Source code for SDF.config

"""Settings accessible to the user (via a config file)"""
import dataclasses
import json
import logging
import os
import platform

logger = logging.getLogger(__name__)


@dataclasses.dataclass
class SDFConfig:
    """Representation of the config file"""
    use_system_jpkfile: bool = False
    """if True: don't import jpkfile from SDF.extern"""
    use_system_oiffile: bool = False
    """if True: don't import offile from SDF.extern"""
    use_system_mfpfile: bool = False
    """if True: don't import mfpfile from SDF.extern"""
    use_system_tifffile: bool = False
    """if True: don't import tifffile from SDF.extern"""


def determine_config_dir() -> str:
    """Returns the absolute path of the sdf configuration directory. Creates the directory if it did not exist."""
    # determine config file path
    if platform.system() == "Linux":
        if "XDG_CONFIG_HOME" in os.environ.keys():
            config_dir = os.environ["XDG_CONFIG_HOME"] + "/sdf"
        else:
            config_dir = os.path.expanduser("~/.config/sdf")
    elif platform.system() == "Windows":
        config_dir = os.path.expandvars("%APPDATA%/sdf")
    elif platform.system() == "Darwin":  # MacOS
        config_dir = os.path.expanduser("~/Library/Preferences/sdf")
    else:
        config_dir = os.path.expanduser("~/.sdf")

    # generate config directory
    if not os.path.isdir(config_dir):
        os.makedirs(config_dir)

    return config_dir


def load_config(config_file) -> SDFConfig:
    """Load configuration from `config_file`"""
    # load config, generate file if necessary
    default_config = SDFConfig()
    default_config_dict = dataclasses.asdict(default_config)

    if not os.path.isfile(config_file):
        with open(config_file, 'w') as fp:
            json.dump(dataclasses.asdict(default_config), fp)
        return default_config
    else:
        with open(config_file, 'rt') as fh:
            config_dict: dict = json.load(fh)

        # check if entries are missing
        outdated = False
        for key in default_config_dict.keys() - config_dict.keys():
            config_dict[key] = default_config_dict[key]
            outdated = True

        if outdated:
            logger.info(f"Updating config file at {config_file}")
            with open(config_file, 'w') as fp:
                json.dump(config_dict, fp)

        # warn about unknown keys
        for key in config_dict.keys() - default_config_dict.keys():
            logger.info(f"Unknown key '{key}' found in config file {config_file}. Ignoring.")
            config_dict.pop(key)

        return SDFConfig(**config_dict)


CONFIG_DIR = determine_config_dir()
CONFIG = load_config(os.path.join(CONFIG_DIR, "config.json"))