#####################################################
# Copyright (c) Xuanyi Dong [GitHub D-X-Y], 2020.08 #
##############################################################################
# NATS-Bench: Benchmarking NAS algorithms for Architecture Topology and Size #
##############################################################################
# The history of benchmark files are as follows,                             #
# where the format is (the name is NATS-tss-[version]-[md5].pickle.pbz2)     #
# [2020.08.31] NATS-tss-v1_0-3ffb9.pickle.pbz2                               #
##############################################################################
# pylint: disable=line-too-long
"""The API for topology search space in NATS-Bench."""
import collections
import copy
import os
import random
from typing import Any, Dict, List, Optional, Text, Union

from nats_bench.api_utils import ArchResults
from nats_bench.api_utils import NASBenchMetaAPI
from nats_bench.api_utils import get_torch_home
from nats_bench.api_utils import nats_is_dir
from nats_bench.api_utils import nats_is_file
from nats_bench.api_utils import PICKLE_EXT
from nats_bench.api_utils import pickle_load
from nats_bench.api_utils import time_string

import numpy as np


ALL_BASE_NAMES = ['NATS-tss-v1_0-3ffb9']


def print_information(information, extra_info=None, show=False):
  """print out the information of a given ArchResults."""
  dataset_names = information.get_dataset_names()
  strings = [
      information.arch_str,
      'datasets : {:}, extra-info : {:}'.format(dataset_names, extra_info)
  ]

  def metric2str(loss, acc):
    return 'loss = {:.3f} & top1 = {:.2f}%'.format(loss, acc)

  for dataset in dataset_names:
    metric = information.get_compute_costs(dataset)
    flop, param, latency = metric['flops'], metric['params'], metric['latency']
    str1 = '{:14s} FLOP={:6.2f} M, Params={:.3f} MB, latency={:} ms.'.format(
        dataset, flop, param,
        '{:.2f}'.format(latency *
                        1000) if latency is not None and latency > 0 else None)
    train_info = information.get_metrics(dataset, 'train')
    if dataset == 'cifar10-valid':
      valid_info = information.get_metrics(dataset, 'x-valid')
      str2 = '{:14s} train : [{:}], valid : [{:}]'.format(
          dataset, metric2str(train_info['loss'], train_info['accuracy']),
          metric2str(valid_info['loss'], valid_info['accuracy']))
    elif dataset == 'cifar10':
      test__info = information.get_metrics(dataset, 'ori-test')
      str2 = '{:14s} train : [{:}], test  : [{:}]'.format(
          dataset, metric2str(train_info['loss'], train_info['accuracy']),
          metric2str(test__info['loss'], test__info['accuracy']))
    else:
      valid_info = information.get_metrics(dataset, 'x-valid')
      test__info = information.get_metrics(dataset, 'x-test')
      str2 = '{:14s} train : [{:}], valid : [{:}], test : [{:}]'.format(
          dataset, metric2str(train_info['loss'], train_info['accuracy']),
          metric2str(valid_info['loss'], valid_info['accuracy']),
          metric2str(test__info['loss'], test__info['accuracy']))
    strings += [str1, str2]
  if show: print('\n'.join(strings))
  return strings


class NATStopology(NASBenchMetaAPI):
  """This is the class for the API of topology search space in NATS-Bench."""

