team.name,
              stale_team_sync.team.organization.username, sync_config, stale_team_sync.team_id,
              extra={'team': stale_team_sync.team_id, 'sync_config': sync_config})

  # Load all the existing members of the team in Quay that are bound to the auth service.
  existing_users = model.team.get_federated_team_member_mapping(stale_team_sync.team,
                                                                authentication.federated_service)

  logger.debug('Existing membership of %s for team `%s` under organization %s via %s (#%s)',
               len(existing_users), stale_team_sync.team.name,
               stale_team_sync.team.organization.username, sync_config, stale_team_sync.team_id,
               extra={'team': stale_team_sync.team_id, 'sync_config': sync_config,
                      'existing_member_count': len(existing_users)})

  # Load all the members of the team from the authenication system.
  (member_iterator, err) = authentication.iterate_group_members(sync_config)
  if err is not None:
    logger.error('Got error when trying to iterate group members with config %s: %s',
                 sync_config, err)
    return False

  # Collect all the members currently found in the group, adding them to the team as we go
  # along.
  group_membership = set()
  for (member_info, err) in member_iterator:
    if err is not None:
      logger.error('Got error when trying to construct a member: %s', err)
      continue

    # If the member is already in the team, nothing more to do.
    if member_info.username in existing_users:
      logger.debug('Member %s already in team `%s` under organization %s via %s (#%s)',
                   member_info.username, stale_team_sync.team.name,
                   stale_team_sync.team.organization.username, sync_config,
                   stale_team_sync.team_id,
                   extra={'team': stale_team_sync.team_id, 'sync_config': sync_config,
                          'member': member_info.username})

      group_membership.add(existing_users[member_info.username])
      continue

    # Retrieve the Quay user associated with the member info.
    (quay_user, err) = authentication.get_and_link_federated_user_info(member_info,
                                                                       internal_create=True)
    if err is not None:
      logger.error('Could not link external user %s to an internal user: %s',
                   member_info.username, err,
                   extra={'team': stale_team_sync.team_id, 'sync_config': sync_config,
                          'member': member_info.username, 'error': err})
      continue

    # Add the user to the membership set.
    group_membership.add(quay_user.id)

    # Add the user to the team.
    try:
      logger.info('Adding member %s to team `%s` under organization %s via %s (#%s)',
                  quay_user.username, stale_team_sync.team.name,
                  stale_team_sync.team.organization.username, sync_config,
                  stale_team_sync.team_id,
                  extra={'team': stale_team_sync.team_id, 'sync_config': sync_config,
                         'member': quay_user.username})

      model.team.add_user_to_team(quay_user, stale_team_sync.team)
    except model.UserAlreadyInTeam:
      # If the user is already present, nothing more to do for them.
      pass

  # Update the transaction and last_updated time of the team sync. Only if it matches
  # the current value will we then perform the deletion step.
  got_transaction_handle = model.team.update_sync_status(stale_team_sync)
  if not got_transaction_handle:
    # Another worker updated this team. Nothing more to do.
    logger.debug('Another worker synced team `%s` under organization %s via %s (#%s)',
                 stale_team_sync.team.name,
                 stale_team_sync.team.organization.username, sync_config,
                 stale_team_sync.team_id,
                 extra={'team': stale_team_sync.team_id, 'sync_config': sync_config})
    return True

  # Delete any team members not found in the backing auth system.
  logger.debug('Deleting stale members for team `%s` under organization %s via %s (#%s)',
               stale_team_sync.team.name, stale_team_sync.team.organization.username,
               sync_config, stale_team_sync.team_id,
               extra={'team': stale_team_sync.team_id, 'sync_config': sync_config})

  deleted = model.team.delete_members_not_present(stale_team_sync.team, group_membership)

  # Done!
  logger.info('Finishing sync for team `%s` under organization %s via %s (#%s): %s deleted',
              stale_team_sync.team.name, stale_team_sync.team.organization.username,
              sync_config, stale_team_sync.team_id, deleted,
              extra={'team': stale_team_sync.team_id, 'sync_config': sync_config})
  return True