#######################################################################
# Copyright (C) 2017 Shangtong Zhang(zhangshangtong.cpp@gmail.com)    #
# Permission given to modify the code as long as you keep this        #
# declaration at the top                                              #
#######################################################################

from .config import *
import torch
import os

def select_device(gpu_id):
    # if torch.cuda.is_available() and gpu_id >= 0:
    if gpu_id >= 0:
        Config.DEVICE = torch.device('cuda:%d' % (gpu_id))
    else:
        Config.DEVICE = torch.device('cpu')

def tensor(x):
    if isinstance(x, torch.Tensor):
        return x
    x = torch.tensor(x, device=Config.DEVICE, dtype=torch.float32)
    return x

def range_tensor(end):
    return torch.arange(end).long().to(Config.DEVICE)

def to_np(t):
    return t.cpu().detach().numpy()

def random_seed():
    np.random.seed()
    torch.manual_seed(np.random.randint(int(1e6)))

def set_one_thread():
    os.environ['OMP_NUM_THREADS'] = '1'
    os.environ['MKL_NUM_THREADS'] = '1'
    torch.set_num_threads(1)

def huber(x, k=1.0):
    return torch.where(x.abs() < k, 0.5 * x.pow(2), k * (x.abs() - 0.5 * k))

def epsilon_greedy(epsilon, x):
    if len(x.shape) == 1:
        return np.random.randint(len(x)) if np.random.rand() < epsilon else np.argmax(x)
    elif len(x.shape) == 2:
        random_actions = np.random.randint(x.shape[1])
        greedy_actions = np.argmax(x, axis=-1)
        dice = np.random.rand(x.shape[0])
        return np.where(dice < epsilon, random_actions, greedy_actions)

def sync_grad(target_network, src_network):
    for param, src_param in zip(target_network.parameters(), src_network.parameters()):
        param._grad = src_param.grad.clone()

@@ -1442,16 +1442,33 @@
 shape%5B1%5D
+, size=x.shape%5B0%5D
 )%0A      

Fix a bug for epsilon greedy policy with multiple workers