# Copyright (c) Microsoft Corporation.
# Licensed under the MIT license.

import glob
import json
import logging
import os
import random
import shutil
import sys
from collections import deque
from unittest import TestCase, main

from nni.algorithms.hpo.batch_tuner import BatchTuner
from nni.algorithms.hpo.evolution_tuner import EvolutionTuner
from nni.algorithms.hpo.gp_tuner import GPTuner
from nni.algorithms.hpo.gridsearch_tuner import GridSearchTuner
from nni.algorithms.hpo.hyperopt_tuner import HyperoptTuner
from nni.algorithms.hpo.metis_tuner import MetisTuner
from nni.algorithms.hpo.pbt_tuner import PBTTuner
from nni.algorithms.hpo.regularized_evolution_tuner import RegularizedEvolutionTuner
from nni.runtime.msg_dispatcher import _pack_parameter, MsgDispatcher

if sys.platform != 'win32':
    from nni.algorithms.hpo.smac_tuner import SMACTuner

from nni.tuner import Tuner

logging.basicConfig(level=logging.INFO)
logger = logging.getLogger('test_tuner')


class BuiltinTunersTestCase(TestCase):
    """
    Targeted at testing functions of built-in tuners, including
        - [ ] load_checkpoint
        - [ ] save_checkpoint
        - [X] update_search_space
        - [X] generate_multiple_parameters
        - [X] import_data
        - [ ] trial_end
        - [x] receive_trial_result
    """

    def setUp(self):
        self.test_round = 3
        self.params_each_round = 50
        self.exhaustive = False

    def send_trial_callback(self, param_queue):
        def receive(*args):
            param_queue.append(tuple(args))
        return receive

    def send_trial_result(self, tuner, parameter_id, parameters, metrics):
        tuner.receive_trial_result(parameter_id, parameters, metrics)
        tuner.trial_end(parameter_id, True)

    def search_space_test_one(self, tuner_factory, search_space, nas=False):
        # nas: whether the test checks classic nas tuner
        tuner = tuner_factory()
        self.assertIsInstance(tuner, Tuner)
        tuner.update_search_space(search_space)

        for i in range(self.test_round):
            queue = deque()
            parameters = tuner.generate_multiple_parameters(list(range(i * self.params_each_round,
                                                                       (i + 1) * self.params_each_round)),
                                                            st_callback=self.send_trial_callback(queue))
            logger.debug(parameters)
            check_range = lambda parameters, search_space: self.nas_check_range(parameters, search_space) \
                                                           if nas else self.check_range(parameters, search_space)
            check_range(parameters, search_space)
            for k in range(min(len(parameters), self.params_each_round)):
                self.send_trial_result(tuner, self.params_each_round * i + k, parameters[k], random.uniform(-100, 100))
            while queue:
                id_, params = queue.popleft()
                check_range([params], search_space)
                self.send_trial_result(tuner, id_, params, random.uniform(-100, 100))
            if not parameters and not self.exhaustive:
                raise ValueError("No parameters generated")

    def check_range(self, generated_params, search_space):
        EPS = 1E-6
        for param in generated_params:
            if self._testMethodName == "test_batch":
                param = {list(search_space.keys())[0]: param}
            for k, v in param.items():
                if k == "load_checkpoint_dir" or k == "save_checkpoint_dir":
                    self.assertIsInstance(v, str)
                    continue
                if k.startswith("_mutable_layer"):
                    _, block, layer, choice = k.split("/")
                    cand = search_space[block]["_value"][layer].get(choice)
                    # cand could be None, e.g., optional_inputs_chosen_state
                    if choice == "layer_choice":
                        self.assertIn(v, cand)
                    if choice == "optional_input_size":
                        if isinstance(cand, int):
                            self.assertEqual(v, cand)
                        else:
                            self.assertGreaterEqual(v, cand[0])
                            self.assertLessEqual(v, cand[1])
                    if choice == "optional_inputs":
                        pass  # ignore for now
                    continue
                item = search_space[k]
                if item["_type"] == "choice":
                    self.assertIn(v, item["_value"])
                if item["_type"] == "randint":
                    self.assertIsInstance(v, int)
                if item["_type"] == "uniform":
                    self.assertIsInstance(v, float)
                if item["_type"] in ("randint", "uniform", "quniform", "loguniform", "qloguniform"):
                    self.assertGreaterEqual(v, item["_value"][0])
                    self.assertLessEqual(v, item["_value"][1])
                if item["_type"].startswith("q"):
                    multiple = v / item["_value"][2]
                    print(k, v, multiple, item)
                    if item["_value"][0] + EPS < v < item["_value"][1] - EPS:
                        self.assertAlmostEqual(int(round(multiple)), multiple)
                if item["_type"] in ("qlognormal", "lognormal"):
                    self.assertGreaterEqual(v, 0)
                if item["_type"] == "mutable_layer":
                    for layer_name in item["_value"].keys():
                        self.assertIn(v[layer_name]["chosen_layer"], item["layer_choice"])

