from pathlib import Path
import os
import sys
import unittest

from ray.rllib.utils.test_utils import framework_iterator


def rollout_test(algo, env="CartPole-v0", test_episode_rollout=False):
    extra_config = ""
    if algo == "ARS":
        extra_config = ",\"train_batch_size\": 10, \"noise_size\": 250000"
    elif algo == "ES":
        extra_config = ",\"episodes_per_batch\": 1,\"train_batch_size\": 10, "\
                       "\"noise_size\": 250000"

    for fw in framework_iterator(frameworks=("tf", "torch")):
        fw_ = ", \"framework\": \"{}\"".format(fw)

        tmp_dir = os.popen("mktemp -d").read()[:-1]
        if not os.path.exists(tmp_dir):
            sys.exit(1)

        print("Saving results to {}".format(tmp_dir))

        rllib_dir = str(Path(__file__).parent.parent.absolute())
        print("RLlib dir = {}\nexists={}".format(rllib_dir,
                                                 os.path.exists(rllib_dir)))
        os.system("python {}/train.py --local-dir={} --run={} "
                  "--checkpoint-freq=1 ".format(rllib_dir, tmp_dir, algo) +
                  "--config='{" + "\"num_workers\": 1, \"num_gpus\": 0{}{}".
                  format(fw_, extra_config) +
                  ", \"timesteps_per_iteration\": 5,\"min_iter_time_s\": 0.1, "
                  "\"model\": {\"fcnet_hiddens\": [10]}"
                  "}' --stop='{\"training_iteration\": 1}'" +
                  " --env={}".format(env))

        checkpoint_path = os.popen("ls {}/default/*/checkpoint_1/"
                                   "checkpoint-1".format(tmp_dir)).read()[:-1]
        if not os.path.exists(checkpoint_path):
            sys.exit(1)
        print("Checkpoint path {} (exists)".format(checkpoint_path))

        # Test rolling out n steps.
        os.popen("python {}/rollout.py --run={} \"{}\" --steps=10 "
                 "--out=\"{}/rollouts_10steps.pkl\" --no-render".format(
                     rllib_dir, algo, checkpoint_path, tmp_dir)).read()
        if not os.path.exists(tmp_dir + "/rollouts_10steps.pkl"):
            sys.exit(1)
        print("rollout output (10 steps) exists!".format(checkpoint_path))

        # Test rolling out 1 episode.
        if test_episode_rollout:
            os.popen("python {}/rollout.py --run={} \"{}\" --episodes=1 "
                     "--out=\"{}/rollouts_1episode.pkl\" --no-render".format(
                         rllib_dir, algo, checkpoint_path, tmp_dir)).read()
            if not os.path.exists(tmp_dir + "/rollouts_1episode.pkl"):
                sys.exit(1)
            print("rollout output (1 ep) exists!".format(checkpoint_path))

        # Cleanup.
        os.popen("rm -rf \"{}\"".format(tmp_dir)).read()


class TestRollout(unittest.TestCase):
    def test_a3c(self):
        rollout_test("A3C")

    def test_ars(self):
        rollout_test("ARS")

    def test_ddpg(self):
        rollout_test("DDPG", env="Pendulum-v0")

    def test_dqn(self):
        rollout_test("DQN")

    def test_es(self):
        rollout_test("ES")

    def test_impala(self):
        rollout_test("IMPALA", env="CartPole-v0")

    def test_ppo(self):
        rollout_test("PPO", env="CartPole-v0", test_episode_rollout=True)

    def test_sac(self):
        rollout_test("SAC", env="Pendulum-v0")


if __name__ == "__main__":
    import pytest
    sys.exit(pytest.main(["-v", __file__]))