#!/usr/bin/env node

const fs = require("fs");
const path = require("path");

const argv = require("yargs").argv;

export default () => {
  const i18nDocumentUpdate = (lng: string) => {
    /* next-i18next.config.js */
    const workingDir = path.resolve(process.cwd());
    const i18nPath = path.resolve(workingDir, "next-i18next.config.js");

    if (!fs.existsSync(i18nPath)) {
      return;
    }

    const i18nData = fs.readFileSync(i18nPath, {
      encoding: "utf8",
      flag: "r",
    });

    const regExpLiteral = "locales:(.+)+";

    const result = i18nData.match(regExpLiteral);

    if (result[1].search(lng) < 0) {
      throw new Error(`${lng.toUpperCase()} not available`);
    }

    let updatedData = i18nData.replace(
      /defaultLocale: '.*'/,
      `defaultLocale: '${lng}'`
    );

    updatedData = updatedData.replace(
      /fallbackLng: '.*'/,
      `fallbackLng: '${lng}'`
    );

    fs.writeFileSync(i18nPath, updatedData);
  };

  const init = () => {
    if (!argv.defaultLanguage) return;
    let lng = argv.defaultLanguage;

    try {
      i18nDocumentUpdate(lng);
      console.log(
        "\x1b[32m%s\x1b[0m",
        `\n✓ Set as the default language option ${lng.toUpperCase()}.\n`
      );
      console.log("\x1b[33m%s\x1b[0m", "Project Zero - Akinon\n");
    } catch (err) {
      const typedError = err as Error;

      console.log(
        "\n\x1b[31m%s\x1b[0m",
        `${
          typedError.message
            ? typedError.message + "\n"
            : "Something went wrong.\n"
        }`
      );
    }
  };

  init();
};