    def nas_check_range(self, generated_params, search_space):
        for params in generated_params:
            for k in params:
                v = params[k]
                items = search_space[k]
                if items['_type'] == 'layer_choice':
                    self.assertIn(v['_value'], items['_value'])
                elif items['_type'] == 'input_choice':
                    for choice in v['_value']:
                        self.assertIn(choice, items['_value']['candidates'])
                else:
                    raise KeyError

    def search_space_test_all(self, tuner_factory, supported_types=None, ignore_types=None, fail_types=None):
        # Three types: 1. supported; 2. ignore; 3. fail.
        # NOTE(yuge): ignore types
        # Supported types are listed in the table. They are meant to be supported and should be correct.
        # Other than those, all the rest are "unsupported", which are expected to produce ridiculous results
        # or throw some exceptions. However, there are certain types I can't check. For example, generate
        # "normal" using GP Tuner returns successfully and results are fine if we check the range (-inf to +inf),
        # but they make no sense: it's not a normal distribution. So they are ignored in tests for now.
        with open(os.path.join(os.path.dirname(__file__), "assets/search_space.json"), "r") as fp:
            search_space_all = json.load(fp)
        if supported_types is None:
            supported_types = ["choice", "randint", "uniform", "quniform", "loguniform", "qloguniform",
                               "normal", "qnormal", "lognormal", "qlognormal"]
        if fail_types is None:
            fail_types = []
        if ignore_types is None:
            ignore_types = []
        full_supported_search_space = dict()
        for single in search_space_all:
            space = search_space_all[single]
            if any(single.startswith(t) for t in ignore_types):
                continue
            expected_fail = not any(single.startswith(t) for t in supported_types) or \
                any(single.startswith(t) for t in fail_types) or \
                "fail" in single  # name contains fail (fail on all)
            single_search_space = {single: space}
            if not expected_fail:
                # supports this key
                self.search_space_test_one(tuner_factory, single_search_space)
                full_supported_search_space.update(single_search_space)
            else:
                # unsupported key
                with self.assertRaises(Exception, msg="Testing {}".format(single)) as cm:
                    self.search_space_test_one(tuner_factory, single_search_space)
                logger.info("%s %s %s", tuner_factory, single, cm.exception)
        if not any(t in self._testMethodName for t in ["batch", "grid_search"]):
            # grid search fails for too many combinations
            logger.info("Full supported search space: %s", full_supported_search_space)
            self.search_space_test_one(tuner_factory, full_supported_search_space)

    def nas_search_space_test_all(self, tuner_factory):
        # Since classic tuner should support only LayerChoice and InputChoice,
        # ignore type and fail type are dismissed here. 
        with open(os.path.join(os.path.dirname(__file__), "assets/classic_nas_search_space.json"), "r") as fp:
            search_space_all = json.load(fp)
        full_supported_search_space = dict()
        for single in search_space_all:
            space = search_space_all[single]
            single_search_space = {single: space}
            self.search_space_test_one(tuner_factory, single_search_space, nas=True)
            full_supported_search_space.update(single_search_space)
        logger.info("Full supported search space: %s", full_supported_search_space)
        self.search_space_test_one(tuner_factory, full_supported_search_space, nas=True)

