"""
Bambu Lab Cloud API Service

Handles authentication and profile management with Bambu Lab's cloud services.
"""

import logging
from datetime import datetime, timedelta, timezone

import httpx

logger = logging.getLogger(__name__)

BAMBU_API_BASE = "https://api.bambulab.com"
BAMBU_API_BASE_CN = "https://api.bambulab.cn"


class BambuCloudError(Exception):
    """Base exception for Bambu Cloud errors."""

    pass


class BambuCloudAuthError(BambuCloudError):
    """Authentication related errors."""

    pass


_shared_http_client: httpx.AsyncClient | None = None


def set_shared_http_client(client: httpx.AsyncClient | None) -> None:
    """Register an app-scoped ``httpx.AsyncClient`` so per-request
    ``BambuCloudService`` instances can reuse its connection pool.

    Pass ``None`` during shutdown to unregister. The service only holds a
    reference (never closes a client it does not own), so region + token
    state still stays per-request — this only shares the transport pool.
    """
    global _shared_http_client
    _shared_http_client = client


class BambuCloudService:
    """Service for interacting with Bambu Lab Cloud API."""

    def __init__(self, region: str = "global", client: httpx.AsyncClient | None = None):
        self.base_url = BAMBU_API_BASE if region == "global" else BAMBU_API_BASE_CN
        self.access_token: str | None = None
        self.refresh_token: str | None = None
        self.token_expiry: datetime | None = None
        # Prefer an explicitly-injected client (tests), else fall back to the
        # app-scoped shared client (production), and finally create our own so
        # scripts / tests that skip the lifespan still get a working service.
        if client is not None:
            self._client = client
            self._owns_client = False
        elif _shared_http_client is not None:
            self._client = _shared_http_client
            self._owns_client = False
        else:
            self._client = httpx.AsyncClient(timeout=30.0)
            self._owns_client = True

    @property
    def is_authenticated(self) -> bool:
        """Check if we have a valid token."""
        if not self.access_token:
            return False
        return not (self.token_expiry and datetime.now(timezone.utc) > self.token_expiry)

    def _get_headers(self) -> dict:
        """Get headers for authenticated requests."""
        headers = {
            "Content-Type": "application/json",
            "User-Agent": "Bambuddy/1.0",
        }
        if self.access_token:
            headers["Authorization"] = f"Bearer {self.access_token}"
        return headers

    async def login_request(self, email: str, password: str) -> dict:
        """
        Initiate login - this will trigger either email verification or TOTP prompt.

        Returns dict with login status, verification type, and tfaKey if needed.
        """
        try:
            response = await self._client.post(
                f"{self.base_url}/v1/user-service/user/login",
                headers={"Content-Type": "application/json"},
                json={
                    "account": email,
                    "password": password,
                },
            )

            data = response.json()
            logger.debug(
                f"Login response: status={response.status_code}, loginType={data.get('loginType')}, hasTfaKey={'tfaKey' in data}"
            )

            if response.status_code == 200:
                login_type = data.get("loginType")
                tfa_key = data.get("tfaKey")

                # TOTP authentication required
                if login_type == "tfa" or (tfa_key and login_type != "verifyCode"):
                    return {
                        "success": False,
                        "needs_verification": True,
                        "verification_type": "totp",
                        "tfa_key": tfa_key,
                        "message": "Enter the code from your authenticator app",
                    }

                # Email verification required
                if login_type == "verifyCode":
                    return {
                        "success": False,
                        "needs_verification": True,
                        "verification_type": "email",
                        "tfa_key": None,
                        "message": "Verification code sent to email",
                    }

                # Direct login success (rare, usually needs 2FA)
                if "accessToken" in data:
                    self._set_tokens(data)
                    return {"success": True, "needs_verification": False, "message": "Login successful"}