  def __init__(self,
               file_path_or_dict: Optional[Union[Text, Dict[Text, Any]]] = None,
               fast_mode: bool = False,
               verbose: bool = True):
    """The initialization function that takes the dataset file path (or a dict loaded from that path) as input."""
    self._all_base_names = ALL_BASE_NAMES
    self.filename = None
    self._search_space_name = 'topology'
    self._fast_mode = fast_mode
    self._archive_dir = None
    self._full_train_epochs = 200
    self.reset_time()
    if file_path_or_dict is None:
      if self._fast_mode:
        self._archive_dir = os.path.join(
            get_torch_home(), '{:}-simple'.format(ALL_BASE_NAMES[-1]))
      else:
        file_path_or_dict = os.path.join(
            get_torch_home(), '{:}.{:}'.format(
                ALL_BASE_NAMES[-1], PICKLE_EXT))
      print('{:} Try to use the default NATS-Bench (topology) path from '
            'fast_mode={:} and path={:}.'.format(time_string(), self._fast_mode, file_path_or_dict))
    if isinstance(file_path_or_dict, str):
      file_path_or_dict = str(file_path_or_dict)
      if verbose:
        print('{:} Try to create the NATS-Bench (topology) api '
              'from {:} with fast_mode={:}'.format(
                  time_string(), file_path_or_dict, fast_mode))
      if not nats_is_file(file_path_or_dict) and not nats_is_dir(
          file_path_or_dict):
        raise ValueError('{:} is neither a file or a dir.'.format(
            file_path_or_dict))
      self.filename = os.path.basename(file_path_or_dict)
      if fast_mode:
        if nats_is_file(file_path_or_dict):
          raise ValueError('fast_mode={:} must feed the path for directory '
                           ': {:}'.format(fast_mode, file_path_or_dict))
        else:
          self._archive_dir = file_path_or_dict
      else:
        if nats_is_dir(file_path_or_dict):
          raise ValueError('fast_mode={:} must feed the path for file '
                           ': {:}'.format(fast_mode, file_path_or_dict))
        else:
          file_path_or_dict = pickle_load(file_path_or_dict)
    elif isinstance(file_path_or_dict, dict):
      file_path_or_dict = copy.deepcopy(file_path_or_dict)
    self.verbose = verbose
    if isinstance(file_path_or_dict, dict):
      keys = ('meta_archs', 'arch2infos', 'evaluated_indexes')
      for key in keys:
        if key not in file_path_or_dict:
          raise ValueError('Can not find key[{:}] in the dict'.format(key))
      self.meta_archs = copy.deepcopy(file_path_or_dict['meta_archs'])
      # NOTE(xuanyidong): This is a dict mapping each architecture to a dict,
      # where the key is #epochs and the value is ArchResults
      self.arch2infos_dict = collections.OrderedDict()
      self._avaliable_hps = set()
      for xkey in sorted(list(file_path_or_dict['arch2infos'].keys())):
        all_infos = file_path_or_dict['arch2infos'][xkey]
        hp2archres = collections.OrderedDict()
        for hp_key, results in all_infos.items():
          hp2archres[hp_key] = ArchResults.create_from_state_dict(results)
          self._avaliable_hps.add(hp_key)  # save the avaliable hyper-parameter
        self.arch2infos_dict[xkey] = hp2archres
      self.evaluated_indexes = set(file_path_or_dict['evaluated_indexes'])
    elif self.archive_dir is not None:
      benchmark_meta = pickle_load('{:}/meta.{:}'.format(
          self.archive_dir, PICKLE_EXT))
      self.meta_archs = copy.deepcopy(benchmark_meta['meta_archs'])
      self.arch2infos_dict = collections.OrderedDict()
      self._avaliable_hps = set()
      self.evaluated_indexes = set()
    else:
      raise ValueError('file_path_or_dict [{:}] must be a dict or archive_dir '
                       'must be set'.format(type(file_path_or_dict)))
    self.archstr2index = {}
    for idx, arch in enumerate(self.meta_archs):
      if arch in self.archstr2index:
        raise ValueError('This [{:}]-th arch {:} already in the '
                         'dict ({:}).'.format(
                             idx, arch, self.archstr2index[arch]))
      self.archstr2index[arch] = idx
    if self.verbose:
      print('{:} Create NATS-Bench (topology) done with {:}/{:} architectures '
            'avaliable.'.format(time_string(),
                                len(self.evaluated_indexes),
                                len(self.meta_archs)))

  def query_info_str_by_arch(self, arch, hp: Text = '12'):
    """Query the information of a specific architecture.

    Args:
      arch: it can be an architecture index or an architecture string.

      hp: the hyperparamete indicator, could be 12 or 200. The difference
          between these three configurations are the number of training epochs.

