openttd-client/lib/openttd/client.py

import asyncio
import hashlib
import logging
import os
import uuid
from collections import deque
from typing import ClassVar

import monocypher
from openttd_protocol.wire.exceptions import SocketClosed
from openttd_protocol.wire.read import read_uint8, read_uint16
from openttd_protocol.wire.write import (
    SEND_TCP_MTU,
    write_init,
    write_presend,
    write_string,
    write_uint8,
    write_uint16,
    write_uint32,
)

from .decorators import exclude_call_check
from .protocol import (
    INVALID_VEH_ORDER_ID,
    GameCommand,
    ModifyTimetableCtrlFlag,
    ModifyTimetableFlags,
    NetworkAuthenticationMethod,
    OpenTTDAdminProtocol,
    OpenTTDProtocol,
    OrderStopLocation,
    OrderType,
    PacketAdminType,
    PacketGameType,
    read_varuint,
    read_varuint_signed,
    write_varuint,
    write_varuint_signed,
)


class OpenTTDClient:
    """High-level OpenTTD client for easy integration."""
    def __init__(self, host, port=3979, username="GeminiUser"):
        self.host = host
        self.port = port
        self.username = username
        self.unique_id = str(uuid.uuid4())
        self.log = logging.getLogger(f"OTTDS-{username}")
        
        # State
        self.encryption_enabled = False
        self.joined = asyncio.Event()
        self.shutdown_event = asyncio.Event()
        self.client_id = None
        self.vehicle_timetables = {}

        # Internal crypto
        self._server_password = ""
        self._company_password = ""
        self._target_company = 255 
        self._session_key_send = None
        self._session_key_recv = None
        self._encryption_nonce = None
        self._send_aead = None
        self._recv_aead = None
        
        # Callbacks
        self.on_chat = None 

    async def connect(self, server_password=""):
        """Connect to the server and initiate handshake."""
        self._server_password = server_password
        self.log.info(f"Connecting to {self.host}:{self.port}...")
        
        loop = asyncio.get_running_loop()
        try:
            self._transport, self._protocol = await loop.create_connection(
                lambda: OpenTTDProtocol(self), self.host, self.port
            )
            d = write_init(PacketGameType.ClientGameInfo)
            write_uint8(d, 4)
            await self._protocol.send_packet(write_presend(d, SEND_TCP_MTU))
        except Exception as e:
            self.log.error(f"Connection failed: {e}")
            raise

    async def join_company(self, company_id=255, company_password=""):
        """Join a specific company (0-14, or 255 for spectator)."""
        self._target_company = company_id
        self._company_password = company_password
        if not self.joined.is_set():
            self.log.info(f"Join for company {company_id} configured.")
        else:
            self.log.warning("Already joined.")

    async def _send_command(self, cmd, payload, tile=0, error_msg=0, callback=0):
        """Send a DoCommand over the game protocol (ClientCommand packet)."""
        d = write_init(PacketGameType.ClientCommand)
        write_uint8(d, self._target_company)
        write_uint16(d, cmd)
        write_uint16(d, error_msg)
        write_uint32(d, tile)
        write_uint16(d, len(payload))
        d.extend(payload)
        write_uint8(d, callback)
        if callback != 0:
            write_uint32(d, 0)
        await self._protocol.send_packet(write_presend(d, SEND_TCP_MTU))

    async def change_timetable(self, vehicle_id, order_position, flag, value, clear_field=False):
        """Change a single order's timetable field (wait/travel time, fixed flags, leave type, ...)."""
        payload = bytearray()
        write_varuint(payload, vehicle_id)
        write_uint16(payload, order_position)
        write_uint8(payload, flag)
        write_varuint(payload, value)
        write_uint8(payload, ModifyTimetableCtrlFlag.ClearField if clear_field else 0)
        await self._send_command(GameCommand.ChangeTimetable, payload)

    async def autofill_timetable(self, vehicle_id, autofill=True, preserve_wait_time=False):
        """Enable or disable timetable autofill for a vehicle."""
        payload = bytearray()
        write_varuint(payload, vehicle_id)
        write_uint8(payload, 1 if autofill else 0)
        write_uint8(payload, 1 if preserve_wait_time else 0)
        await self._send_command(GameCommand.AutofillTimetable, payload)

    async def set_timetable_start(self, vehicle_id, timetable_all, start_date):
        """Set the timetable start date for a vehicle (or all vehicles sharing its orders)."""
        payload = bytearray()
        write_varuint(payload, vehicle_id)
        write_uint8(payload, 1 if timetable_all else 0)
        write_varuint_signed(payload, start_date)
        await self._send_command(GameCommand.SetTimetableStart, payload)

    async def set_vehicle_on_time(self, vehicle_id, apply_to_group=False):
        """Reset a vehicle's lateness counter to make it on-time.

        This command can only reset lateness to zero; there is no way to mark a vehicle as
        late. If apply_to_group is True, every vehicle sharing this vehicle's order list has
        its lateness reduced by the same amount instead of just this one vehicle. The vehicle's
        timetable must already be running (see set_timetable_start()) or the server rejects
        the command when apply_to_group is False.
        """
        payload = bytearray()
        write_varuint(payload, vehicle_id)
        write_uint8(payload, 1 if apply_to_group else 0)
        await self._send_command(GameCommand.SetVehicleOnTime, payload)

    def get_vehicle_timetable(self, vehicle_id):
        """Return the locally observed timetable state for a vehicle, or None if nothing has been observed.

        This is a local read with no network round-trip: there is no query command for timetable data in
        the OpenTTD protocol, so this only reflects ServerCommand broadcasts seen since the client joined.
        """
        return self.vehicle_timetables.get(vehicle_id)

    async def add_order(self, vehicle_id, station_id, before_position=None, non_stop=0,
                        stop_location=OrderStopLocation.PlatformFarEnd, order_flags=0):
        """Insert a 'go to station' order into a vehicle's order list.

