from __future__ import annotations

import logging
import os
from pathlib import Path

# Logging paths used by the MCP package.
# The demo UI links directly to these files, so keep the layout stable.
BASE_CACHE = Path(os.environ.get("AILEEN3_CACHE_DIR", Path.home() / ".cache" / "aileen3"))
LOG_DIR = BASE_CACHE / "logs"
LOG_FILE = LOG_DIR / "aileen3-mcp.log"
PACKAGE_LOGGER_NAME = "aileen3_mcp"


def _resolve_level() -> int:
    """Resolve the log level from ``AILEEN3_LOGLEVEL`` or fall back to INFO."""
    level_name = os.environ.get("AILEEN3_LOGLEVEL", "").upper() or "INFO"
    level = getattr(logging, level_name, None)
    if isinstance(level, int):
        return level
    # Fallback for non-standard levels
    try:
        return int(level_name)
    except Exception:
        return logging.INFO


def configure_logging() -> Path:
    """Configure package logging without turning on DEBUG for third-party libs."""
    LOG_DIR.mkdir(parents=True, exist_ok=True)
    level = _resolve_level()

    pkg_logger = logging.getLogger(PACKAGE_LOGGER_NAME)
    pkg_logger.setLevel(level)
    pkg_logger.propagate = False  # keep third-party noise out of our handler

    existing = None
    for h in pkg_logger.handlers:
        if isinstance(h, logging.FileHandler) and Path(getattr(h, "baseFilename", "")) == LOG_FILE:
            existing = h
            break

    if existing:
        existing.setLevel(level)
    else:
        handler = logging.FileHandler(LOG_FILE, encoding="utf-8")
        handler.setLevel(level)
        handler.setFormatter(logging.Formatter("%(asctime)s [%(levelname)s] %(name)s: %(message)s"))
        pkg_logger.addHandler(handler)

    return LOG_FILE