codevise/pageflow

import $ from 'jquery';
import I18n from 'i18n-js';
import _ from 'underscore';

/**
 * Returns an array of translation keys based on the `prefixes`
 * option and the given `keyName`.
 *
 * @param {string} keyName
 *   Suffix to append to prefixes.
 *
 * @param {string[]} [options.prefixes]
 *   Array of translation key prefixes.
 *
 * @param {string} [options.fallbackPrefix]
 *   Optional additional prefix to form a model based translation
 *   key of the form
 *   `prefix.fallbackModelI18nKey.propertyName.keyName`.
 *
 * @param {string} [options.fallbackModelI18nKey]
 *   Required if `fallbackPrefix` option is present.
 *
 * @return {string[]}
 * @memberof i18nUtils
 * @since 12.0
 */
export function attributeTranslationKeys(attributeName, keyName, options) {
  var result = [];

  if (options.prefixes) {
    result = result.concat(_(options.prefixes).map(function(prefix) {
      return prefix + '.' + attributeName + '.' + keyName;
    }, this));
  }

  if (options && options.fallbackPrefix) {
    result.push(options.fallbackPrefix + '.' +
                options.fallbackModelI18nKey + '.' +
                attributeName);
  }

  return result;
}

/**
 * Takes the same parameters as {@link
 * #i18nutilsattributetranslationkeys attributeTranslationKeys}, but returns the first existing
 * translation.
 *
 * @return {string}
 * @memberof i18nUtils
 * @since 12.0
 */
export function attributeTranslation(attributeName, keyName, options) {
  return findTranslation(
    attributeTranslationKeys(attributeName, keyName, options)
  );
}

/**
 * Find the first key for which a translation exists and return the
 * translation.
 *
 * @param {string[]} keys
 *   Translation key candidates.
 *
 * @param {string} [options.defaultValue]
 *   Value to return if none of the keys has a translation. Is
 *   treated like an HTML translation if html flag is set.
 *
 * @param {boolean} [options.html]
 *   If true, also search for keys ending in '_html' and HTML-escape
 *   keys that do not end in 'html'
 *
 * @memberof i18nUtils
 * @return {string}
 */
export function findTranslation(keys, options) {
  options = options || {};

  if (options.html) {
    keys = translationKeysWithSuffix(keys, 'html');
  }

  return _.chain(keys).reverse().reduce(function(result, key) {
    var unescapedTranslation = I18n.t(key, _.extend({}, options, {defaultValue: result}));
    if (!options.html || key.match(/_html$/) || result == unescapedTranslation) {
      return unescapedTranslation;
    }
    else {
      return $('<div />').text(unescapedTranslation).html();
    }
  }, options.defaultValue).value();
}

/**
 * Return the first key for which a translation exists. Returns the
 * first if non of the keys has a translation.
 *
 * @param {string[]} keys
 * Translation key candidates.
 *
 * @memberof i18nUtils
 * @return {string}
 */
export function findKeyWithTranslation(keys) {
  var missing = '_not_translated';

  return _(keys).detect(function(key) {
    return I18n.t(key, {defaultValue: missing}) !== missing;
  }) || _.first(keys);
}

export function translationKeysWithSuffix(keys, suffix) {
  return _.chain(keys).map(function(key) {
    return [key + '_' + suffix, key];
  }).flatten().value();
}