        By default the new order is appended to the end of the list; pass before_position to insert it
        before an existing order at that index instead. non_stop is an OrderNonStopFlags value
        (0 = stop everywhere) and stop_location an OrderStopLocation value, both packed into the
        order's type byte; stop_location defaults to PlatformFarEnd because the near-end/middle/through
        values are train-only and the server rejects them for other vehicle types. order_flags is the
        16-bit load/unload flag word (0 = the game's defaults: load if possible, unload if possible).

        Sent over the game port as a real DoCommand: it only succeeds when this client is joined to
        the company that owns the vehicle (see join_company()); a spectator is rejected and kicked.
        """
        order_type = OrderType.GotoStation | ((stop_location & 0x3) << 4) | ((non_stop & 0x3) << 6)
        payload = bytearray()
        write_varuint(payload, vehicle_id)
        write_uint16(payload, INVALID_VEH_ORDER_ID if before_position is None else before_position)
        write_uint8(payload, order_type)
        write_uint16(payload, order_flags)
        write_uint16(payload, station_id)
        await self._send_command(GameCommand.InsertOrder, payload)

    async def remove_order(self, vehicle_id, order_position):
        """Delete the order at order_position from a vehicle's order list.

        Sent over the game port as a real DoCommand: like add_order(), it only succeeds when this
        client is joined to the company that owns the vehicle.
        """
        payload = bytearray()
        write_varuint(payload, vehicle_id)
        write_uint16(payload, order_position)
        await self._send_command(GameCommand.DeleteOrder, payload)

    # --- Scheduled dispatch (JGRPP) ---
    #
    # A vehicle's order list can hold several dispatch schedules, each with a duration, a start
    # tick and a set of departure slots (offsets within the duration). All of these are edited over
    # the game port and require being joined to the owning company. For an authoritative read of the
    # resulting schedules, use OpenTTDAdminClient.get_dispatch().

    async def set_scheduled_dispatch(self, vehicle_id, enabled):
        """Enable or disable scheduled dispatch for a vehicle (and every vehicle sharing its orders)."""
        payload = bytearray()
        write_varuint(payload, vehicle_id)
        write_uint8(payload, 1 if enabled else 0)
        await self._send_command(GameCommand.SchDispatch, payload)

    async def add_dispatch_schedule(self, vehicle_id, start_tick, duration):
        """Create a new dispatch schedule with the given start tick and duration (in ticks).

        The schedule is appended to the vehicle's schedule set; its index is the previous schedule
        count (read it back with OpenTTDAdminClient.get_dispatch()). duration must be non-zero.
        """
        payload = bytearray()
        write_varuint(payload, vehicle_id)
        write_varuint_signed(payload, start_tick)
        write_varuint(payload, duration)
        await self._send_command(GameCommand.SchDispatchAddNewSchedule, payload)

    async def remove_dispatch_schedule(self, vehicle_id, schedule_index):
        """Remove the dispatch schedule at schedule_index from a vehicle's schedule set."""
        payload = bytearray()
        write_varuint(payload, vehicle_id)
        write_varuint(payload, schedule_index)
        await self._send_command(GameCommand.SchDispatchRemoveSchedule, payload)

    async def add_dispatch_slot(self, vehicle_id, schedule_index, offset, interval=0, extra_slots=0,
                                slot_flags=0, route_id=0):
        """Add one or more departure slots to a dispatch schedule.

        offset is the slot's departure time as an offset (in ticks) within the schedule's duration.
        To add several evenly spaced slots in one command, pass extra_slots > 0 together with a
        non-zero interval: each extra slot is placed interval ticks after the previous one (wrapping
        around the duration). slot_flags is the 16-bit slot flag word and route_id an optional
        departure route id (both default to 0).
        """
        payload = bytearray()
        write_varuint(payload, vehicle_id)
        write_varuint(payload, schedule_index)
        write_varuint(payload, offset)
        write_varuint(payload, interval)
        write_varuint(payload, extra_slots)
        write_uint16(payload, slot_flags)
        write_uint8(payload, route_id)
        await self._send_command(GameCommand.SchDispatchAdd, payload)

    async def remove_dispatch_slot(self, vehicle_id, schedule_index, offset):
        """Remove the departure slot at the given offset from a dispatch schedule."""
        payload = bytearray()
        write_varuint(payload, vehicle_id)
        write_varuint(payload, schedule_index)
        write_varuint(payload, offset)
        await self._send_command(GameCommand.SchDispatchRemove, payload)

    async def clear_dispatch_schedule(self, vehicle_id, schedule_index):
        """Remove every departure slot from a dispatch schedule (leaving the schedule itself)."""
        payload = bytearray()
        write_varuint(payload, vehicle_id)
        write_varuint(payload, schedule_index)
        await self._send_command(GameCommand.SchDispatchClear, payload)

    async def set_dispatch_duration(self, vehicle_id, schedule_index, duration):
        """Set the total duration (in ticks) of a dispatch schedule."""
        payload = bytearray()
        write_varuint(payload, vehicle_id)
        write_varuint(payload, schedule_index)
        write_varuint(payload, duration)
        await self._send_command(GameCommand.SchDispatchSetDuration, payload)

    async def set_dispatch_start_date(self, vehicle_id, schedule_index, start_tick):
        """Set the start tick of a dispatch schedule."""
        payload = bytearray()
        write_varuint(payload, vehicle_id)
        write_varuint(payload, schedule_index)
        write_varuint_signed(payload, start_tick)
        await self._send_command(GameCommand.SchDispatchSetStartDate, payload)

    def disconnect(self, source):
        """Library callback for when connection is lost."""
        self.log.info("Disconnected.")
        self.shutdown_event.set()

    async def quit(self):
        """Gracefully disconnect from the server."""
        if hasattr(self, '_protocol') and not self._transport.is_closing():
            self.log.info("Quitting...")
            try:
                d = write_init(PacketGameType.ClientQuit)
                await self._protocol.send_packet(write_presend(d, SEND_TCP_MTU))
            except (OSError, SocketClosed) as e:
                # Best-effort courtesy packet: the socket may already be gone.
                self.log.debug(f"Could not send quit packet: {e}")
            self._transport.close()
        self.shutdown_event.set()

