"""Dashboard aggregate router -- combined endpoint and WebSocket push."""

from __future__ import annotations

import asyncio
import json
import logging
from datetime import datetime, timezone
from typing import Any, Dict, List

from fastapi import APIRouter, WebSocket, WebSocketDisconnect

from server.routers.homeassistant import get_ha
from server.routers.news import get_news_articles
from server.routers.servers import get_servers
from server.routers.tasks import get_tasks
from server.routers.weather import get_weather
from server.services.mqtt_service import mqtt_service

logger = logging.getLogger(__name__)

router = APIRouter(tags=["dashboard"])

# Connected WebSocket clients
clients: List[WebSocket] = []


@router.get("/api/all")
async def get_all() -> Dict[str, Any]:
    """Fetch every data source in parallel and return a single combined dict.

    Response shape::

        {
            "weather":   { ... },
            "news":      { ... },
            "servers":   { ... },
            "ha":        { ... },
            "tasks":     { ... },
            "timestamp": "ISO-8601 string"
        }

    Individual sections that fail will contain ``{"error": true, "message": "..."}``.
    """

    results = await asyncio.gather(
        _safe(get_weather, "weather"),
        _safe(lambda: get_news_articles(limit=20, offset=0, category=None), "news"),
        _safe(get_servers, "servers"),
        _safe(get_ha, "ha"),
        _safe(get_tasks, "tasks"),
    )

    weather_data, news_data, servers_data, ha_data, tasks_data = results

    # Log a concise summary of what worked and what failed
    sections = {"weather": weather_data, "news": news_data, "servers": servers_data,
                "ha": ha_data, "tasks": tasks_data}
    errors = [k for k, v in sections.items() if isinstance(v, dict) and v.get("error")]
    if errors:
        logger.warning("[DASHBOARD] Sections with errors: %s", ", ".join(errors))

    return {
        "weather": weather_data,
        "news": news_data,
        "servers": servers_data,
        "ha": ha_data,
        "tasks": tasks_data,
        "mqtt": {
            "connected": mqtt_service.connected,
            "entities": mqtt_service.get_entities(),
        },
        "timestamp": datetime.now(timezone.utc).isoformat(),
    }


@router.websocket("/ws")
async def ws_endpoint(ws: WebSocket) -> None:
    """WebSocket that pushes fresh dashboard data on every client ping.

    The client should send periodic text messages (e.g. ``"ping"``) to request
    an update.  If no message arrives within 20 seconds the server sends a
    refresh anyway, keeping the connection alive.
    """

    await ws.accept()
    clients.append(ws)
    logger.info("WebSocket client connected (%d total)", len(clients))

    try:
        while True:
            # Wait for a client ping / keepalive; refresh on timeout too.
            try:
                _msg = await asyncio.wait_for(ws.receive_text(), timeout=20.0)
            except asyncio.TimeoutError:
                pass

            # Build and push the latest data
            try:
                data = await get_all()
                await ws.send_json(data)
            except Exception as exc:
                logger.exception("Error sending WebSocket payload")
                # Try to send a lightweight error frame; if that also fails the
                # outer handler will close the connection.
                try:
                    await ws.send_json({"error": True, "message": str(exc)})
                except Exception:
                    break

    except WebSocketDisconnect:
        logger.info("WebSocket client disconnected")
    except Exception as exc:
        logger.exception("Unexpected WebSocket error")
    finally:
        if ws in clients:
            clients.remove(ws)
        logger.info("WebSocket clients remaining: %d", len(clients))


# -- internal helpers ---------------------------------------------------------

async def _safe(coro_or_callable: Any, label: str) -> Dict[str, Any]:
    """Call an async function and return its result, or an error dict."""
    try:
        if asyncio.iscoroutinefunction(coro_or_callable):
            return await coro_or_callable()
        # Support lambdas that return coroutines
        result = coro_or_callable()
        if asyncio.iscoroutine(result):
            return await result
        return result
    except Exception as exc:
        logger.exception("Failed to fetch %s data for dashboard", label)
        return {"error": True, "message": str(exc)}