helper.py

import bpy


ADDON_NAME = __package__.split(".")[0]


def get_addon_preferences() -> bpy.types.AddonPreferences:
    """Get the addon preferences.

    Returns:
        bpy.types.AddonPreferences: The addon preferences.
    """
    return bpy.context.preferences.addons[ADDON_NAME].preferences


def get_save_directory() -> str:
    """Get the path to the directory where the images are saved.

    Returns:
        str: The path to the directory where the images are saved.
    """
    from os import makedirs
    from os.path import exists
    from os.path import dirname
    from os.path import join

    preferences = get_addon_preferences()

    if not bpy.data.filepath:
        if preferences.is_use_another_directory and preferences.another_directory:
            return preferences.another_directory
        return bpy.app.tempdir

    if (
        preferences.is_use_another_directory
        and preferences.is_force_use_another_directory
        and preferences.another_directory
    ):
        return preferences.another_directory

    directory_path = dirname(bpy.data.filepath)
    if not preferences.is_use_subdirectory or not preferences.subdirectory_name:
        return directory_path
    subdirectory_path = join(directory_path, preferences.subdirectory_name)
    if not exists(subdirectory_path):
        makedirs(subdirectory_path)
    return subdirectory_path


def is_valid_filename(filename: str) -> bool:
    """Check if the filename is valid.

    Args:
        filename (str): a string representing the file name.

    Returns:
        bool: True if the filename is valid, False otherwise.
    """

    def is_general_valid_filename(filename: str) -> bool:
        """Check if the filename is valid.

        Args:
            filename (str): a string representing the file name.

        Returns:
            bool: True if the filename is valid, False otherwise.
        """
        if not filename:
            return False
        if len(filename) > 255:
            return False
        if filename in (".", ".."):
            return False
        return True

    def is_windows_valid_filename(filename: str) -> bool:
        """Check if the filename is valid on Windows.

        Args:
            filename (str): a string representing a filename.

        Returns:
            bool: True if the filename is valid on Windows, False otherwise.
        """
        # Check if the filename does not end with a dot or a space
        if filename[-1] in (".", " "):
            return False
        # Check if the filename is a reserved name
        windows_reserved_filenames = (
            "CON",
            "PRN",
            "AUX",
            "NUL",
            "COM1",
            "COM2",
            "COM3",
            "COM4",
            "COM5",
            "COM6",
            "COM7",
            "COM8",
            "COM9",
            "LPT1",
            "LPT2",
            "LPT3",
            "LPT4",
            "LPT5",
            "LPT6",
            "LPT7",
            "LPT8",
            "LPT9",
        )
        if filename.upper() in windows_reserved_filenames:
            return False
        # Check if the filename contains any invalid characters
        windows_invalid_characters = ("/", "\\", ":", "*", "?", '"', "<", ">", "|")
        for character in windows_invalid_characters:
            if character in filename:
                return False
        # Check if the filename contains any unprintable characters
        for index in range(31):
            if chr(index) in filename:
                return False
        return True

    def is_linux_valid_filename(filename: str) -> bool:
        """Check if the filename is valid on Linux.

        Args:
            filename (str): a string representing a filename.

        Returns:
            bool: True if the filename is valid on Linux, False otherwise.
        """
        # The "\" character is valid in Linux but Blender does not support it
        invalid_characters = ["/", "\\"]
        for invalid_character in invalid_characters:
            if invalid_character in filename:
                return False
        return True

    def is_darwin_valid_filename(filename: str) -> bool:
        """Check if the filename is valid on macOS.

        Args:
            filename (str): a string representing a filename.

        Returns:
            bool: True if the filename is valid on macOS, False otherwise.
        """
        return is_linux_valid_filename(filename)

    import sys

    if not is_general_valid_filename(filename):
        return False
    if sys.platform == "win32":
        return is_windows_valid_filename(filename)
    elif sys.platform == "linux":
        return is_linux_valid_filename(filename)
    elif sys.platform == "darwin":
        return is_darwin_valid_filename(filename)
    return False