    # --- Internal Protocol Callbacks ---

    @exclude_call_check
    def connected(self, source): pass

    async def receive_ServerGameInfo(self, source, **kwargs):
        self.log.info(f"Server Info: {kwargs.get('name')} ({kwargs.get('openttd_version')})")
        d = write_init(PacketGameType.ClientJoin)
        write_string(d, kwargs.get("openttd_version", "jgrpp-0.71.1"))
        write_uint32(d, 0x20006D64) 
        await self._protocol.send_packet(write_presend(d, SEND_TCP_MTU))

    async def receive_ServerError(self, source, error_code):
        error_names = {
            0: "General",
            1: "Desync",
            2: "SavegameFailed",
            3: "ConnectionLost",
            4: "IllegalPacket",
            5: "NewGRFMismatch",
            6: "NotAuthorized",
            7: "NotExpected",
            8: "WrongRevision",
            9: "NameInUse",
            10: "WrongPassword",
            11: "CompanyMismatch",
            12: "Kicked",
            13: "Cheater",
            14: "ServerFull",
            15: "TooManyCommands",
            16: "TimeoutPassword",
            17: "TimeoutComputer",
            18: "TimeoutMap",
            19: "TimeoutJoin",
            20: "InvalidClientName",
            21: "NotOnAllowList",
            22: "NoAuthenticationMethodAvailable"
        }
        self.log.error(f"Server Error: {error_names.get(error_code, f'Code {error_code}')}")
        await self.quit()

    async def receive_ServerAuthenticationRequest(self, source, auth_type, data):
        if auth_type == 1:
            server_pub = bytes(data[:32])
            nonce = bytes(data[32:56])
            our_priv = monocypher.generate_key()
            our_pub = monocypher.x25519_public_key(our_priv)
            shared_secret = monocypher.x25519(our_priv, server_pub)
            derived = monocypher.blake2b(shared_secret + server_pub + our_pub + self._server_password.encode())
            self._session_key_send, self._session_key_recv = derived[:32], derived[32:64]
            challenge = os.urandom(8)
            mac, ciphertext = monocypher.lock(self._session_key_send, nonce, challenge, associated_data=our_pub)
            d = write_init(PacketGameType.ClientAuthenticationResponse)
            d.extend(our_pub + mac + ciphertext)
            await self._protocol.send_packet(write_presend(d, SEND_TCP_MTU))

    async def receive_ServerEnableEncryption(self, source, data):
        self._encryption_nonce = bytes(data)
        self.encryption_enabled = True
        d = write_init(PacketGameType.ClientIdentify)
        write_string(d, self.username)
        write_uint8(d, self._target_company)
        write_uint8(d, 1) 
        write_string(d, self.unique_id)
        await self._protocol.send_packet(write_presend(d, SEND_TCP_MTU))

    async def receive_ServerCheckNewGRFs(self, source):
        d = write_init(PacketGameType.ClientNewGRFsChecked)
        await self._protocol.send_packet(write_presend(d, SEND_TCP_MTU))

    async def receive_ServerNeedCompanyPassword(self, source, seed, server_id):
        if not self._company_password:
            self.log.error("Server needs company password but none provided.")
            return
        salted = bytearray()
        p_bytes, s_bytes = self._company_password.encode('utf-8'), server_id.encode('utf-8')
        for i in range(32):
            p_char = p_bytes[i] if i < len(p_bytes) else 0
            s_char = s_bytes[i] if i < len(s_bytes) else 0
            seed_char = (seed >> (i % 32)) & 0xFF
            salted.append(p_char ^ s_char ^ seed_char)
        hashed = hashlib.md5(salted, usedforsecurity=False).hexdigest()
        d = write_init(PacketGameType.ClientCompanyPassword)
        write_string(d, hashed)
        await self._protocol.send_packet(write_presend(d, SEND_TCP_MTU))

    async def receive_ServerWelcome(self, source, **kwargs):
        self.client_id = kwargs.get('client_id')
        self.log.info(f"Successfully joined as client {self.client_id}")
        d = write_init(PacketGameType.ClientGetMap)
        write_uint8(d, 0)
        await self._protocol.send_packet(write_presend(d, SEND_TCP_MTU))

    async def receive_ServerMapDone(self, source):
        d = write_init(PacketGameType.ClientMapOk)
        await self._protocol.send_packet(write_presend(d, SEND_TCP_MTU))
        self.joined.set()

    async def receive_ServerFrame(self, source, frame, token):
        d = write_init(PacketGameType.ClientAck)
        write_uint32(d, frame)
        write_uint8(d, token)
        await self._protocol.send_packet(write_presend(d, SEND_TCP_MTU))

    async def receive_ServerChat(self, source, client_id, message, **kwargs):
        if self.on_chat:
            self.on_chat(client_id, message)
        else:
            self.log.info(f"CHAT: <{client_id}> {message}")

    async def receive_ServerUnused(self, source, **kwargs): pass
    async def receive_ServerCompanyUpdate(self, source, **kwargs): pass
    async def receive_ServerClientInfo(self, source, **kwargs): pass
    async def receive_ServerSync(self, source, **kwargs): pass
    async def receive_ServerClientJoined(self, source, **kwargs): pass
    async def receive_ServerMapBegin(self, source, **kwargs): pass
    async def receive_ServerMapSize(self, source, **kwargs): pass
    async def receive_ServerMapData(self, source, **kwargs): pass
    async def receive_ServerConfigurationUpdate(self, source, **kwargs): pass
    async def receive_ServerExternalChat(self, source, **kwargs): pass
    _TIMETABLE_FIELD_BY_FLAG: ClassVar[dict[ModifyTimetableFlags, str]] = {
        ModifyTimetableFlags.WaitTime: "wait_time",
        ModifyTimetableFlags.TravelTime: "travel_time",
        ModifyTimetableFlags.TravelSpeed: "travel_speed",
        ModifyTimetableFlags.SetWaitFixed: "wait_time_fixed",
        ModifyTimetableFlags.SetTravelFixed: "travel_time_fixed",
        ModifyTimetableFlags.SetLeaveType: "leave_type",
        ModifyTimetableFlags.AssignSchedule: "assigned_schedule",
    }
    _TIMETABLE_BOOL_FLAGS: ClassVar[set[ModifyTimetableFlags]] = {
        ModifyTimetableFlags.SetWaitFixed,
        ModifyTimetableFlags.SetTravelFixed,
    }

