def analyze_files(dir):
    def check_dir(dir):
        try:
            for filename in os.listdir(dir):
                path_to_file = os.path.join(dir, filename)
                if os.path.isfile(path_to_file):
                    check_file(path_to_file)
                elif os.path.isdir(path_to_file):
                    check_dir(path_to_file)
        except PermissionError:
            print("{}: Permission denied".format(dir))

    def check_file(path_to_file):
        try:
            file = pefile.PE(path_to_file, fast_load=True)
            file.parse_data_directories(
                directories=[pefile.DIRECTORY_ENTRY['IMAGE_DIRECTORY_ENTRY_IMPORT']])
        except Exception:
            return

        first_found = True
        if hasattr(file, "DIRECTORY_ENTRY_IMPORT"):
            for library in file.DIRECTORY_ENTRY_IMPORT:
                try:
                    library_name = library.dll.decode().lower()
                except AttributeError:
                    continue
                if library_name in restricted_libraries:
                    suspicious_functions = []
                    for function in library.imports:
                        try:
                            function_name = function.name.decode()
                        except AttributeError:
                            continue
                        if function_name in restricted_libraries[library_name]:
                            suspicious_functions.append(function_name)
                    if suspicious_functions:
                        print("Suspicious file {}\nFile using network library: {}\n"
                              "Found following suspicious functions: {}".format(path_to_file, library_name,
                                                                                ', '.join(
                                                                                    suspicious_functions)))
                        first_found = False
                        break
        if not first_found:
            print()

    restricted_libraries = get_libraries_list()

    import os
    import pefile
    from timeit import default_timer
    start = default_timer()
    check_dir(dir)
    print("Total time: {}".format(default_timer() - start))


def get_libraries_list():
    with open("list_of_network_libraries.json", 'r') as file:
        import json
        return json.load(file)


if __name__ == "__main__":
    # analyze_files(input("Input directory to analyze: "))
    # analyze_files('Test_dir')
    analyze_files('C:\Windows\System32')