"""
===============================================================================
FILE: services/scud_etl/otchet_generator.py
ROLE: Генератор Детального Отчета за прошлые смены (строго по итоговому Y-снапшоту).
===============================================================================
"""

import os
import logging
from typing import Dict, Any, Optional
import pandas as pd

from config import DATE_YESTERDAY
from core.database import load_scud_from_db_by_snapshot
from services.scud_etl.pipeline import load_1c_files_for_date
from services.scud_etl.merger import merge_scud_and_1c
from services.excel_exporter import generate_detailed_excel, get_dated_reports_dir, format_date_ru

logger = logging.getLogger("OTCHET_GENERATOR")


def generate_otchet_service(
    target_date: Optional[str] = None, 
    snapshot_id: Optional[str] = None
) -> Dict[str, Any]:
    """
    Формирует детальный отчет за прошедшую смену:
    - target_date: дата отчета (по умолчанию вчерашний рабочий день).
    - snapshot_id: опциональный ID (по умолчанию выбирается итоговый вечерний срез Y).
    """
    date_clean = str(target_date or DATE_YESTERDAY).replace('_', '.')

    df_scud = load_scud_from_db_by_snapshot(date_clean, snapshot_param=snapshot_id)
    if df_scud is None or df_scud.empty:
        return {
            "status": "error",
            "message": f"Итоговый срез СКУД (Y) за {date_clean} не найден в базе данных."
        }

    df_staff, df_abs = load_1c_files_for_date(date_clean)
    df_merged = merge_scud_and_1c(df_scud, df_staff, df_abs)

    filename = f"{format_date_ru(date_clean)} отчет.xlsx"
    generate_detailed_excel(df_merged, date_str=date_clean, filename=filename)

    target_dir = get_dated_reports_dir(date_clean)
    full_filepath = os.path.join(target_dir, filename)

    return {
        "status": "success",
        "report_type": "OTCHET",
        "date": date_clean,
        "snapshot_id": snapshot_id or "AUTO_Y_FINAL",
        "filename": filename,
        "filepath": full_filepath,
        "download_url": f"/api/v1/files/download/reports/{os.path.basename(full_filepath)}",
        "total_rows": len(df_merged),
        "message": f"Детальный отчет за {date_clean} успешно сформирован."
    }