    def import_data_test_for_pbt(self):
        """
        test1: import data with complete epoch
        test2: import data with incomplete epoch
        """
        search_space = {
            "choice_str": {
                "_type": "choice",
                "_value": ["cat", "dog", "elephant", "cow", "sheep", "panda"]
            }
        }
        all_checkpoint_dir = os.path.expanduser("~/nni/checkpoint/test/")
        population_size = 4
        # ===import data at the beginning===
        tuner = PBTTuner(
            all_checkpoint_dir=all_checkpoint_dir,
            population_size=population_size
        )
        self.assertIsInstance(tuner, Tuner)
        tuner.update_search_space(search_space)
        save_dirs = [os.path.join(all_checkpoint_dir, str(i), str(0)) for i in range(population_size)]
        # create save checkpoint directory
        for save_dir in save_dirs:
            os.makedirs(save_dir, exist_ok=True)
        # for simplicity, omit "load_checkpoint_dir"
        data = [{"parameter": {"choice_str": "cat", "save_checkpoint_dir": save_dirs[0]}, "value": 1.1},
                {"parameter": {"choice_str": "dog", "save_checkpoint_dir": save_dirs[1]}, "value": {"default": 1.2, "tmp": 2}},
                {"parameter": {"choice_str": "cat", "save_checkpoint_dir": save_dirs[2]}, "value": 11},
                {"parameter": {"choice_str": "cat", "save_checkpoint_dir": save_dirs[3]}, "value": 7}]
        epoch = tuner.import_data(data)
        self.assertEqual(epoch, 1)
        logger.info("Imported data successfully at the beginning")
        shutil.rmtree(all_checkpoint_dir)
        # ===import another data at the beginning, test the case when there is an incompleted epoch===
        tuner = PBTTuner(
            all_checkpoint_dir=all_checkpoint_dir,
            population_size=population_size
        )
        self.assertIsInstance(tuner, Tuner)
        tuner.update_search_space(search_space)
        for i in range(population_size - 1):
            save_dirs.append(os.path.join(all_checkpoint_dir, str(i), str(1)))
        for save_dir in save_dirs:
            os.makedirs(save_dir, exist_ok=True)
        data = [{"parameter": {"choice_str": "cat", "save_checkpoint_dir": save_dirs[0]}, "value": 1.1},
                {"parameter": {"choice_str": "dog", "save_checkpoint_dir": save_dirs[1]}, "value": {"default": 1.2, "tmp": 2}},
                {"parameter": {"choice_str": "cat", "save_checkpoint_dir": save_dirs[2]}, "value": 11},
                {"parameter": {"choice_str": "cat", "save_checkpoint_dir": save_dirs[3]}, "value": 7},
                {"parameter": {"choice_str": "cat", "save_checkpoint_dir": save_dirs[4]}, "value": 1.1},
                {"parameter": {"choice_str": "dog", "save_checkpoint_dir": save_dirs[5]}, "value": {"default": 1.2, "tmp": 2}},
                {"parameter": {"choice_str": "cat", "save_checkpoint_dir": save_dirs[6]}, "value": 11}]
        epoch = tuner.import_data(data)
        self.assertEqual(epoch, 1)
        logger.info("Imported data successfully at the beginning with incomplete epoch")
        shutil.rmtree(all_checkpoint_dir)

    def import_data_test(self, tuner_factory, stype="choice_str"):
        """
        import data at the beginning with number value and dict value
        import data in the middle also with number value and dict value, and duplicate data record
        generate parameters after data import

        Parameters
        ----------
        tuner_factory : lambda
            a lambda for instantiate a tuner
        stype : str
            the value type of hp choice, support "choice_str" and "choice_num"
        """
        if stype == "choice_str":
            search_space = {
                "choice_str": {
                    "_type": "choice",
                    "_value": ["cat", "dog", "elephant", "cow", "sheep", "panda"]
                }
            }
        elif stype == "choice_num":
            search_space = {
                "choice_num": {
                    "_type": "choice",
                    "_value": [10, 20, 30, 40, 50, 60]
                }
            }
        else:
            raise RuntimeError("Unexpected stype")
        tuner = tuner_factory()
        self.assertIsInstance(tuner, Tuner)
        tuner.update_search_space(search_space)
        # import data at the beginning
        if stype == "choice_str":
            data = [{"parameter": {"choice_str": "cat"}, "value": 1.1},
                    {"parameter": {"choice_str": "dog"}, "value": {"default": 1.2, "tmp": 2}}]
        else:
            data = [{"parameter": {"choice_num": 20}, "value": 1.1},
                    {"parameter": {"choice_num": 60}, "value": {"default": 1.2, "tmp": 2}}]
        tuner.import_data(data)
        logger.info("Imported data successfully at the beginning")
        # generate parameters
        parameters = tuner.generate_multiple_parameters(list(range(3)))
        for i in range(3):
            tuner.receive_trial_result(i, parameters[i], random.uniform(-100, 100))
        # import data in the middle
        if stype == "choice_str":
            data = [{"parameter": {"choice_str": "cat"}, "value": 1.1},
                    {"parameter": {"choice_str": "dog"}, "value": {"default": 1.2, "tmp": 2}},
                    {"parameter": {"choice_str": "cow"}, "value": 1.3}]
        else:
            data = [{"parameter": {"choice_num": 20}, "value": 1.1},
                    {"parameter": {"choice_num": 60}, "value": {"default": 1.2, "tmp": 2}},
                    {"parameter": {"choice_num": 50}, "value": 1.3}]
        tuner.import_data(data)
        logger.info("Imported data successfully in the middle")
        # generate parameters again
        parameters = tuner.generate_multiple_parameters([3])
        tuner.receive_trial_result(3, parameters[0], random.uniform(-100, 100))

