wp-includes/pomo/translations.php

   1 <?php
   2 /**
   3  * Class for a set of entries for translation and their associated headers
   4  *
   5  * @version $Id: translations.php 590 2010-12-20 19:58:37Z nbachiyski $
   6  * @package pomo
   7  * @subpackage translations
   8  */
   9
  10 require_once dirname(__FILE__) . '/entry.php';
  11
  12 if ( !class_exists( 'Translations' ) ):
  13 class Translations {
  14         var $entries = array();
  15         var $headers = array();
  16
  17         /**
  18          * Add entry to the PO structure
  19          *
  20          * @param object &$entry
  21          * @return bool true on success, false if the entry doesn't have a key
  22          */
  23         function add_entry($entry) {
  24                 if (is_array($entry)) {
  25                         $entry = new Translation_Entry($entry);
  26                 }
  27                 $key = $entry->key();
  28                 if (false === $key) return false;
  29                 $this->entries[$key] = &$entry;
  30                 return true;
  31         }
  32
  33         function add_entry_or_merge($entry) {
  34                 if (is_array($entry)) {
  35                         $entry = new Translation_Entry($entry);
  36                 }
  37                 $key = $entry->key();
  38                 if (false === $key) return false;
  39                 if (isset($this->entries[$key]))
  40                         $this->entries[$key]->merge_with($entry);
  41                 else
  42                         $this->entries[$key] = &$entry;
  43                 return true;
  44         }
  45
  46         /**
  47          * Sets $header PO header to $value
  48          *
  49          * If the header already exists, it will be overwritten
  50          *
  51          * TODO: this should be out of this class, it is gettext specific
  52          *
  53          * @param string $header header name, without trailing :
  54          * @param string $value header value, without trailing \n
  55          */
  56         function set_header($header, $value) {
  57                 $this->headers[$header] = $value;
  58         }
  59
  60         function set_headers(&$headers) {
  61                 foreach($headers as $header => $value) {
  62                         $this->set_header($header, $value);
  63                 }
  64         }
  65
  66         function get_header($header) {
  67                 return isset($this->headers[$header])? $this->headers[$header] : false;
  68         }
  69
  70         function translate_entry(&$entry) {
  71                 $key = $entry->key();
  72                 return isset($this->entries[$key])? $this->entries[$key] : false;
  73         }
  74
  75         function translate($singular, $context=null) {
  76                 $entry = new Translation_Entry(array('singular' => $singular, 'context' => $context));
  77                 $translated = $this->translate_entry($entry);
  78                 return ($translated && !empty($translated->translations))? $translated->translations[0] : $singular;
  79         }
  80
  81         /**
  82          * Given the number of items, returns the 0-based index of the plural form to use
  83          *
  84          * Here, in the base Translations class, the common logic for English is implemented:
  85          *      0 if there is one element, 1 otherwise
  86          *
  87          * This function should be overrided by the sub-classes. For example MO/PO can derive the logic
  88          * from their headers.
  89          *
  90          * @param integer $count number of items
  91          */
  92         function select_plural_form($count) {
  93                 return 1 == $count? 0 : 1;
  94         }
  95
  96         function get_plural_forms_count() {
  97                 return 2;
  98         }
  99
 100         function translate_plural($singular, $plural, $count, $context = null) {
 101                 $entry = new Translation_Entry(array('singular' => $singular, 'plural' => $plural, 'context' => $context));
 102                 $translated = $this->translate_entry($entry);
 103                 $index = $this->select_plural_form($count);
 104                 $total_plural_forms = $this->get_plural_forms_count();
 105                 if ($translated && 0 <= $index && $index < $total_plural_forms &&
 106                                 is_array($translated->translations) &&
 107                                 isset($translated->translations[$index]))
 108                         return $translated->translations[$index];
 109                 else
 110                         return 1 == $count? $singular : $plural;
 111         }
 112
 113         /**
 114          * Merge $other in the current object.
 115          *
 116          * @param Object &$other Another Translation object, whose translations will be merged in this one
 117          * @return void
 118          **/
 119         function merge_with(&$other) {
 120                 foreach( $other->entries as $entry ) {
 121                         $this->entries[$entry->key()] = $entry;
 122                 }
 123         }
 124
 125         function merge_originals_with(&$other) {
 126                 foreach( $other->entries as $entry ) {
 127                         if ( !isset( $this->entries[$entry->key()] ) )
 128                                 $this->entries[$entry->key()] = $entry;
 129                         else
 130                                 $this->entries[$entry->key()]->merge_with($entry);
 131                 }
 132         }
 133 }
 134
 135 class Gettext_Translations extends Translations {
 136         /**
 137          * The gettext implmentation of select_plural_form.
