"""android_autod: local control socket for wireless Android Auto projection.

Runs only when Android Auto and Bluetooth are enabled. Projection starts when the user presses
Start, or on its own when auto-connect is on and the chosen car is on (see auto_connect.py);
until then nothing but a Bluetooth status check and the car's hands-free gateway runs. Commands are one JSON line per
connection on ``ANDROID_AUTO_SOCKET_PATH``, mirroring bluetooth_managerd.

  python -m openpilot.starpilot.system.android_auto.daemon            # service
  python -m openpilot.starpilot.system.android_auto.daemon --once     # foreground diagnostic run
  python -m openpilot.starpilot.system.android_auto.daemon --once --synthetic   # test pattern, no UI needed
"""

from __future__ import annotations

import argparse
from contextlib import ExitStack
import json
import os
import signal
import socketserver
import sys
import threading
import time
from typing import Any

from openpilot.starpilot.system.android_auto.protocol import ANDROID_AUTO_SOCKET_PATH
from openpilot.starpilot.system.android_auto.source_verifier import GalaxySourceVerifier
from openpilot.starpilot.system.android_auto.supervisor import Supervisor

PAIRING_COMMANDS = {"prepare_pairing", "pairing_status", "pairing_response", "cancel_pairing", "pair_device"}
AUTHENTICATED_COMMANDS = {"start", "set_auto_connect", "select_receiver", "set_view", "set_connection",
                          "prepare_pairing", "pairing_status", "pairing_response", "cancel_pairing", "pair_device", "devices", "bluetooth_action"}


def _offroad() -> bool:
  try:
    from openpilot.common.params import Params
    return Params().get_bool("IsOffroad")
  except Exception:
    return False


def _enabled() -> bool:
  try:
    from openpilot.common.params import Params
    return Params().get_bool('AndroidAutoEnabled')
  except Exception:
    return False


def handle(supervisor: Supervisor, request: dict[str, Any], verifier: GalaxySourceVerifier | None = None, *, parked=None) -> dict[str, Any]:
  command = str(request.get("command", ""))
  if command not in {"status", "stop", "forget_receiver"}:  # forgetting a car must work with Android Auto off
    from openpilot.common.params import Params
    if not Params().get_bool("AndroidAutoEnabled"):
      raise RuntimeError("Enable Android Auto under Toggles → Android Auto first")
  if command in AUTHENTICATED_COMMANDS:
    source = request.get('source')
    if not isinstance(source, str) or verifier is None or not verifier.valid(source):
      raise RuntimeError('Authenticated Galaxy Android Auto source required')
    if command != 'bluetooth_action':
      supervisor.bind_source_session(('galaxy', source))
  if command in PAIRING_COMMANDS and not (parked or _offroad)():
    raise RuntimeError("Disengage and shift into Park before pairing")
  if command == 'bluetooth_action':
    from openpilot.starpilot.bluetooth.owner import BluetoothRejected, BluetoothUnavailable
    if set(request) != {'command', 'source', 'operation', 'address'}:
      raise ValueError('Invalid companion Bluetooth request')
    if not (parked or _offroad)():
      return {'handled': True, 'error_code': 'park_required'}
    try:
      result = supervisor.companion_bluetooth_action(request['operation'], request['address'], ('galaxy', request['source']))
    except (BluetoothRejected, BluetoothUnavailable) as error:
      return {'handled': True, 'error_code': error.code}
    except (OSError, RuntimeError):
      return {'handled': True, 'error_code': 'service_unavailable'}
    return {'handled': result is not None, **({'bluetooth': result} if result is not None else {})}
  if command == "status":
    return {"status": supervisor.status()}
  if command == "start":
    supervisor.user_start()
  elif command == "stop":
    supervisor.user_stop()
  elif command == "set_auto_connect":
    supervisor.set_auto_connect(bool(request.get("enabled", True)))
  elif command == "select_receiver":
    supervisor.select_receiver(str(request.get("address", "")), str(request.get("name", "")))
  elif command == "forget_receiver":
    return {"cleared": supervisor.forget_receiver(str(request.get("address", "")))}
  elif command == "set_view":
    supervisor.set_view(str(request.get("view", "")))
  elif command == "set_connection":
    supervisor.set_connection(str(request.get("connection", "")))
  elif command == "prepare_pairing":
    supervisor.prepare_pairing()
  elif command == "pairing_status":
    return {"pairing": supervisor.pairing_status()}
  elif command == "pair_device":
    address = request.get("address")
    if not isinstance(address, str):
      raise ValueError("Invalid Bluetooth address")
    supervisor.pair_device(address)
  elif command == "pairing_response":
    prompt, accepted = request.get('prompt_id'), request.get('accepted')
    if not isinstance(prompt, str) or type(accepted) is not bool:
      raise ValueError('Invalid pairing response')
    supervisor.pairing_response(prompt, accepted, request.get('value', ''))
  elif command == "cancel_pairing":
    supervisor.cancel_pairing()
  elif command == "devices":
    return {"devices": supervisor.devices()}
  else:
    raise RuntimeError(f"Unknown Android Auto command: {command}")
  return {}