    def test_grid_search(self):
        self.exhaustive = True
        tuner_fn = lambda: GridSearchTuner()
        self.search_space_test_all(tuner_fn,
                                   supported_types=["choice", "randint", "quniform"])
        self.import_data_test(tuner_fn)

    def test_tpe(self):
        tuner_fn = lambda: HyperoptTuner("tpe")
        self.search_space_test_all(tuner_fn,
                                   ignore_types=["uniform_equal", "qloguniform_equal", "loguniform_equal", "quniform_clip_2"])
        # NOTE: types are ignored because `tpe.py line 465, in adaptive_parzen_normal assert prior_sigma > 0`
        self.import_data_test(tuner_fn)

    def test_random_search(self):
        tuner_fn = lambda: HyperoptTuner("random_search")
        self.search_space_test_all(tuner_fn)
        self.import_data_test(tuner_fn)

    def test_anneal(self):
        tuner_fn = lambda: HyperoptTuner("anneal")
        self.search_space_test_all(tuner_fn)
        self.import_data_test(tuner_fn)

    def test_smac(self):
        if sys.platform == "win32":
            return  # smac doesn't work on windows
        tuner_fn = lambda: SMACTuner()
        self.search_space_test_all(tuner_fn,
                                   supported_types=["choice", "randint", "uniform", "quniform", "loguniform"])
        self.import_data_test(tuner_fn)

    def test_batch(self):
        self.exhaustive = True
        tuner_fn = lambda: BatchTuner()
        self.search_space_test_all(tuner_fn,
                                   supported_types=["choice"])
        self.import_data_test(tuner_fn)

    def test_evolution(self):
        # Needs enough population size, otherwise it will throw a runtime error
        tuner_fn = lambda: EvolutionTuner(population_size=100)
        self.search_space_test_all(tuner_fn)
        self.import_data_test(tuner_fn)

    def test_gp(self):
        self.test_round = 1  # NOTE: GP tuner got hanged for multiple testing round
        tuner_fn = lambda: GPTuner()
        self.search_space_test_all(tuner_fn,
                                   supported_types=["choice", "randint", "uniform", "quniform", "loguniform",
                                                    "qloguniform"],
                                   ignore_types=["normal", "lognormal", "qnormal", "qlognormal"],
                                   fail_types=["choice_str", "choice_mixed"])
        self.import_data_test(tuner_fn, "choice_num")

    def test_metis(self):
        self.test_round = 1  # NOTE: Metis tuner got hanged for multiple testing round
        tuner_fn = lambda: MetisTuner()
        self.search_space_test_all(tuner_fn,
                                   supported_types=["choice", "randint", "uniform", "quniform"],
                                   fail_types=["choice_str", "choice_mixed"])
        self.import_data_test(tuner_fn, "choice_num")

    def test_networkmorphism(self):
        pass

    def test_ppo(self):
        pass

    def test_pbt(self):
        self.search_space_test_all(lambda: PBTTuner(
            all_checkpoint_dir=os.path.expanduser("~/nni/checkpoint/test/"),
            population_size=12
        ))
        self.search_space_test_all(lambda: PBTTuner(
            all_checkpoint_dir=os.path.expanduser("~/nni/checkpoint/test/"),
            population_size=100
        ))
        self.import_data_test_for_pbt()

    def tearDown(self):
        file_list = glob.glob("smac3*") + ["param_config_space.pcs", "scenario.txt", "model_path"]
        for file in file_list:
            if os.path.exists(file):
                if os.path.isdir(file):
                    shutil.rmtree(file)
                else:
                    os.remove(file)

    def test_regularized_evolution_tuner(self):
        tuner_fn = lambda: RegularizedEvolutionTuner()
        self.nas_search_space_test_all(tuner_fn)


if __name__ == '__main__':
    main()