    async def receive_ServerCommand(self, source, cmd, payload, **kwargs):
        if cmd == GameCommand.ChangeTimetable:
            vehicle_id, rest = read_varuint(payload)
            order_position, rest = read_uint16(rest)
            flag, rest = read_uint8(rest)
            value, rest = read_varuint(rest)
            ctrl_flags, _ = read_uint8(rest)
            entry = self.vehicle_timetables.setdefault(vehicle_id, {"orders": {}})
            order = entry["orders"].setdefault(order_position, {})
            field = self._TIMETABLE_FIELD_BY_FLAG.get(flag)
            if field:
                cleared = bool(ctrl_flags & ModifyTimetableCtrlFlag.ClearField)
                if cleared:
                    order[field] = None
                elif flag in self._TIMETABLE_BOOL_FLAGS:
                    order[field] = bool(value)
                else:
                    order[field] = value
        elif cmd == GameCommand.AutofillTimetable:
            vehicle_id, rest = read_varuint(payload)
            autofill, rest = read_uint8(rest)
            preserve_wait_time, _ = read_uint8(rest)
            entry = self.vehicle_timetables.setdefault(vehicle_id, {"orders": {}})
            entry["autofill"] = bool(autofill)
            entry["autofill_preserve_wait_time"] = bool(preserve_wait_time)
        elif cmd == GameCommand.SetTimetableStart:
            vehicle_id, rest = read_varuint(payload)
            timetable_all, rest = read_uint8(rest)
            start_date, _ = read_varuint_signed(rest)
            entry = self.vehicle_timetables.setdefault(vehicle_id, {"orders": {}})
            entry["timetable_all"] = bool(timetable_all)
            entry["timetable_start"] = start_date
        elif cmd == GameCommand.SetVehicleOnTime:
            vehicle_id, rest = read_varuint(payload)
            apply_to_group, _ = read_uint8(rest)
            entry = self.vehicle_timetables.setdefault(vehicle_id, {"orders": {}})
            entry["on_time_apply_to_group"] = bool(apply_to_group)

    async def receive_ServerFull(self, source, **kwargs): pass
    async def receive_ServerBanned(self, source, **kwargs): pass
    async def receive_ClientAck(self, source, **kwargs): pass
    async def receive_ClientIdentify(self, source, **kwargs): pass

class OpenTTDAdminClient:
    """High-level OpenTTD Admin client."""
    def __init__(self, host, port=3977, admin_name="GeminiAdmin", event_buffer_size=256):
        self.host = host
        self.port = port
        self.admin_name = admin_name
        self.log = logging.getLogger(f"OTTDA-{admin_name}")

        # State
        self.encryption_enabled = False
        self.joined = asyncio.Event()
        self.shutdown_event = asyncio.Event()

        # Internal crypto
        self._admin_password = ""
        self._session_key_send = None
        self._session_key_recv = None
        self._encryption_nonce = None
        self._send_aead = None
        self._recv_aead = None

        # Callbacks
        self.on_chat = None
        self.on_console = None
        self.on_gamescript = None
        self.on_event = None

        # GameScript request/response correlation
        self._gs_request_id = 0
        self._gs_futures = {}
        self._gs_subscribed = False

        # Game events pushed by the AdminBridge GameScript. Events nobody is waiting for are
        # kept here so a wait_for_event() call can still pick up something that arrived just
        # before it; the deque bounds the memory a subscription nobody drains can cost.
        self._event_buffer = deque(maxlen=event_buffer_size)
        self._event_waiters = []

    async def connect(self, admin_password="", secure=False):
        """Connect to the admin port and initiate handshake."""
        self._admin_password = admin_password
        self.log.info(f"Connecting to admin {self.host}:{self.port}...")
        
        loop = asyncio.get_running_loop()
        try:
            self._transport, self._protocol = await loop.create_connection(
                lambda: OpenTTDAdminProtocol(self), self.host, self.port
            )
            if secure:
                d = write_init(PacketAdminType.AdminJoinSecure)
                write_string(d, self.admin_name)
                write_string(d, "1.0")
                # Bitmask: 1 << NetworkAuthenticationMethod.X25519_PAKE
                write_uint16(d, 1 << NetworkAuthenticationMethod.X25519_PAKE)
            else:
                d = write_init(PacketAdminType.AdminJoin)
                write_string(d, self._admin_password)
                write_string(d, self.admin_name)
                write_string(d, "1.0")
            await self._protocol.send_packet(write_presend(d, SEND_TCP_MTU))
        except Exception as e:
            self.log.error(f"Admin connection failed: {e}")
            raise

    def disconnect(self, source):
        """Library callback for when connection is lost."""
        self.log.info("Admin disconnected.")
        for fut in self._gs_futures.values():
            if not fut.done():
                fut.set_exception(ConnectionError("admin disconnected"))
        self._gs_futures.clear()
        for _, fut in self._event_waiters:
            if not fut.done():
                fut.set_exception(ConnectionError("admin disconnected"))
        self._event_waiters.clear()
        self.shutdown_event.set()

    async def quit(self):
        """Gracefully disconnect from the server."""
        if hasattr(self, '_protocol') and not self._transport.is_closing():
            try:
                d = write_init(PacketAdminType.AdminQuit)
                await self._protocol.send_packet(write_presend(d, SEND_TCP_MTU))
            except (OSError, SocketClosed) as e:
                # Best-effort courtesy packet: the socket may already be gone.
                self.log.debug(f"Could not send admin quit packet: {e}")
            self._transport.close()
        self.shutdown_event.set()

    async def send_rcon(self, command):
        """Send an RCON command."""
        d = write_init(PacketAdminType.AdminRcon)
        write_string(d, command)
        await self._protocol.send_packet(write_presend(d, SEND_TCP_MTU))

