import yaml
from src import conv_onet


method_dict = {
    'conv_onet': conv_onet
}


def load_config(path, default_path=None):
    """
    Loads config file.

    Args:
        path (str): path to config file.
        default_path (str, optional): whether to use default path. Defaults to None.

    Returns:
        cfg (dict): config dict.

    """
    # load configuration from file itself
    with open(path, 'r') as f:
        cfg_special = yaml.full_load(f)

    # check if we should inherit from a config
    inherit_from = cfg_special.get('inherit_from')

    # if yes, load this config first as default
    # if no, use the default_path
    if inherit_from is not None:
        cfg = load_config(inherit_from, default_path)
    elif default_path is not None:
        with open(default_path, 'r') as f:
            cfg = yaml.full_load(f)
    else:
        cfg = dict()

    # include main configuration
    update_recursive(cfg, cfg_special)

    return cfg


def update_recursive(dict1, dict2):
    """
    Update two config dictionaries recursively.

    Args:
        dict1 (dict): first dictionary to be updated.
        dict2 (dict): second dictionary which entries should be used.
    """
    for k, v in dict2.items():
        if k not in dict1:
            dict1[k] = dict()
        if isinstance(v, dict):
            update_recursive(dict1[k], v)
        else:
            dict1[k] = v


# Models
def get_model(cfg, nice=True):
    """
    Returns the model instance.

    Args:
        cfg (dict): config dictionary.
        nice (bool, optional): if use NICE-SLAM. Defaults to True.

    Returns:
       model (nn.module): network model.
    """

    method = 'conv_onet'
    model = method_dict[method].config.get_model(
        cfg,  nice=nice)

    return model