from __future__ import annotations

import base64
import hashlib
import hmac
import json
import time
import urllib.error
import urllib.request
import uuid
from typing import Any


BASE_URL = "https://api.switch-bot.com/v1.1"


class SwitchBotError(RuntimeError):
    pass


class SwitchBotClient:
    def __init__(self, token: str, secret: str) -> None:
        self.token = token
        self.secret = secret

    def _headers(self) -> dict[str, str]:
        timestamp_ms = str(int(time.time() * 1000))
        nonce = str(uuid.uuid4())
        message = f"{self.token}{timestamp_ms}{nonce}".encode("utf-8")
        digest = hmac.new(self.secret.encode("utf-8"), message, hashlib.sha256).digest()
        signature = base64.b64encode(digest).decode("utf-8")
        return {
            "Authorization": self.token,
            "Content-Type": "application/json; charset=utf8",
            "sign": signature,
            "t": timestamp_ms,
            "nonce": nonce,
        }

    def get(self, path: str) -> dict[str, Any]:
        endpoint = path if path.startswith("/") else f"/{path}"
        request = urllib.request.Request(
            f"{BASE_URL}{endpoint}",
            headers=self._headers(),
            method="GET",
        )
        try:
            with urllib.request.urlopen(request, timeout=20) as response:
                body = response.read().decode("utf-8")
        except urllib.error.HTTPError as exc:
            details = exc.read().decode("utf-8", errors="replace")
            raise SwitchBotError(f"HTTP {exc.code}: {details}") from exc
        except urllib.error.URLError as exc:
            raise SwitchBotError(f"Could not reach SwitchBot API: {exc.reason}") from exc

        try:
            payload = json.loads(body)
        except json.JSONDecodeError as exc:
            raise SwitchBotError(f"SwitchBot returned invalid JSON: {body}") from exc

        if payload.get("statusCode") != 100:
            raise SwitchBotError(f"SwitchBot API error: {payload}")
        return payload

    def devices(self) -> list[dict[str, Any]]:
        payload = self.get("/devices")
        body = payload.get("body", {})
        return body.get("deviceList", [])

    def status(self, device_id: str) -> dict[str, Any]:
        payload = self.get(f"/devices/{device_id}/status")
        return payload.get("body", {})