framework/i18n/MessageFormatter.php
<?php
/**
* @link https://www.yiiframework.com/
* @copyright Copyright (c) 2008 Yii Software LLC
* @license https://www.yiiframework.com/license/
*/
namespace yii\i18n;
use Yii;
use yii\base\Component;
use yii\base\NotSupportedException;
/**
* MessageFormatter allows formatting messages via [ICU message format](https://unicode-org.github.io/icu/userguide/format_parse/messages/).
*
* This class enhances the message formatter class provided by the PHP intl extension.
*
* The following enhancements are provided:
*
* - It accepts named arguments and mixed numeric and named arguments.
* - Issues no error when an insufficient number of arguments have been provided. Instead, the placeholders will not be
* substituted.
* - Fixes PHP 5.5 weird placeholder replacement in case no arguments are provided at all (https://bugs.php.net/bug.php?id=65920).
* - Offers limited support for message formatting in case PHP intl extension is not installed.
* However it is highly recommended that you install [PHP intl extension](https://www.php.net/manual/en/book.intl.php) if you want
* to use MessageFormatter features.
*
* The fallback implementation only supports the following message formats:
* - plural formatting for english ('one' and 'other' selectors)
* - select format
* - simple parameters
* - integer number parameters
*
* The fallback implementation does NOT support the ['apostrophe-friendly' syntax](https://www.php.net/manual/en/messageformatter.formatmessage.php).
* Also messages that are working with the fallback implementation are not necessarily compatible with the
* PHP intl MessageFormatter so do not rely on the fallback if you are able to install intl extension somehow.
*
* @property-read string $errorCode Code of the last error.
* @property-read string $errorMessage Description of the last error.
*
* @author Alexander Makarov <sam@rmcreative.ru>
* @author Carsten Brandt <mail@cebe.cc>
* @since 2.0
*/
class MessageFormatter extends Component
{
private $_errorCode = 0;
private $_errorMessage = '';
/**
* Get the error code from the last operation.
* @link https://www.php.net/manual/en/messageformatter.geterrorcode.php
* @return string Code of the last error.
*/
public function getErrorCode()
{
return $this->_errorCode;
}
/**
* Get the error text from the last operation.
* @link https://www.php.net/manual/en/messageformatter.geterrormessage.php
* @return string Description of the last error.
*/
public function getErrorMessage()
{
return $this->_errorMessage;
}
/**
* Formats a message via [ICU message format](https://unicode-org.github.io/icu/userguide/format_parse/messages/).
*
* It uses the PHP intl extension's [MessageFormatter](https://www.php.net/manual/en/class.messageformatter.php)
* and works around some issues.
* If PHP intl is not installed a fallback will be used that supports a subset of the ICU message format.
*
* @param string $pattern The pattern string to insert parameters into.
* @param array $params The array of name value pairs to insert into the format string.
* @param string $language The locale to use for formatting locale-dependent parts
* @return string|false The formatted pattern string or `false` if an error occurred
*/
public function format($pattern, $params, $language)
{
$this->_errorCode = 0;
$this->_errorMessage = '';
if ($params === []) {
return $pattern;
}
if (!class_exists('MessageFormatter', false)) {
return $this->fallbackFormat($pattern, $params, $language);
}
// replace named arguments (https://github.com/yiisoft/yii2/issues/9678)
$newParams = [];
$pattern = $this->replaceNamedArguments($pattern, $params, $newParams);
$params = $newParams;
try {
$formatter = new \MessageFormatter($language, $pattern);
if ($formatter === null) {
// formatter may be null in PHP 5.x
$this->_errorCode = intl_get_error_code();
$this->_errorMessage = 'Message pattern is invalid: ' . intl_get_error_message();
return false;
}
} catch (\IntlException $e) {
// IntlException is thrown since PHP 7
$this->_errorCode = $e->getCode();
$this->_errorMessage = 'Message pattern is invalid: ' . $e->getMessage();
return false;
} catch (\Exception $e) {
// Exception is thrown by HHVM
$this->_errorCode = $e->getCode();
$this->_errorMessage = 'Message pattern is invalid: ' . $e->getMessage();
return false;
}
$result = $formatter->format($params);
if ($result === false) {
$this->_errorCode = $formatter->getErrorCode();
$this->_errorMessage = $formatter->getErrorMessage();
return false;
}
return $result;
}
/**
* Parses an input string according to an [ICU message format](https://unicode-org.github.io/icu/userguide/format_parse/messages/) pattern.
*
* It uses the PHP intl extension's [MessageFormatter::parse()](https://www.php.net/manual/en/messageformatter.parsemessage.php)
* and adds support for named arguments.
* Usage of this method requires PHP intl extension to be installed.