    async def send_chat(self, message, action=1, dest_type=0, dest_id=0):
        """Send a chat message as admin. action=1 (CHAT), dest_type=0 (BROADCAST)."""
        d = write_init(PacketAdminType.AdminChat)
        write_uint8(d, action)
        write_uint8(d, dest_type)
        write_uint32(d, dest_id)
        write_string(d, message)
        await self._protocol.send_packet(write_presend(d, SEND_TCP_MTU))

    async def update_frequency(self, update_type, frequency):
        """Update the frequency of a certain piece of information."""
        d = write_init(PacketAdminType.AdminUpdateFrequency)
        write_uint16(d, update_type)
        write_uint16(d, frequency)
        await self._protocol.send_packet(write_presend(d, SEND_TCP_MTU))

    async def poll(self, update_type, data=0xFFFFFFFF):
        """Poll the server for certain updates."""
        d = write_init(PacketAdminType.AdminPoll)
        write_uint8(d, update_type)
        write_uint32(d, data)
        await self._protocol.send_packet(write_presend(d, SEND_TCP_MTU))

    async def poll_clients(self, client_id=0xFFFFFFFF):
        """Poll for client information."""
        from .protocol import AdminUpdateType
        await self.poll(AdminUpdateType.ClientInfo, client_id)

    async def poll_companies(self, company_id=0xFFFFFFFF):
        """Poll for company information."""
        from .protocol import AdminUpdateType
        await self.poll(AdminUpdateType.CompanyInfo, company_id)

    async def poll_economy(self, company_id=0xFFFFFFFF):
        """Poll for company economy information."""
        from .protocol import AdminUpdateType
        await self.poll(AdminUpdateType.CompanyEconomy, company_id)

    async def poll_stats(self, company_id=0xFFFFFFFF):
        """Poll for company statistics."""
        from .protocol import AdminUpdateType
        await self.poll(AdminUpdateType.CompanyStats, company_id)

    async def list_vehicles(self, company_id=None):
        """Request a list of vehicles via GameScript. company_id=None for all companies."""
        payload = {"command": "list_vehicles"}
        if company_id is not None:
            payload["company_id"] = company_id
        await self.send_gamescript(payload)

    async def list_stations(self, company_id=None):
        """Request a list of stations via GameScript. company_id=None for all companies.

        Like list_vehicles(), this is fire-and-forget: the AdminBridge GameScript replies with a
        {"stations": [...]} envelope delivered to the on_gamescript callback, so subscribe to
        Gamescript updates first (update_frequency(Gamescript, Automatic)) or the reply is dropped.
        For a station's live cargo detail (waiting vs planned), use get_station().
        """
        payload = {"command": "list_stations"}
        if company_id is not None:
            payload["company_id"] = company_id
        await self.send_gamescript(payload)

    async def _gs_query(self, payload, timeout, context):
        """Send a GameScript request and await its correlated reply.

        Assigns a fresh request_id, registers a future the ServerGamescript handler resolves when
        the matching reply arrives, and (on first use) subscribes to Gamescript updates so the
        server actually forwards the reply. `payload` is the request dict without request_id;
        `context` is a label used in the ValueError raised on a GameScript-reported error.

        Raises asyncio.TimeoutError if no reply arrives within `timeout`, ValueError on an error
        reply, and ConnectionError if the admin connection drops while waiting.
        """
        from .protocol import AdminUpdateFrequency, AdminUpdateType
        if not self._gs_subscribed:
            await self.update_frequency(AdminUpdateType.Gamescript, AdminUpdateFrequency.Automatic)
            self._gs_subscribed = True
        self._gs_request_id += 1
        rid = self._gs_request_id
        fut = asyncio.get_running_loop().create_future()
        self._gs_futures[rid] = fut
        request = dict(payload)
        request["request_id"] = rid
        try:
            await self.send_gamescript(request)
            data = await asyncio.wait_for(fut, timeout)
        finally:
            self._gs_futures.pop(rid, None)
        if "error" in data:
            raise ValueError(f"{context}: {data['error']}")
        return data

    async def get_bridge_version(self, minimum=None, timeout=5.0):
        """Ask the AdminBridge GameScript which protocol version it speaks, and check it is new enough.

        Every other GameScript method here needs a bridge that understands the command it sends.
        Against an older bridge those commands are simply ignored and the caller waits out its
        timeout with no explanation, so call this once after connecting to turn that into an
        immediate, named failure.

        Returns a dict with "version" (the bridge's protocol version), "commands" (the command
        names it answers) and "events" (the event kinds it can push) — the two catalogues allow
        feature-detecting a single command instead of comparing version numbers.

        `minimum` defaults to GS_BRIDGE_VERSION, the version this client is written against;
        pass 0 to read the version without requiring anything of it.

        Raises ValueError if the bridge is older than `minimum`, and asyncio.TimeoutError if it
        does not answer at all — note that a bridge predating get_version itself (version 3 and
        earlier) can only fail that second way, as can a paused game or a server with no bridge
        loaded. ConnectionError if the admin connection drops while waiting.
        """
        from .protocol import GS_BRIDGE_VERSION
        if minimum is None:
            minimum = GS_BRIDGE_VERSION
        data = await self._gs_query({"command": "get_version"}, timeout, "get_version")
        version = data.get("version", 0)
        if version < minimum:
            raise ValueError(
                f"AdminBridge GameScript is version {version}, but at least {minimum} is "
                f"required; update the server's copy from gamescript/AdminBridge/")
        return data

    async def get_timetable(self, vehicle_id, timeout=5.0):
        """Fetch an authoritative timetable snapshot for a vehicle via the AdminBridge GameScript.

        Unlike the game client's passive observer, this queries the real game state: it works for
        timetables set before this client connected and reflects the actual (not requested) values.
        Auto-subscribes to Gamescript updates on first use; if you manage update frequencies
        yourself, ensure update_frequency(Gamescript, Automatic) is active before calling.

