# Copyright (c) 2022 PaddlePaddle Authors. All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

import itertools
import os
import shutil
import subprocess
import sys
import tempfile
import unittest


class CommunicationTestDistBase(unittest.TestCase):
    def setUp(self, save_log_dir=None, num_of_devices=2, timeout=120):
        self._python_interp = sys.executable
        self._save_log_dir = save_log_dir
        self._log_dir = tempfile.TemporaryDirectory()
        self._num_of_devices = num_of_devices
        self._device_list = [str(i) for i in range(num_of_devices)]
        self._timeout = timeout
        self._seeds = [i + 10 for i in range(num_of_devices)]
        self._devices = ','.join(self._device_list)

    def run_test_case(self, script_file, user_defined_envs=None):
        runtime_envs = os.environ
        runtime_envs.update(user_defined_envs)
        runtime_envs["CUDA_VISIBLE_DEVICES"] = self._devices
        start_command = f"{self._python_interp} -u -m paddle.distributed.launch --log_dir {self._log_dir.name} --devices {self._devices} {script_file}"
        start_command_list = start_command.strip().split()

        try:
            self._launcher = subprocess.run(
                start_command_list,
                env=runtime_envs,
                timeout=self._timeout,
                check=True,
            )
        except subprocess.TimeoutExpired as err:
            raise TimeoutError(
                "Timeout while running command {}, try to set a longer period, {} is not enough.".format(
                    err.cmd, err.timeout
                )
            )
        except subprocess.CalledProcessError as err:
            raise RuntimeError(
                "Error occurs when running this test case. The return code of command {} is {}".format(
                    err.cmd, err.returncode
                )
            )

    def tearDown(self):
        if self._save_log_dir:
            temp_log_dir_name = os.path.basename(self._log_dir.name)
            dir_name = os.path.join(self._save_log_dir, temp_log_dir_name)
            if not os.path.isdir(dir_name):
                print("The running logs will copy to {}".format(dir_name))
                shutil.copytree(self._log_dir.name, dir_name)
            else:
                raise RuntimeError(
                    "Directory {} exists, failed to save log.".format(dir_name)
                )


def gen_product_envs_list(default_envs, changeable_envs):
    envs_list = []
    for values in itertools.product(*changeable_envs.values()):
        envs = dict(zip(changeable_envs.keys(), values))
        envs.update(default_envs)
        envs_list.append(envs)
    return envs_list