 138          *
 139          * It lives in this class, because there are more than one descendand, which will use it and
 140          * they can't share it effectively.
 141          *
 142          */
 143         function gettext_select_plural_form($count) {
 144                 if (!isset($this->_gettext_select_plural_form) || is_null($this->_gettext_select_plural_form)) {
 145                         list( $nplurals, $expression ) = $this->nplurals_and_expression_from_header($this->get_header('Plural-Forms'));
 146                         $this->_nplurals = $nplurals;
 147                         $this->_gettext_select_plural_form = $this->make_plural_form_function($nplurals, $expression);
 148                 }
 149                 return call_user_func($this->_gettext_select_plural_form, $count);
 150         }
 151
 152         function nplurals_and_expression_from_header($header) {
 153                 if (preg_match('/^\s*nplurals\s*=\s*(\d+)\s*;\s+plural\s*=\s*(.+)$/', $header, $matches)) {
 154                         $nplurals = (int)$matches[1];
 155                         $expression = trim($this->parenthesize_plural_exression($matches[2]));
 156                         return array($nplurals, $expression);
 157                 } else {
 158                         return array(2, 'n != 1');
 159                 }
 160         }
 161
 162         /**
 163          * Makes a function, which will return the right translation index, according to the
 164          * plural forms header
 165          */
 166         function make_plural_form_function($nplurals, $expression) {
 167                 $expression = str_replace('n', '$n', $expression);
 168                 $func_body = "
 169                         \$index = (int)($expression);
 170                         return (\$index < $nplurals)? \$index : $nplurals - 1;";
 171                 return create_function('$n', $func_body);
 172         }
 173
 174         /**
 175          * Adds parantheses to the inner parts of ternary operators in
 176          * plural expressions, because PHP evaluates ternary oerators from left to right
 177          *
 178          * @param string $expression the expression without parentheses
 179          * @return string the expression with parentheses added
 180          */
 181         function parenthesize_plural_exression($expression) {
 182                 $expression .= ';';
 183                 $res = '';
 184                 $depth = 0;
 185                 for ($i = 0; $i < strlen($expression); ++$i) {
 186                         $char = $expression[$i];
 187                         switch ($char) {
 188                                 case '?':
 189                                         $res .= ' ? (';
 190                                         $depth++;
 191                                         break;
 192                                 case ':':
 193                                         $res .= ') : (';
 194                                         break;
 195                                 case ';':
 196                                         $res .= str_repeat(')', $depth) . ';';
 197                                         $depth= 0;
 198                                         break;
 199                                 default:
 200                                         $res .= $char;
 201                         }
 202                 }
 203                 return rtrim($res, ';');
 204         }
 205
 206         function make_headers($translation) {
 207                 $headers = array();
 208                 // sometimes \ns are used instead of real new lines
 209                 $translation = str_replace('\n', "\n", $translation);
 210                 $lines = explode("\n", $translation);
 211                 foreach($lines as $line) {
 212                         $parts = explode(':', $line, 2);
 213                         if (!isset($parts[1])) continue;
 214                         $headers[trim($parts[0])] = trim($parts[1]);
 215                 }
 216                 return $headers;
 217         }
 218
 219         function set_header($header, $value) {
 220                 parent::set_header($header, $value);
 221                 if ('Plural-Forms' == $header) {
 222                         list( $nplurals, $expression ) = $this->nplurals_and_expression_from_header($this->get_header('Plural-Forms'));
 223                         $this->_nplurals = $nplurals;
 224                         $this->_gettext_select_plural_form = $this->make_plural_form_function($nplurals, $expression);
 225                 }
 226         }
 227 }
 228 endif;
 229
 230 if ( !class_exists( 'NOOP_Translations' ) ):
 231 /**
 232  * Provides the same interface as Translations, but doesn't do anything
 233  */
 234 class NOOP_Translations {
 235         var $entries = array();
 236         var $headers = array();
 237
 238         function add_entry($entry) {
 239                 return true;
 240         }
 241
 242         function set_header($header, $value) {
 243         }
 244
 245         function set_headers(&$headers) {
 246         }
 247
 248         function get_header($header) {
 249                 return false;
 250         }
 251
 252         function translate_entry(&$entry) {
 253                 return false;
 254         }
 255
 256         function translate($singular, $context=null) {
 257                 return $singular;
 258         }
 259
 260         function select_plural_form($count) {
 261                 return 1 == $count? 0 : 1;
 262         }
 263
 264         function get_plural_forms_count() {
 265                 return 2;
 266         }
 267
 268         function translate_plural($singular, $plural, $count, $context = null) {
 269                         return 1 == $count? $singular : $plural;
 270         }
 271
 272         function merge_with(&$other) {
 273         }
 274 }
 275 endif;