#!/usr/bin/env python
# Copyright (c) 2019 The WebRTC project authors. All Rights Reserved.
#
# Use of this source code is governed by a BSD-style license
# that can be found in the LICENSE file in the root of the source
# tree. An additional intellectual property rights grant can be found
# in the file PATENTS.  All contributing project authors may
# be found in the AUTHORS file in the root of the source tree.

"""Converts and uploads results to the Chrome perf dashboard.

This conversion step is needed because test/testsupport/perf_test.cc can't
output histograms natively. There is, unfortunately, no C++ API for histograms.
This script is in python so it can depend on Catapult's python API instead.
See histogram_util.py for how this is done. We should move to the C++ API and
delete the scripts in this dir as soon as there is a C++ API (less conversions =
easier to understand).

This script can't be in recipes, because we can't access the catapult APIs from
there. It needs to be here source-side.

This script is adapted from the downstream variant like this:
  * Follows upstream naming conventions.
  * Downstream-only parameters and concepts go away.
  * oAuth tokens are generated by luci-auth.
"""

import argparse
import httplib2
import json
import sys
import subprocess
import zlib

import histogram_util


def _GenerateOauthToken():
  args = ['luci-auth', 'token']
  p = subprocess.Popen(args, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
  if p.wait() == 0:
    output = p.stdout.read()
    return output.strip()
  else:
    raise RuntimeError(
        'Error generating authentication token.\nStdout: %s\nStderr:%s' %
        (p.stdout.read(), p.stderr.read()))


def _SendHistogramSetJson(url, histogram_json, oauth_token):
  """Make a HTTP POST with the given JSON to the Performance Dashboard.

  Args:
    url: URL of Performance Dashboard instance, e.g.
        "https://chromeperf.appspot.com".
    histogram_json: a JSON object that contains the data to be sent.
    oauth_token: An oauth token to use for authorization.
  """
  headers = {'Authorization': 'Bearer %s' % oauth_token}
  serialized = json.dumps(histogram_json.AsDicts(), indent=4)
  data = zlib.compress(serialized)

  http = httplib2.Http()
  response, content = http.request(url + '/add_histograms', method='POST',
                                   body=data, headers=headers)
  return response, content


def _LoadHistogramSetJson(options):
  with options.input_results_file as f:
    json_data = json.load(f)

  histograms = histogram_util.LoadHistograms(json_data)
  hs = histogram_util.MakeWebRtcHistogramSet(
      stats=histograms,
      commit_pos=options.commit_position,
      commit_hash=options.webrtc_git_hash,
      master=options.perf_dashboard_machine_group,
      bot=options.bot,
      test_suite=options.test_suite,
      build_url=options.build_page_url)

  return hs


def _CreateParser():
  parser = argparse.ArgumentParser()
  parser.add_argument('--perf-dashboard-machine-group', required=True,
                      help='The "master" the bots are grouped under. This '
                           'string is the group in the the perf dashboard path '
                            'group/bot/perf_id/metric/subtest.')
  parser.add_argument('--bot', required=True,
                      help='The bot running the test (e.g. '
                           'webrtc-win-large-tests).')
  parser.add_argument('--test-suite', required=True,
                      help='The key for the test in the dashboard (i.e. what '
                      'you select in the top-level test suite selector in the '
                      'dashboard')
  parser.add_argument('--webrtc-git-hash', required=True,
                      help='webrtc.googlesource.com commit hash.')
  parser.add_argument('--commit-position', type=int, required=True,
                      help='Commit pos corresponding to the git hash.')
  parser.add_argument('--build-page-url', required=True,
                      help='URL to the build page for this build.')
  parser.add_argument('--dashboard-url', required=True,
                      help='Which dashboard to use.')
  parser.add_argument('--input-results-file', type=argparse.FileType(),
                      required=True,
                      help='A JSON file with output from WebRTC tests.')
  parser.add_argument('--output-json-file', type=argparse.FileType('w'),
                      help='Where to write the output (for debugging).')
  return parser


def main(args):
  parser = _CreateParser()
  options = parser.parse_args(args)

  histogram_json = _LoadHistogramSetJson(options)

  if options.output_json_file:
    with options.output_json_file as output_file:
      json.dump(histogram_json.AsDicts(), output_file, indent=4)

  oauth_token = _GenerateOauthToken()
  response, content = _SendHistogramSetJson(
      options.dashboard_url, histogram_json, oauth_token)

  if response.status == 200:
    return 0
  else:
    print("Upload failed with %d: %s\n\n%s" % (response.status, response.reason,
                                               content))
    return 1


if __name__ == '__main__':
  sys.exit(main(sys.argv[1:]))