from pathlib import Path
import logging
from logging.handlers import RotatingFileHandler
import tempfile

from . import config


def _ensure_dir(p: Path) -> Path:
    p.mkdir(parents=True, exist_ok=True)
    return p


def get_logger(name: str = "launcher") -> logging.Logger:
    """Configura e restituisce un logger con file di log rotante.

    Primaria: %LOCALAPPDATA%\MyICR_Suite\launcher_cache\launcher.log
    Fallback: %TEMP%\MyICR_Suite_launcher\launcher.log
    """
    logger = logging.getLogger(name)

    # Evita duplicati
    if logger.handlers:
        return logger

    # Scegli percorso log con fallback robusto
    log_dir: Path
    try:
        log_dir = _ensure_dir(config.LOCAL_LAUNCHER_CACHE_DIR)
    except Exception:
        temp_base = Path(tempfile.gettempdir()) / "MyICR_Suite_launcher"
        log_dir = _ensure_dir(temp_base)

    log_path = log_dir / "launcher.log"

    handler = RotatingFileHandler(
        str(log_path), maxBytes=512 * 1024, backupCount=3, encoding="utf-8"
    )
    formatter = logging.Formatter(
        fmt="%(asctime)s | %(levelname)-8s | %(name)s:%(lineno)d - %(message)s",
        datefmt="%Y-%m-%d %H:%M:%S",
    )
    handler.setFormatter(formatter)

    logger.setLevel(logging.DEBUG)
    handler.setLevel(logging.DEBUG)
    logger.addHandler(handler)
    logger.propagate = False

    try:
        logger.info("Log inizializzato: %s", log_path)
    except Exception:
        pass

    return logger