"""
이벤트 자동 생성기 — 분석 결과 → prediction_events INSERT.

매 분석 사이클마다 vessel_analysis_results를 스캔하여
룰 기반으로 Event 객체를 생성합니다.
dedup: 동일 mmsi + category + 윈도우 내 중복 방지.
"""
import hashlib
import logging
from datetime import datetime, timedelta, timezone
from typing import Optional

from psycopg2.extras import execute_values

from config import qualified_table, settings
from db.kcgdb import get_conn

logger = logging.getLogger(__name__)

EVENTS_TABLE = qualified_table('prediction_events')

# 카테고리별 dedup 윈도우 (분)
DEDUP_WINDOWS = {
    'EEZ_INTRUSION': 30,
    'DARK_VESSEL': 120,
    'FLEET_CLUSTER': 360,
    'ILLEGAL_TRANSSHIP': 60,
    'MMSI_TAMPERING': 30,
    'AIS_LOSS': 120,
    'SPEED_ANOMALY': 60,
    'ZONE_DEPARTURE': 120,
    'GEAR_ILLEGAL': 360,
    'AIS_RESUME': 60,
}

# 이벤트 생성 룰
RULES = [
    {
        'name': 'critical_risk',
        'condition': lambda r: r.get('risk_score', 0) >= 90,
        'level': 'CRITICAL',
        'category': 'EEZ_INTRUSION',
        'title_fn': lambda r: f"고위험 선박 탐지 (위험도 {r.get('risk_score', 0)})",
    },
    {
        'name': 'eez_violation',
        'condition': lambda r: r.get('zone_code', '') in ('NLL', 'SPECIAL_FISHING_1', 'SPECIAL_FISHING_2')
                     and r.get('risk_score', 0) >= 70,
        'level': 'CRITICAL',
        'category': 'EEZ_INTRUSION',
        'title_fn': lambda r: f"EEZ 침범 탐지 ({r.get('zone_code', '')})",
    },
    {
        'name': 'dark_vessel_long',
        'condition': lambda r: r.get('is_dark') and (r.get('gap_duration_min', 0) or 0) > 60,
        'level': 'HIGH',
        'category': 'DARK_VESSEL',
        'title_fn': lambda r: f"다크베셀 장기 소실 ({r.get('gap_duration_min', 0)}분)",
    },
    {
        'name': 'spoofing',
        'condition': lambda r: (r.get('spoofing_score', 0) or 0) > 0.7,
        'level': 'HIGH',
        'category': 'MMSI_TAMPERING',
        'title_fn': lambda r: f"GPS/MMSI 조작 의심 (점수 {r.get('spoofing_score', 0):.2f})",
    },
    {
        'name': 'transship',
        'condition': lambda r: r.get('transship_suspect'),
        'level': 'HIGH',
        'category': 'ILLEGAL_TRANSSHIP',
        'title_fn': lambda r: f"환적 의심 (상대: {r.get('transship_pair_mmsi', '미상')})",
    },
    {
        'name': 'fleet_cluster',
        'condition': lambda r: r.get('fleet_is_leader') and (r.get('fleet_cluster_id') is not None),
        'level': 'MEDIUM',
        'category': 'FLEET_CLUSTER',
        'title_fn': lambda r: f"선단 밀집 감지 (클러스터 {r.get('fleet_cluster_id')})",
    },
    {
        'name': 'high_risk',
        'condition': lambda r: r.get('risk_level') == 'HIGH' and r.get('risk_score', 0) >= 60,
        'level': 'MEDIUM',
        'category': 'ZONE_DEPARTURE',
        'title_fn': lambda r: f"위험 행동 패턴 (위험도 {r.get('risk_score', 0)})",
    },
]


def _make_dedup_key(mmsi: str, category: str) -> str:
    return f"{mmsi}:{category}"


def _make_event_uid(now: datetime, seq: int) -> str:
    date_str = now.strftime('%Y%m%d')
    return f"EVT-{date_str}-{seq:04d}"


def _get_next_seq(conn, date_str: str) -> int:
    cur = conn.cursor()
    cur.execute(
        f"SELECT COUNT(*) FROM {EVENTS_TABLE} WHERE event_uid LIKE %s",
        (f'EVT-{date_str}-%',)
    )
    return cur.fetchone()[0] + 1


def _check_dedup(conn, dedup_key: str, category: str, now: datetime) -> bool:
    """중복 이벤트 존재 여부 확인."""
    window_min = DEDUP_WINDOWS.get(category, 60)
    cutoff = now - timedelta(minutes=window_min)
    cur = conn.cursor()
    cur.execute(
        f"SELECT 1 FROM {EVENTS_TABLE} WHERE dedup_key = %s AND occurred_at > %s LIMIT 1",
        (dedup_key, cutoff)
    )
    return cur.fetchone() is not None


def run_event_generator(analysis_results: list[dict]) -> dict:
    """
    분석 결과 리스트를 스캔하여 이벤트 생성.

    Args:
        analysis_results: vessel_analysis_results 행 딕셔너리 리스트
            (mmsi, risk_score, zone_code, is_dark, gap_duration_min, spoofing_score, ...)

    Returns:
        { 'generated': int, 'skipped_dedup': int }
    """
    now = datetime.now(timezone.utc)
    generated = 0
    skipped_dedup = 0
    events_to_insert = []

    with get_conn() as conn:
        date_str = now.strftime('%Y%m%d')
        seq = _get_next_seq(conn, date_str)

        for result in analysis_results:
            mmsi = result.get('mmsi', '')
            if not mmsi:
                continue

            for rule in RULES:
                try:
                    if not rule['condition'](result):
                        continue
                except Exception:
                    continue

                category = rule['category']
                dedup_key = _make_dedup_key(mmsi, category)

                if _check_dedup(conn, dedup_key, category, now):
                    skipped_dedup += 1
                    continue

                event_uid = _make_event_uid(now, seq)
                seq += 1

                events_to_insert.append((
                    event_uid,
                    now,                                # occurred_at
                    rule['level'],
                    category,
                    rule['title_fn'](result),           # title
                    None,                               # detail
                    mmsi,
                    result.get('vessel_name'),
                    result.get('zone_code'),             # area_name (zone으로 대체)
                    result.get('zone_code'),
                    result.get('lat'),
                    result.get('lon'),
                    result.get('speed_kn'),
                    'VESSEL_ANALYSIS',                  # source_type
                    result.get('id'),                   # source_ref_id
                    result.get('confidence') or result.get('risk_score', 0) / 100.0,
                    'NEW',                              # status
                    dedup_key,
                ))
                generated += 1
                break  # 한 분석결과당 최고 우선순위 룰 1개만

        if events_to_insert:
            execute_values(
                conn.cursor(),
                f"""INSERT INTO {EVENTS_TABLE}
                    (event_uid, occurred_at, level, category, title, detail,
                     vessel_mmsi, vessel_name, area_name, zone_code, lat, lon, speed_kn,
                     source_type, source_ref_id, ai_confidence, status, dedup_key)
                    VALUES %s
                    ON CONFLICT (event_uid) DO NOTHING""",
                events_to_insert,
            )
            conn.commit()

    logger.info(f'event_generator: generated={generated}, skipped_dedup={skipped_dedup}')
    return {'generated': generated, 'skipped_dedup': skipped_dedup}