import os
import zipfile
from os.path import join
from urllib.error import HTTPError

import pandas as pd

from data.base import Dataset, LabelledCollection
from quapy.data.preprocessing import text2tfidf, reduce_columns
from quapy.data.reader import *
from quapy.util import download_file_if_not_exists, download_file, get_quapy_home, pickled_resource

REVIEWS_SENTIMENT_DATASETS = ['hp', 'kindle', 'imdb']
TWITTER_SENTIMENT_DATASETS_TEST = ['gasp', 'hcr', 'omd', 'sanders',
                              'semeval13', 'semeval14', 'semeval15', 'semeval16',
                              'sst', 'wa', 'wb']
TWITTER_SENTIMENT_DATASETS_TRAIN = ['gasp', 'hcr', 'omd', 'sanders',
                                 'semeval', 'semeval16',
                                 'sst', 'wa', 'wb']


def fetch_reviews(dataset_name, tfidf=False, min_df=None, data_home=None, pickle=False):
    """
    Load a Reviews dataset as a Dataset instance, as used in:
    Esuli, A., Moreo, A., and Sebastiani, F. "A recurrent neural network for sentiment quantification."
    Proceedings of the 27th ACM International Conference on Information and Knowledge Management. 2018.
    :param dataset_name: the name of the dataset: valid ones are 'hp', 'kindle', 'imdb'
    :param tfidf: set to True to transform the raw documents into tfidf weighted matrices
    :param min_df: minimun number of documents that should contain a term in order for the term to be
    kept (ignored if tfidf==False)
    :param data_home: specify the quapy home directory where collections will be dumped (leave empty to use the default
    ~/quay_data/ directory)
    :param pickle: set to True to pickle the Dataset object the first time it is generated, in order to allow for
    faster subsequent invokations
    :return: a Dataset instance
    """
    assert dataset_name in REVIEWS_SENTIMENT_DATASETS, \
        f'Name {dataset_name} does not match any known dataset for sentiment reviews. ' \
        f'Valid ones are {REVIEWS_SENTIMENT_DATASETS}'
    if data_home is None:
        data_home = get_quapy_home()

    URL_TRAIN = f'https://zenodo.org/record/4117827/files/{dataset_name}_train.txt'
    URL_TEST = f'https://zenodo.org/record/4117827/files/{dataset_name}_test.txt'
    os.makedirs(join(data_home, 'reviews'), exist_ok=True)
    train_path = join(data_home, 'reviews', dataset_name, 'train.txt')
    test_path = join(data_home, 'reviews', dataset_name, 'test.txt')
    download_file_if_not_exists(URL_TRAIN, train_path)
    download_file_if_not_exists(URL_TEST, test_path)

    pickle_path = None
    if pickle:
        pickle_path = join(data_home, 'reviews', 'pickle', f'{dataset_name}.pkl')
    data = pickled_resource(pickle_path, Dataset.load, train_path, test_path, from_text)

    if tfidf:
        text2tfidf(data, inplace=True)
        if min_df is not None:
            reduce_columns(data, min_df=min_df, inplace=True)

    data.name = dataset_name

    return data


def fetch_twitter(dataset_name, for_model_selection=False, min_df=None, data_home=None, pickle=False):
    """
    Load a Twitter dataset as a Dataset instance, as used in:
    Gao, W., Sebastiani, F.: From classification to quantification in tweet sentiment analysis.
    Social Network Analysis and Mining6(19), 1–22 (2016)
    The datasets 'semeval13', 'semeval14', 'semeval15' share the same training set.

