"""adapted from https://github.com/keithito/tacotron"""

import re

_letters_and_numbers_re = re.compile(
    r"((?:[a-zA-Z]+[0-9]|[0-9]+[a-zA-Z])[a-zA-Z0-9']*)", re.IGNORECASE
)

_hardware_re = re.compile(
    "([0-9]+(?:[.,][0-9]+)?)(?:\s?)(tb|gb|mb|kb|ghz|mhz|khz|hz|mm)", re.IGNORECASE
)
_hardware_key = {
    "tb": "terabyte",
    "gb": "gigabyte",
    "mb": "megabyte",
    "kb": "kilobyte",
    "ghz": "gigahertz",
    "mhz": "megahertz",
    "khz": "kilohertz",
    "hz": "hertz",
    "mm": "millimeter",
    "cm": "centimeter",
    "km": "kilometer",
}

_dimension_re = re.compile(
    r"\b(\d+(?:[,.]\d+)?\s*[xX]\s*\d+(?:[,.]\d+)?\s*[xX]\s*\d+(?:[,.]\d+)?(?:in|inch|m)?)\b|\b(\d+(?:[,.]\d+)?\s*[xX]\s*\d+(?:[,.]\d+)?(?:in|inch|m)?)\b"
)
_dimension_key = {"m": "meter", "in": "inch", "inch": "inch"}


def _expand_letters_and_numbers(m):
    text = re.split(r"(\d+)", m.group(0))

    # remove trailing space
    if text[-1] == "":
        text = text[:-1]
    elif text[0] == "":
        text = text[1:]

    # if not like 1920s, or AK47's , 20th, 1st, 2nd, 3rd, etc...
    if text[-1] in ("'s", "s", "th", "nd", "st", "rd") and text[-2].isdigit():
        text[-2] = text[-2] + text[-1]
        text = text[:-1]

    # for combining digits 2 by 2
    new_text = []
    for i in range(len(text)):
        string = text[i]
        if string.isdigit() and len(string) < 5:
            # heuristics
            if len(string) > 2 and string[-2] == "0":
                if string[-1] == "0":
                    string = [string]
                else:
                    string = [string[:-3], string[-2], string[-1]]
            elif len(string) % 2 == 0:
                string = [string[i : i + 2] for i in range(0, len(string), 2)]
            elif len(string) > 2:
                string = [string[0]] + [
                    string[i : i + 2] for i in range(1, len(string), 2)
                ]
            new_text.extend(string)
        else:
            new_text.append(string)

    text = new_text
    text = " ".join(text)
    return text


def _expand_hardware(m):
    quantity, measure = m.groups(0)
    measure = _hardware_key[measure.lower()]
    if measure[-1] != "z" and float(quantity.replace(",", "")) > 1:
        return "{} {}s".format(quantity, measure)
    return "{} {}".format(quantity, measure)


def _expand_dimension(m):
    text = "".join([x for x in m.groups(0) if x != 0])
    text = text.replace(" x ", " by ")
    text = text.replace("x", " by ")
    if text.endswith(tuple(_dimension_key.keys())):
        if text[-2].isdigit():
            text = "{} {}".format(text[:-1], _dimension_key[text[-1:]])
        elif text[-3].isdigit():
            text = "{} {}".format(text[:-2], _dimension_key[text[-2:]])
    return text


def normalize_letters_and_numbers(text):
    text = re.sub(_hardware_re, _expand_hardware, text)
    text = re.sub(_dimension_re, _expand_dimension, text)
    text = re.sub(_letters_and_numbers_re, _expand_letters_and_numbers, text)
    return text