*
* @param string $pattern The pattern to use for parsing the message.
* @param string $message The message to parse, conforming to the pattern.
* @param string $language The locale to use for formatting locale-dependent parts
* @return array|bool An array containing items extracted, or `FALSE` on error.
* @throws \yii\base\NotSupportedException when PHP intl extension is not installed.
*/
public function parse($pattern, $message, $language)
{
$this->_errorCode = 0;
$this->_errorMessage = '';
if (!class_exists('MessageFormatter', false)) {
throw new NotSupportedException('You have to install PHP intl extension to use this feature.');
}
// replace named arguments
if (($tokens = self::tokenizePattern($pattern)) === false) {
$this->_errorCode = -1;
$this->_errorMessage = 'Message pattern is invalid.';
return false;
}
$map = [];
foreach ($tokens as $i => $token) {
if (is_array($token)) {
$param = trim($token[0]);
if (!isset($map[$param])) {
$map[$param] = count($map);
}
$token[0] = $map[$param];
$tokens[$i] = '{' . implode(',', $token) . '}';
}
}
$pattern = implode('', $tokens);
$map = array_flip($map);
$formatter = new \MessageFormatter($language, $pattern);
if ($formatter === null) {
$this->_errorCode = -1;
$this->_errorMessage = 'Message pattern is invalid.';
return false;
}
$result = $formatter->parse($message);
if ($result === false) {
$this->_errorCode = $formatter->getErrorCode();
$this->_errorMessage = $formatter->getErrorMessage();
return false;
}
$values = [];
foreach ($result as $key => $value) {
$values[$map[$key]] = $value;
}
return $values;
}
/**
* Replace named placeholders with numeric placeholders and quote unused.
*
* @param string $pattern The pattern string to replace things into.
* @param array $givenParams The array of values to insert into the format string.
* @param array $resultingParams Modified array of parameters.
* @param array $map
* @return string The pattern string with placeholders replaced.
*/
private function replaceNamedArguments($pattern, $givenParams, &$resultingParams = [], &$map = [])
{
if (($tokens = self::tokenizePattern($pattern)) === false) {
return false;
}
foreach ($tokens as $i => $token) {
if (!is_array($token)) {
continue;
}
$param = trim($token[0]);
if (array_key_exists($param, $givenParams)) {
// if param is given, replace it with a number
if (!isset($map[$param])) {
$map[$param] = count($map);
// make sure only used params are passed to format method
$resultingParams[$map[$param]] = $givenParams[$param];
}
$token[0] = $map[$param];
$quote = '';
} else {
// quote unused token
$quote = "'";
}
$type = isset($token[1]) ? trim($token[1]) : 'none';
// replace plural and select format recursively
if ($type === 'plural' || $type === 'select') {
if (!isset($token[2])) {
return false;
}
if (($subtokens = self::tokenizePattern($token[2])) === false) {
return false;
}
$c = count($subtokens);
for ($k = 0; $k + 1 < $c; $k++) {
if (is_array($subtokens[$k]) || !is_array($subtokens[++$k])) {
return false;
}
$subpattern = $this->replaceNamedArguments(implode(',', $subtokens[$k]), $givenParams, $resultingParams, $map);
$subtokens[$k] = $quote . '{' . $quote . $subpattern . $quote . '}' . $quote;
}
$token[2] = implode('', $subtokens);
}
$tokens[$i] = $quote . '{' . $quote . implode(',', $token) . $quote . '}' . $quote;
}
return implode('', $tokens);
}
/**
* Fallback implementation for MessageFormatter::formatMessage.
* @param string $pattern The pattern string to insert things into.
* @param array $args The array of values to insert into the format string
* @param string $locale The locale to use for formatting locale-dependent parts
* @return false|string The formatted pattern string or `false` if an error occurred
*/
protected function fallbackFormat($pattern, $args, $locale)
{
if (($tokens = self::tokenizePattern($pattern)) === false) {
$this->_errorCode = -1;
$this->_errorMessage = 'Message pattern is invalid.';
return false;
}
foreach ($tokens as $i => $token) {
if (is_array($token)) {
if (($tokens[$i] = $this->parseToken($token, $args, $locale)) === false) {
$this->_errorCode = -1;
$this->_errorMessage = 'Message pattern is invalid.';
return false;
}
}
}
return implode('', $tokens);
}
/**
* Tokenizes a pattern by separating normal text from replaceable patterns.