    :param dataset_name: the name of the dataset: valid ones are 'gasp', 'hcr', 'omd', 'sanders', 'semeval13',
    'semeval14', 'semeval15', 'semeval16', 'sst', 'wa', 'wb'
    :param for_model_selection: if True, then returns the train split as the training set and the devel split
    as the test set; if False, then returns the train+devel split as the training set and the test set as the
    test set
    :param min_df: minimun number of documents that should contain a term in order for the term to be kept
    :param data_home: specify the quapy home directory where collections will be dumped (leave empty to use the default
    ~/quay_data/ directory)
    :param pickle: set to True to pickle the Dataset object the first time it is generated, in order to allow for
    faster subsequent invokations
    :return: a Dataset instance
    """
    assert dataset_name in TWITTER_SENTIMENT_DATASETS_TRAIN + TWITTER_SENTIMENT_DATASETS_TEST, \
        f'Name {dataset_name} does not match any known dataset for sentiment twitter. ' \
        f'Valid ones are {TWITTER_SENTIMENT_DATASETS_TRAIN} for model selection and ' \
        f'{TWITTER_SENTIMENT_DATASETS_TEST} for test (datasets "semeval14", "semeval15", "semeval16" share ' \
        f'a common training set "semeval")'
    if data_home is None:
        data_home = get_quapy_home()

    URL = 'https://zenodo.org/record/4255764/files/tweet_sentiment_quantification_snam.zip'
    unzipped_path = join(data_home, 'tweet_sentiment_quantification_snam')
    if not os.path.exists(unzipped_path):
        downloaded_path = join(data_home, 'tweet_sentiment_quantification_snam.zip')
        download_file(URL, downloaded_path)
        with zipfile.ZipFile(downloaded_path) as file:
            file.extractall(data_home)
        os.remove(downloaded_path)

    if dataset_name in {'semeval13', 'semeval14', 'semeval15'}:
        trainset_name = 'semeval'
        testset_name  = 'semeval' if for_model_selection else dataset_name
        print(f"the training and development sets for datasets 'semeval13', 'semeval14', 'semeval15' are common "
              f"(called 'semeval'); returning trainin-set='{trainset_name}' and test-set={testset_name}")
    else:
        if dataset_name == 'semeval' and for_model_selection==False:
            raise ValueError('dataset "semeval" can only be used for model selection. '
                             'Use "semeval13", "semeval14", or "semeval15" for model evaluation.')
        trainset_name = testset_name = dataset_name

    if for_model_selection:
        train = join(unzipped_path, 'train', f'{trainset_name}.train.feature.txt')
        test  = join(unzipped_path, 'test', f'{testset_name}.dev.feature.txt')
    else:
        train = join(unzipped_path, 'train', f'{trainset_name}.train+dev.feature.txt')
        if dataset_name == 'semeval16':  # there is a different test name in the case of semeval16 only
            test = join(unzipped_path, 'test', f'{testset_name}.dev-test.feature.txt')
        else:
            test = join(unzipped_path, 'test', f'{testset_name}.test.feature.txt')

    pickle_path = None
    if pickle:
        mode = "train-dev" if for_model_selection else "train+dev-test"
        pickle_path = join(unzipped_path, 'pickle', f'{testset_name}.{mode}.pkl')
    data = pickled_resource(pickle_path, Dataset.load, train, test, from_sparse)

    if min_df is not None:
        reduce_columns(data, min_df=min_df, inplace=True)

    data.name = dataset_name

    return data


UCI_DATASETS = ['acute.a', 'acute.b',
                'balance.1', 'balance.2', 'balance.3',
                'breast-cancer',
                'cmc.1', 'cmc.2', 'cmc.3',
                'ctg.1', 'ctg.2', 'ctg.3',
                #'diabetes', # <-- I haven't found this one...
                'german',
                'haberman',
                'ionosphere',
                'iris.1', 'iris.2', 'iris.3',
                'mammographic',
                'pageblocks.5',
                #'phoneme', # <-- I haven't found this one...
                'semeion',
                'sonar',
                'spambase',
                'spectf',
                'tictactoe',
                'transfusion'] # ongoing...

