import re
from copy import deepcopy

def add_slash_to_text_as_regex(text: str):
    if text is None or len(text) == 0:
        return text
    special_char_iter = re.finditer("\W", text)
    for special_iter in special_char_iter:
        if len(special_iter.group().strip()) == 0:
            continue
        replace = r"\{0}".format(special_iter.group())
        if replace not in text:
            text = re.sub(replace, replace, text)
    text = re.sub(r"\s+", r"\\s+", text)
    return text


def clean_text(text: str) -> str:
    # text = text.lower()
    # update the specical character which begin with \u, e.g \u2004 or \u00a0 to be space
    text = re.sub(r"\\u[A-Z0-9a-z]{4}", ' ', text)
    text = re.sub(r"( ){2,}", ' ', text.strip())
    return text


def get_most_similar_name(text: str, name_list: list, pre_common_word_list: list = None) -> str:
    """
    Get the most similar fund name from fund_name_list by jacard similarity
    """
    try:
        copy_fund_name_list = deepcopy(name_list)
        if text is None or len(text.split()) == 0 or \
                copy_fund_name_list is None or len(copy_fund_name_list) == 0:
            return None, None
        
        copy_fund_name_list = [replace_abbrevation(copy_fund_name) for copy_fund_name 
                               in copy_fund_name_list]

        # get common words in fund_name_list
        common_word_list = []
        if len(name_list) > 1:
            _, common_word_list = remove_common_word(copy_fund_name_list)
        if pre_common_word_list is not None and len(pre_common_word_list) > 0:
            common_word_list.extend([word for word in pre_common_word_list
                                     if word not in common_word_list])

        text = text.strip()
        text = remove_special_characters(text)
        text = replace_abbrevation(text)
        text_splits = text.split()
        if len(text_splits) == 1:
            text = split_words_without_space(text)
        else:
            new_splits = []
            for split in text_splits:
                if len(split) > 1:
                    new_splits.extend(split_words_without_space(split).split())
                else:
                    new_splits.append(split)

            lower_new_splits = [split.lower() for split in new_splits]
            for word in common_word_list:
                if word not in lower_new_splits:
                    # remove word in fund_name_list
                    for i in range(len(copy_fund_name_list)):
                        temp_splits = copy_fund_name_list[i].split()
                        copy_fund_name_list[i] = ' '.join([split for split in temp_splits 
                                                           if remove_special_characters(split).lower() != word])

            for i in range(len(copy_fund_name_list)):
                temp_splits = copy_fund_name_list[i].split()
                copy_fund_name_list[i] = ' '.join([split for split in temp_splits
                                                   if remove_special_characters(split).lower() not in ['fund', 'portfolio', 'class', 'share', 'shares']])
            final_splits = []
            for split in new_splits:
                if split.lower() not in ['fund', 'portfolio', 'class', 'share', 'shares']:
                    final_splits.append(split)

            text = ' '.join(final_splits)
        max_similarity = 0
        max_similarity_fund_name = None
        for fund_name, copy_fund_name in zip(name_list , copy_fund_name_list):
            copy_fund_name = remove_special_characters(copy_fund_name)
            copy_fund_name = split_words_without_space(copy_fund_name)
            similarity = get_jacard_similarity(text,
                                            copy_fund_name,
                                            need_remove_numeric_characters=False)
            if similarity > max_similarity:
                max_similarity = similarity
                max_similarity_fund_name = fund_name
            if max_similarity == 1:
                break
        if max_similarity < 0.35:
            return None, max_similarity
        return max_similarity_fund_name, max_similarity
    except Exception as e:
        print(e)
        return None, 0.0