    Returns:
      ArchResults instance
    """
    if self.verbose:
      print('{:} Call query_info_str_by_arch with arch={:}'
            'and hp={:}'.format(time_string(), arch, hp))
    return self._query_info_str_by_arch(arch, hp, print_information)

  def get_more_info(self,
                    index,
                    dataset,
                    iepoch=None,
                    hp: Text = '12',
                    is_random: bool = True):
    """Return the metric for the `index`-th architecture."""
    if self.verbose:
      print('{:} Call the get_more_info function with index={:}, dataset={:}, '
            'iepoch={:}, hp={:}, and is_random={:}.'.format(
                time_string(), index, dataset, iepoch, hp, is_random))
    index = self.query_index_by_arch(index)  # To avoid the input is a string or an instance of a arch object
    self._prepare_info(index)
    if index not in self.arch2infos_dict:
      raise ValueError('Did not find {:} from arch2infos_dict.'.format(index))
    archresult = self.arch2infos_dict[index][str(hp)]
    # if randomly select one trial, select the seed at first
    if isinstance(is_random, bool) and is_random:
      seeds = archresult.get_dataset_seeds(dataset)
      is_random = random.choice(seeds)
    # collect the training information
    train_info = archresult.get_metrics(dataset, 'train', iepoch=iepoch, is_random=is_random)
    total = train_info['iepoch'] + 1
    xinfo = {
        'train-loss':
            train_info['loss'],
        'train-accuracy':
            train_info['accuracy'],
        'train-per-time':
            train_info['all_time'] /
            total if train_info['all_time'] is not None else None,
        'train-all-time':
            train_info['all_time']
    }
    # collect the evaluation information
    if dataset == 'cifar10-valid':
      valid_info = archresult.get_metrics(dataset, 'x-valid', iepoch=iepoch, is_random=is_random)
      try:
        test_info = archresult.get_metrics(dataset, 'ori-test', iepoch=iepoch, is_random=is_random)
      except Exception as unused_e:  # pylint: disable=broad-except
        test_info = None
      valtest_info = None
      xinfo['comment'] = 'In this dict, train-loss/accuracy/time is the metric on the train set of CIFAR-10. The test-loss/accuracy/time is the performance of the CIFAR-10 test set after training on the train set by {:} epochs. The per-time and total-time indicate the per epoch and total time costs, respectively.'.format(hp)
    else:
      if dataset == 'cifar10':
        xinfo['comment'] = 'In this dict, train-loss/accuracy/time is the metric on the train+valid sets of CIFAR-10. The test-loss/accuracy/time is the performance of the CIFAR-10 test set after training on the train+valid sets by {:} epochs. The per-time and total-time indicate the per epoch and total time costs, respectively.'.format(hp)
      try:  # collect results on the proposed test set
        if dataset == 'cifar10':
          test_info = archresult.get_metrics(dataset, 'ori-test', iepoch=iepoch, is_random=is_random)
        else:
          test_info = archresult.get_metrics(dataset, 'x-test', iepoch=iepoch, is_random=is_random)
      except Exception as unused_e:  # pylint: disable=broad-except
        test_info = None
      try:  # collect results on the proposed validation set
        valid_info = archresult.get_metrics(dataset, 'x-valid', iepoch=iepoch, is_random=is_random)
      except Exception as unused_e:  # pylint: disable=broad-except
        valid_info = None
      try:
        if dataset != 'cifar10':
          valtest_info = archresult.get_metrics(dataset, 'ori-test', iepoch=iepoch, is_random=is_random)
        else:
          valtest_info = None
      except Exception as unused_e:  # pylint: disable=broad-except
        valtest_info = None
    if valid_info is not None:
      xinfo['valid-loss'] = valid_info['loss']
      xinfo['valid-accuracy'] = valid_info['accuracy']
      xinfo['valid-per-time'] = valid_info['all_time'] / total if valid_info['all_time'] is not None else None
      xinfo['valid-all-time'] = valid_info['all_time']
    if test_info is not None:
      xinfo['test-loss'] = test_info['loss']
      xinfo['test-accuracy'] = test_info['accuracy']
      xinfo['test-per-time'] = test_info['all_time'] / total if test_info['all_time'] is not None else None
      xinfo['test-all-time'] = test_info['all_time']
    if valtest_info is not None:
      xinfo['valtest-loss'] = valtest_info['loss']
      xinfo['valtest-accuracy'] = valtest_info['accuracy']
      xinfo['valtest-per-time'] = valtest_info['all_time'] / total if valtest_info['all_time'] is not None else None
      xinfo['valtest-all-time'] = valtest_info['all_time']
    return xinfo

  def show(self, index: int = -1) -> None:
    """This function will print the information of a specific (or all) architecture(s)."""
    self._show(index, print_information)

  @staticmethod
  def str2lists(arch_str: Text) -> List[Any]:
    """Shows how to read the string-based architecture encoding.