def fetch_UCIDataset(dataset_name, data_home=None, verbose=False, test_split=0.3):

    assert dataset_name in UCI_DATASETS, \
        f'Name {dataset_name} does not match any known dataset from the UCI Machine Learning datasets repository. ' \
        f'Valid ones are {UCI_DATASETS}'
    if data_home is None:
        data_home = get_quapy_home()

    dataset_fullname = {
        'acute.a': 'Acute Inflammations (urinary bladder)',
        'acute.b': 'Acute Inflammations (renal pelvis)',
        'balance.1': 'Balance Scale Weight & Distance Database (left)',
        'balance.2': 'Balance Scale Weight & Distance Database (balanced)',
        'balance.3': 'Balance Scale Weight & Distance Database (right)',
        'breast-cancer':  'Breast Cancer Wisconsin (Original)',
        'cmc.1': 'Contraceptive Method Choice (no use)',
        'cmc.2': 'Contraceptive Method Choice (long term)',
        'cmc.3': 'Contraceptive Method Choice (short term)',
        'ctg.1': 'Cardiotocography Data Set (normal)',
        'ctg.2': 'Cardiotocography Data Set (suspect)',
        'ctg.3': 'Cardiotocography Data Set (pathologic)',
        'german': 'Statlog German Credit Data',
        'haberman': "Haberman's Survival Data",
        'ionosphere': 'Johns Hopkins University Ionosphere DB',
        'iris.1': 'Iris Plants Database(x)',
        'iris.2': 'Iris Plants Database(versicolour)',
        'iris.3': 'Iris Plants Database(virginica)',
        'mammographic': 'Mammographic Mass',
        'pageblocks.5': 'Page Blocks Classification (5)',
        'semeion': 'Semeion Handwritten Digit (8)',
        'sonar': 'Sonar, Mines vs. Rocks',
        'spambase': 'Spambase Data Set',
        'spectf': 'SPECTF Heart Data',
        'tictactoe': 'Tic-Tac-Toe Endgame Database',
        'transfusion': 'Blood Transfusion Service Center Data Set '
    }

    # the identifier is an alias for the dataset group, it's part of the url data-folder, and is the name we use
    # to download the raw dataset
    identifier_map = {
        'acute.a': 'acute',
        'acute.b': 'acute',
        'balance.1': 'balance-scale',
        'balance.2': 'balance-scale',
        'balance.3': 'balance-scale',
        'breast-cancer': 'breast-cancer-wisconsin',
        'cmc.1': 'cmc',
        'cmc.2': 'cmc',
        'cmc.3': 'cmc',
        'ctg.1': '00193',
        'ctg.2': '00193',
        'ctg.3': '00193',
        'german': 'statlog/german',
        'haberman': 'haberman',
        'ionosphere': 'ionosphere',
        'iris.1': 'iris',
        'iris.2': 'iris',
        'iris.3': 'iris',
        'mammographic': 'mammographic-masses',
        'pageblocks.5': 'page-blocks',
        'semeion': 'semeion',
        'sonar': 'undocumented/connectionist-bench/sonar',
        'spambase': 'spambase',
        'spectf': 'spect',
        'tictactoe': 'tic-tac-toe',
        'transfusion': 'blood-transfusion'
    }

    # the filename is the name of the file within the data_folder indexed by the identifier
    file_name = {
        'acute': 'diagnosis.data',
        '00193': 'CTG.xls',
        'statlog/german': 'german.data-numeric',
        'mammographic-masses': 'mammographic_masses.data',
        'page-blocks': 'page-blocks.data.Z',
        'undocumented/connectionist-bench/sonar': 'sonar.all-data',
        'spect': ['SPECTF.train', 'SPECTF.test'],
        'blood-transfusion': 'transfusion.data'
    }

    # the filename containing the dataset description (if any)
    desc_name = {
        'acute': 'diagnosis.names',
        '00193': None,
        'statlog/german': 'german.doc',
        'mammographic-masses': 'mammographic_masses.names',
        'undocumented/connectionist-bench/sonar': 'sonar.names',
        'spect': 'SPECTF.names',
        'blood-transfusion': 'transfusion.names'
    }

    identifier = identifier_map[dataset_name]
    filename = file_name.get(identifier, f'{identifier}.data')
    descfile = desc_name.get(identifier, f'{identifier}.names')
    fullname = dataset_fullname[dataset_name]

