# Copyright 2015-2018, Damian Johnson and The Tor Project
# See LICENSE for licensing information

"""
Interactive interpreter for interacting with Tor directly. This adds usability
features such as tab completion, history, and IRC-style functions (like /help).
"""

import os
import sys

import stem
import stem.connection
import stem.prereq
import stem.process
import stem.util.conf
import stem.util.system
import stem.util.term

from stem.util.term import Attr, Color, format

__all__ = [
  'arguments',
  'autocomplete',
  'commands',
  'help',
]

PROMPT = format('>>> ', Color.GREEN, Attr.BOLD, Attr.READLINE_ESCAPE)

STANDARD_OUTPUT = (Color.BLUE, Attr.LINES)
BOLD_OUTPUT = (Color.BLUE, Attr.BOLD, Attr.LINES)
HEADER_OUTPUT = (Color.GREEN, Attr.LINES)
HEADER_BOLD_OUTPUT = (Color.GREEN, Attr.BOLD, Attr.LINES)
ERROR_OUTPUT = (Attr.BOLD, Color.RED, Attr.LINES)

settings_path = os.path.join(os.path.dirname(__file__), 'settings.cfg')
uses_settings = stem.util.conf.uses_settings('stem_interpreter', settings_path)


@uses_settings
def msg(message, config, **attr):
  return config.get(message).format(**attr)


def main():
  import readline

  import stem.interpreter.arguments
  import stem.interpreter.autocomplete
  import stem.interpreter.commands

  try:
    args = stem.interpreter.arguments.parse(sys.argv[1:])
  except ValueError as exc:
    print(exc)
    sys.exit(1)

  if args.print_help:
    print(stem.interpreter.arguments.get_help())
    sys.exit()

  if args.disable_color or not sys.stdout.isatty():
    global PROMPT
    stem.util.term.DISABLE_COLOR_SUPPORT = True
    PROMPT = '>>> '

  # If the user isn't connecting to something in particular then offer to start
  # tor if it isn't running.

  if not (args.user_provided_port or args.user_provided_socket):
    is_tor_running = stem.util.system.is_running('tor') or stem.util.system.is_running('tor.real')

    if not is_tor_running:
      if args.tor_path == 'tor' and not stem.util.system.is_available('tor'):
        print(format(msg('msg.tor_unavailable'), *ERROR_OUTPUT))
        sys.exit(1)
      else:
        if not args.run_cmd and not args.run_path:
          print(format(msg('msg.starting_tor'), *HEADER_OUTPUT))

        control_port = '9051' if args.control_port == 'default' else str(args.control_port)

        try:
          stem.process.launch_tor_with_config(
            config = {
              'SocksPort': '0',
              'ControlPort': control_port,
              'CookieAuthentication': '1',
              'ExitPolicy': 'reject *:*',
            },
            tor_cmd = args.tor_path,
            completion_percent = 5,
            take_ownership = True,
          )
        except OSError as exc:
          print(format(msg('msg.unable_to_start_tor', error = exc), *ERROR_OUTPUT))
          sys.exit(1)

  control_port = (args.control_address, args.control_port)
  control_socket = args.control_socket

  # If the user explicitely specified an endpoint then just try to connect to
  # that.

  if args.user_provided_socket and not args.user_provided_port:
    control_port = None
  elif args.user_provided_port and not args.user_provided_socket:
    control_socket = None

  controller = stem.connection.connect(
    control_port = control_port,
    control_socket = control_socket,
    password_prompt = True,
  )

  if controller is None:
    sys.exit(1)

  with controller:
    autocompleter = stem.interpreter.autocomplete.Autocompleter(controller)
    readline.parse_and_bind('tab: complete')
    readline.set_completer(autocompleter.complete)
    readline.set_completer_delims('\n')

    interpreter = stem.interpreter.commands.ControlInterpreter(controller)
    showed_close_confirmation = False

    if args.run_cmd:
      if args.run_cmd.upper().startswith('SETEVENTS '):
        # TODO: we can use a lambda here when dropping python 2.x support, but
        # until then print's status as a keyword prevents it from being used in
        # lambdas

        def handle_event(event_message):
          print(format(str(event_message), *STANDARD_OUTPUT))

        controller._handle_event = handle_event

        if sys.stdout.isatty():
          events = args.run_cmd.upper().split(' ', 1)[1]
          print(format('Listening to %s events. Press any key to quit.\n' % events, *HEADER_BOLD_OUTPUT))

        controller.msg(args.run_cmd)

        try:
          raw_input()
        except (KeyboardInterrupt, stem.SocketClosed):
          pass
      else:
        interpreter.run_command(args.run_cmd, print_response = True)
    elif args.run_path:
      try:
        for line in open(args.run_path).readlines():
          interpreter.run_command(line.strip(), print_response = True)
      except IOError as exc:
        print(format(msg('msg.unable_to_read_file', path = args.run_path, error = exc), *ERROR_OUTPUT))
        sys.exit(1)

    else:
      for line in msg('msg.startup_banner').splitlines():
        line_format = HEADER_BOLD_OUTPUT if line.startswith('  ') else HEADER_OUTPUT
        print(format(line, *line_format))

      print('')

      while True:
        try:
          prompt = '... ' if interpreter.is_multiline_context else PROMPT
          user_input = input(prompt) if stem.prereq.is_python_3() else raw_input(prompt)
          interpreter.run_command(user_input, print_response = True)
        except stem.SocketClosed:
          if showed_close_confirmation:
            print(format('Unable to run tor commands. The control connection has been closed.', *ERROR_OUTPUT))
          else:
            prompt = format("Tor's control port has closed. Do you want to continue this interpreter? (y/n) ", *HEADER_BOLD_OUTPUT)
            user_input = input(prompt) if stem.prereq.is_python_3() else raw_input(prompt)
            print('')  # blank line

            if user_input.lower() in ('y', 'yes'):
              showed_close_confirmation = True
            else:
              break
        except (KeyboardInterrupt, EOFError, stem.SocketClosed):
          print('')  # move cursor to the following line
          break
