"""Media player platform for Remote Media Player integration."""

from __future__ import annotations

import asyncio
import logging
from datetime import datetime, timedelta
from typing import Any

from homeassistant.components.media_player import (
    BrowseMedia,
    MediaPlayerEntity,
    MediaPlayerEntityFeature,
    MediaPlayerState,
    MediaType,
)
from homeassistant.components.media_player.const import (
    MediaClass,
)
from urllib.parse import quote, unquote
from homeassistant.config_entries import ConfigEntry
from homeassistant.const import CONF_NAME
from homeassistant.core import HomeAssistant, callback
from homeassistant.helpers.entity import DeviceInfo
from homeassistant.helpers.entity_platform import AddEntitiesCallback
from homeassistant.helpers.update_coordinator import (
    CoordinatorEntity,
    DataUpdateCoordinator,
    UpdateFailed,
)

from .api_client import MediaServerClient, MediaServerError, MediaServerWebSocket
from .const import (
    DOMAIN,
    CONF_HOST,
    CONF_PORT,
    CONF_TOKEN,
    CONF_POLL_INTERVAL,
    CONF_USE_WEBSOCKET,
    DEFAULT_POLL_INTERVAL,
    DEFAULT_NAME,
    DEFAULT_USE_WEBSOCKET,
    DEFAULT_RECONNECT_INTERVAL,
)

_LOGGER = logging.getLogger(__name__)


async def async_setup_entry(
    hass: HomeAssistant,
    entry: ConfigEntry,
    async_add_entities: AddEntitiesCallback,
) -> None:
    """Set up the media player platform.

    Args:
        hass: Home Assistant instance
        entry: Config entry
        async_add_entities: Callback to add entities
    """
    _LOGGER.debug("Setting up media player platform for %s", entry.entry_id)

    try:
        client: MediaServerClient = hass.data[DOMAIN][entry.entry_id]["client"]
    except KeyError:
        _LOGGER.error("Client not found in hass.data for entry %s", entry.entry_id)
        return

    # Get poll interval from options or data
    poll_interval = entry.options.get(
        CONF_POLL_INTERVAL,
        entry.data.get(CONF_POLL_INTERVAL, DEFAULT_POLL_INTERVAL),
    )

    # Get WebSocket setting from options or data
    use_websocket = entry.options.get(
        CONF_USE_WEBSOCKET,
        entry.data.get(CONF_USE_WEBSOCKET, DEFAULT_USE_WEBSOCKET),
    )

    # Create update coordinator with WebSocket support
    coordinator = MediaPlayerCoordinator(
        hass,
        client,
        poll_interval,
        host=entry.data[CONF_HOST],
        port=entry.data[CONF_PORT],
        token=entry.data[CONF_TOKEN],
        use_websocket=use_websocket,
        entry=entry,
    )

    # Set up WebSocket connection if enabled
    await coordinator.async_setup()

    # Fetch initial data - don't fail setup if this fails
    try:
        await coordinator.async_config_entry_first_refresh()
    except Exception as err:
        _LOGGER.warning("Initial data fetch failed, will retry: %s", err)
        # Continue anyway - the coordinator will retry

    # Store coordinator for cleanup
    hass.data[DOMAIN][entry.entry_id]["coordinator"] = coordinator

    # Create and add entity
    entity = RemoteMediaPlayerEntity(
        coordinator,
        entry,
    )
    _LOGGER.info("Adding media player entity: %s", entity.unique_id)
    async_add_entities([entity])


class MediaPlayerCoordinator(DataUpdateCoordinator[dict[str, Any]]):
    """Coordinator for fetching media player data with WebSocket support."""

    def __init__(
        self,
        hass: HomeAssistant,
        client: MediaServerClient,
        poll_interval: int,
        host: str,
        port: int,
        token: str,
        use_websocket: bool = True,
        entry: ConfigEntry | None = None,
    ) -> None:
        """Initialize the coordinator.

