import logging

from functools import wraps

from cnr.exception import UnauthorizedAccess
from flask import Blueprint

from app import metric_queue
from auth.permissions import (AdministerRepositoryPermission, ReadRepositoryPermission,
                              ModifyRepositoryPermission)
from data import model # TODO: stop using model directly
from util.metrics.metricqueue import time_blueprint


appr_bp = Blueprint('appr', __name__)
time_blueprint(appr_bp, metric_queue)
logger = logging.getLogger(__name__)


def _raise_unauthorized(repository, scopes):
  raise StandardError("Unauthorized acces to %s", repository)


def _get_reponame_kwargs(*args, **kwargs):
  return [kwargs['namespace_name'], kwargs['repo_name']]


def require_repo_permission(permission_class, scopes=None, allow_public=False,
                            raise_method=_raise_unauthorized,
                            get_reponame_method=_get_reponame_kwargs):
  def wrapper(func):
    @wraps(func)
    def wrapped(*args, **kwargs):
      namespace_name, repo_name = get_reponame_method(*args, **kwargs)

      logger.debug('Checking permission %s for repo: %s/%s', permission_class,
                   namespace_name, repo_name)
      permission = permission_class(namespace_name, repo_name)
      if (permission.can() or
          (allow_public and
           model.repository.repository_is_public(namespace_name, repo_name))):
        return func(*args, **kwargs)
      repository = namespace_name + '/' + repo_name
      raise_method(repository, scopes)
    return wrapped
  return wrapper


def _raise_method(repository, scopes):
  raise UnauthorizedAccess("Unauthorized access for: %s" % repository,
                           {"package": repository, "scopes": scopes})


def _get_reponame_kwargs(*args, **kwargs):
  return [kwargs['namespace'], kwargs['package_name']]


require_app_repo_read = require_repo_permission(ReadRepositoryPermission,
                                                scopes=['pull'],
                                                allow_public=True,
                                                raise_method=_raise_method,
                                                get_reponame_method=_get_reponame_kwargs)

require_app_repo_write = require_repo_permission(ModifyRepositoryPermission,
                                                 scopes=['pull', 'push'],
                                                 raise_method=_raise_method,
                                                 get_reponame_method=_get_reponame_kwargs)

require_app_repo_admin = require_repo_permission(AdministerRepositoryPermission,
                                                 scopes=['pull', 'push'],
                                                 raise_method=_raise_method,
                                                 get_reponame_method=_get_reponame_kwargs)