    URL = f'http://archive.ics.uci.edu/ml/machine-learning-databases/{identifier}'
    data_dir = join(data_home, 'uci_datasets', identifier)
    if isinstance(filename, str):  # filename could be a list of files, in which case it will be processed later
        data_path = join(data_dir, filename)
        download_file_if_not_exists(f'{URL}/{filename}', data_path)

    if descfile:
        try:
            download_file_if_not_exists(f'{URL}/{descfile}', f'{data_dir}/{descfile}')
            if verbose:
                print(open(f'{data_dir}/{descfile}', 'rt').read())
        except Exception:
            print('could not read the description file')
    elif verbose:
        print('no file description available')

    print(f'Loading {dataset_name} ({fullname})')
    if identifier == 'acute':
        df = pd.read_csv(data_path, header=None, encoding='utf-16', sep='\t')
        if dataset_name == 'acute.a':
            y = binarize(df[6], pos_class='yes')
        elif dataset_name == 'acute.b':
            y = binarize(df[7], pos_class='yes')

        mintemp, maxtemp = 35, 42
        df[0] = df[0].apply(lambda x:(float(x.replace(',','.'))-mintemp)/(maxtemp-mintemp)).astype(float, copy=False)
        [df_replace(df, col) for col in range(1, 6)]
        X = df.loc[:, 0:5].values

    if identifier == 'balance-scale':
        df = pd.read_csv(data_path, header=None, sep=',')
        if dataset_name == 'balance.1':
            y = binarize(df[0], pos_class='L')
        elif dataset_name == 'balance.2':
            y = binarize(df[0], pos_class='B')
        elif dataset_name == 'balance.3':
            y = binarize(df[0], pos_class='R')
        X = df.loc[:, 1:].astype(float).values

    if identifier == 'breast-cancer-wisconsin':
        df = pd.read_csv(data_path, header=None, sep=',')
        Xy = df.loc[:, 1:10]
        Xy[Xy=='?']=np.nan
        Xy = Xy.dropna(axis=0)
        X = Xy.loc[:, 1:9]
        X = X.astype(float).values
        y = binarize(Xy[10], pos_class=4)

    if identifier == 'cmc':
        df = pd.read_csv(data_path, header=None, sep=',')
        X = df.loc[:, 0:8].astype(float).values
        y = df[9].astype(int).values
        if dataset_name == 'cmc.1':
            y = binarize(y, pos_class=1)
        elif dataset_name == 'cmc.2':
            y = binarize(y, pos_class=2)
        elif dataset_name == 'cmc.3':
            y = binarize(y, pos_class=3)

    if identifier == '00193':
        df = pd.read_excel(data_path, sheet_name='Data', skipfooter=3)
        df = df[list(range(1,24))] # select columns numbered (number 23 is the target label)
        # replaces the header with the first row
        new_header = df.iloc[0]  # grab the first row for the header
        df = df[1:]  # take the data less the header row
        df.columns = new_header  # set the header row as the df header
        X = df.iloc[:, 0:22].astype(float).values
        y = df['NSP'].astype(int).values
        if dataset_name == 'ctg.1':
            y = binarize(y, pos_class=1)  # 1==Normal
        elif dataset_name == 'ctg.2':
            y = binarize(y, pos_class=2)  # 2==Suspect
        elif dataset_name == 'ctg.3':
            y = binarize(y, pos_class=3)  # 3==Pathologic

    if identifier == 'statlog/german':
        df = pd.read_csv(data_path, header=None, delim_whitespace=True)
        X = df.iloc[:, 0:24].astype(float).values
        y = df[24].astype(int).values
        y = binarize(y, pos_class=1)

    if identifier == 'haberman':
        df = pd.read_csv(data_path, header=None)
        X = df.iloc[:, 0:3].astype(float).values
        y = df[3].astype(int).values
        y = binarize(y, pos_class=2)