        Args:
            hass: Home Assistant instance
            client: Media Server API client
            poll_interval: Update interval in seconds
            host: Server hostname
            port: Server port
            token: API token
            use_websocket: Whether to use WebSocket for updates
            entry: Config entry (for integration reload on scripts change)
        """
        super().__init__(
            hass,
            _LOGGER,
            name="Remote Media Player",
            update_interval=timedelta(seconds=poll_interval),
        )
        self.client = client
        self._host = host
        self._port = port
        self._token = token
        self._use_websocket = use_websocket
        self._entry = entry
        self._ws_client: MediaServerWebSocket | None = None
        self._ws_connected = False
        self._reconnect_task: asyncio.Task | None = None
        self._poll_interval = poll_interval

    async def async_setup(self) -> None:
        """Set up the coordinator with WebSocket if enabled."""
        if self._use_websocket:
            await self._connect_websocket()

    async def _connect_websocket(self) -> None:
        """Establish WebSocket connection."""
        if self._ws_client:
            await self._ws_client.disconnect()

        self._ws_client = MediaServerWebSocket(
            host=self._host,
            port=self._port,
            token=self._token,
            on_status_update=self._handle_ws_status_update,
            on_disconnect=self._handle_ws_disconnect,
            on_scripts_changed=self._handle_ws_scripts_changed,
        )

        if await self._ws_client.connect():
            self._ws_connected = True
            # Disable polling - WebSocket handles all updates including position
            self.update_interval = None
            _LOGGER.info("WebSocket connected, polling disabled")
        else:
            self._ws_connected = False
            # Keep polling as fallback
            self.update_interval = timedelta(seconds=self._poll_interval)
            _LOGGER.warning("WebSocket failed, falling back to polling")
            # Schedule reconnect attempt
            self._schedule_reconnect()

    @callback
    def _handle_ws_status_update(self, status_data: dict[str, Any]) -> None:
        """Handle status update from WebSocket."""
        self.async_set_updated_data(status_data)

    @callback
    def _handle_ws_disconnect(self) -> None:
        """Handle WebSocket disconnection."""
        self._ws_connected = False
        # Re-enable polling as fallback
        self.update_interval = timedelta(seconds=self._poll_interval)
        _LOGGER.warning("WebSocket disconnected, falling back to polling")
        # Trigger an immediate refresh to restart the polling loop.
        # Without this, the polling loop stays stopped (it was disabled when
        # WebSocket was active) and the entity never becomes unavailable.
        self.hass.async_create_task(self.async_request_refresh())
        # Schedule reconnect attempt
        self._schedule_reconnect()

    @callback
    def _handle_ws_scripts_changed(self) -> None:
        """Handle scripts changed notification from WebSocket."""
        if self._entry:
            _LOGGER.info("Scripts changed, reloading integration")
            self.hass.async_create_task(
                self.hass.config_entries.async_reload(self._entry.entry_id)
            )
        else:
            _LOGGER.warning("Cannot reload integration: entry not available")

    def _schedule_reconnect(self) -> None:
        """Schedule a WebSocket reconnection attempt."""
        if self._reconnect_task and not self._reconnect_task.done():
            return  # Already scheduled

        async def reconnect() -> None:
            await asyncio.sleep(DEFAULT_RECONNECT_INTERVAL)
            if self._use_websocket and not self._ws_connected:
                _LOGGER.info("Attempting WebSocket reconnect...")
                await self._connect_websocket()

        self._reconnect_task = self.hass.async_create_task(reconnect())

    async def _async_update_data(self) -> dict[str, Any]:
        """Fetch data from the API (fallback when WebSocket unavailable).

        Returns:
            Media status data

        Raises:
            UpdateFailed: On API errors
        """
        try:
            data = await self.client.get_status()
            _LOGGER.debug("HTTP poll received status: %s", data.get("state"))
            return data
        except MediaServerError as err:
            raise UpdateFailed(f"Error communicating with server: {err}") from err
        except Exception as err:
            _LOGGER.exception("Unexpected error fetching media status")
            raise UpdateFailed(f"Unexpected error: {err}") from err

    async def async_shutdown(self) -> None:
        """Clean up resources."""
        if self._reconnect_task:
            self._reconnect_task.cancel()
            try:
                await self._reconnect_task
            except asyncio.CancelledError:
                pass
        if self._ws_client:
            await self._ws_client.disconnect()


class RemoteMediaPlayerEntity(CoordinatorEntity[MediaPlayerCoordinator], MediaPlayerEntity):
    """Representation of a Remote Media Player."""

