"""
YouTube Data API v3 adapter - collect video mentions from whitelisted channels.
Gracefully skips if YOUTUBE_API_KEY is not configured.
"""

import logging
from datetime import datetime, timedelta, timezone
from typing import Dict, List, Optional

import aiohttp
from sqlalchemy.ext.asyncio import AsyncSession

from app.core.http_client import get_http_session
from sqlalchemy import select

from app.core.config import settings
from app.models.overlay_raw_event import OverlayVideoEvent
from app.models.overlay_registry import YouTubeChannelRegistry
from app.services.overlay.entity_resolver import EntityResolver

logger = logging.getLogger(__name__)

YOUTUBE_SEARCH_URL = "https://www.googleapis.com/youtube/v3/search"
YOUTUBE_VIDEOS_URL = "https://www.googleapis.com/youtube/v3/videos"


class YouTubeAdapter:
    """Collect YouTube video data from whitelisted channels."""

    def __init__(self):
        self.api_key: str = getattr(settings, "YOUTUBE_API_KEY", "")
        self.resolver = EntityResolver()

    @property
    def enabled(self) -> bool:
        return bool(self.api_key)

    async def _get_channels(self, db: AsyncSession) -> List[YouTubeChannelRegistry]:
        result = await db.execute(
            select(YouTubeChannelRegistry).where(YouTubeChannelRegistry.active == True)
        )
        return result.scalars().all()

    async def _search_channel_videos(
        self, channel_id: str, published_after: datetime
    ) -> List[dict]:
        """Search for recent videos from a channel via YouTube Data API."""
        params = {
            "part": "snippet",
            "channelId": channel_id,
            "type": "video",
            "order": "date",
            "publishedAfter": published_after.strftime("%Y-%m-%dT%H:%M:%SZ"),
            "maxResults": 20,
            "key": self.api_key,
        }
        try:
            session = await get_http_session()
            async with session.get(
                YOUTUBE_SEARCH_URL, params=params, timeout=aiohttp.ClientTimeout(total=30)
            ) as resp:
                if resp.status == 403:
                    logger.warning("YouTube API: quota exceeded or invalid key")
                    return []
                resp.raise_for_status()
                data = await resp.json()
            return data.get("items", [])
        except Exception as e:
            logger.error(f"YouTube search error for channel {channel_id}: {e}")
            return []

    async def _get_video_stats(self, video_ids: List[str]) -> Dict[str, Dict]:
        """Fetch view/comment counts for a list of video IDs."""
        if not video_ids:
            return {}
        params = {
            "part": "statistics",
            "id": ",".join(video_ids),
            "key": self.api_key,
        }
        try:
            session = await get_http_session()
            async with session.get(
                YOUTUBE_VIDEOS_URL, params=params, timeout=aiohttp.ClientTimeout(total=30)
            ) as resp:
                resp.raise_for_status()
                data = await resp.json()
            stats = {}
            for item in data.get("items", []):
                vid_id = item["id"]
                s = item.get("statistics", {})
                stats[vid_id] = {
                    "view_count": int(s.get("viewCount", 0)),
                    "comment_count": int(s.get("commentCount", 0)),
                }
            return stats
        except Exception as e:
            logger.error(f"YouTube stats fetch error: {e}")
            return {}

    async def collect(self, db: AsyncSession, days_back: int = 2) -> int:
        """
        Collect YouTube videos from whitelisted channels.

        Gracefully returns 0 if API key is not configured.
        Returns number of new records inserted.
        """
        if not self.enabled:
            logger.info("YouTube adapter: API key not configured, skipping")
            return 0

        await self.resolver.load_aliases(db)
        channels = await self._get_channels(db)
        if not channels:
            logger.info("YouTube: no active channels in registry")
            return 0

        published_after = datetime.now(timezone.utc) - timedelta(days=days_back)
        inserted = 0

        for channel in channels:
            items = await self._search_channel_videos(channel.channel_id, published_after)
            video_ids = [
                item["id"]["videoId"]
                for item in items
                if isinstance(item.get("id"), dict) and "videoId" in item["id"]
            ]
            stats = await self._get_video_stats(video_ids)

            for item in items:
                vid_id = item.get("id", {}).get("videoId") if isinstance(item.get("id"), dict) else None
                if not vid_id:
                    continue

                # Check duplicate
                existing = await db.execute(
                    select(OverlayVideoEvent.id).where(OverlayVideoEvent.video_id == vid_id)
                )
                if existing.first():
                    continue

                snippet = item.get("snippet", {})
                title = snippet.get("title", "")
                pub_at_str = snippet.get("publishedAt", "")
                try:
                    pub_at = datetime.fromisoformat(pub_at_str.replace("Z", "+00:00"))
                except Exception:
                    pub_at = datetime.now(timezone.utc)

                stat = stats.get(vid_id, {})
                matched = self.resolver.resolve_from_title(title)

                event = OverlayVideoEvent(
                    video_id=vid_id,
                    channel_id=channel.channel_id,
                    title=title,
                    view_count=stat.get("view_count", 0),
                    comment_count=stat.get("comment_count", 0),
                    published_at=pub_at,
                    matched_symbols=matched,
                    channel_weight=channel.channel_weight,
                )
                db.add(event)
                inserted += 1

        if inserted:
            await db.commit()
            logger.info(f"YouTube: inserted {inserted} video events")

        return inserted