* @param string $pattern patter to tokenize
* @return array|bool array of tokens or false on failure
*/
private static function tokenizePattern($pattern)
{
$charset = Yii::$app ? Yii::$app->charset : 'UTF-8';
$depth = 1;
if (($start = $pos = mb_strpos($pattern, '{', 0, $charset)) === false) {
return [$pattern];
}
$tokens = [mb_substr($pattern, 0, $pos, $charset)];
while (true) {
$open = mb_strpos($pattern, '{', $pos + 1, $charset);
$close = mb_strpos($pattern, '}', $pos + 1, $charset);
if ($open === false && $close === false) {
break;
}
if ($open === false) {
$open = mb_strlen($pattern, $charset);
}
if ($close > $open) {
$depth++;
$pos = $open;
} else {
$depth--;
$pos = $close;
}
if ($depth === 0) {
$tokens[] = explode(',', mb_substr($pattern, $start + 1, $pos - $start - 1, $charset), 3);
$start = $pos + 1;
$tokens[] = mb_substr($pattern, $start, $open - $start, $charset);
$start = $open;
}
if ($depth !== 0 && ($open === false || $close === false)) {
break;
}
}
if ($depth !== 0) {
return false;
}
return $tokens;
}
/**
* Parses a token.
* @param array $token the token to parse
* @param array $args arguments to replace
* @param string $locale the locale
* @return bool|string parsed token or false on failure
* @throws \yii\base\NotSupportedException when unsupported formatting is used.
*/
private function parseToken($token, $args, $locale)
{
// parsing pattern based on ICU grammar:
// https://unicode-org.github.io/icu-docs/#/icu4c/classMessageFormat.html
$charset = Yii::$app ? Yii::$app->charset : 'UTF-8';
$param = trim($token[0]);
if (isset($args[$param])) {
$arg = $args[$param];
} else {
return '{' . implode(',', $token) . '}';
}
$type = isset($token[1]) ? trim($token[1]) : 'none';
switch ($type) {
case 'date':
case 'time':
case 'spellout':
case 'ordinal':
case 'duration':
case 'choice':
case 'selectordinal':
throw new NotSupportedException("Message format '$type' is not supported. You have to install PHP intl extension to use this feature.");
case 'number':
$format = isset($token[2]) ? trim($token[2]) : null;
if (is_numeric($arg) && ($format === null || $format === 'integer')) {
$number = number_format($arg);
if ($format === null && ($pos = strpos($arg, '.')) !== false) {
// add decimals with unknown length
$number .= '.' . substr($arg, $pos + 1);
}
return $number;
}
throw new NotSupportedException("Message format 'number' is only supported for integer values. You have to install PHP intl extension to use this feature.");
case 'none':
return $arg;
case 'select':
/* https://unicode-org.github.io/icu-docs/#/icu4c/classicu_1_1SelectFormat.html
selectStyle = (selector '{' message '}')+
*/
if (!isset($token[2])) {
return false;
}
$select = self::tokenizePattern($token[2]);
$c = count($select);
$message = false;
for ($i = 0; $i + 1 < $c; $i++) {
if (is_array($select[$i]) || !is_array($select[$i + 1])) {
return false;
}
$selector = trim($select[$i++]);
if ($message === false && $selector === 'other' || $selector == $arg) {
$message = implode(',', $select[$i]);
}
}
if ($message !== false) {
return $this->fallbackFormat($message, $args, $locale);
}
break;
case 'plural':
/* https://unicode-org.github.io/icu-docs/#/icu4c/classicu_1_1PluralFormat.html
pluralStyle = [offsetValue] (selector '{' message '}')+
offsetValue = "offset:" number
selector = explicitValue | keyword
explicitValue = '=' number // adjacent, no white space in between
keyword = [^[[:Pattern_Syntax:][:Pattern_White_Space:]]]+
message: see MessageFormat
*/
if (!isset($token[2])) {
return false;
}
$plural = self::tokenizePattern($token[2]);
$c = count($plural);
$message = false;
$offset = 0;
for ($i = 0; $i + 1 < $c; $i++) {
if (is_array($plural[$i]) || !is_array($plural[$i + 1])) {
return false;
}
$selector = trim($plural[$i++]);
if ($i == 1 && strncmp($selector, 'offset:', 7) === 0) {
$offset = (int) trim(mb_substr($selector, 7, ($pos = mb_strpos(str_replace(["\n", "\r", "\t"], ' ', $selector), ' ', 7, $charset)) - 7, $charset));
$selector = trim(mb_substr($selector, $pos + 1, mb_strlen($selector, $charset), $charset));
}
if (
$message === false && $selector === 'other' ||
strncmp($selector, '=', 1) === 0 && (int) mb_substr($selector, 1, mb_strlen($selector, $charset), $charset) === $arg ||
$selector === 'one' && $arg - $offset == 1
) {
$message = implode(',', str_replace('#', $arg - $offset, $plural[$i]));
}
}
if ($message !== false) {
return $this->fallbackFormat($message, $args, $locale);
}
break;
}
return false;
}
}