        Returns a dict with vehicle-level keys (lateness, start_tick, current_order_time,
        total_duration) and an "orders" list of per-order dicts (position, wait_time, travel_time,
        wait_timetabled, travel_timetabled, wait_fixed, travel_fixed, leave_type, max_speed).

        Raises asyncio.TimeoutError if no reply arrives (e.g. game paused, GS not loaded),
        ValueError on a GameScript-reported error (invalid_vehicle, response_too_large), and
        ConnectionError if the admin connection drops while waiting.
        """
        return await self._gs_query(
            {"command": "get_timetable", "vehicle_id": vehicle_id}, timeout,
            f"get_timetable({vehicle_id})")

    async def get_station(self, station_id, timeout=5.0):
        """Fetch an authoritative snapshot of a station's live cargo state via the AdminBridge GameScript.

        This queries the real game state (like get_timetable() does for vehicles): it works for any
        existing station regardless of when it was built or when this client connected. Auto-subscribes
        to Gamescript updates on first use; if you manage update frequencies yourself, ensure
        update_frequency(Gamescript, Automatic) is active before calling.

        Returns a dict with station-level keys (name, location, owner) and a "cargo" list of per-cargo
        dicts. Each cargo dict carries both the real-time and the planned amounts:
          - "waiting": units currently sitting at the station (real-time, GSStation.GetCargoWaiting)
          - "planned": units planned to move through it per the cargodist link graph
            (GSStation.GetCargoPlanned); 0 when cargo distribution is not enabled for that cargo
          - "rating": the station's acceptance rating for the cargo as a percentage (0-100),
            or None if the station has no rating for that cargo yet
        Only cargo types the station has ever handled appear in the list.

        Raises asyncio.TimeoutError if no reply arrives (e.g. game paused, GS not loaded),
        ValueError on a GameScript-reported error (invalid_station, response_too_large), and
        ConnectionError if the admin connection drops while waiting.
        """
        return await self._gs_query(
            {"command": "get_station", "station_id": station_id}, timeout,
            f"get_station({station_id})")

    async def get_station_cargo(self, station_id, cargo_id, from_station=None, via_station=None, timeout=5.0):
        """Fetch a per-source / per-next-hop breakdown of one cargo at a station via the AdminBridge GS.

        Where get_station() reports each cargo's totals, this drills into a single cargo type and
        shows how the waiting (real-time) and planned amounts split across the cargo distribution
        (cargodist) link graph. Cargodist tracks every unit by its source station (where it was
        first loaded) and its next hop (the next station it heads to on the way to its final
        destination); there is no separate "final destination" store, so the routing destination is
        the next hop ("via").

        Returns a dict with the (optionally filtered) totals "waiting" and "planned", plus four
        breakdown lists, each a list of {"station": id, "amount": n} entries (zero amounts omitted):
          - "waiting_by_from" / "planned_by_from": grouped by source station
          - "waiting_by_via"  / "planned_by_via":  grouped by next hop (routing destination)
        A station id of 65535 (STATION_INVALID) marks cargo whose source was deleted or, as a next
        hop, cargo with no onward routing / to be consumed at this station (also the sole next hop
        for cargo types using manual, non-cargodist distribution).

        Optional filters narrow the query:
          - from_station: only cargo originating at this source station.
          - via_station: only cargo whose next hop is this station.
        Passing from_station restricts the by_via breakdown to that source (and the totals to it);
        passing via_station restricts the by_from breakdown to that next hop; passing both makes the
        totals the exact source+next-hop amount. Pass 65535 for either to target STATION_INVALID.

        Raises asyncio.TimeoutError if no reply arrives (e.g. game paused, GS not loaded),
        ValueError on a GameScript-reported error (invalid_station, invalid_cargo,
        response_too_large), and ConnectionError if the admin connection drops while waiting.
        """
        payload = {"command": "get_station_cargo", "station_id": station_id, "cargo_id": cargo_id}
        if from_station is not None:
            payload["from_station"] = from_station
        if via_station is not None:
            payload["via_station"] = via_station
        return await self._gs_query(payload, timeout, f"get_station_cargo({station_id}, {cargo_id})")

    async def list_cargo(self, timeout=5.0):
        """Fetch the running game's cargo table via the AdminBridge GameScript, id to label.

        Every other reply names a cargo by its bare numeric id — get_station()'s and
        get_station_cargo()'s cargo_id, the cargo_waiting events, the per-cargo load on vehicle
        events. Those ids index the cargo table the loaded NewGRFs build, so they mean different
        things in different games and are not worth hardcoding; resolve them against this list
        instead. Auto-subscribes to Gamescript updates on first use; if you manage update
        frequencies yourself, ensure update_frequency(Gamescript, Automatic) is active before
        calling.

        Returns a dict with a "cargo" list holding every cargo type in the game, in no particular
        order (index it by "cargo_id"; a cargo's position in the list is not its id). Each entry:
          - "cargo_id": the id used by all the replies above
          - "label": the cargo label ("PASS", "COAL", ...), or "" if the GameScript could not
            read it
          - "freight": 1 for freight cargo, 0 for the rest (passengers, mail, ...)

        Raises asyncio.TimeoutError if no reply arrives (e.g. game paused, GS not loaded) and
        ConnectionError if the admin connection drops while waiting. The GameScript reports no
        error for this command, so unlike get_station() it never raises ValueError.
        """
        return await self._gs_query({"command": "list_cargo"}, timeout, "list_cargo")

    async def get_dispatch(self, vehicle_id, timeout=5.0):
        """Fetch an authoritative snapshot of a vehicle's scheduled dispatch state via the AdminBridge GS.

        Scheduled dispatch (a JGRPP feature) lets a vehicle depart on a fixed schedule of slots rather
        than purely by timetable. This reads the live state (like get_timetable() does), so it works for
        schedules created before this client connected and reflects the real values. Auto-subscribes to
        Gamescript updates on first use; if you manage update frequencies yourself, ensure
        update_frequency(Gamescript, Automatic) is active before calling.

