import logging
import os
import sys
from logging.handlers import RotatingFileHandler
from pathlib import Path


BASE_DIR = Path(__file__).resolve().parent
DEFAULT_LOG_DIR = BASE_DIR / "logs"
DEFAULT_LOG_FILE_NAME = "gmv_sync.log"
LOGGER_NAME = "gmv_analytics"
LOG_FORMAT = "[%(asctime)s] %(message)s"
DATE_FORMAT = "%Y-%m-%d %H:%M:%S"

_IS_CONFIGURED = False


def _build_handlers() -> list[logging.Handler]:
    log_dir = Path(os.getenv("LOG_DIR", str(DEFAULT_LOG_DIR)))
    log_file_name = os.getenv("LOG_FILE_NAME", DEFAULT_LOG_FILE_NAME)
    log_file_path = log_dir / log_file_name
    log_dir.mkdir(parents=True, exist_ok=True)

    formatter = logging.Formatter(LOG_FORMAT, datefmt=DATE_FORMAT)

    console_handler = logging.StreamHandler(sys.stdout)
    console_handler.setFormatter(formatter)

    file_handler = RotatingFileHandler(
        log_file_path,
        maxBytes=int(os.getenv("LOG_MAX_BYTES", str(10 * 1024 * 1024))),
        backupCount=int(os.getenv("LOG_BACKUP_COUNT", "7")),
        encoding="utf-8",
    )
    file_handler.setFormatter(formatter)
    return [console_handler, file_handler]


def setup_logging(force: bool = False) -> logging.Logger:
    global _IS_CONFIGURED

    logger = logging.getLogger(LOGGER_NAME)
    if _IS_CONFIGURED and not force:
        return logger

    level_name = os.getenv("LOG_LEVEL", "INFO").strip().upper()
    level = getattr(logging, level_name, logging.INFO)
    handlers = _build_handlers()

    if force:
        for handler in list(logger.handlers):
            logger.removeHandler(handler)
            handler.close()

    logger.setLevel(level)
    logger.propagate = False
    for handler in handlers:
        logger.addHandler(handler)

    _IS_CONFIGURED = True
    return logger


def get_logger() -> logging.Logger:
    return setup_logging()