    if identifier == 'ionosphere':
        df = pd.read_csv(data_path, header=None)
        X = df.iloc[:, 0:34].astype(float).values
        y = df[34].values
        y = binarize(y, pos_class='b')

    if identifier == 'iris':
        df = pd.read_csv(data_path, header=None)
        X = df.iloc[:, 0:4].astype(float).values
        y = df[4].values
        if dataset_name == 'iris.1':
            y = binarize(y, pos_class='Iris-setosa')  # 1==Setosa
        elif dataset_name == 'iris.2':
            y = binarize(y, pos_class='Iris-versicolor')  # 2==Versicolor
        elif dataset_name == 'iris.3':
            y = binarize(y, pos_class='Iris-virginica')  # 3==Virginica

    if identifier == 'mammographic-masses':
        df = pd.read_csv(data_path, header=None, sep=',')
        Xy[df == '?'] = np.nan
        Xy = Xy.dropna(axis=0)
        X = Xy.iloc[:, 0:5]
        X = X.astype(float).values
        y = binarize(Xy.iloc[:,5], pos_class=1)

    if identifier == 'page-blocks':
        data_path_ = data_path.replace('.Z', '')
        if not os.path.exists(data_path_):
            raise FileNotFoundError(f'Warning: file {data_path_} does not exist. If this is the first time you '
                                    f'attempt to load this dataset, then you have to manually unzip the {data_path} '
                                    f'and name the extracted file {data_path_} (unfortunately, neither zipfile, nor '
                                    f'gzip can handle unix compressed files automatically -- there is a repo in GitHub '
                                    f'https://github.com/umeat/unlzw where the problem seems to be solved anyway).')
        df = pd.read_csv(data_path_, header=None, delim_whitespace=True)
        X = df.iloc[:, 0:10].astype(float).values
        y = df[10].values
        y = binarize(y, pos_class=5)  # 5==block "graphic"

    if identifier == 'semeion':
        df = pd.read_csv(data_path, header=None, delim_whitespace=True )
        X = df.iloc[:, 0:256].astype(float).values
        y = df[263].values  # 263 stands for digit 8 (labels are one-hot vectors from col 256-266)
        y = binarize(y, pos_class=1)

    if identifier == 'undocumented/connectionist-bench/sonar':
        df = pd.read_csv(data_path, header=None, sep=',')
        X = df.iloc[:, 0:60].astype(float).values
        y = df[60].values
        y = binarize(y, pos_class='R')

    if identifier == 'spambase':
        df = pd.read_csv(data_path, header=None, sep=',')
        X = df.iloc[:, 0:57].astype(float).values
        y = df[57].values
        y = binarize(y, pos_class=1)

    if identifier == 'spect':
        dfs = []
        for file in  filename:
            data_path = join(data_dir, file)
            download_file_if_not_exists(f'{URL}/{filename}', data_path)
            dfs.append(pd.read_csv(data_path, header=None, sep=','))
        df = pd.concat(dfs)
        X = df.iloc[:, 1:45].astype(float).values
        y = df[0].values
        y = binarize(y, pos_class=0)

    if identifier == 'tic-tac-toe':
        df = pd.read_csv(data_path, header=None, sep=',')
        X = df.iloc[:, 0:9].replace('o',0).replace('b',1).replace('x',2).values
        y = df[9].values
        y = binarize(y, pos_class='negative')

    if identifier == 'blood-transfusion':
        df = pd.read_csv(data_path, sep=',')
        X = df.iloc[:, 0:4].astype(float).values
        y = df.iloc[:, 4].values
        y = binarize(y, pos_class=1)

    data = LabelledCollection(X, y)
    data.stats()
    return Dataset(*data.split_stratified(1-test_split, random_state=0))


def df_replace(df, col, repl={'yes': 1, 'no':0}, astype=float):
    df[col] = df[col].apply(lambda x:repl[x]).astype(astype, copy=False)