"""
Main function to control the simulator flow by selecting which postprocess function to run.

Users should fill in the "post_type" field in the input JSON with the postprocess
function that they wish to run. The value in the field should be in a format similar to a Python
import. For example, if your function is called "my_func" in the Python file "my_file", you should
put "my_file.my_func" in the "post_type" field in the JSON. The function should be in your app
folder: app/user_app/my_file.

The postprocess function should return anything that the user wishes to use.
"""
import importlib
import sys
import traceback

def postprocess_main(config, pre_data, inf_results):
    """Main function that calls the appropriate postprocess function.

    Arguments:
        config: TestConfig class that holds the user's input config and options
        pre_data: Dictionary of values passed from preprocess function
        inf_results: NumPy array resulting from inference
    """
    if config["post"]["post_bypass"]:
        print("Bypassing postprocess")
        return None

    try:
        # Get function in python import format (with dots)
        function = config["post"]["post_type"].replace("/", ".")
        module, function_name = function.rsplit(".", 1)
        postprocess = importlib.import_module(module)
        post_func = getattr(postprocess, function_name)
        results = post_func(config, pre_data, inf_results)
    except (ModuleNotFoundError, AttributeError) as error:
        traceback.print_exc()
        sys.exit(f"\n{error}. Please check {function} in your input JSON "
                 f"{config['flow']['input_json']}.")

    return results