meme_generator/dirs.py

# https://github.com/nonebot/plugin-localstore
"""
MIT License

Copyright (c) 2021 NoneBot

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
"""


import os
import sys
from pathlib import Path
from typing import Callable, Literal

from typing_extensions import ParamSpec

WINDOWS = sys.platform.startswith("win") or (sys.platform == "cli" and os.name == "nt")


def user_cache_dir(appname: str) -> Path:
    r"""
    Return full path to the user-specific cache dir for this application.
        "appname" is the name of application.
    Typical user cache directories are:
        macOS:      ~/Library/Caches/<AppName>
        Unix:       ~/.cache/<AppName> (XDG default)
        Windows:    C:\Users\<username>\AppData\Local\<AppName>\Cache
    On Windows the only suggestion in the MSDN docs is that local settings go
    in the `CSIDL_LOCAL_APPDATA` directory. This is identical to the
    non-roaming app data dir (the default returned by `user_data_dir`). Apps
    typically put cache data somewhere *under* the given dir here. Some
    examples:
        ...\Mozilla\Firefox\Profiles\<ProfileName>\Cache
        ...\Acme\SuperApp\Cache\1.0
    OPINION: This function appends "Cache" to the `CSIDL_LOCAL_APPDATA` value.
    """
    if WINDOWS:
        return _get_win_folder("CSIDL_LOCAL_APPDATA") / appname / "Cache"
    elif sys.platform == "darwin":
        return Path("~/Library/Caches").expanduser() / appname
    else:
        return Path(os.getenv("XDG_CACHE_HOME", "~/.cache")).expanduser() / appname


def user_data_dir(appname: str, roaming: bool = False) -> Path:
    r"""
    Return full path to the user-specific data dir for this application.
        "appname" is the name of application.
            If None, just the system directory is returned.
        "roaming" (boolean, default False) can be set True to use the Windows
            roaming appdata directory. That means that for users on a Windows
            network setup for roaming profiles, this user data will be
            sync'd on login. See
            <http://technet.microsoft.com/en-us/library/cc766489(WS.10).aspx>
            for a discussion of issues.
    Typical user data directories are:
        macOS:                  ~/Library/Application Support/<AppName>
        Unix:                   ~/.local/share/<AppName>    # or in
                                $XDG_DATA_HOME, if defined
        Win XP (not roaming):   C:\Documents and Settings\<username>\ ...
                                ...Application Data\<AppName>
        Win XP (roaming):       C:\Documents and Settings\<username>\Local ...
                                ...Settings\Application Data\<AppName>
        Win 7  (not roaming):   C:\Users\<username>\AppData\Local\<AppName>
        Win 7  (roaming):       C:\Users\<username>\AppData\Roaming\<AppName>
    For Unix, we follow the XDG spec and support $XDG_DATA_HOME.
    That means, by default "~/.local/share/<AppName>".
    """
    if WINDOWS:
        const = "CSIDL_APPDATA" if roaming else "CSIDL_LOCAL_APPDATA"
        return Path(_get_win_folder(const)) / appname
    elif sys.platform == "darwin":
        return Path("~/Library/Application Support/").expanduser() / appname
    else:
        return Path(os.getenv("XDG_DATA_HOME", "~/.local/share")).expanduser() / appname


def user_config_dir(appname: str, roaming: bool = True) -> Path:
    """Return full path to the user-specific config dir for this application.
        "appname" is the name of application.
            If None, just the system directory is returned.
        "roaming" (boolean, default True) can be set False to not use the
            Windows roaming appdata directory. That means that for users on a
            Windows network setup for roaming profiles, this user data will be
            sync'd on login. See
            <http://technet.microsoft.com/en-us/library/cc766489(WS.10).aspx>
            for a discussion of issues.
    Typical user data directories are:
        macOS:                  same as user_data_dir
        Unix:                   ~/.config/<AppName>
        Win *:                  same as user_data_dir
    For Unix, we follow the XDG spec and support $XDG_CONFIG_HOME.
    That means, by default "~/.config/<AppName>".
    """
    if WINDOWS:
        return user_data_dir(appname, roaming=roaming)
    elif sys.platform == "darwin":
        return user_data_dir(appname)
    else:
        return Path(os.getenv("XDG_CONFIG_HOME", "~/.config")).expanduser() / appname


# -- Windows support functions --
def _get_win_folder_from_registry(
    csidl_name: Literal["CSIDL_APPDATA", "CSIDL_COMMON_APPDATA", "CSIDL_LOCAL_APPDATA"]
) -> Path:
    """
    This is a fallback technique at best. I'm not sure if using the
    registry for this guarantees us the correct answer for all CSIDL_*
    names.
    """
    import winreg

    shell_folder_name = {
        "CSIDL_APPDATA": "AppData",
        "CSIDL_COMMON_APPDATA": "Common AppData",
        "CSIDL_LOCAL_APPDATA": "Local AppData",
    }[csidl_name]

    key = winreg.OpenKey(
        winreg.HKEY_CURRENT_USER,
        r"Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders",
    )
    directory, _type = winreg.QueryValueEx(key, shell_folder_name)
    return Path(directory)


def _get_win_folder_with_ctypes(
    csidl_name: Literal["CSIDL_APPDATA", "CSIDL_COMMON_APPDATA", "CSIDL_LOCAL_APPDATA"]
) -> Path:
    csidl_const = {
        "CSIDL_APPDATA": 26,
        "CSIDL_COMMON_APPDATA": 35,
        "CSIDL_LOCAL_APPDATA": 28,
    }[csidl_name]

    buf = ctypes.create_unicode_buffer(1024)
    ctypes.windll.shell32.SHGetFolderPathW(None, csidl_const, None, 0, buf)

    # Downgrade to short path name if have highbit chars. See
    # <http://bugs.activestate.com/show_bug.cgi?id=85099>.
    has_high_char = any(ord(c) > 255 for c in buf)
    if has_high_char:
        buf2 = ctypes.create_unicode_buffer(1024)
        if ctypes.windll.kernel32.GetShortPathNameW(buf.value, buf2, 1024):
            buf = buf2

    return Path(buf.value)


if WINDOWS:
    try:
        import ctypes

        _get_win_folder = _get_win_folder_with_ctypes
    except ImportError:
        _get_win_folder = _get_win_folder_from_registry


P = ParamSpec("P")

APP_NAME = "meme_generator"
BASE_CACHE_DIR = user_cache_dir(APP_NAME).resolve()
BASE_CONFIG_DIR = user_config_dir(APP_NAME).resolve()
BASE_DATA_DIR = user_data_dir(APP_NAME).resolve()


def _ensure_dir(path: Path) -> None:
    if not path.exists():
        path.mkdir(parents=True, exist_ok=True)
    elif not path.is_dir():
        raise RuntimeError(f"{path} is not a directory")


def _auto_create_dir(func: Callable[P, Path]) -> Callable[P, Path]:
    def wrapper(*args: P.args, **kwargs: P.kwargs) -> Path:
        path = func(*args, **kwargs)
        _ensure_dir(path)
        return path

    return wrapper


@_auto_create_dir
def get_cache_dir() -> Path:
    return BASE_CACHE_DIR


def get_cache_file(filename: str) -> Path:
    return get_cache_dir() / filename


@_auto_create_dir
def get_config_dir() -> Path:
    return BASE_CONFIG_DIR


def get_config_file(filename: str) -> Path:
    return get_config_dir() / filename


@_auto_create_dir
def get_data_dir() -> Path:
    return BASE_DATA_DIR


def get_data_file(filename: str) -> Path:
    return get_data_dir() / filename