# vim: tabstop=4 shiftwidth=4 softtabstop=4

# Copyright (c) 2013 TrilioData, Inc.
# All Rights Reserved.

"""RequestContext: context for requests that persist through all of workloadmgr."""

import copy
import uuid

from workloadmgr.openstack.common import local
from workloadmgr.openstack.common import log as logging
from workloadmgr.openstack.common import timeutils
from workloadmgr import policy


LOG = logging.getLogger(__name__)


def generate_request_id():
    return 'req-' + str(uuid.uuid4())


class RequestContext(object):
    """Security context and request information.

    Represents the user taking a given action within the system.

    """

    def __init__(self, user_id, project_id, is_admin=None, read_deleted="no",
                 roles=None, remote_address=None, timestamp=None,
                 request_id=None, auth_token=None, overwrite=True,
                 quota_class=None, **kwargs):
        """
        :param read_deleted: 'no' indicates deleted records are hidden, 'yes'
            indicates deleted records are visible, 'only' indicates that
            *only* deleted records are visible.

        :param overwrite: Set to False to ensure that the greenthread local
            copy of the index is not overwritten.

        :param kwargs: Extra arguments that might be present, but we ignore
            because they possibly came in from older rpc messages.
        """
        if kwargs:
            LOG.warn(_('Arguments dropped when creating context: %s') %
                     str(kwargs))

        self.user_id = user_id
        self.project_id = project_id
        self.roles = roles or []
        self.is_admin = is_admin
        if self.is_admin is None:
            self.is_admin = policy.check_is_admin(self.roles)
        elif self.is_admin and 'admin' not in self.roles:
            self.roles.append('admin')
        self.read_deleted = read_deleted
        self.remote_address = remote_address
        if not timestamp:
            timestamp = timeutils.utcnow()
        if isinstance(timestamp, str):
            timestamp = timeutils.parse_strtime(timestamp)
        self.timestamp = timestamp
        if not request_id:
            request_id = generate_request_id()
        self.request_id = request_id
        self.auth_token = auth_token
        self.quota_class = quota_class
        if overwrite or not hasattr(local.store, 'context'):
            self.update_store()

    def _get_read_deleted(self):
        return self._read_deleted

    def _set_read_deleted(self, read_deleted):
        if read_deleted not in ('no', 'yes', 'only'):
            raise ValueError(_("read_deleted can only be one of 'no', "
                               "'yes' or 'only', not %r") % read_deleted)
        self._read_deleted = read_deleted

    def _del_read_deleted(self):
        del self._read_deleted

    read_deleted = property(_get_read_deleted, _set_read_deleted,
                            _del_read_deleted)

    def update_store(self):
        local.store.context = self

    def to_dict(self):
        return {'user_id': self.user_id,
                'project_id': self.project_id,
                'is_admin': self.is_admin,
                'read_deleted': self.read_deleted,
                'roles': self.roles,
                'remote_address': self.remote_address,
                'timestamp': timeutils.strtime(self.timestamp),
                'request_id': self.request_id,
                'auth_token': self.auth_token,
                'quota_class': self.quota_class,
                'tenant': self.tenant,
                'user': self.user}

    @classmethod
    def from_dict(cls, values):
        return cls(**values)

    def elevated(self, read_deleted=None, overwrite=False):
        """Return a version of this context with admin flag set."""
        context = copy.copy(self)
        context.is_admin = True

        if 'admin' not in context.roles:
            context.roles.append('admin')

        if read_deleted is not None:
            context.read_deleted = read_deleted

        return context

    @property
    def tenant(self):
        return self.project_id

    @property
    def user(self):
        return self.user_id


def get_admin_context(read_deleted="no"):
    return RequestContext(user_id=None,
                          project_id=None,
                          is_admin=True,
                          read_deleted=read_deleted,
                          overwrite=False)