localizePlural function

String localizePlural(Object? modifier, String key, ITranslations translations, { String? locale, })

Returns the translated version for the plural modifier. After getting the version, substring %d will be replaced with the modifier.

Note: This will try to get the most specific plural modifier. For example, .two is more specific than .many.

If no applicable modifier can be found, it will default to the unversioned string. For example, this: "a".zero("b").four("c:") will default to "a" for 1, 2, 3, or more than 5 elements.

The modifier should usually be an integer. But in case it's not, it will be converted into an integer. The rules are:

1. If the modifier is an int, its absolute value will be used. Note: absolute value means a negative value will become positive.

2. If the modifier is a double, its absolute value will be used, like so:

• 1.0 will be 1.
• Values below 1.0 will become 0.
• Values larger than 1.0 will be rounded up.

3. Strings will be converted to integer or if that fails to a double. Conversion is done like so:

• First, it will discard other chars than numbers, dot and the minus sign, by converting them to spaces.
• Then it will convert to int using int.tryParse.
• Then it will convert to double using double.tryParse.
• If all fails, it will be zero.

4. Other objects will be converted to a string (using the toString method), and then the above rules will apply.

Implementation

String localizePlural(
  Object? modifier,
  String key,
  ITranslations translations, {
  String? locale,
}) {
  int modifierInt = convertToIntegerModifier(modifier);

  locale = locale?.toLowerCase();

  Map<String?, String> versions = localizeAllVersions(key, translations, locale: locale);

  String? text;

  /// For plural(0), returns the version 0, otherwise the version the version
  /// 0-1, otherwise the version many, otherwise the unversioned.
  if (modifierInt == 0)
    text = versions["0"] ?? versions["F"] ?? versions["M"] ?? versions[null];

  /// For plural(1), returns the version 1, otherwise the version the version
  /// 0-1, otherwise the version the version 1-many, otherwise the unversioned.
  else if (modifierInt == 1)
    text = versions["1"] ?? versions["F"] ?? versions["R"] ?? versions[null];

  /// For plural(2), returns the version 2, otherwise the version 2-3-4,
  /// otherwise the version many/1-many, otherwise the unversioned.
  else if (modifierInt == 2)
    text = versions["2"] ?? versions["C"] ?? versions["M"] ?? versions["R"] ?? versions[null];

  /// For plural(3), returns the version 3, otherwise the version 2-3-4,
  /// otherwise the version many/1-many, otherwise the unversioned.
  else if (modifierInt == 3)
    text = versions["3"] ?? versions["C"] ?? versions["M"] ?? versions["R"] ?? versions[null];

  /// For plural(4), returns the version 4, otherwise the version 2-3-4,
  /// otherwise the version many/1-many, otherwise the unversioned.
  else if (modifierInt == 4)
    text = versions["4"] ?? versions["C"] ?? versions["M"] ?? versions["R"] ?? versions[null];

  /// For plural(5), returns the version 5, otherwise the version many/1-many,
  /// otherwise the unversioned.
  else if (modifierInt == 5)
    text = versions["5"] ?? versions["M"] ?? versions["R"] ?? versions[null];

  /// For plural(6), returns the version 6, otherwise the version many/1-many,
  /// otherwise the unversioned.
  else if (modifierInt == 6)
    text = versions["6"] ?? versions["M"] ?? versions["R"] ?? versions[null];

  /// For plural(10), returns the version 10, otherwise the version many/1-many,
  /// For plural(10), returns the version 10, otherwise the version many/1-many,
  /// otherwise the unversioned.
  else if (modifierInt == 10)
    text = versions["T"] ?? versions["M"] ?? versions["R"] ?? versions[null];

  /// For plural(<0 or >2), returns the version many/1-many,
  /// otherwise the unversioned.
  else
    text = versions[modifierInt.toString()] ?? versions["M"] ?? versions["R"] ?? versions[null];

  // ---

  if (text == null)
    throw TranslationsException("No version found "
        "(modifier: $modifierInt, "
        "key: '$key', "
        "locale: '${_effectiveLocale(locale)}').");

  text = text.replaceAll("%d", modifierInt.toString());

  return text;
}