<?php
/**
* @link http://www.yiiframework.com/
* @copyright Copyright (c) 2008 Yii Software LLC
* @license http://www.yiiframework.com/license/
*/
namespace yii\i18n;
use yii\base\Component;
use yii\base\NotSupportedException;
/**
* MessageFormatter enhances the message formatter class provided by PHP intl extension.
*
* The following enhancements are provided:
*
* - 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](http://php.net/manual/en/book.intl.php) if you want
* to use MessageFormatter features.
*
* FallbackMessageFormatter is a fallback implementation for the PHP intl MessageFormatter that is
* used in case PHP intl extension is not installed.
*
* Do not use this class directly. Use [[MessageFormatter]] instead, which will automatically detect
* installed version of PHP intl and use the fallback if it is not installed.
*
* It is highly recommended that you install [PHP intl extension](http://php.net/manual/en/book.intl.php) if you want to use
* MessageFormatter features.
*
* This implementation only supports to following message formats:
* - plural formatting for english
* - select format
* - simple parameters
*
* The pattern also does NOT support the ['apostrophe-friendly' syntax](http://www.php.net/manual/en/messageformatter.formatmessage.php).
*
* Messages that can be parsed are also not necessarily compatible with the ICU formatting method so do not expect messages that work without intl installed
* to work with intl
*
* @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 text from the last operation
* @link http://php.net/manual/en/messageformatter.geterrorcode.php
* @return string Description of the last error.
*/
public function getErrorCode()
{
return $this->_errorCode;
}
/**
* Get the error text from the last operation
* @link http://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.
*
* @link http://php.net/manual/en/messageformatter.formatmessage.php
* @param string $language The locale to use for formatting locale-dependent parts
* @param string $message The pattern string to insert things into.
* @param array $params The array of values to insert into the format string
* @return string|boolean The formatted pattern string or `FALSE` if an error occurred
*/
public function format($language, $message, $params)
{
$this->_errorCode = 0;
$this->_errorMessage = '';
if ($params === []) {
return $message;
}
if (!class_exists('MessageFormatter', false)) {
return $this->fallbackFormat($language, $message, $params);
}
if (version_compare(PHP_VERSION, '5.5.0', '< ')) {
$message = $this->replaceNamedArguments($message, $params);
$params = array_values($params);
}
$formatter = new \MessageFormatter($language, $message);
if ($formatter === null) {
$this->_errorMessage = "Unable to format message in language '$language'.";
return false;
}
$result = $formatter->format($params);
if ($result === false) {
$this->_errorCode = $formatter->getErrorCode();
$this->_errorMessage = $formatter->getErrorMessage();
return false;
} else {
return $result;
}
}
/**
* Parse input string according to a message pattern
*
* @link http://www.php.net/manual/en/messageformatter.parsemessage.php
* @param string $language The locale to use for formatting locale-dependent parts
* @param string $pattern The pattern with which to parse the message.
* @param array $message The message to parse, conforming to the pattern.
* @return string|boolean An array containing items extracted, or `FALSE` on error.
* @throws \yii\base\NotSupportedException when PHP intl extension is not installed.
*/
public function parse($language, $pattern, $message)
{
$this->_errorCode = 0;
$this->_errorMessage = '';
if (!class_exists('MessageFormatter', false)) {
throw new NotSupportedException('You have to install PHP intl extension to use this feature.');
}
// TODO try to support named args
// if (version_compare(PHP_VERSION, '5.5.0', '< ')) {
// $message = $this->replaceNamedArguments($message, $params);
// $params = array_values($params);
// }
$formatter = new \MessageFormatter($language, $pattern);
if ($formatter === null) {
$this->_errorMessage = "Unable to parse message in language '$language'.";
return false;
}
$result = $formatter->parse($message);
if ($result === false) {
$this->_errorCode = $formatter->getErrorCode();
$this->_errorMessage = $formatter->getErrorMessage();
return false;
} else {
return $result;
}
}
/**
* Replace named placeholders with numeric placeholders and quote unused.
*
* @param string $pattern The pattern string to replace things into.
* @param array $args The array of values to insert into the format string.
* @return string The pattern string with placeholders replaced.
