// Copyright (c) 2020-2021 Drew Lemmy
// This file is part of KristWeb 2 under GPL-3.0.
import { notification } from "antd";

import i18n from "@utils/i18n";
import JSON5 from "json5";

import { store } from "@app";
import { setImportedLang } from "@store/actions/SettingsActions";

import { getEnglishData, analyseLanguage } from "./analyseLangs";

import Debug from "debug";
const debug = Debug("kristweb:settings-import-json");

async function importLanguage(contents: string) {
  // Parse the imported language
  const resources = JSON5.parse(contents);

  // Update the language
  i18n.addResourceBundle("und", "translation", resources, true, true);
  i18n.changeLanguage("und");

  // Analyse the language to show on the settings page
  const en = await getEnglishData();
  const analysed = analyseLanguage("und", undefined, en.keys, resources);
  store.dispatch(setImportedLang({
    enKeyCount: en.keyCount,
    languages: [analysed]
  }));

  notification.success({
    message: "Translation successfully imported.",
    description: "Language will be reset to English on next reload."
  });
}

export function importJSON(files?: FileList | null): void {
  // Note that any errors emitted by this function are intentionally left
  // untranslated. This is left as a precaution in case i18n breaks entirely.
  if (!files?.[0]) return;
  const file = files[0];

  debug("importing file %s: %o", file.name, file);

  // Disallow non-JSON files
  if (file.type !== "application/json") {
    notification.error({ message: "Not a JSON file." });
    return;
  }

  // Read the file
  const reader = new FileReader();
  reader.readAsText(file, "UTF-8");
  reader.onload = e => {
    if (!e.target || !e.target.result) return;

    const contents = e.target.result.toString();
    debug("got file contents: %s", contents);

    importLanguage(contents)
      .catch(err => {
        console.error(err);
        if (err.name === "SyntaxError")
          return notification.error({ message: "Invalid JSON." });
        else
          return notification.error({ message: "Unknown error importing custom language." });
      });
  };
}