# Copyright 2015 The Chromium Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

"""URI endpoint for nudging Anomaly entities and updating alert bug IDs."""

import json

from google.appengine.api import users
from google.appengine.ext import ndb

from dashboard import request_handler
from dashboard import utils
from dashboard import xsrf


class EditAnomaliesHandler(request_handler.RequestHandler):
  """Handles editing the bug IDs and revision range of Alerts."""

  @xsrf.TokenRequired
  def post(self):
    """Allows adding or resetting bug IDs and invalid statuses to Alerts.

    Additionally, this endpoint is also responsible for changing the start
    and end revisions of Anomaly entities.

    Request parameters:
      keys: A comma-separated list of urlsafe keys of Anomaly entities.
      bug_id: The new bug ID. This should be either the string REMOVE
          (indicating resetting the bug ID to None), or an integer. A negative
          integer indicates an invalid or ignored alert. If this is given, then
          the start and end revision ranges are ignored.
      new_start_revision: New start revision value for the alert.
      new_end_revision: New end revision value for the alert.

    Outputs:
      JSON which indicates the result. If an error has occurred, the field
      "error" should be in the result. If successful, the response is still
      expected to be JSON.
    """
    if not utils.IsValidSheriffUser():
      user = users.get_current_user()
      self.ReportError('User "%s" not authorized.' % user, status=403)
      return

    # Get the list of alerts to modify.
    urlsafe_keys = self.request.get('keys')
    if not urlsafe_keys:
      self.response.out.write(json.dumps({
          'error': 'No alerts specified to add bugs to.'}))
      return
    keys = [ndb.Key(urlsafe=k) for k in urlsafe_keys.split(',')]
    alert_entities = ndb.get_multi(keys)

    # Get the parameters which specify the changes to make.
    bug_id = self.request.get('bug_id')
    new_start_revision = self.request.get('new_start_revision')
    new_end_revision = self.request.get('new_end_revision')
    if bug_id:
      self.ChangeBugId(alert_entities, bug_id)
    elif new_start_revision and new_end_revision:
      self.NudgeAnomalies(alert_entities, new_start_revision, new_end_revision)
    else:
      self.response.out.write(
          json.dumps({'error': 'No bug ID or new revision specified.'}))

  def ChangeBugId(self, alert_entities, bug_id):
    """Changes or resets the bug ID of all given alerts."""
    # Change the bug ID if a new bug ID is specified and valid.
    if bug_id == 'REMOVE':
      bug_id = None
    else:
      try:
        bug_id = int(bug_id)
      except ValueError:
        self.response.out.write(json.dumps({
            'error': 'Invalid bug ID %s' % str(bug_id)}))
        return
    for a in alert_entities:
      a.bug_id = bug_id

    ndb.put_multi(alert_entities)
    self.response.out.write(json.dumps({'bug_id': bug_id}))

  def NudgeAnomalies(self, anomaly_entities, start, end):
    # Change the revision range if a new revision range is specified and valid.
    try:
      start = int(start)
      end = int(end)
    except ValueError:
      self.response.out.write(
          json.dumps({'error': 'Invalid revisions %s, %s' % (start, end)}))
      return
    for a in anomaly_entities:
      a.start_revision = start
      a.end_revision = end

    ndb.put_multi(anomaly_entities)
    self.response.out.write(json.dumps({'success': 'Alerts nudged.'}))