#!/usr/bin/env python3
"""
Utility functions for ParentZone Downloader

This module contains shared utility functions used across multiple modules.
"""


def sanitize_filename(filename: str) -> str:
    """
    Sanitize filename by removing invalid characters.

    Args:
        filename: The filename to sanitize

    Returns:
        Sanitized filename safe for filesystem use
    """
    # Remove or replace invalid characters
    invalid_chars = '<>:"/\\|?*'
    for char in invalid_chars:
        filename = filename.replace(char, "_")

    # Remove leading/trailing spaces and dots
    filename = filename.strip(". ")

    # Ensure filename is not empty
    if not filename:
        filename = "file"

    return filename


def get_extension_from_mime(mime_type: str) -> str:
    """
    Get file extension from MIME type.

    Args:
        mime_type: The MIME type string (e.g., 'image/jpeg')

    Returns:
        File extension including the dot (e.g., '.jpg')
    """
    mime_to_ext = {
        "image/jpeg": ".jpg",
        "image/jpg": ".jpg",
        "image/png": ".png",
        "image/gif": ".gif",
        "image/webp": ".webp",
        "image/bmp": ".bmp",
        "image/tiff": ".tiff",
        "image/svg+xml": ".svg",
    }
    return mime_to_ext.get(mime_type.lower(), ".jpg")