from __future__ import annotations

import asyncio
from dataclasses import dataclass
from enum import IntEnum
from typing import Optional

from bleak import BleakClient, BleakScanner


LEGO_MANUFACTURER_ID = 0x0397
DUPLO_HUB_ID = 0x20

LEGO_HUB_SERVICE_UUID = "00001623-1212-efde-1623-785feabcd123"
LEGO_HUB_CHARACTERISTIC_UUID = "00001624-1212-efde-1623-785feabcd123"


class DuploColor(IntEnum):
    BLACK = 0
    PINK = 1
    PURPLE = 2
    BLUE = 3
    LIGHTBLUE = 4
    CYAN = 5
    GREEN = 6
    YELLOW = 7
    ORANGE = 8
    RED = 9
    WHITE = 10


class DuploSound(IntEnum):
    BRAKE = 3
    STATION_DEPARTURE = 5
    WATER_REFILL = 7
    HORN = 9
    STEAM = 10


@dataclass
class DuploPorts:
    MOTOR: int = 0x00
    SPEAKER: int = 0x01
    LED: int = 0x11


class DuploTrainHub:
    def __init__(self, address: Optional[str] = None, timeout: float = 10.0) -> None:
        self._address = address
        self._timeout = timeout
        self._client: Optional[BleakClient] = None
        self.ports = DuploPorts()

    @property
    def is_connected(self) -> bool:
        return self._client is not None and self._client.is_connected

    async def connect(self) -> None:
        if self.is_connected:
            return

        if not self._address:
            self._address = await self._discover_duplo_hub()

        self._client = BleakClient(self._address, timeout=self._timeout)
        await self._client.connect()

    async def disconnect(self) -> None:
        if self._client is not None:
            await self._client.disconnect()
        self._client = None

    async def __aenter__(self) -> "DuploTrainHub":
        await self.connect()
        return self

    async def __aexit__(self, exc_type, exc, tb) -> None:
        await self.disconnect()

    async def set_motor_speed(self, speed: int) -> None:
        mapped = self._clamp(speed, -100, 100)
        payload = bytes([0x81, self.ports.MOTOR, 0x11, 0x51, 0x00, mapped & 0xFF])
        await self._write(payload)

    async def forward(self, speed: int = 50) -> None:
        await self.set_motor_speed(abs(speed))

    async def backward(self, speed: int = 50) -> None:
        await self.set_motor_speed(-abs(speed))

    async def stop(self) -> None:
        await self.set_motor_speed(0)

    async def set_light(self, color: DuploColor) -> None:
        set_color_mode = bytes([0x41, self.ports.LED, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00])
        set_color = bytes([0x81, self.ports.LED, 0x11, 0x51, 0x00, int(color) & 0xFF])
        await self._write(set_color_mode)
        await asyncio.sleep(0.05)
        await self._write(set_color)

    async def change_light_color(self, color: DuploColor) -> None:
        await self.set_light(color)

    async def turn_off_light(self) -> None:
        await self.set_light(DuploColor.BLACK)

    async def play_sound(self, sound: DuploSound) -> None:
        set_sound_mode = bytes([0x41, self.ports.SPEAKER, 0x01, 0x01, 0x00, 0x00, 0x00, 0x01])
        play_sound = bytes([0x81, self.ports.SPEAKER, 0x11, 0x51, 0x01, int(sound) & 0xFF])
        await self._write(set_sound_mode)
        await asyncio.sleep(0.05)
        await self._write(play_sound)

    async def play_tone(self, tone_number: int) -> None:
        tone = self._clamp(tone_number, 0, 10)
        set_tone_mode = bytes([0x41, self.ports.SPEAKER, 0x02, 0x01, 0x00, 0x00, 0x00, 0x01])
        play_tone = bytes([0x81, self.ports.SPEAKER, 0x11, 0x51, 0x02, tone & 0xFF])
        await self._write(set_tone_mode)
        await asyncio.sleep(0.05)
        await self._write(play_tone)

    async def demo(self) -> None:
        await self.set_light(DuploColor.GREEN)
        await self.forward(40)
        await asyncio.sleep(2)
        await self.stop()
        await self.play_sound(DuploSound.HORN)

    async def _write(self, payload: bytes) -> None:
        if not self.is_connected or self._client is None:
            raise RuntimeError("Hub non connecté. Appelez connect() avant.")
        framed_payload = self._frame_message(payload)
        await self._client.write_gatt_char(LEGO_HUB_CHARACTERISTIC_UUID, framed_payload, response=True)

    @staticmethod
    def _frame_message(message_without_header: bytes) -> bytes:
        message_length = len(message_without_header) + 2
        if message_length > 127:
            raise ValueError("Message trop long pour l'encodage court LEGO BLE.")
        return bytes([message_length, 0x00]) + message_without_header

    async def _discover_duplo_hub(self) -> str:
        candidates: list[tuple[object, dict]] = []

        try:
            discovered = await BleakScanner.discover(timeout=self._timeout, return_adv=True)
            for _, value in discovered.items():
                device, adv = value
                candidates.append((device, getattr(adv, "manufacturer_data", {}) or {}))
        except TypeError:
            devices = await BleakScanner.discover(timeout=self._timeout)
            for device in devices:
                metadata = getattr(device, "metadata", {}) or {}
                candidates.append((device, metadata.get("manufacturer_data", {}) or {}))

        for device, manufacturer_data in candidates:
            manu = manufacturer_data.get(LEGO_MANUFACTURER_ID)
            name = getattr(device, "name", "") or ""
            address = getattr(device, "address", None)
            if not address:
                continue
            if manu and len(manu) >= 2 and manu[1] == DUPLO_HUB_ID:
                return address
            if "duplo" in name.lower():
                return address
        raise RuntimeError("Aucun hub DUPLO détecté. Vérifiez qu'il est allumé et en mode appairage.")

    @staticmethod
    def _clamp(value: int, minimum: int, maximum: int) -> int:
        return max(minimum, min(maximum, int(value)))