# SPDX-License-Identifier: AGPL-3.0-or-later
"""
Arch Linux Wiki
~~~~~~~~~~~~~~~

This implementation does not use a official API: Mediawiki provides API, but
Arch Wiki blocks access to it.

"""

from urllib.parse import urlencode, urljoin, urlparse

import babel
import lxml

from searx.enginelib.traits import EngineTraits
from searx.locales import language_tag
from searx.utils import (
    eval_xpath_getindex,
    eval_xpath_list,
    extract_text,
    searxng_useragent,
)

about = {
    "website": "https://wiki.archlinux.org/",
    "wikidata_id": "Q101445877",
    "official_api_documentation": None,
    "use_official_api": False,
    "require_api_key": False,
    "results": "HTML",
}

# engine dependent config
categories = ["it", "software wikis"]
paging = True
main_wiki = "wiki.archlinux.org"


def request(query, params):

    sxng_lang = params["searxng_locale"].split("-")[0]
    netloc: str = traits.custom["wiki_netloc"].get(sxng_lang, main_wiki)  # type: ignore
    title: str = traits.custom["title"].get(sxng_lang, "Special:Search")  # type: ignore
    base_url = "https://" + netloc + "/index.php?"
    offset = (params["pageno"] - 1) * 20

    if netloc == main_wiki:
        eng_lang: str = traits.get_language(sxng_lang, "English")  # type: ignore
        query += " (" + eng_lang + ")"
        # wiki.archlinux.org is protected by anubis
        # - https://github.com/searxng/searxng/issues/4646#issuecomment-2817848019
        params["headers"]["User-Agent"] = searxng_useragent()
    elif netloc == "wiki.archlinuxcn.org":
        base_url = "https://" + netloc + "/wzh/index.php?"

    args = {
        "search": query,
        "title": title,
        "limit": 20,
        "offset": offset,
        "profile": "default",
    }

    params["url"] = base_url + urlencode(args)
    return params


def response(resp):

    results = []
    dom = lxml.html.fromstring(resp.text)  # type: ignore

    # get the base URL for the language in which request was made
    sxng_lang = resp.search_params["searxng_locale"].split("-")[0]
    netloc: str = traits.custom["wiki_netloc"].get(sxng_lang, main_wiki)  # type: ignore
    base_url = "https://" + netloc + "/index.php?"

    for result in eval_xpath_list(dom, '//ul[@class="mw-search-results"]/li'):
        link = eval_xpath_getindex(result, './/div[@class="mw-search-result-heading"]/a', 0)
        content = extract_text(result.xpath('.//div[@class="searchresult"]'))
        results.append(
            {
                "url": urljoin(base_url, link.get("href")),  # type: ignore
                "title": extract_text(link),
                "content": content,
            }
        )

    return results


def fetch_traits(engine_traits: EngineTraits):
    """Fetch languages from Archlinux-Wiki.  The location of the Wiki address of a
    language is mapped in a :py:obj:`custom field
    <searx.enginelib.traits.EngineTraits.custom>` (``wiki_netloc``).  Depending
    on the location, the ``title`` argument in the request is translated.

    .. code:: python

       "custom": {
         "wiki_netloc": {
           "de": "wiki.archlinux.de",
            # ...
           "zh": "wiki.archlinuxcn.org"
         }
         "title": {
           "de": "Spezial:Suche",
            # ...
           "zh": "Special:\u641c\u7d22"
         },
       },

    """
    # pylint: disable=import-outside-toplevel

    from searx.network import get  # see https://github.com/searxng/searxng/issues/762

    engine_traits.custom["wiki_netloc"] = {}
    engine_traits.custom["title"] = {}

    title_map = {
        "de": "Spezial:Suche",
        "fa": "ویژه:جستجو",
        "ja": "特別:検索",
        "zh": "Special:搜索",
    }

    resp = get("https://wiki.archlinux.org/", timeout=5)
    if not resp.ok:
        raise RuntimeError("Response from Arch Linux Wiki is not OK.")

    dom = lxml.html.fromstring(resp.text)  # type: ignore
    for a in eval_xpath_list(dom, "//a[@class='interlanguage-link-target']"):
        sxng_tag = language_tag(babel.Locale.parse(a.get("lang"), sep="-"))
        # zh_Hans --> zh
        sxng_tag = sxng_tag.split("_")[0]

        netloc = urlparse(a.get("href")).netloc
        if netloc != "wiki.archlinux.org":
            title = title_map.get(sxng_tag)
            if not title:
                print("ERROR: title tag from %s (%s) is unknown" % (netloc, sxng_tag))
                continue
            engine_traits.custom["wiki_netloc"][sxng_tag] = netloc
            engine_traits.custom["title"][sxng_tag] = title  # type: ignore

        eng_tag = extract_text(eval_xpath_list(a, ".//span"))
        engine_traits.languages[sxng_tag] = eng_tag  # type: ignore

    engine_traits.languages["en"] = "English"