    _attr_has_entity_name = True
    _attr_name = None

    @property
    def available(self) -> bool:
        """Return True if entity is available."""
        # Use the coordinator's last_update_success to detect server availability
        return self.coordinator.last_update_success

    def __init__(
        self,
        coordinator: MediaPlayerCoordinator,
        entry: ConfigEntry,
    ) -> None:
        """Initialize the media player entity.

        Args:
            coordinator: Data update coordinator
            entry: Config entry
        """
        super().__init__(coordinator)
        self._entry = entry
        self._attr_unique_id = f"{entry.entry_id}_media_player"

        # Device info - must match button.py identifiers
        self._attr_device_info = DeviceInfo(
            identifiers={(DOMAIN, entry.entry_id)},
            name=entry.title,
            manufacturer="Remote Media Player",
            model="Media Server",
            sw_version="1.0.0",
            configuration_url=f"http://{entry.data[CONF_HOST]}:{int(entry.data[CONF_PORT])}/docs",
        )

    @property
    def supported_features(self) -> MediaPlayerEntityFeature:
        """Return the supported features."""
        return (
            MediaPlayerEntityFeature.PAUSE
            | MediaPlayerEntityFeature.PLAY
            | MediaPlayerEntityFeature.STOP
            | MediaPlayerEntityFeature.VOLUME_SET
            | MediaPlayerEntityFeature.VOLUME_MUTE
            | MediaPlayerEntityFeature.PREVIOUS_TRACK
            | MediaPlayerEntityFeature.NEXT_TRACK
            | MediaPlayerEntityFeature.SEEK
            | MediaPlayerEntityFeature.TURN_ON
            | MediaPlayerEntityFeature.TURN_OFF
            | MediaPlayerEntityFeature.BROWSE_MEDIA
            | MediaPlayerEntityFeature.PLAY_MEDIA
        )

    @property
    def state(self) -> MediaPlayerState | None:
        """Return the state of the player."""
        if self.coordinator.data is None:
            return MediaPlayerState.OFF

        state = self.coordinator.data.get("state", "idle")
        state_map = {
            "playing": MediaPlayerState.PLAYING,
            "paused": MediaPlayerState.PAUSED,
            "stopped": MediaPlayerState.IDLE,
            "idle": MediaPlayerState.IDLE,
        }
        return state_map.get(state, MediaPlayerState.IDLE)

    @property
    def volume_level(self) -> float | None:
        """Return the volume level (0..1)."""
        if self.coordinator.data is None:
            return None
        volume = self.coordinator.data.get("volume", 0)
        return volume / 100.0

    @property
    def is_volume_muted(self) -> bool | None:
        """Return True if volume is muted."""
        if self.coordinator.data is None:
            return None
        return self.coordinator.data.get("muted", False)

    @property
    def media_content_type(self) -> MediaType | None:
        """Return the content type of current playing media."""
        return MediaType.MUSIC

    @property
    def media_title(self) -> str | None:
        """Return the title of current playing media."""
        if self.coordinator.data is None:
            return None
        return self.coordinator.data.get("title")

    @property
    def media_artist(self) -> str | None:
        """Return the artist of current playing media."""
        if self.coordinator.data is None:
            return None
        return self.coordinator.data.get("artist")

    @property
    def media_album_name(self) -> str | None:
        """Return the album name of current playing media."""
        if self.coordinator.data is None:
            return None
        return self.coordinator.data.get("album")

    @property
    def media_image_url(self) -> str | None:
        """Return the image URL of current playing media."""
        if self.coordinator.data is None:
            return None
        return self.coordinator.data.get("album_art_url")

    @property
    def media_duration(self) -> int | None:
        """Return the duration of current playing media in seconds."""
        if self.coordinator.data is None:
            return None
        duration = self.coordinator.data.get("duration")
        if duration is None:
            return None
        try:
            return int(duration)
        except (ValueError, TypeError):
            return None

