"""Backfill houses.cian_zhk_url for rows that have cian_internal_house_id but no URL.

Requires migration 071_houses_cian_zhk_url.sql to be applied first.

What it does:
    SELECT houses WHERE cian_internal_house_id IS NOT NULL AND cian_zhk_url IS NULL
    For each row: resolve https://cian.ru/zhk/<id>/ → follow redirect → store final URL.

Cian redirects the canonical /zhk/<id>/ path to the slug URL
(e.g. https://zhk-park-ekb-i.cian.ru/). We capture the final redirect destination.

Usage:
    cd tradein-mvp/backend
    DATABASE_URL=postgresql://... uv run python ../scripts/backfill_cian_zhk_url.py

Env vars:
    DATABASE_URL   required — psycopg v3 DSN
    DELAY_SEC      default 5.0 — seconds between requests (Cian rate limit)
    BATCH_LIMIT    default 500 — max houses to process per run (safety cap)

Idempotent — skips houses where cian_zhk_url IS NOT NULL. Safe to re-run.
"""
from __future__ import annotations

import asyncio
import logging
import os
import sys
import time

import psycopg

sys.path.insert(0, os.path.join(os.path.dirname(__file__), "..", "backend"))

from app.services.scrapers.cian_newbuilding import resolve_cian_zhk_url

logging.basicConfig(
    format="%(asctime)s [%(levelname)s] %(message)s",
    level=logging.INFO,
)
logger = logging.getLogger("backfill_cian_zhk_url")

DATABASE_URL = os.environ.get("DATABASE_URL", "")
DELAY_SEC = float(os.environ.get("DELAY_SEC", "5.0"))
BATCH_LIMIT = int(os.environ.get("BATCH_LIMIT", "500"))


async def main() -> None:
    if not DATABASE_URL:
        logger.error("DATABASE_URL env var not set")
        sys.exit(1)

    conn = await psycopg.AsyncConnection.connect(DATABASE_URL)

    async with conn:
        rows = await (
            await conn.execute(
                """
                SELECT id, cian_internal_house_id
                FROM houses
                WHERE cian_internal_house_id IS NOT NULL
                  AND cian_zhk_url IS NULL
                ORDER BY id
                LIMIT %(lim)s
                """,
                {"lim": BATCH_LIMIT},
            )
        ).fetchall()

    total = len(rows)
    logger.info(
        "Found %d houses with cian_internal_house_id and no cian_zhk_url (limit=%d)",
        total,
        BATCH_LIMIT,
    )
    if total == 0:
        logger.info("Nothing to backfill.")
        return

    succeeded = 0
    failed = 0
    t0 = time.time()

    conn = await psycopg.AsyncConnection.connect(DATABASE_URL)
    async with conn:
        for i, (house_id, cian_id) in enumerate(rows, start=1):
            url = await resolve_cian_zhk_url(cian_id)
            if url:
                await conn.execute(
                    """
                    UPDATE houses
                    SET cian_zhk_url = %(url)s
                    WHERE id = %(hid)s
                      AND cian_zhk_url IS NULL
                    """,
                    {"url": url, "hid": house_id},
                )
                await conn.commit()
                succeeded += 1
                logger.info("[%d/%d] house_id=%s id=%s → %s", i, total, house_id, cian_id, url)
            else:
                failed += 1
                logger.warning(
                    "[%d/%d] house_id=%s id=%s — could not resolve URL",
                    i, total, house_id, cian_id,
                )

            if i < total:
                await asyncio.sleep(DELAY_SEC)

    elapsed = time.time() - t0
    logger.info(
        "Backfill complete: %d succeeded, %d failed, %.1fs total (%.1fs/req avg)",
        succeeded,
        failed,
        elapsed,
        elapsed / max(succeeded + failed, 1),
    )


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