            # Handle specific error codes
            error_msg = data.get("message") or data.get("error") or "Login failed"
            return {"success": False, "needs_verification": False, "message": error_msg}

        except Exception as e:
            logger.error("Login request failed: %s", e)
            raise BambuCloudAuthError(f"Login request failed: {e}")

    async def verify_code(self, email: str, code: str) -> dict:
        """
        Complete login with email verification code.
        """
        try:
            response = await self._client.post(
                f"{self.base_url}/v1/user-service/user/login",
                headers={"Content-Type": "application/json"},
                json={
                    "account": email,
                    "code": code,
                },
            )

            data = response.json()
            logger.debug("Email verify response: status=%s, hasToken=%s", response.status_code, "accessToken" in data)

            if response.status_code == 200 and "accessToken" in data:
                self._set_tokens(data)
                return {"success": True, "message": "Login successful"}

            return {"success": False, "message": data.get("message", "Verification failed")}

        except Exception as e:
            logger.error("Email verification failed: %s", e)
            raise BambuCloudAuthError(f"Verification failed: {e}")

    async def verify_totp(self, tfa_key: str, code: str) -> dict:
        """
        Complete login with TOTP code from authenticator app.

        Args:
            tfa_key: The tfaKey returned from initial login request
            code: 6-digit TOTP code from authenticator app
        """
        try:
            # TFA endpoint is on bambulab.com, NOT api.bambulab.com
            # Requires browser-like headers to bypass Cloudflare
            tfa_url = "https://bambulab.com/api/sign-in/tfa"
            if "bambulab.cn" in self.base_url:
                tfa_url = "https://bambulab.cn/api/sign-in/tfa"

            browser_headers = {
                "Content-Type": "application/json",
                "User-Agent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36",
                "Accept": "application/json, text/plain, */*",
                "Accept-Language": "en-US,en;q=0.9",
                "Origin": "https://bambulab.com",
                "Referer": "https://bambulab.com/",
            }

            response = await self._client.post(
                tfa_url,
                headers=browser_headers,
                json={
                    "tfaKey": tfa_key,
                    "tfaCode": code,
                },
            )

            logger.debug(
                f"TOTP verify response: status={response.status_code}, body={response.text[:200] if response.text else '(empty)'}"
            )

            # Handle empty response
            if not response.text or not response.text.strip():
                logger.warning("TOTP verification returned empty response (status %s)", response.status_code)
                return {"success": False, "message": "Bambu Cloud returned empty response. Please try again."}

            try:
                data = response.json()
            except Exception as json_err:
                logger.error("Failed to parse TOTP response: %s, body: %s", json_err, response.text[:500])
                return {"success": False, "message": "Invalid response from Bambu Cloud"}

            # Token might be in accessToken, token field, or cookies
            access_token = data.get("accessToken") or data.get("token")

            # Also check cookies for token
            if not access_token:
                for cookie in response.cookies:
                    if "token" in cookie.lower():
                        access_token = response.cookies.get(cookie)
                        break

            if response.status_code == 200 and access_token:
                self.access_token = access_token
                self.refresh_token = data.get("refreshToken")
                from datetime import datetime, timedelta, timezone

                self.token_expiry = datetime.now(timezone.utc) + timedelta(days=30)
                return {"success": True, "message": "Login successful"}

            # Provide helpful error message
            error_msg = data.get("message", "")
            if "expired" in error_msg.lower():
                return {"success": False, "message": "TOTP session expired. Please try logging in again."}
            if not error_msg:
                error_msg = f"TOTP verification failed (status {response.status_code})"

            return {"success": False, "message": error_msg}

        except Exception as e:
            logger.error("TOTP verification failed: %s", e)
            # Return error instead of raising - don't trigger 401/500
            return {"success": False, "message": f"TOTP verification error: {e}"}

    def _set_tokens(self, data: dict):
        """Set tokens from login response."""
        self.access_token = data.get("accessToken")
        self.refresh_token = data.get("refreshToken")
        # Token typically valid for ~3 months, but we'll refresh more often
        self.token_expiry = datetime.now(timezone.utc) + timedelta(days=30)

    def set_token(self, access_token: str):
        """Set access token directly (for stored tokens)."""
        self.access_token = access_token
        self.token_expiry = datetime.now(timezone.utc) + timedelta(days=30)

    def logout(self):
        """Clear authentication state."""
        self.access_token = None
        self.refresh_token = None
        self.token_expiry = None

    async def get_user_profile(self) -> dict:
        """Get user profile information."""
        if not self.is_authenticated:
            raise BambuCloudAuthError("Not authenticated")

        try:
            response = await self._client.get(
                f"{self.base_url}/v1/design-user-service/my/preference", headers=self._get_headers()
            )

            if response.status_code == 200:
                return response.json()

            raise BambuCloudError(f"Failed to get profile: {response.status_code}")

        except httpx.RequestError as e:
            raise BambuCloudError(f"Request failed: {e}")

    async def get_slicer_settings(self, version: str = "02.04.00.70") -> dict:
        """
        Get all slicer settings (filament, printer, process presets).