    @property
    def media_position(self) -> int | None:
        """Return the position of current playing media in seconds."""
        if self.coordinator.data is None:
            return None
        position = self.coordinator.data.get("position")
        if position is None:
            return None
        try:
            return int(position)
        except (ValueError, TypeError):
            return None

    @property
    def media_position_updated_at(self) -> datetime | None:
        """Return when the position was last updated."""
        if self.coordinator.data is None:
            return None
        if self.coordinator.data.get("position") is not None:
            # Use last_update_success_time if available, otherwise use current time
            if hasattr(self.coordinator, 'last_update_success_time'):
                return self.coordinator.last_update_success_time
            return datetime.now()
        return None

    @property
    def source(self) -> str | None:
        """Return the current media source."""
        if self.coordinator.data is None:
            return None
        return self.coordinator.data.get("source")

    async def async_media_play(self) -> None:
        """Send play command."""
        try:
            await self.coordinator.client.play()
            await self.coordinator.async_request_refresh()
        except MediaServerError as err:
            _LOGGER.error("Failed to play: %s", err)

    async def async_media_pause(self) -> None:
        """Send pause command."""
        try:
            await self.coordinator.client.pause()
            await self.coordinator.async_request_refresh()
        except MediaServerError as err:
            _LOGGER.error("Failed to pause: %s", err)

    async def async_media_stop(self) -> None:
        """Send stop command."""
        try:
            await self.coordinator.client.stop()
            await self.coordinator.async_request_refresh()
        except MediaServerError as err:
            _LOGGER.error("Failed to stop: %s", err)

    async def async_media_next_track(self) -> None:
        """Send next track command."""
        try:
            await self.coordinator.client.next_track()
            await self.coordinator.async_request_refresh()
        except MediaServerError as err:
            _LOGGER.error("Failed to skip to next track: %s", err)

    async def async_media_previous_track(self) -> None:
        """Send previous track command."""
        try:
            await self.coordinator.client.previous_track()
            await self.coordinator.async_request_refresh()
        except MediaServerError as err:
            _LOGGER.error("Failed to go to previous track: %s", err)

    async def async_set_volume_level(self, volume: float) -> None:
        """Set volume level, range 0..1."""
        try:
            await self.coordinator.client.set_volume(int(volume * 100))
            await self.coordinator.async_request_refresh()
        except MediaServerError as err:
            _LOGGER.error("Failed to set volume: %s", err)

    async def async_mute_volume(self, mute: bool) -> None:
        """Mute/unmute the volume."""
        try:
            # Toggle mute (API toggles, so call it if state differs)
            if self.is_volume_muted != mute:
                await self.coordinator.client.toggle_mute()
                await self.coordinator.async_request_refresh()
        except MediaServerError as err:
            _LOGGER.error("Failed to toggle mute: %s", err)

    async def async_media_seek(self, position: float) -> None:
        """Seek to a position."""
        try:
            await self.coordinator.client.seek(position)
            await self.coordinator.async_request_refresh()
        except MediaServerError as err:
            _LOGGER.error("Failed to seek: %s", err)

    async def async_turn_on(self) -> None:
        """Send turn on command."""
        try:
            await self.coordinator.client.turn_on()
        except MediaServerError as err:
            _LOGGER.error("Failed to turn on: %s", err)

    async def async_turn_off(self) -> None:
        """Send turn off command."""
        try:
            await self.coordinator.client.turn_off()
        except MediaServerError as err:
            _LOGGER.error("Failed to turn off: %s", err)

    async def async_toggle(self) -> None:
        """Send toggle command."""
        try:
            await self.coordinator.client.toggle()
        except MediaServerError as err:
            _LOGGER.error("Failed to toggle: %s", err)

    # Media Browser support

    @staticmethod
    def _encode_media_id(folder_id: str, path: str = "") -> str:
        """Encode folder_id and path into media_content_id.

        Format: folder_id|encoded_path
        Root folder: folder_id|
        """
        return f"{folder_id}|{quote(path, safe='')}"

    @staticmethod
    def _decode_media_id(media_content_id: str) -> tuple[str, str]:
        """Decode media_content_id into folder_id and path.

