"""Scheduled task: backfill listings.address for EKB yandex listings with street-only addresses.

Pilot scope: Екатеринбург only (region_code=66, city hardcoded).
Yandex SERP cards include only the street name (e.g. «улица Горького»); the offer detail
page <title> contains the full address including house number:
  «Продажа квартиры — Екатеринбург, улица Горького, 36 — id 7654321 на Яндекс.Недвижимости»

This task selects active listings that match the predicate (source='yandex', region_code=66,
address IS NOT NULL, address has no house number, source_url IS NOT NULL), fetches each
detail page via curl_cffi(chrome120), extracts the full address from the <title>, and
UPDATE listings.address ONLY when the extracted value differs from the current one.

Wired into the in-app scheduler as source='yandex_address_backfill'. Triggered nightly via
the scrape_schedules seed (migration 091). Manual trigger also available via POST
/api/v1/admin/scrape/yandex-address-backfill.

Delegates actual HTTP + DB work to app.services.yandex_address_backfill.backfill_yandex_addresses
(the proven service module that already implements RE_TITLE_ADDRESS, _extract_address_from_title,
and _eligible_listings).
"""

from __future__ import annotations

import logging
from dataclasses import dataclass, field

from sqlalchemy.orm import Session

from app.services import scrape_runs as runs_mod
from app.services.yandex_address_backfill import (
    YandexAddressBackfillResult,
    backfill_yandex_addresses,
)

logger = logging.getLogger(__name__)

__all__ = [
    "YandexAddressBackfillTaskResult",
    "run_yandex_address_backfill",
]


@dataclass
class YandexAddressBackfillTaskResult:
    """Result counters from a scheduled backfill run."""

    checked: int = 0
    saved: int = 0
    skipped: int = 0
    errors: int = 0
    duration_sec: float = field(default=0.0)


async def run_yandex_address_backfill(
    db: Session,
    *,
    run_id: int,
    params: dict,
) -> YandexAddressBackfillTaskResult:
    """Execute Yandex address backfill with run lifecycle management.

    Wraps backfill_yandex_addresses(), emitting heartbeat before the batch call
    and marking the scrape_run as done/failed on completion.

    Params (from default_params jsonb in scrape_schedules):
        batch_size: int — max listings to process (default 200).
        request_delay_sec: float — seconds between requests (default 3.0).
    """
    batch_size = int(params.get("batch_size", 200))
    request_delay_sec = float(params.get("request_delay_sec", 3.0))

    counters: dict[str, int] = {
        "checked": 0,
        "saved": 0,
        "skipped": 0,
        "errors": 0,
    }

    try:
        runs_mod.update_heartbeat(db, run_id, counters)

        result: YandexAddressBackfillResult = await backfill_yandex_addresses(
            db,
            limit=batch_size,
            request_delay_sec=request_delay_sec,
        )

        counters = {
            "checked": result.checked,
            "saved": result.saved,
            "skipped": result.skipped,
            "errors": result.errors,
            "duration_sec": int(result.duration_sec),
        }
        runs_mod.mark_done(db, run_id, counters)
        logger.info(
            "scheduler: yandex_address_backfill run_id=%d done — "
            "checked=%d saved=%d skipped=%d errors=%d %.1fs",
            run_id,
            result.checked,
            result.saved,
            result.skipped,
            result.errors,
            result.duration_sec,
        )
        return YandexAddressBackfillTaskResult(
            checked=result.checked,
            saved=result.saved,
            skipped=result.skipped,
            errors=result.errors,
            duration_sec=result.duration_sec,
        )
    except Exception as exc:
        logger.exception("scheduler: yandex_address_backfill run_id=%d failed", run_id)
        runs_mod.mark_failed(db, run_id, str(exc)[:1000], counters)
        raise