designtopack/public/kirby/src/Toolkit/I18n.php
2024-07-10 16:10:33 +02:00

333 lines
8.3 KiB
PHP

<?php
namespace Kirby\Toolkit;
use Closure;
use NumberFormatter;
/**
* Localization class, roughly inspired by VueI18n
*
* @package Kirby Toolkit
* @author Bastian Allgeier <bastian@getkirby.com>
* @link https://getkirby.com
* @copyright Bastian Allgeier
* @license https://opensource.org/licenses/MIT
*/
class I18n
{
/**
* Custom loader function
*/
public static Closure|null $load = null;
/**
* Current locale
*/
public static string|Closure|null $locale = 'en';
/**
* All registered translations
*/
public static array $translations = [];
/**
* The fallback locale or a list of fallback locales
*/
public static string|array|Closure|null $fallback = ['en'];
/**
* Cache of `NumberFormatter` objects by locale
*/
protected static array $decimalsFormatters = [];
/**
* Returns the list of fallback locales
*/
public static function fallbacks(): array
{
if (is_callable(static::$fallback) === true) {
static::$fallback = (static::$fallback)();
}
if (is_array(static::$fallback) === true) {
return static::$fallback;
}
if (is_string(static::$fallback) === true) {
return A::wrap(static::$fallback);
}
return static::$fallback = ['en'];
}
/**
* Returns singular or plural depending on the given number
*
* @param bool $none If true, 'none' will be returned if the count is 0
*/
public static function form(int $count, bool $none = false): string
{
if ($none === true && $count === 0) {
return 'none';
}
return $count === 1 ? 'singular' : 'plural';
}
/**
* Formats a number
*/
public static function formatNumber(int|float $number, string $locale = null): string
{
$locale ??= static::locale();
$formatter = static::decimalNumberFormatter($locale);
$number = $formatter?->format($number) ?? $number;
return (string)$number;
}
/**
* Returns the current locale code
*/
public static function locale(): string
{
if (is_callable(static::$locale) === true) {
static::$locale = (static::$locale)();
}
if (is_string(static::$locale) === true) {
return static::$locale;
}
return static::$locale = 'en';
}
/**
* Translate by key and then replace
* placeholders in the text
*/
public static function template(
string $key,
string|array $fallback = null,
array|null $replace = null,
string|null $locale = null
): string {
if (is_array($fallback) === true) {
$replace = $fallback;
$fallback = null;
$locale = null;
}
$template = static::translate($key, $fallback, $locale);
return Str::template($template, $replace, ['fallback' => '-']);
}
/**
* Translates either a given i18n key from global translations
* or chooses correct entry from array of translations
* according to the currently set locale
*/
public static function translate(
string|array|null $key,
string|array $fallback = null,
string $locale = null
): string|array|Closure|null {
// use current locale if no specific is passed
$locale ??= static::locale();
// create shorter locale code, e.g. `es` for `es_ES` locale
$shortLocale = Str::before($locale, '_');
// There are two main use cases that we will treat separately:
// (1) with a string representing an i18n key to be looked up
// (2) an array with entries per locale
//
// Both with various ways of handling fallbacks, provided
// explicitly via the parameter and/or from global defaults.
// (1) string $key: look up i18n string from global translations
if (is_string($key) === true) {
// look up locale in global translations list,
if ($result = static::translation($locale)[$key] ?? null) {
return $result;
}
// prefer any direct provided $fallback
// over further fallback alternatives
if ($fallback !== null) {
if (is_array($fallback) === true) {
return static::translate($fallback, null, $locale);
}
return $fallback;
}
// last resort: try using the fallback locales
foreach (static::fallbacks() as $fallback) {
// skip locale if we have already tried to save performance
if ($locale === $fallback) {
continue;
}
if ($result = static::translation($fallback)[$key] ?? null) {
return $result;
}
}
return null;
}
// --------
// (2) array|null $key with entries per locale
// try entry for long and short locale
if ($result = $key[$locale] ?? null) {
return $result;
}
if ($result = $key[$shortLocale] ?? null) {
return $result;
}
// if the array as a global wildcard entry,
// use this one as i18n key and try to resolve
// this via part (1) of this method
if ($wildcard = $key['*'] ?? null) {
if ($result = static::translate($wildcard, $wildcard, $locale)) {
return $result;
}
}
// if the $fallback parameter is an array, we can assume
// that it's also an array with entries per locale:
// check with long and short locale if we find a matching entry
if ($result = $fallback[$locale] ?? null) {
return $result;
}
if ($result = $fallback[$shortLocale] ?? null) {
return $result;
}
// all options for long/short actual locale have been exhausted,
// revert to the list of fallback locales and try with each of them
foreach (static::fallbacks() as $locale) {
// first on the original input
if ($result = $key[$locale] ?? null) {
return $result;
}
// then on the fallback
if ($result = $fallback[$locale] ?? null) {
return $result;
}
}
// if a string was provided as fallback, use that one
if (is_string($fallback) === true) {
return $fallback;
}
// otherwise the first array element of the input
// or the first array element of the fallback
if (is_array($key) === true) {
return reset($key);
}
if (is_array($fallback) === true) {
return reset($fallback);
}
return null;
}
/**
* Returns the current or any other translation
* by locale. If the translation does not exist
* yet, the loader will try to load it, if defined.
*/
public static function translation(string $locale = null): array
{
$locale ??= static::locale();
if ($translation = static::$translations[$locale] ?? null) {
return $translation;
}
if (static::$load instanceof Closure) {
return static::$translations[$locale] = (static::$load)($locale);
}
// try to use language code, e.g. `es` when locale is `es_ES`
if ($translation = static::$translations[Str::before($locale, '_')] ?? null) {
return $translation;
}
return static::$translations[$locale] = [];
}
/**
* Returns all loaded or defined translations
*/
public static function translations(): array
{
return static::$translations;
}
/**
* Returns (and creates) a decimal number formatter for a given locale
*/
protected static function decimalNumberFormatter(string $locale): NumberFormatter|null
{
if ($formatter = static::$decimalsFormatters[$locale] ?? null) {
return $formatter;
}
if (
extension_loaded('intl') !== true ||
class_exists('NumberFormatter') !== true
) {
return null; // @codeCoverageIgnore
}
return static::$decimalsFormatters[$locale] = new NumberFormatter($locale, NumberFormatter::DECIMAL);
}
/**
* Translates amounts
*
* Translation definition options:
* - Translation is a simple string: `{{ count }}` gets replaced in the template
* - Translation is an array with a value for each count: Chooses the correct template and
* replaces `{{ count }}` in the template; if no specific template for the input count is
* defined, the template that is defined last in the translation array is used
* - Translation is a callback with a `$count` argument: Returns the callback return value
*
* @param bool $formatNumber If set to `false`, the count is not formatted
*/
public static function translateCount(
string $key,
int $count,
string $locale = null,
bool $formatNumber = true
) {
$locale ??= static::locale();
$translation = static::translate($key, null, $locale);
if ($translation === null) {
return null;
}
if ($translation instanceof Closure) {
return $translation($count);
}
$message = match (true) {
is_string($translation) => $translation,
isset($translation[$count]) => $translation[$count],
default => end($translation)
};
if ($formatNumber === true) {
$count = static::formatNumber($count, $locale);
}
return Str::template($message, compact('count'));
}
}