/*
 This file is part of GNU Taler
 (C) 2022 Taler Systems S.A.

 GNU Taler is free software; you can redistribute it and/or modify it under the
 terms of the GNU General Public License as published by the Free Software
 Foundation; either version 3, or (at your option) any later version.

 GNU Taler is distributed in the hope that it will be useful, but WITHOUT ANY
 WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
 A PARTICULAR PURPOSE.  See the GNU General Public License for more details.

 You should have received a copy of the GNU General Public License along with
 GNU Taler; see the file COPYING.  If not, see <http://www.gnu.org/licenses/>
 */

/**
 *
 * @author Sebastian Javier Marchano (sebasjm)
 */

import { Fragment, h, VNode } from "preact";
import { useEffect, useState } from "preact/hooks";
import { useTranslationContext } from "@gnu-taler/web-util/browser";
import { strings as messages } from "../i18n/strings.js";

type LangsNames = {
  [P in keyof typeof messages]: string;
};

const names: LangsNames = {
  es: "Español [es]",
  en: "English [en]",
  fr: "Français [fr]",
  de: "Deutsch [de]",
  sv: "Svenska [sv]",
  it: "Italiano [it]",
};

function getLangName(s: keyof LangsNames | string): string {
  if (names[s]) return names[s];
  return String(s);
}

export function LangSelector(): VNode {
  const [updatingLang, setUpdatingLang] = useState(false);
  const { lang, changeLanguage } = useTranslationContext();
  const [hidden, setHidden] = useState(true);

  useEffect(() => {
    function bodyKeyPress(event: KeyboardEvent) {
      if (event.code === "Escape") setHidden(true);
    }
    function bodyOnClick(event: Event) {
      setHidden(true);
    }
    document.body.addEventListener("click", bodyOnClick);
    document.body.addEventListener("keydown", bodyKeyPress as any);
    return () => {
      document.body.removeEventListener("keydown", bodyKeyPress as any);
      document.body.removeEventListener("click", bodyOnClick);
    };
  }, []);
  return (
    <div>
      <div class="relative mt-2">
        <button type="button" class="relative w-full cursor-default rounded-md bg-white py-1.5 pl-3 pr-10 text-left text-gray-900 shadow-sm ring-1 ring-inset ring-gray-300 focus:outline-none focus:ring-2 focus:ring-indigo-600 sm:text-sm sm:leading-6" aria-haspopup="listbox" aria-expanded="true" aria-labelledby="listbox-label"
          onClick={() => {
            setHidden((h) => !h);
          }}>
          <span class="flex items-center">
            <img src="https://taler.net/images/languageicon.svg" alt="" class="h-5 w-5 flex-shrink-0 rounded-full" />
            <span class="ml-3 block truncate">{getLangName(lang)}</span>
          </span>
          <span class="pointer-events-none absolute inset-y-0 right-0 flex items-center pr-2">
            <svg class="h-5 w-5 text-gray-400" viewBox="0 0 20 20" fill="currentColor" aria-hidden="true">
              <path fill-rule="evenodd" d="M10 3a.75.75 0 01.55.24l3.25 3.5a.75.75 0 11-1.1 1.02L10 4.852 7.3 7.76a.75.75 0 01-1.1-1.02l3.25-3.5A.75.75 0 0110 3zm-3.76 9.2a.75.75 0 011.06.04l2.7 2.908 2.7-2.908a.75.75 0 111.1 1.02l-3.25 3.5a.75.75 0 01-1.1 0l-3.25-3.5a.75.75 0 01.04-1.06z" clip-rule="evenodd" />
            </svg>
          </span>
        </button>

        {!hidden &&
          <ul class="absolute z-10 mt-1 max-h-60 w-full overflow-auto rounded-md bg-white py-1 text-base shadow-lg ring-1 ring-black ring-opacity-5 focus:outline-none sm:text-sm" tabIndex={-1} role="listbox" aria-labelledby="listbox-label" aria-activedescendant="listbox-option-3">
            {Object.keys(messages)
              .filter((l) => l !== lang)
              .map((lang) => (
                <li class="text-gray-900 hover:bg-indigo-600 hover:text-white cursor-pointer relative select-none py-2 pl-3 pr-9" role="option"
                  onClick={() => {
                    changeLanguage(lang);
                    setUpdatingLang(false);
                    setHidden(true)
                  }}
                >
                  <span class="font-normal block truncate">{getLangName(lang)}</span>

                  <span class="text-indigo-600 absolute inset-y-0 right-0 flex items-center pr-4">
                    {/* <svg class="h-5 w-5" viewBox="0 0 20 20" fill="currentColor" aria-hidden="true">
                        <path fill-rule="evenodd" d="M16.704 4.153a.75.75 0 01.143 1.052l-8 10.5a.75.75 0 01-1.127.075l-4.5-4.5a.75.75 0 011.06-1.06l3.894 3.893 7.48-9.817a.75.75 0 011.05-.143z" clip-rule="evenodd" />
                      </svg> */}
                  </span>
                </li>
              ))}

          </ul>
        }

      </div>
    </div>
  );
}
