# SPDX-License-Identifier: AGPL-3.0-or-later
# lint: pylint
"""Yahoo Search (Web)

Languages are supported by mapping the language to a domain.  If domain is not
found in :py:obj:`lang2domain` URL ``<lang>.search.yahoo.com`` is used.

"""

from urllib.parse import (
    unquote,
    urlencode,
)
from lxml import html

from searx.utils import (
    eval_xpath_getindex,
    eval_xpath_list,
    extract_text,
    match_language,
)

# about
about = {
    "website": 'https://search.yahoo.com/',
    "wikidata_id": None,
    "official_api_documentation": 'https://developer.yahoo.com/api/',
    "use_official_api": False,
    "require_api_key": False,
    "results": 'HTML',
}

# engine dependent config
categories = ['general']
paging = True
time_range_support = True
supported_languages_url = 'https://search.yahoo.com/preferences/languages'
"""Supported languages are read from Yahoo preference page."""

time_range_dict = {
    'day': ('1d', 'd'),
    'week': ('1w', 'w'),
    'month': ('1m', 'm'),
}

language_aliases = {
    'zh-HK': 'zh_chs',
    'zh-CN': 'zh_chs',  # dead since 2015 / routed to hk.search.yahoo.com
    'zh-TW': 'zh_cht',
}

lang2domain = {
    'zh_chs' : 'hk.search.yahoo.com',
    'zh_cht' : 'tw.search.yahoo.com',
    'en'     : 'search.yahoo.com',

    'bg'     : 'search.yahoo.com',
    'cs'     : 'search.yahoo.com',
    'da'     : 'search.yahoo.com',
    'el'     : 'search.yahoo.com',
    'et'     : 'search.yahoo.com',
    'he'     : 'search.yahoo.com',
    'hr'     : 'search.yahoo.com',
    'ja'     : 'search.yahoo.com',
    'ko'     : 'search.yahoo.com',
    'sk'     : 'search.yahoo.com',
    'sl'     : 'search.yahoo.com',

}
"""Map language to domain"""

def _get_language(params):

    lang = language_aliases.get(params['language'])
    if lang is None:
        lang = match_language(
            params['language'], supported_languages, language_aliases
        )
    lang = lang.split('-')[0]
    logger.debug("params['language']: %s --> %s" , params['language'], lang)
    return lang

def request(query, params):
    """build request"""
    offset = (params['pageno'] - 1) * 7 + 1
    lang  =  _get_language(params)
    age, btf = time_range_dict.get(
        params['time_range'], ('', ''))

    args = urlencode({
        'p' : query,
        'ei' : 'UTF-8',
        'fl' : 1,
        'vl' : 'lang_' + lang,
        'btf' : btf,
        'fr2' : 'time',
        'age' : age,
        'b' : offset,
        'xargs' :0
    })

    domain = lang2domain.get(lang, '%s.search.yahoo.com' % lang)
    params['url'] = 'https://%s/search?%s' % (domain, args)
    return params

def parse_url(url_string):
    """remove yahoo-specific tracking-url"""

    endings = ['/RS', '/RK']
    endpositions = []
    start = url_string.find('http', url_string.find('/RU=') + 1)

    for ending in endings:
        endpos = url_string.rfind(ending)
        if endpos > -1:
            endpositions.append(endpos)

    if start == 0 or len(endpositions) == 0:
        return url_string

    end = min(endpositions)
    return unquote(url_string[start:end])

def response(resp):
    """parse response"""

    results = []
    dom = html.fromstring(resp.text)

    # parse results
    for result in eval_xpath_list(dom, '//div[contains(@class,"algo-sr")]'):
        url = eval_xpath_getindex(result, './/h3/a/@href', 0, default=None)
        if url is None:
            continue
        url = parse_url(url)

        title = eval_xpath_getindex(result, './/h3/a', 0, default=None)
        if title is None:
            continue
        offset = len(extract_text(title.xpath('span')))
        title = extract_text(title)[offset:]

        content = eval_xpath_getindex(
            result, './/div[contains(@class, "compText")]', 0, default=''
        )
        if content:
            content = extract_text(content)

        # append result
        results.append({
            'url': url,
            'title': title,
            'content': content
        })

    for suggestion in eval_xpath_list(dom, '//div[contains(@class, "AlsoTry")]//table//a'):
        # append suggestion
        results.append({'suggestion': extract_text(suggestion)})

    return results


# get supported languages from their site
def _fetch_supported_languages(resp):
    supported_languages = []
    dom = html.fromstring(resp.text)
    offset = len('lang_')

    for val in eval_xpath_list(dom, '//div[contains(@class, "lang-item")]/input/@value'):
        supported_languages.append( val[offset:] )

    return supported_languages