        Returns a dict with:
          - "enabled": 1 if scheduled dispatch is turned on for the vehicle, else 0
          - "schedules": a list of per-schedule dicts, each with "index", "duration" (ticks),
            "start_tick", "delay" (max allowed delay), "reuse_slots" (0/1), and "slots" — a list of
            {"offset", "flags"} departure slots (offset is ticks within the schedule duration).

        These are the same schedules and slots edited by the game-port methods on OpenTTDClient
        (add_dispatch_schedule/add_dispatch_slot/...). Raises asyncio.TimeoutError if no reply arrives
        (e.g. game paused, GS not loaded), ValueError on a GameScript-reported error (invalid_vehicle,
        response_too_large), and ConnectionError if the admin connection drops while waiting.
        """
        return await self._gs_query(
            {"command": "get_dispatch", "vehicle_id": vehicle_id}, timeout,
            f"get_dispatch({vehicle_id})")

    # --- Game events ---
    #
    # Everything above is a request the caller makes; this is the other direction. The
    # AdminBridge GameScript pushes events as they happen, so a bot can react to the game
    # instead of polling it. Two kinds of thing arrive on the same channel: transitions the
    # bridge synthesises by sampling game state on an interval (a vehicle reaching or leaving
    # a stop, a station's waiting cargo changing), and the events the engine itself raises for
    # a GameScript (crashes, industries opening, companies going bankrupt, ...). See
    # GameEventType for the full catalogue.
    #
    # Consume them either by setting on_event (push) or by awaiting wait_for_event() (pull);
    # both see every event, so the two can be mixed.

    async def subscribe_events(self, events=None, interval=None, company_id=None, vehicles=None,
                               stations=None, cargo=None, min_cargo_delta=None,
                               include_cargo=None, timeout=5.0):
        """Ask the AdminBridge GameScript to start pushing game events, and wait for it to confirm.

        Every argument narrows what gets sent; the defaults subscribe to every event kind for
        every vehicle, station and cargo, which is the right starting point on a small map and
        the wrong one on a large busy map (see the cost note below).

          - events: which GameEventType kinds to receive (default: all of them).
          - interval: ticks between state samples for the polled kinds (default 10). This is
            the resolution of those events, not a delay: a stop shorter than `interval` can
            begin and end between two samples and is then never reported at all.
          - company_id: only report vehicles and stations owned by this company.
          - vehicles / stations: only sample these ids, instead of every vehicle / station.
          - cargo: only inspect these cargo types (for cargo_waiting and for the load reported
            on vehicle events).
          - min_cargo_delta: suppress cargo_waiting events whose amount moved by less than this
            many units since the previous sample (default 1, i.e. report every change).
          - include_cargo: set False to leave the per-cargo load off vehicle events.

        Subscribing replaces any previous subscription and resets the bridge's baseline, so the
        first sample after this call only records where everything already is — a vehicle that
        was sitting at a station when you subscribed did not just arrive, and gets no event.

        Cost: the bridge samples every watched vehicle and every watched station-cargo pair on
        each interval, inside a GameScript's limited per-tick budget. On a large map prefer a
        coarser interval and explicit vehicles/stations/cargo lists over the defaults.

        Returns the confirmation dict: {"events": [accepted kinds], "interval": N}. Raises
        asyncio.TimeoutError if the GameScript does not answer (e.g. game paused, GS not
        loaded), ValueError on a rejected request (unknown_event, invalid_interval,
        invalid_min_cargo_delta, invalid_cargo), and ConnectionError if the admin connection
        drops while waiting.
        """
        payload = {"command": "subscribe_events"}
        if events is not None:
            payload["events"] = [str(event) for event in events]
        if interval is not None:
            payload["interval"] = interval
        if company_id is not None:
            payload["company_id"] = company_id
        if vehicles is not None:
            payload["vehicles"] = list(vehicles)
        if stations is not None:
            payload["stations"] = list(stations)
        if cargo is not None:
            payload["cargo"] = list(cargo)
        if min_cargo_delta is not None:
            payload["min_cargo_delta"] = min_cargo_delta
        if include_cargo is not None:
            payload["include_cargo"] = bool(include_cargo)
        return await self._gs_query(payload, timeout, "subscribe_events")

    async def unsubscribe_events(self, timeout=5.0):
        """Stop the event stream and wait for the GameScript to confirm.

        This also drops the bridge's sampling state, so a later subscribe_events() starts from
        a fresh baseline. Events already delivered stay in this client's buffer; drain or ignore
        them as you like.
        """
        return await self._gs_query({"command": "unsubscribe_events"}, timeout,
                                    "unsubscribe_events")

    async def wait_for_event(self, kind=None, timeout=5.0):
        """Await the next game event, optionally of a specific kind (or any of several kinds).

        `kind` is a GameEventType (or plain string), an iterable of them, or None for "any
        event". Events that arrived earlier and were not taken by another waiter are buffered,
        so this returns immediately when a matching one is already in hand; the oldest matching
        event wins. An event is handed to at most one waiter, but the on_event callback (if set)
        still sees every event regardless.

        Returns the event dict, which always carries "event" (its GameEventType) and "tick"
        (the game tick it was observed at) plus per-kind fields — see docs/EVENTS.md. Raises
        asyncio.TimeoutError if nothing matching arrives in time (note that a subscription is
        needed first — see subscribe_events()) and ConnectionError if the admin connection drops
        while waiting.
        """
        kinds = None
        if kind is not None:
            kinds = {str(kind)} if isinstance(kind, str) else {str(k) for k in kind}
        for buffered in list(self._event_buffer):
            if self._event_matches(buffered, kinds):
                self._event_buffer.remove(buffered)
                return buffered
        fut = asyncio.get_running_loop().create_future()
        waiter = (kinds, fut)
        self._event_waiters.append(waiter)
        try:
            return await asyncio.wait_for(fut, timeout)
        finally:
            if waiter in self._event_waiters:
                self._event_waiters.remove(waiter)