        Returns:
            Tuple of (folder_id, path)
        """
        if not media_content_id or "|" not in media_content_id:
            return "", ""
        folder_id, encoded_path = media_content_id.split("|", 1)
        path = unquote(encoded_path) if encoded_path else ""
        return folder_id, path

    async def async_browse_media(
        self,
        media_content_type: str | None = None,
        media_content_id: str | None = None,
    ) -> BrowseMedia:
        """Implement the media browsing.

        Args:
            media_content_type: Type of media (unused, but required by HA)
            media_content_id: ID in format "folder_id|path" or None for root

        Returns:
            BrowseMedia object with children
        """
        _LOGGER.debug("Browse media: type=%s, id=%s", media_content_type, media_content_id)

        # Root level - list all folders
        if not media_content_id:
            folders = await self.coordinator.client.get_media_folders()

            children = [
                BrowseMedia(
                    title=config["label"],
                    media_class=MediaClass.DIRECTORY,
                    media_content_type=MediaType.MUSIC,  # All folders show as music
                    media_content_id=self._encode_media_id(folder_id, ""),
                    can_play=False,
                    can_expand=True,
                )
                for folder_id, config in folders.items()
                if config.get("enabled", True)
            ]

            return BrowseMedia(
                title="Media Folders",
                media_class=MediaClass.DIRECTORY,
                media_content_type=MediaType.MUSIC,
                media_content_id="",
                can_play=False,
                can_expand=True,
                children=children,
            )

        # Browse specific folder
        folder_id, path = self._decode_media_id(media_content_id)

        if not folder_id:
            raise ValueError("Invalid media_content_id format")

        # Get folder contents from API
        browse_data = await self.coordinator.client.browse_folder(folder_id, path, offset=0, limit=5000)

        # Fetch folder metadata once (not per-item) for building absolute paths
        folders = await self.coordinator.client.get_media_folders()
        base_path = folders.get(folder_id, {}).get("path", "")
        # Detect path separator from server's base_path (Unix vs Windows)
        separator = '\\' if '\\' in base_path else '/'
        base_path_clean = base_path.rstrip('/\\')

        children = []
        for item in browse_data.get("items", []):
            if item["type"] == "folder":
                # Subfolder
                item_path = f"{path}/{item['name']}" if path else item['name']
                children.append(
                    BrowseMedia(
                        title=item["name"],
                        media_class=MediaClass.DIRECTORY,
                        media_content_type=MediaType.MUSIC,
                        media_content_id=self._encode_media_id(folder_id, item_path),
                        can_play=False,
                        can_expand=True,
                    )
                )
            elif item.get("is_media", False):
                # Media file - build absolute path for playback
                file_path_in_folder = f"{path}/{item['name']}" if path else item['name']
                absolute_path = f"{base_path_clean}{separator}{file_path_in_folder.replace('/', separator)}"

                children.append(
                    BrowseMedia(
                        title=item["name"],
                        media_class=MediaClass.MUSIC,
                        media_content_type=MediaType.MUSIC,
                        media_content_id=absolute_path,  # Use absolute path as ID for playback
                        can_play=True,
                        can_expand=False,
                    )
                )

        # Get current folder label
        current_title = path.split("/")[-1] if path else browse_data.get("label", folder_id)

        return BrowseMedia(
            title=current_title,
            media_class=MediaClass.DIRECTORY,
            media_content_type=MediaType.MUSIC,
            media_content_id=media_content_id,
            can_play=False,
            can_expand=True,
            children=children,
        )

    async def async_play_media(
        self, media_type: str, media_id: str, **kwargs: Any
    ) -> None:
        """Play a media file.

        Args:
            media_type: Type of media (unused)
            media_id: Absolute file path to media file
            **kwargs: Additional arguments (unused)
        """
        _LOGGER.debug("Play media: type=%s, id=%s", media_type, media_id)

        try:
            # media_id is the absolute file path from browse_media
            await self.coordinator.client.play_media_file(media_id)

            # Request immediate status update
            await self.coordinator.async_request_refresh()
        except MediaServerError as err:
            _LOGGER.error("Failed to play media file: %s", err)