import re

from lxml import html, etree  # type: ignore

import http_pool


# Matches not only latin symbols,
# but also cyrillic alphabet, Chinese hyeroglyphics...
word_regex = re.compile(r'\w+')

# Get all <div>s with lyrics
lyrics_xpath = etree.XPath('//div[@id="lyrics-root"][1]/div[@data-lyrics-container="true"]')

# Get <br>s to add newlines after them for correct text parsing
br_xpath = etree.XPath('.//br')


def search(title: str, artist: str) -> tuple[str, str]:
    '''Searches for Genius lyrics using SearXNG + Yahoo
    and returns the first result as tuple(title, url)'''

    resp = http_pool.get().request(
        'GET',
        'https://searx.dc09.ru/search',
        fields={
            'q': artist + ' ' + title + ' site:genius.com',
            'engines': 'brave',
            'safesearch': '0',
            'format': 'json',
        },
    )

    result: dict[str, str] = resp.json()['results'][0]
    del resp

    return (result['title'], result['url'])


def raise_on_irrelevant_result(res_title: str, track_track: str, track_artist: str) -> None:
    '''Raises ValueError
    if no words from track title are present in search result track title
    and no words from artist name are present in search result artist name'''

    res_artist, res_track = res_title.lower().split(' \u2013 ', maxsplit=1)
    if not (
        any(
            word.group(0).lower() in res_artist
            for word in word_regex.finditer(track_artist)
        )
        and
        any(
            word.group(0).lower() in res_track
            for word in word_regex.finditer(track_track)
        )
    ):
        raise ValueError


def parse(url: str) -> str:
    '''Requests a lyrics page and parses with libxml2,
    leaving only text and line breaks'''

    resp = http_pool.get().request('GET', url)
    tree = html.document_fromstring(resp.data)
    divs = lyrics_xpath(tree)
    del resp, tree

    return '\n'.join(_parse_text(div) for div in divs).strip()


def _parse_text(elem: html.HtmlElement) -> str:

    for br in br_xpath(elem):
        br.tail = '\n' + (br.tail or '')

    return elem.text_content()