        Args:
            version: Slicer version string
        """
        if not self.is_authenticated:
            raise BambuCloudAuthError("Not authenticated")

        try:
            response = await self._client.get(
                f"{self.base_url}/v1/iot-service/api/slicer/setting",
                headers=self._get_headers(),
                params={"version": version},
            )

            data = response.json()

            if response.status_code == 200:
                return data

            raise BambuCloudError(f"Failed to get settings: {response.status_code}")

        except httpx.RequestError as e:
            raise BambuCloudError(f"Request failed: {e}")

    async def get_setting_detail(self, setting_id: str) -> dict:
        """Get detailed information for a specific setting/preset."""
        if not self.is_authenticated:
            raise BambuCloudAuthError("Not authenticated")

        try:
            response = await self._client.get(
                f"{self.base_url}/v1/iot-service/api/slicer/setting/{setting_id}", headers=self._get_headers()
            )

            if response.status_code == 200:
                return response.json()

            raise BambuCloudError(f"Failed to get setting detail: {response.status_code}")

        except httpx.RequestError as e:
            raise BambuCloudError(f"Request failed: {e}")

    async def create_setting(
        self, preset_type: str, name: str, base_id: str, setting: dict, version: str = "2.0.0.0"
    ) -> dict:
        """
        Create a new slicer preset/setting.

        Args:
            preset_type: Type of preset - "filament", "print", or "printer"
            name: Display name for the preset
            base_id: Base preset ID to inherit from (e.g., "GFSA00")
            setting: Dict of setting key-value pairs (only modified values from base)
            version: Version string for the preset (default: "2.0.0.0")

        Returns:
            Created preset data including the new setting_id
        """
        if not self.is_authenticated:
            raise BambuCloudAuthError("Not authenticated")

        try:
            # Add timestamp if not present
            import time

            if "updated_time" not in setting:
                setting["updated_time"] = str(int(time.time()))

            payload = {
                "type": preset_type,
                "name": name,
                "version": version,
                "base_id": base_id,
                "setting": setting,
            }

            response = await self._client.post(
                f"{self.base_url}/v1/iot-service/api/slicer/setting", headers=self._get_headers(), json=payload
            )

            data = response.json()

            if response.status_code in (200, 201):
                return data

            error_msg = data.get("message") or data.get("error") or f"HTTP {response.status_code}"
            raise BambuCloudError(f"Failed to create setting: {error_msg}")

        except httpx.RequestError as e:
            raise BambuCloudError(f"Request failed: {e}")

    async def update_setting(self, setting_id: str, name: str | None = None, setting: dict | None = None) -> dict:
        """
        Update an existing slicer preset/setting.

        Note: Bambu Cloud API doesn't support true updates. Instead, we:
        1. Fetch the current setting metadata (type, base_id, version)
        2. Use the provided settings as the new complete settings (NOT merged)
        3. Delete the old setting first (to avoid name conflicts)
        4. Create a new setting via POST

        Args:
            setting_id: ID of the preset to update
            name: New display name (optional)
            setting: Dict of setting key-value pairs - this REPLACES the old settings entirely

        Returns:
            Updated preset data with new setting_id
        """
        if not self.is_authenticated:
            raise BambuCloudAuthError("Not authenticated")

        try:
            # Fetch current setting to get metadata (type, base_id, version)
            current = await self.get_setting_detail(setting_id)
            preset_type = current.get("type", "filament")

            # Use provided settings directly (complete replacement, not merge)
            # This allows the frontend to edit the full settings JSON
            if setting is not None:
                updated_setting = setting.copy()
            else:
                updated_setting = current.get("setting", {}).copy()

