#!/usr/bin/env python3
# Copyright (C) 2020 The Android Open Source Project
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#      http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

import os
import subprocess
import sys
import tempfile
import time
from typing import List, Optional
from urllib import request, error

from perfetto.common.exceptions import PerfettoException
from perfetto.trace_processor.platform import PlatformDelegate

# Default port that trace_processor_shell runs on
TP_PORT = 9001


def load_shell(bin_path: str,
               unique_port: bool,
               verbose: bool,
               ingest_ftrace_in_raw: bool,
               enable_dev_features: bool,
               platform_delegate: PlatformDelegate,
               load_timeout: int = 2,
               extra_flags: Optional[List[str]] = None):
  addr, port = platform_delegate.get_bind_addr(
      port=0 if unique_port else TP_PORT)
  url = f'{addr}:{str(port)}'

  shell_path = platform_delegate.get_shell_path(bin_path=bin_path)
  if os.name == 'nt' and not shell_path.endswith('.exe'):
    tp_exec = [sys.executable, shell_path]
  else:
    tp_exec = [shell_path]

  args = ['-D', '--http-port', str(port)]
  if not ingest_ftrace_in_raw:
    args.append('--no-ftrace-raw')

  if enable_dev_features:
    args.append('--dev')

  if extra_flags:
    args.extend(extra_flags)

  temp_stdout = tempfile.TemporaryFile()
  temp_stderr = tempfile.TemporaryFile()
  p = subprocess.Popen(
      tp_exec + args,
      stdin=subprocess.DEVNULL,
      stdout=temp_stdout,
      stderr=None if verbose else temp_stderr)

  success = False
  for _ in range(load_timeout + 1):
    try:
      if p.poll() is None:
        _ = request.urlretrieve(f'http://{url}/status')
        success = True
      break
    except (error.URLError, ConnectionError):
      time.sleep(1)

  if not success:
    p.kill()
    temp_stdout.seek(0)
    stdout = temp_stdout.read().decode("utf-8")
    temp_stderr.seek(0)
    stderr = temp_stderr.read().decode("utf-8")
    raise PerfettoException("Trace processor failed to start.\n"
                            f"stdout: {stdout}\nstderr: {stderr}\n")

  return url, p