"""Storage helpers for Immich Album Watcher."""

from __future__ import annotations

import logging
from datetime import datetime, timezone
from typing import Any

from homeassistant.core import HomeAssistant
from homeassistant.helpers.storage import Store

from immich_watcher_core.notifications.queue import (
    NotificationQueue as CoreNotificationQueue,
)
from immich_watcher_core.telegram.cache import TelegramFileCache as CoreTelegramFileCache

_LOGGER = logging.getLogger(__name__)

STORAGE_VERSION = 1
STORAGE_KEY_PREFIX = "immich_album_watcher"


class HAStorageBackend:
    """Home Assistant storage backend adapter.

    Wraps homeassistant.helpers.storage.Store to satisfy the
    StorageBackend protocol from immich_watcher_core.
    """

    def __init__(self, hass: HomeAssistant, key: str) -> None:
        """Initialize with HA store.

        Args:
            hass: Home Assistant instance
            key: Storage key (e.g. "immich_album_watcher.telegram_cache.xxx")
        """
        self._store: Store[dict[str, Any]] = Store(hass, STORAGE_VERSION, key)

    async def load(self) -> dict[str, Any] | None:
        """Load data from HA storage."""
        return await self._store.async_load()

    async def save(self, data: dict[str, Any]) -> None:
        """Save data to HA storage."""
        await self._store.async_save(data)

    async def remove(self) -> None:
        """Remove all stored data."""
        await self._store.async_remove()


class ImmichAlbumStorage:
    """Handles persistence of album state across restarts.

    This remains HA-native as it manages HA-specific album tracking state.
    """

    def __init__(self, hass: HomeAssistant, entry_id: str) -> None:
        """Initialize the storage."""
        self._store: Store[dict[str, Any]] = Store(
            hass, STORAGE_VERSION, f"{STORAGE_KEY_PREFIX}.{entry_id}"
        )
        self._data: dict[str, Any] | None = None

    async def async_load(self) -> dict[str, Any]:
        """Load data from storage."""
        self._data = await self._store.async_load() or {"albums": {}}
        _LOGGER.debug("Loaded storage data with %d albums", len(self._data.get("albums", {})))
        return self._data

    async def async_save_album_state(self, album_id: str, asset_ids: set[str]) -> None:
        """Save album asset IDs to storage."""
        if self._data is None:
            self._data = {"albums": {}}

        self._data["albums"][album_id] = {
            "asset_ids": list(asset_ids),
            "last_updated": datetime.now(timezone.utc).isoformat(),
        }
        await self._store.async_save(self._data)

    def get_album_asset_ids(self, album_id: str) -> set[str] | None:
        """Get persisted asset IDs for an album.

        Returns None if no persisted state exists for the album.
        """
        if self._data and "albums" in self._data:
            album_data = self._data["albums"].get(album_id)
            if album_data:
                return set(album_data.get("asset_ids", []))
        return None

    async def async_remove_album(self, album_id: str) -> None:
        """Remove an album from storage."""
        if self._data and "albums" in self._data:
            self._data["albums"].pop(album_id, None)
            await self._store.async_save(self._data)

    async def async_remove(self) -> None:
        """Remove all storage data."""
        await self._store.async_remove()
        self._data = None


# Convenience factory functions for creating core classes with HA backends


def create_telegram_cache(
    hass: HomeAssistant,
    entry_id: str,
    ttl_seconds: int = 48 * 60 * 60,
    use_thumbhash: bool = False,
) -> CoreTelegramFileCache:
    """Create a TelegramFileCache with HA storage backend.

    Args:
        hass: Home Assistant instance
        entry_id: Config entry ID for scoping
        ttl_seconds: TTL for cache entries (TTL mode only)
        use_thumbhash: Use thumbhash validation instead of TTL
    """
    suffix = f"_assets" if use_thumbhash else ""
    backend = HAStorageBackend(
        hass, f"{STORAGE_KEY_PREFIX}.telegram_cache.{entry_id}{suffix}"
    )
    return CoreTelegramFileCache(backend, ttl_seconds=ttl_seconds, use_thumbhash=use_thumbhash)


def create_notification_queue(
    hass: HomeAssistant, entry_id: str
) -> CoreNotificationQueue:
    """Create a NotificationQueue with HA storage backend."""
    backend = HAStorageBackend(
        hass, f"{STORAGE_KEY_PREFIX}.notification_queue.{entry_id}"
    )
    return CoreNotificationQueue(backend)


# Re-export core types for backward compatibility
TelegramFileCache = CoreTelegramFileCache
NotificationQueue = CoreNotificationQueue