    Args:
      arch_str: the input is a string indicates the architecture topology, such as
                    |nor_conv_1x1~0|+|none~0|none~1|+|none~0|none~1|skip_connect~2|
    Returns:
      a list of tuple, contains multiple (op, input_node_index) pairs.

    [USAGE]
    It is the same as the `str2structure` func in AutoDL-Projects:
      `github.com/D-X-Y/AutoDL-Projects/lib/models/cell_searchs/genotypes.py`
    ```
      arch = api.str2lists( '|nor_conv_1x1~0|+|none~0|none~1|+|none~0|none~1|skip_connect~2|' )
      print ('there are {:} nodes in this arch'.format(len(arch)+1)) # arch is a list
      for i, node in enumerate(arch):
        print('the {:}-th node is the sum of these {:} nodes with op: {:}'.format(i+1, len(node), node))
    ```
    """
    node_strs = arch_str.split('+')
    genotypes = []
    for unused_i, node_str in enumerate(node_strs):
      inputs = list(filter(lambda x: x != '', node_str.split('|')))  # pylint: disable=g-explicit-bool-comparison
      for xinput in inputs:
        assert len(
            xinput.split('~')) == 2, 'invalid input length : {:}'.format(xinput)
      inputs = (xi.split('~') for xi in inputs)
      input_infos = tuple((op, int(idx)) for (op, idx) in inputs)
      genotypes.append(input_infos)
    return genotypes

  @staticmethod
  def str2matrix(arch_str: Text,
                 search_space: List[Text] = ('none', 'skip_connect', 'nor_conv_1x1', 'nor_conv_3x3', 'avg_pool_3x3')) -> np.ndarray:
    """Convert the string-based architecture encoding to the encoding strategy in NAS-Bench-101.

    Args:
      arch_str: the input is a string indicates the architecture topology, such as
                    |nor_conv_1x1~0|+|none~0|none~1|+|none~0|none~1|skip_connect~2|
      search_space: a list of operation string, the default list is the topology search space for NATS-BENCH.
        the default value should be be consistent with this line https://github.com/D-X-Y/AutoDL-Projects/blob/main/lib/models/cell_operations.py#L24

    Returns:
      the numpy matrix (2-D np.ndarray) representing the DAG of this architecture topology

    [USAGE]
      matrix = api.str2matrix( '|nor_conv_1x1~0|+|none~0|none~1|+|none~0|none~1|skip_connect~2|' )
      This matrix is 4-by-4 matrix representing a cell with 4 nodes (only the lower left triangle is useful).
         [ [0, 0, 0, 0],  # the first line represents the input (0-th) node
           [2, 0, 0, 0],  # the second line represents the 1-st node, is calculated by 2-th-op( 0-th-node )
           [0, 0, 0, 0],  # the third line represents the 2-nd node, is calculated by 0-th-op( 0-th-node ) + 0-th-op( 1-th-node )
           [0, 0, 1, 0] ] # the fourth line represents the 3-rd node, is calculated by 0-th-op( 0-th-node ) + 0-th-op( 1-th-node ) + 1-th-op( 2-th-node )
      In the topology search space in NATS-BENCH, 0-th-op is 'none', 1-th-op is 'skip_connect',
         2-th-op is 'nor_conv_1x1', 3-th-op is 'nor_conv_3x3', 4-th-op is 'avg_pool_3x3'.
    [NOTE]
      If a node has two input-edges from the same node, this function does not work. One edge will be overlapped.
    """
    node_strs = arch_str.split('+')
    num_nodes = len(node_strs) + 1
    matrix = np.zeros((num_nodes, num_nodes))
    for i, node_str in enumerate(node_strs):
      inputs = list(filter(lambda x: x != '', node_str.split('|')))  # pylint: disable=g-explicit-bool-comparison
      for xinput in inputs:
        assert len(xinput.split('~')) == 2, 'invalid input length : {:}'.format(xinput)
      for xi in inputs:
        op, idx = xi.split('~')
        if op not in search_space: raise ValueError('this op ({:}) is not in {:}'.format(op, search_space))
        op_idx, node_idx = search_space.index(op), int(idx)
        matrix[i+1, node_idx] = op_idx
    return matrix