import re 

from simplemma import lemmatize


def flatten(xss):
    return [x for xs in xss for x in xs]
    

def remove_all_brackets(text):
    return re.sub(r'[\(\{\[].*?[\)\}\]]', '', text)


def lemmatizing(x):
    if x == "":
        return ""
    return lemmatize(x, lang="cs")


def build_reverse_dictionary(dictionary, apply_lemmatizing=False):
    reverse_dictionary = {}
    for key, values in dictionary.items():
        for value in values:
            reverse_dictionary[value] = key
            if apply_lemmatizing:
                temp = lemmatizing(value)
                if temp != value:
                    reverse_dictionary[temp] = key
    return reverse_dictionary


def split_gazetteers_for_single_token_match(gazetteers):
    result = {}
    for k, v in gazetteers.items():
        result[k] = set(flatten([vv.split(" ") for vv in v]))
        result[k] = {x for x in result[k] if len(x) > 2}
    return result


def preprocess_gazetteers(gazetteers, config):
    if config["split_person"]: 
        gazetteers["PER"].update(set([x for x in flatten([v.split(" ") for v in gazetteers["PER"]]) if len(x) > 2]))
    if config["lemmatize"]:
        for k, v in gazetteers.items():
            gazetteers[k] = set(flatten([(vv, lemmatizing(vv)) for vv in v if len(vv) > 2]))
    if config["remove_brackets"]:
        for k, v in gazetteers.items():
            gazetteers[k] = {remove_all_brackets(vv).strip() for vv in v if len(remove_all_brackets(vv).strip()) > 2}
    if config["remove_numeric"]:
        for k, v in gazetteers.items():
            gazetteers[k] = {vv for vv in v if not vv.isnumeric()}
    if config["techniq_for_matching"] != "single":
        gazetteers = split_gazetteers_for_single_token_match(gazetteers)
    return gazetteers