def METHOD_NAME(app_dir, apk_file):
    """QUARK Analysis of APK files."""
    if not settings_enabled('QUARK_ENABLED'):
        return []
    try:
        import quark
    except ImportError:
        logger.error('Failed to import Quark')
        return []
    if not Path(apk_file).exists():
        logger.error('APK not found')
        return []
    quark_ver = quark.__version__
    from quark import config
    from quark.freshquark import download
    from quark.report import Report
    logger.info('Running Quark %s', quark_ver)
    json_report = {}
    try:
        # freshquark: update quark rules
        disable_print()
        download()
        enable_print()
        # default rules path
        rules_dir = Path(f'{config.HOME_DIR}quark-rules/rules')
        report = Report()
        # Analyze apk
        report.analysis(apk_file, rules_dir)
        # Generate Report
        json_report = report.get_report('json')
        # Clear all functools.lru_cache from quark
        report.quark.apkinfo.find_method.cache_clear()
        report.quark.apkinfo.upperfunc.cache_clear()
        report.quark.apkinfo.get_wrapper_smali.cache_clear()
    except Exception:
        logger.exception('Quark APK Analysis')
    return _convert_report(json_report, app_dir)