import os
import importlib.util


_network_factory = {
}


def get_network(cfg):
    arch = cfg.network   # network: 'ro_34'
    heads = cfg.heads    # heads: {'ct_hm': 9, 'wh': 2}
    head_conv = cfg.head_conv
    num_layers = int(arch[arch.find('_') + 1:]) if '_' in arch else 0
    arch = arch[:arch.find('_')] if '_' in arch else arch
    get_model = _network_factory[arch]
    network = get_model(num_layers, heads, head_conv)
    return network


def make_network(cfg):
    module = '.'.join(['lib.networks', cfg.task])  # task: 'snake'
    path = os.path.join('lib/networks', cfg.task, '__init__.py')
    print("网络路径：", path)
    print("模型ID:", cfg.task)
    print("model:", cfg.model)
    
    # 使用importlib替代已弃用的imp模块
    spec = importlib.util.spec_from_file_location(module, path)
    module_obj = importlib.util.module_from_spec(spec)
    spec.loader.exec_module(module_obj)
    
    return module_obj.get_network(cfg)
    # 注意！！！这里的 get_network() 函数不是上面定义的的那个，而是动态导入进来的模块的函数
    # 此处的 get_network() 函数来自lib/networks/snake 文件