def remove_common_word(text_list: list):
    if text_list is None or len(text_list) == 0:
        return text_list
    new_text_list = []
    for text in text_list:
        text = text.lower()
        text = remove_special_characters(text)
        text_splits = text.split()
        while 'fund' in text_splits:
            text_splits.remove('fund')
        while 'portfolio' in text_splits:
            text_splits.remove('portfolio')
        while 'share' in text_splits:
            text_splits.remove('share')
        while 'class' in text_splits:
            text_splits.remove('class')
        text = ' '.join(text_splits)
        new_text_list.append(text)
    # remove common word in new_text_list, such as 'Blackrock Global Fund' and 'Blackrock Growth Fund', then 'Blackrock', 'Fund' are common words
    # the result is ['Global', 'Growth']
    common_word_list = []
    new_text_splits_list = [text.split() for text in new_text_list]
    for i in range(len(new_text_splits_list)):
        for j in range(i+1, len(new_text_splits_list)):
            if common_word_list is None or len(common_word_list) == 0:
                common_word_list = list(
                    set(new_text_splits_list[i]).intersection(set(new_text_splits_list[j])))
            else:
                common_word_list = list(
                    set(common_word_list).intersection(set(new_text_splits_list[j])))
    common_word_list = list(set(common_word_list))
    for i in range(len(new_text_splits_list)):
        for common_word in common_word_list:
            if common_word in new_text_splits_list[i]:
                new_text_splits_list[i].remove(common_word)
    new_text_list = [' '.join(text_splits)
                     for text_splits in new_text_splits_list]
    return new_text_list, common_word_list


def split_words_without_space(text: str):
    """
    Split words without space, such as 'BlackrockGlobalFund' will be split to 'Blackrock', 'Global', 'Fund'
    """
    if text is None or len(text.strip()) == 0:
        return []
    text = text.strip()
    # splits = text.split()
    # if len(splits) > 1:
    #     return text
    # find all words with capital letter + lower letter
    regex = r'[A-Z][a-z]+'
    word_list = re.findall(regex, text)
    if len(word_list) > 0:
        for word in word_list:
            text = text.replace(word, ' ' + word + ' ')
        text = re.sub(r'(\s)+', ' ', text)
    return text.strip()


def remove_special_characters(text):
    text = re.sub(r'[^a-zA-Z0-9\s]', ' ', text)
    text = re.sub(r'\s+', ' ', text)
    text = text.strip()
    return text

def get_unique_words_text(text):
    text = remove_special_characters(text)
    text = text.lower()
    text_split = text.split()
    text_split = list(set(text_split))
    # sort the list
    text_split.sort()
    return_text = ' '.join(text_split)
    return return_text


def remove_numeric_characters(text):
    # remove numeric characters
    text = re.sub(r'\d+', ' ', text)
    text = re.sub(r'\s+', ' ', text)
    text = text.strip()
    return text


def get_jacard_similarity(text_left,
                          text_right,
                          need_remove_special_characters=True,
                          need_remove_numeric_characters=True):
    if need_remove_special_characters:
        text_left = remove_special_characters(text_left)
        text_right = remove_special_characters(text_right)
    if need_remove_numeric_characters:
        text_left = remove_numeric_characters(text_left)
        text_right = remove_numeric_characters(text_right)
    text_left = text_left.lower()
    text_right = text_right.lower()
    text_left = text_left.split()
    text_right = text_right.split()
    intersection = set(text_left).intersection(set(text_right))
    union = set(text_left).union(set(text_right))
    if len(union) > 0:
        return round(len(intersection) / len(union), 3)
    else:
        return 0

def get_beginning_common_words(text_list: list):
    """
    Get the beginning common words in text_list
    """
    if text_list is None or len(text_list) < 2:
        return []

    common_words_list = []
    first_text_split = text_list[0].split()
    for w_i, word in enumerate(first_text_split):
        all_same = True
        for text in text_list[1:]:
            text_split = text.split()
            if w_i >= len(text_split):
                all_same = False
                break
            if text_split[w_i] != word:
                all_same = False
                break
        if all_same:
            common_words_list.append(word)
        else:
            break
    
    return ' '.join(common_words_list).strip()

