"""scrape_pipeline.py — Avito full orchestrator (Stage 2e).

Координирует 5 шагов одного pipeline run:
  1. SEARCH   — AvitoScraper().fetch_around(lat, lon, radius_m)
  2. SAVE     — save_listings(db, lots) → (inserted, updated)
  3. GROUP    — dedupe house_url из lots → unique set
  4. ENRICH_HOUSES — fetch_house_catalog + save_house_catalog_enrichment per unique house
  5. ENRICH_DETAIL — top-N listings (detail_enriched_at IS NULL) → fetch_detail + save

Graceful degradation на каждом step: exception в одной house/listing
не валит весь pipeline.

IMV ОТСУТСТВУЕТ — он on-demand (Stage 3 estimator integration), не cron.
"""

from __future__ import annotations

import logging
from dataclasses import dataclass, field
from urllib.parse import urlparse

from sqlalchemy import text
from sqlalchemy.orm import Session

from app.services.scrapers.avito import AvitoScraper
from app.services.scrapers.avito_detail import fetch_detail, save_detail_enrichment
from app.services.scrapers.avito_houses import fetch_house_catalog, save_house_catalog_enrichment
from app.services.scrapers.base import ScrapedLot, save_listings

logger = logging.getLogger(__name__)


# ── Result dataclasses ──────────────────────────────────────────────────────


@dataclass
class PipelineCounters:
    """Counters одного pipeline run для логов/админки."""

    lots_fetched: int = 0
    lots_inserted: int = 0
    lots_updated: int = 0
    unique_houses: int = 0
    houses_enriched: int = 0
    houses_failed: int = 0
    detail_attempted: int = 0
    detail_enriched: int = 0
    detail_failed: int = 0
    errors: list[str] = field(default_factory=list)


@dataclass
class PipelineResult:
    """Полный результат full Avito pipeline."""

    anchor_lat: float
    anchor_lon: float
    radius_m: int
    counters: PipelineCounters
    enrich_houses: bool
    enrich_detail_top_n: int


# ── Main orchestrator ───────────────────────────────────────────────────────


async def run_avito_pipeline(
    db: Session,
    lat: float,
    lon: float,
    radius_m: int = 1500,
    *,
    enrich_houses: bool = True,
    enrich_detail_top_n: int = 10,
) -> PipelineResult:
    """Full Avito search → houses → detail enrichment pipeline.

    Steps:
      1. SEARCH: AvitoScraper().fetch_around(lat, lon, radius_m) → list[ScrapedLot]
      2. SAVE: save_listings(db, lots) → (inserted, updated)
      3. GROUP: dedupe house_url из новых lots → unique house path set
      4. ENRICH_HOUSES (если enrich_houses=True): для каждого unique house path
         → fetch_house_catalog + save_house_catalog_enrichment (try/except per house)
      5. ENRICH_DETAIL (если enrich_detail_top_n > 0): select top-N priority listings
         (приоритет — detail_enriched_at IS NULL + price > 0)
         → fetch_detail + save_detail_enrichment (try/except per listing)
      6. Return PipelineResult с counters

    Graceful degradation на каждом step — exception на одной house/listing
    не должна провалить весь pipeline.
    """
    counters = PipelineCounters()
    lots: list[ScrapedLot] = []

    # ── Step 1: search ──────────────────────────────────────────────────────
    async with AvitoScraper() as scraper:
        try:
            lots = await scraper.fetch_around(lat, lon, radius_m)
            counters.lots_fetched = len(lots)
            logger.info(
                "pipeline:search anchor=(%.4f,%.4f) r=%dm fetched=%d",
                lat,
                lon,
                radius_m,
                len(lots),
            )
        except Exception as e:
            logger.exception("pipeline:search failed")
            counters.errors.append(f"search: {e}")
            return PipelineResult(lat, lon, radius_m, counters, enrich_houses, enrich_detail_top_n)