*/
private static function replaceNamedArguments($pattern, $args)
{
$map = array_flip(array_keys($args));
// parsing pattern based on ICU grammar:
// http://icu-project.org/apiref/icu4c/classMessageFormat.html#details
$parts = explode('{', $pattern);
$c = count($parts);
$pattern = $parts[0];
$d = 0;
$stack = [];
for($i = 1; $i < $c; $i++) {
if (preg_match('~^(\s*)([\d\w]+)(\s*)([},])(\s*)(.*)$~us', $parts[$i], $matches)) {
// if we are not inside a plural or select this is a message
if (!isset($stack[$d]) || $stack[$d] != 'plural' & & $stack[$d] != 'select') {
$d++;
// replace normal arg if it is available
if (isset($map[$matches[2]])) {
$q = '';
$pattern .= '{' . $matches[1] . $map[$matches[2]] . $matches[3];
} else {
// quote unused args
$q = ($matches[4] == '}') ? "'" : "";
$pattern .= "$q{" . $matches[1] . $matches[2] . $matches[3];
}
$pattern .= ($term = $matches[4] . $q . $matches[5] . $matches[6]);
// store type of current level
$stack[$d] = ($matches[4] == ',') ? substr($matches[6], 0, 6) : 'none';
// if it's plural or select, the next bracket is NOT begin of a message then!
if ($stack[$d] == 'plural' || $stack[$d] == 'select') {
$i++;
$d -= substr_count($term, '}');
} else {
$d -= substr_count($term, '}');
continue;
}
}
}
$pattern .= '{' . $parts[$i];
$d += 1 - substr_count($parts[$i], '}');
}
return $pattern;
}
/**
* Fallback implementation for MessageFormatter::formatMessage
* @param string $language The locale to use for formatting locale-dependent parts
* @param string $message The pattern string to insert things into.
* @param array $params The array of values to insert into the format string
* @return string|boolean The formatted pattern string or `FALSE` if an error occurred
*/
protected function fallbackFormat($locale, $pattern, $args = [])
{
if (($tokens = $this->tokenizePattern($pattern)) === false) {
return false;
}
foreach($tokens as $i => $token) {
if (is_array($token)) {
if (($tokens[$i] = $this->parseToken($token, $args, $locale)) === false) {
return false;
}
}
}
return implode('', $tokens);
}
/**
* Tokenizes a pattern by separating normal text from replaceable patterns
* @param string $pattern patter to tokenize
* @return array|bool array of tokens or false on failure
*/
private function tokenizePattern($pattern)
{
$depth = 1;
if (($start = $pos = mb_strpos($pattern, '{')) === false) {
return [$pattern];
}
$tokens = [mb_substr($pattern, 0, $pos)];
while(true) {
$open = mb_strpos($pattern, '{', $pos + 1);
$close = mb_strpos($pattern, '}', $pos + 1);
if ($open === false & & $close === false) {
break;
}
if ($open === false) {
$open = mb_strlen($pattern);
}
if ($close > $open) {
$depth++;
$pos = $open;
} else {
$depth--;
$pos = $close;
}
if ($depth == 0) {
$tokens[] = explode(',', mb_substr($pattern, $start + 1, $pos - $start - 1), 3);
$start = $pos + 1;
$tokens[] = mb_substr($pattern, $start, $open - $start);
$start = $open;
}
}
if ($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)
{
$param = trim($token[0]);
if (isset($args[$param])) {
$arg = $args[$param];
} else {
return '{' . implode(',', $token) . '}';
}
$type = isset($token[1]) ? trim($token[1]) : 'none';
switch($type)
{
case 'number':
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 'none': return $arg;
case 'select':
/* http://icu-project.org/apiref/icu4c/classicu_1_1SelectFormat.html
selectStyle = (selector '{' message '}')+
*/
$select = static::tokenizePattern($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 $this->fallbackFormat($locale, $message, $args);
}
break;
case 'plural':
/* http://icu-project.org/apiref/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
*/
$plural = static::tokenizePattern($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 & & substr($selector, 0, 7) == 'offset:') {
$offset = (int) trim(mb_substr($selector, 7, ($pos = mb_strpos(str_replace(["\n", "\r", "\t"], ' ', $selector), ' ', 7)) - 7));
$selector = trim(mb_substr($selector, $pos + 1));
}
if ($message === false & & $selector == 'other' ||
$selector[0] == '=' & & (int) mb_substr($selector, 1) == $arg ||
$selector == 'zero' & & $arg - $offset == 0 ||
$selector == 'one' & & $arg - $offset == 1 ||
$selector == 'two' & & $arg - $offset == 2
) {
$message = implode(',', str_replace('#', $arg - $offset, $plural[$i]));
}
}
if ($message !== false) {
return $this->fallbackFormat($locale, $message, $args);
}
break;
}
return false;
}
}