class RequestHandler(socketserver.StreamRequestHandler):
  def handle(self) -> None:
    try:
      request = json.loads(self.rfile.readline(64 * 1024))
      response = {"ok": True, **handle(self.server.supervisor, request, self.server.source_verifier, parked=self.server.parked)}
    except Exception as error:
      response = {"ok": False, "error": str(error)}
    self.wfile.write(json.dumps(response, separators=(",", ":"), default=str).encode() + b"\n")


class Server(socketserver.ThreadingUnixStreamServer):
  daemon_threads = True

  def __init__(self, path: str, supervisor: Supervisor, source_verifier: GalaxySourceVerifier, parked=_offroad):
    self.supervisor = supervisor
    self.source_verifier = source_verifier
    self.parked = parked
    super().__init__(path, RequestHandler)


def run_once(duration: float, synthetic: bool) -> int:
  """Foreground diagnostic: start, print state changes, stop after ``duration`` seconds or Ctrl-C."""
  supervisor = Supervisor(synthetic=synthetic)
  stop = threading.Event()
  signal.signal(signal.SIGINT, lambda *_: stop.set())
  signal.signal(signal.SIGTERM, lambda *_: stop.set())
  supervisor.start()
  deadline = time.monotonic() + duration
  last = None
  try:
    while not stop.is_set() and time.monotonic() < deadline:
      status = supervisor.status()
      summary = (status["state"], status["detail"], status["error"])
      if summary != last:
        print(json.dumps({key: status[key] for key in ("state", "label", "detail", "error", "mode", "head_unit")}, default=str), flush=True)
        last = summary
      if status["state"] == "streaming" and int(time.monotonic()) % 5 == 0:
        print(json.dumps({"stats": status["stats"]}), flush=True)
      stop.wait(1.0)
  finally:
    supervisor.close()
  return 0 if supervisor.status()["error"] == "" else 1


def main() -> int:
  parser = argparse.ArgumentParser(description=__doc__, formatter_class=argparse.RawDescriptionHelpFormatter)
  parser.add_argument("--once", action="store_true", help="run one foreground session for diagnostics")
  parser.add_argument("--duration", type=float, default=900.0)
  parser.add_argument("--synthetic", action="store_true", help="with --once: send a moving test pattern instead of the UI")
  args = parser.parse_args()
  if args.once:
    return run_once(args.duration, args.synthetic)

  try:
    os.unlink(ANDROID_AUTO_SOCKET_PATH)
  except FileNotFoundError:
    pass
  from openpilot.starpilot.system.android_auto.bluetooth_bridge import SharedBluetoothOwner
  source_verifier = GalaxySourceVerifier()
  from openpilot.common.params import Params
  from openpilot.starpilot.galaxy.evidence import EvidenceSource
  from openpilot.starpilot.galaxy.settings import LiveContextSource
  with ExitStack() as cleanup:
    evidence = EvidenceSource().start()
    cleanup.callback(evidence.close)
    authority = LiveContextSource(Params(), messages=evidence, evidence_wait_ms=0)
    cleanup.callback(authority.close)
    bluetooth_owner = SharedBluetoothOwner(authority.configuration_allowed,
      session_valid=lambda session: len(session) == 2 and session[0] == 'galaxy' and source_verifier.valid(session[1]))
    cleanup.callback(bluetooth_owner.close)
    bluetooth_owner.recover_phone_role()
    supervisor = Supervisor(shared_bluetooth_owner=bluetooth_owner, projection_enabled=_enabled)
    cleanup.callback(supervisor.close)
    exit_event = threading.Event()
    cleanup.callback(exit_event.set)

    def housekeeping():
      while not exit_event.wait(2.0):
        try:
          supervisor.maintain()
        except Exception:
          pass

    threading.Thread(target=housekeeping, daemon=True).start()
    server = Server(ANDROID_AUTO_SOCKET_PATH, supervisor, source_verifier, authority.configuration_allowed)
    cleanup.callback(server.server_close)

    def shutdown(*_):
      exit_event.set()
      threading.Thread(target=server.shutdown, daemon=True).start()

    signal.signal(signal.SIGTERM, shutdown)
    signal.signal(signal.SIGINT, shutdown)
    try:
      os.chmod(ANDROID_AUTO_SOCKET_PATH, 0o660)
      server.serve_forever(poll_interval=0.5)
    finally:
      exit_event.set()
      try:
        os.unlink(ANDROID_AUTO_SOCKET_PATH)
      except FileNotFoundError:
        pass
  return 0


if __name__ == "__main__":
  sys.exit(main())