    # ── Step 2: save listings ───────────────────────────────────────────────
    if lots:
        try:
            counters.lots_inserted, counters.lots_updated = save_listings(db, lots)
        except Exception as e:
            logger.exception("pipeline:save_listings failed")
            counters.errors.append(f"save_listings: {e}")

    # ── Step 3: group by house ──────────────────────────────────────────────
    # Dedupe house path (без host) для consistency; fetch_house_catalog принимает path
    unique_house_paths: set[str] = set()
    for lot in lots:
        if lot.house_url:
            try:
                parsed = urlparse(lot.house_url)
                path = parsed.path if parsed.path else lot.house_url
                unique_house_paths.add(path)
            except Exception:
                continue

    counters.unique_houses = len(unique_house_paths)
    logger.info("pipeline:group_by_house unique=%d", counters.unique_houses)

    # ── Step 4: enrich houses ───────────────────────────────────────────────
    if enrich_houses and unique_house_paths:
        for house_path in unique_house_paths:
            try:
                enrichment = await fetch_house_catalog(house_path)
                save_house_catalog_enrichment(db, enrichment)
                counters.houses_enriched += 1
            except Exception as e:
                logger.warning(
                    "pipeline:house_enrich failed for %s: %s", house_path, e
                )
                counters.houses_failed += 1
                counters.errors.append(f"house {house_path}: {e}")

    # ── Step 5: enrich detail для top-N priority listings ──────────────────
    if enrich_detail_top_n > 0:
        # Priority: листинги ещё не enriched (detail_enriched_at IS NULL)
        # в радиусе 2× от anchor ИЛИ только что scraped (последние 2 часа).
        # OR обёрнут в скобки — приоритет AND выше OR.
        priority_rows = db.execute(
            text("""
                SELECT source_url
                FROM listings
                WHERE source = 'avito'
                  AND source_url IS NOT NULL
                  AND (
                    (
                      detail_enriched_at IS NULL
                      AND price_rub > 0
                      AND ST_DWithin(
                        geom::geography,
                        ST_MakePoint(:lon, :lat)::geography,
                        :radius
                      )
                    )
                    OR (
                      detail_enriched_at IS NULL
                      AND scraped_at > NOW() - INTERVAL '2 hours'
                    )
                  )
                ORDER BY scraped_at DESC NULLS LAST
                LIMIT :limit
            """),
            {
                "lat": lat,
                "lon": lon,
                "radius": radius_m * 2,
                "limit": enrich_detail_top_n,
            },
        ).mappings().all()

        for row in priority_rows:
            source_url: str = row["source_url"]
            counters.detail_attempted += 1
            try:
                # fetch_detail принимает absolute URL или relative path
                item_url = (
                    urlparse(source_url).path
                    if source_url.startswith("http")
                    else source_url
                )
                enrichment_detail = await fetch_detail(item_url)
                if save_detail_enrichment(db, enrichment_detail):
                    counters.detail_enriched += 1
            except Exception as e:
                logger.warning(
                    "pipeline:detail_enrich failed for %s: %s", source_url, e
                )
                counters.detail_failed += 1
                counters.errors.append(f"detail {source_url}: {e}")

    logger.info(
        "pipeline:done anchor=(%.4f,%.4f) lots=%d (ins=%d/upd=%d) "
        "houses=%d/%d detail=%d/%d errors=%d",
        lat,
        lon,
        counters.lots_fetched,
        counters.lots_inserted,
        counters.lots_updated,
        counters.houses_enriched,
        counters.unique_houses,
        counters.detail_enriched,
        counters.detail_attempted,
        len(counters.errors),
    )

    return PipelineResult(lat, lon, radius_m, counters, enrich_houses, enrich_detail_top_n)


# ── Public re-exports ───────────────────────────────────────────────────────
__all__ = [
    "PipelineCounters",
    "PipelineResult",
    "run_avito_pipeline",
]