def replace_abbrevation(text: str):
    if text is None or len(text.strip()) == 0:
        return text
    text = text.strip()
    if 'swiss franc' in text.lower():
        text = re.sub(r'swiss\s+franc', 'CHF', text, flags=re.IGNORECASE)
    elif 'us dollar' in text.lower():
        text = re.sub(r'us\s+dollar', 'USD', text, flags=re.IGNORECASE)
    elif 'singapore dollar' in text.lower():
        text = re.sub(r'singapore\s+dollar', 'SGD', text, flags=re.IGNORECASE)
    elif 'hong kong dollar' in text.lower():
        text = re.sub(r'hong\s+kong\s+dollar', 'HKD', text, flags=re.IGNORECASE)
    elif 'hongkong dollar' in text.lower():
        text = re.sub(r'hongkong\s+dollar', 'HKD', text, flags=re.IGNORECASE)
    elif 'australian dollar' in text.lower():
        text = re.sub(r'australian\s+dollar', 'AUD', text, flags=re.IGNORECASE)
    elif 'japanese yen' in text.lower():
        text = re.sub(r'japanese\s+yen', 'JPY', text, flags=re.IGNORECASE)
    elif 'south african rand' in text.lower():
        text = re.sub(r'South\s+African\s+rand', 'ZAR', text, flags=re.IGNORECASE)
    elif 'canadian dollar' in text.lower():
        text = re.sub(r'canadian\s+dollar', 'CAD', text, flags=re.IGNORECASE)
    elif 'new zealand dollar' in text.lower():
        text = re.sub(r'new\s+zealand\s+dollar', 'NZD', text, flags=re.IGNORECASE)
    elif 'norwegian krone' in text.lower():
        text = re.sub(r'norwegian\s+krone', 'NOK', text, flags=re.IGNORECASE)
    elif 'danish krone' in text.lower():
        text = re.sub(r'danish\s+krone', 'DKK', text, flags=re.IGNORECASE)
    elif 'swedish krona' in text.lower():
        text = re.sub(r'swedish\s+krona', 'SEK', text, flags=re.IGNORECASE)
    elif 'swedish kronor' in text.lower():
        text = re.sub(r'swedish\s+kronor', 'SEK', text, flags=re.IGNORECASE)
    elif 'sterling' in text.lower().split():
        text = re.sub(r'sterling', 'GBP', text, flags=re.IGNORECASE)
    elif 'euro' in text.lower().split():
        text = re.sub(r'euro', 'EUR', text, flags=re.IGNORECASE)
    elif '€' in text.lower().split():
        text = re.sub(r'\€', 'EUR', text, flags=re.IGNORECASE)
    elif 'RMB' in text.lower().split():
        text = re.sub(r'RMB', 'CNY', text, flags=re.IGNORECASE)
    else:
        pass
    
    text_splits = text.split()
    new_text_splits = []
    for split in text_splits:
        if split.lower() in ['acc', 'acc.']:
            new_text_splits.append('Accumulation')
        elif split.lower() in ['inc', 'inc.']:
            new_text_splits.append('Income')
        elif split.lower() in ['dist', 'dist.']:
            new_text_splits.append('Distribution')
        elif split.lower() in ['inv', 'inv.']:
            new_text_splits.append('Investor')
        elif split.lower() in ['inst', 'inst.', 'institution']:
            new_text_splits.append('Institutional')
        elif split.lower() in ['cap', 'cap.']:
            new_text_splits.append('Capitalisation')
        elif split.lower() in ['adm', 'adm.']:
            new_text_splits.append('Admin')
        elif split.lower() in ['adv', 'adv.']:
            new_text_splits.append('Advantage')
        elif split.lower() in ['hdg', 'hgd', 'hdg.', 'hgd.', '(h)']:
            new_text_splits.append('Hedged')
        elif split.lower() in ['cl', 'cl.']:
            new_text_splits.append('Class')
        elif split.lower() in ['ser', 'ser.']:
            new_text_splits.append('Series')
        elif split.lower() in ['u.s.']:
            new_text_splits.append('US')
        elif split.lower() in ['nc', 'nc.']:
            new_text_splits.append('no trail')
        else:
            new_text_splits.append(split)
    
    new_text = ' '.join(new_text_splits)
    return new_text