i18next/i18next

export function get() {
  return {
    debug: false,
    initImmediate: true,

    ns: ['translation'],
    defaultNS: ['translation'],
    fallbackLng: ['dev'],
    fallbackNS: false, // string or array of namespaces

    supportedLngs: false, // array with supported languages
    nonExplicitSupportedLngs: false,
    load: 'all', // | currentOnly | languageOnly
    preload: false, // array with preload languages

    simplifyPluralSuffix: true,
    keySeparator: '.',
    nsSeparator: ':',
    pluralSeparator: '_',
    contextSeparator: '_',

    partialBundledLanguages: false, // allow bundling certain languages that are not remotely fetched
    saveMissing: false, // enable to send missing values
    updateMissing: false, // enable to update default values if different from translated value (only useful on initial development, or when keeping code as source of truth)
    saveMissingTo: 'fallback', // 'current' || 'all'
    saveMissingPlurals: true, // will save all forms not only singular key
    missingKeyHandler: false, // function(lng, ns, key, fallbackValue) -> override if prefer on handling
    missingInterpolationHandler: false, // function(str, match)

    postProcess: false, // string or array of postProcessor names
    postProcessPassResolved: false, // pass resolved object into 'options.i18nResolved' for postprocessor
    returnNull: false, // allows null value as valid translation
    returnEmptyString: true, // allows empty string value as valid translation
    returnObjects: false,
    joinArrays: false, // or string to join array
    returnedObjectHandler: false, // function(key, value, options) triggered if key returns object but returnObjects is set to false
    parseMissingKeyHandler: false, // function(key) parsed a key that was not found in t() before returning
    appendNamespaceToMissingKey: false,
    appendNamespaceToCIMode: false,
    overloadTranslationOptionHandler: function handle(args) {
      let ret = {};
      if (typeof args[1] === 'object') ret = args[1];
      if (typeof args[1] === 'string') ret.defaultValue = args[1];
      if (typeof args[2] === 'string') ret.tDescription = args[2];
      if (typeof args[2] === 'object' || typeof args[3] === 'object') {
        const options = args[3] || args[2];
        Object.keys(options).forEach((key) => {
          ret[key] = options[key];
        });
      }
      return ret;
    },
    interpolation: {
      escapeValue: true,
      /** @type {import('i18next').FormatFunction} */
      format: (value) => value,
      prefix: '{{',
      suffix: '}}',
      formatSeparator: ',',
      // prefixEscaped: '{{',
      // suffixEscaped: '}}',
      // unescapeSuffix: '',
      unescapePrefix: '-',

      nestingPrefix: '$t(',
      nestingSuffix: ')',
      nestingOptionsSeparator: ',',
      // nestingPrefixEscaped: '$t(',
      // nestingSuffixEscaped: ')',
      // defaultVariables: undefined // object that can have values to interpolate on - extends passed in interpolation data
      maxReplaces: 1000, // max replaces to prevent endless loop
      skipOnVariables: true,
    },
  };
}

/* eslint no-param-reassign: 0 */
export function transformOptions(options) {
  // create namespace object if namespace is passed in as string
  if (typeof options.ns === 'string') options.ns = [options.ns];
  if (typeof options.fallbackLng === 'string') options.fallbackLng = [options.fallbackLng];
  if (typeof options.fallbackNS === 'string') options.fallbackNS = [options.fallbackNS];

  // extend supportedLngs with cimode
  if (options.supportedLngs && options.supportedLngs.indexOf('cimode') < 0) {
    options.supportedLngs = options.supportedLngs.concat(['cimode']);
  }

  return options;
}