    @staticmethod
    def _event_matches(event, kinds):
        return kinds is None or (isinstance(event, dict) and event.get("event") in kinds)

    def _dispatch_event(self, event):
        """Hand one event to the longest-waiting matching waiter, else buffer it; then observe."""
        for waiter in self._event_waiters:
            kinds, fut = waiter
            if not fut.done() and self._event_matches(event, kinds):
                fut.set_result(event)
                self._event_waiters.remove(waiter)
                break
        else:
            self._event_buffer.append(event)
        if self.on_event:
            self.on_event(event)

    async def send_gamescript(self, json_data):
        """Send a JSON string to the GameScript."""
        import json
        d = write_init(PacketAdminType.AdminGamescript)
        write_string(d, json.dumps(json_data))
        await self._protocol.send_packet(write_presend(d, SEND_TCP_MTU))

    # --- Internal Protocol Callbacks ---

    @exclude_call_check
    def connected(self, source): pass

    async def receive_ServerAuthRequest(self, source, auth_type, data):
        if auth_type == 1: # X25519_PAKE
            server_pub = bytes(data[:32])
            nonce = bytes(data[32:56])
            our_priv = monocypher.generate_key()
            our_pub = monocypher.x25519_public_key(our_priv)
            shared_secret = monocypher.x25519(our_priv, server_pub)
            derived = monocypher.blake2b(shared_secret + server_pub + our_pub + self._admin_password.encode())
            self._session_key_send, self._session_key_recv = derived[:32], derived[32:64]
            challenge = os.urandom(8)
            mac, ciphertext = monocypher.lock(self._session_key_send, nonce, challenge, associated_data=our_pub)
            d = write_init(PacketAdminType.AdminAuthResponse)
            d.extend(our_pub + mac + ciphertext)
            await self._protocol.send_packet(write_presend(d, SEND_TCP_MTU))

    async def receive_ServerEnableEncryption(self, source, data):
        self._encryption_nonce = bytes(data)
        self.encryption_enabled = True
        self.log.info("Admin encryption enabled.")

    async def receive_ServerProtocol(self, source, version, updates):
        self.log.info(f"Admin Protocol version {version}")

    async def receive_ServerWelcome(self, source, **kwargs):
        self.log.info(f"Admin welcomed to {kwargs.get('server_name')}")
        self.joined.set()

    async def receive_ServerError(self, source, error_code):
        self.log.error(f"Admin Server Error: {error_code}")
        await self.quit()

    async def receive_ServerChat(self, source, **kwargs):
        if self.on_chat:
            self.on_chat(**kwargs)
        else:
            self.log.info(f"ADMIN CHAT: <{kwargs.get('client_id')}> {kwargs.get('message')}")

    async def receive_ServerConsole(self, source, **kwargs):
        if self.on_console:
            self.on_console(**kwargs)
        else:
            self.log.info(f"CONSOLE: [{kwargs.get('origin')}] {kwargs.get('text')}")

    async def receive_ServerRcon(self, source, **kwargs):
        self.log.info(f"RCON: {kwargs.get('text')}")

    async def receive_ServerRconEnd(self, source, **kwargs):
        self.log.info(f"RCON End: {kwargs.get('command')}")

    async def receive_ServerClientJoin(self, source, **kwargs):
        self.log.info(f"Admin: Client {kwargs.get('client_id')} joined.")

    async def receive_ServerClientInfo(self, source, **kwargs):
        self.log.info(f"Admin: Client Info: {kwargs.get('name')} (ID: {kwargs.get('client_id')}, IP: {kwargs.get('network_address')})")

    async def receive_ServerClientUpdate(self, source, **kwargs):
        self.log.info(f"Admin: Client {kwargs.get('client_id')} updated.")

    async def receive_ServerClientQuit(self, source, **kwargs):
        self.log.info(f"Admin: Client {kwargs.get('client_id')} quit.")

    async def receive_ServerClientError(self, source, **kwargs):
        self.log.info(f"Admin: Client {kwargs.get('client_id')} error: {kwargs.get('error_code')}")

    async def receive_ServerCompanyNew(self, source, **kwargs):
        self.log.info(f"Admin: Company {kwargs.get('company_id')} created.")

    async def receive_ServerCompanyInfo(self, source, **kwargs):
        self.log.info(f"Admin: Company Info: {kwargs.get('name')} (ID: {kwargs.get('company_id')})")

    async def receive_ServerCompanyUpdate(self, source, **kwargs):
        self.log.info(f"Admin: Company {kwargs.get('company_id')} updated.")

    async def receive_ServerCompanyRemove(self, source, **kwargs):
        self.log.info(f"Admin: Company {kwargs.get('company_id')} removed.")

    async def receive_ServerCompanyEconomy(self, source, **kwargs):
        self.log.info(f"Admin: Company {kwargs.get('company_id')} Economy: Money={kwargs.get('money')}, Loan={kwargs.get('loan')}")

    async def receive_ServerCompanyStats(self, source, **kwargs):
        self.log.info(f"Admin: Company {kwargs.get('company_id')} Stats: Vehicles={kwargs.get('vehicles')}, Stations={kwargs.get('stations')}")

    async def receive_ServerGamescript(self, source, **kwargs):
        data = kwargs.get('data')
        if isinstance(data, dict):
            fut = self._gs_futures.get(data.get('request_id'))
            if fut is not None:
                if not fut.done():
                    fut.set_result(data)
                return
            # Unsolicited event batch from the AdminBridge GameScript: fan it out to the
            # event consumers rather than the generic GameScript callback.
            if data.get('command') == 'events' and isinstance(data.get('events'), list):
                for event in data['events']:
                    self._dispatch_event(event)
                return
        if self.on_gamescript:
            self.on_gamescript(data)
        else:
            self.log.info(f"GAMESCRIPT: {data}")

    async def receive_ServerDate(self, source, **kwargs): pass
    async def receive_ServerFull(self, source, **kwargs): await self.quit()
    async def receive_ServerBanned(self, source, **kwargs): await self.quit()
    async def receive_ServerShutdown(self, source, **kwargs): await self.quit()
    async def receive_ServerNewGame(self, source, **kwargs): pass
    async def receive_ServerPong(self, source, **kwargs):
        self.log.info(f"Admin: Pong received: {kwargs.get('payload')}")