from __future__ import annotations

import asyncio
import html
import json
import os
from pathlib import Path
from typing import Any

from aiogram.types import FSInputFile

from vk_parser_app.constants import MEDIA_STATUS_FAILED, MEDIA_STATUS_LINK_ONLY
from vk_parser_app.db import get_pool
from vk_parser_app.workers.vk_storage_uploader import TMP_DIR, TMP_PREFIX, TelegramStorageUploader


def jlog(event: str, **payload: Any) -> None:
    print(json.dumps({"event": event, **payload}, ensure_ascii=False, default=str), flush=True)


async def load_pending_videos(worker: TelegramStorageUploader, limit: int) -> list[dict[str, Any]]:
    rows = await worker.pool.fetch(
        """
        SELECT m.*, rp.original_url AS post_url
        FROM raw_post_media m
        JOIN raw_posts rp ON rp.id=m.raw_post_id
        WHERE m.media_type='video'
          AND m.status='pending'
          AND COALESCE(m.tg_file_id, m.storage_attachment_id, '') = ''
          AND COALESCE(m.error, '') ILIKE '%timeout%'
          AND COALESCE(m.duration_sec, 0) <= $1
        ORDER BY COALESCE(rp.publication_status, 'pending')='published', m.id DESC
        LIMIT $2
        """,
        worker.video_max_duration_sec,
        limit,
    )
    return [dict(row) for row in rows]


async def send_video_to_storage(worker: TelegramStorageUploader, media: dict[str, Any], path: str) -> None:
    caption = (
        f"Backfill video media #{int(media['id'])} for raw_post #{int(media['raw_post_id'])}\n"
        f'<a href="{html.escape(str(media.get("post_url") or ""), quote=True)}">source post</a>'
    )
    message = await worker.tg_retry(
        lambda: worker.bot.send_video(
            video=FSInputFile(path, filename=f"video_{int(media['id'])}.mp4"),
            caption=caption[: worker.caption_limit],
            parse_mode="HTML",
            **worker.chat_kwargs(),
        )
    )
    if not message.video:
        raise RuntimeError("Telegram accepted message without video payload")
    await worker.mark_media_uploaded(int(media["id"]), message.video.file_id, message.video.file_unique_id)


async def main() -> None:
    limit = int(os.getenv("BACKFILL_LIMIT", "200"))
    worker = TelegramStorageUploader()
    await worker.init()
    videos = await load_pending_videos(worker, limit)
    jlog("start", count=len(videos), limit=limit)
    ok = 0
    failed = 0
    link_only = 0
    try:
        for media in videos:
            media_id = int(media["id"])
            raw_post_id = int(media["raw_post_id"])
            path = str(TMP_DIR / f"{TMP_PREFIX}backfill_{raw_post_id}_{media_id}.mp4")
            jlog(
                "video_start",
                media_id=media_id,
                raw_post_id=raw_post_id,
                url=media.get("original_url"),
                duration_sec=media.get("duration_sec"),
            )
            try:
                info = await worker.download_video(str(media.get("original_url") or ""), path)
                if not info:
                    await worker.mark_media_failed_attempt(media_id, "video download failed")
                    failed += 1
                    jlog("video_failed", media_id=media_id, raw_post_id=raw_post_id, error="video download failed")
                    continue
                if info.get("error"):
                    if info.get("permanent"):
                        await worker.mark_media_link_only(media_id, str(info["error"]))
                        link_only += 1
                    else:
                        await worker.mark_media_failed_attempt(media_id, str(info["error"]))
                        failed += 1
                    jlog("video_failed", media_id=media_id, raw_post_id=raw_post_id, error=info.get("error"))
                    continue
                await send_video_to_storage(worker, media, path)
                ok += 1
                jlog("video_uploaded", media_id=media_id, raw_post_id=raw_post_id, size_bytes=info.get("size_bytes"))
                await asyncio.sleep(worker.media_upload_delay_sec)
            except Exception as exc:
                await worker.mark_media_failed_attempt(media_id, str(exc))
                failed += 1
                jlog("video_failed", media_id=media_id, raw_post_id=raw_post_id, error=str(exc))
            finally:
                Path(path).unlink(missing_ok=True)
    finally:
        await worker.close()
        if worker.pool:
            await worker.pool.close()
    jlog("done", ok=ok, failed=failed, link_only=link_only, total=len(videos))


if __name__ == "__main__":
    asyncio.run(main())