            # Extract name from settings_id field in the JSON, or use provided name, or fall back to current
            # The settings_id field contains the name in quotes, e.g., '"My Preset Name"'
            settings_id_key = {
                "filament": "filament_settings_id",
                "print": "print_settings_id",
                "printer": "printer_settings_id",
            }.get(preset_type, "filament_settings_id")

            settings_id_value = updated_setting.get(settings_id_key, "")
            if settings_id_value:
                # Remove surrounding quotes if present (e.g., '"foo"' -> 'foo')
                updated_name = settings_id_value.strip('"')
            elif name is not None:
                updated_name = name
            else:
                updated_name = current.get("name", "Untitled")

            # Update the timestamp
            import time

            updated_setting["updated_time"] = str(int(time.time()))

            # Ensure settings_id field matches the name
            updated_setting[settings_id_key] = f'"{updated_name}"'

            # Delete the old setting FIRST to avoid name conflicts
            await self.delete_setting(setting_id)

            # Create new setting via POST
            payload = {
                "type": preset_type,
                "name": updated_name,
                "version": current.get("version", "2.0.0.0"),
                "base_id": current.get("base_id", ""),
                "setting": updated_setting,
            }

            response = await self._client.post(
                f"{self.base_url}/v1/iot-service/api/slicer/setting", headers=self._get_headers(), json=payload
            )

            data = response.json()

            if response.status_code == 200:
                return data

            error_msg = data.get("message") or data.get("error") or f"HTTP {response.status_code}"
            raise BambuCloudError(f"Failed to update setting: {error_msg}")

        except httpx.RequestError as e:
            raise BambuCloudError(f"Request failed: {e}")

    async def delete_setting(self, setting_id: str) -> dict:
        """
        Delete a slicer preset/setting.

        Args:
            setting_id: ID of the preset to delete

        Returns:
            Deletion confirmation
        """
        if not self.is_authenticated:
            raise BambuCloudAuthError("Not authenticated")

        try:
            response = await self._client.delete(
                f"{self.base_url}/v1/iot-service/api/slicer/setting/{setting_id}", headers=self._get_headers()
            )

            if response.status_code in (200, 204):
                return {"success": True, "message": "Setting deleted"}

            data = response.json() if response.content else {}
            error_msg = data.get("message") or data.get("error") or f"HTTP {response.status_code}"
            raise BambuCloudError(f"Failed to delete setting: {error_msg}")

        except httpx.RequestError as e:
            raise BambuCloudError(f"Request failed: {e}")

    async def get_devices(self) -> dict:
        """Get list of bound devices."""
        if not self.is_authenticated:
            raise BambuCloudAuthError("Not authenticated")

        try:
            response = await self._client.get(
                f"{self.base_url}/v1/iot-service/api/user/bind", headers=self._get_headers()
            )

            if response.status_code == 200:
                return response.json()

            raise BambuCloudError(f"Failed to get devices: {response.status_code}")

        except httpx.RequestError as e:
            raise BambuCloudError(f"Request failed: {e}")

    async def get_firmware_version(self, device_id: str) -> dict:
        """
        Get firmware version info for a device.

        Returns dict with:
        - current_version: Installed firmware version
        - latest_version: Latest available firmware version
        - update_available: Boolean indicating if update is available
        - release_notes: Release notes for latest version
        """
        if not self.is_authenticated:
            raise BambuCloudAuthError("Not authenticated")

        try:
            response = await self._client.get(
                f"{self.base_url}/v1/iot-service/api/user/device/version",
                headers=self._get_headers(),
                params={"device_id": device_id},
            )

            if response.status_code == 200:
                data = response.json()
                # API wraps response in 'data' field
                return data.get("data", data)

            raise BambuCloudError(f"Failed to get firmware version: {response.status_code}")

        except httpx.RequestError as e:
            raise BambuCloudError(f"Request failed: {e}")

    async def close(self):
        """Close the HTTP client we own. No-op when sharing an app-scoped client."""
        if self._owns_client:
            await self._client.aclose()


# Previously this module exposed a process-wide ``_cloud_service`` singleton
# via ``get_cloud_service()`` / ``reset_cloud_service()``. That pattern leaked
# region and token state across users (a China-region login would pin the
# singleton to api.bambulab.cn until the next explicit reset), so the singleton
# has been removed. Callers should construct a per-request
# ``BambuCloudService(region=...)`` from the stored region and ``await
# cloud.close()`` it when done. See ``routes.cloud.build_authenticated_cloud``
# for the standard pattern.