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 114 2009-05-11 17:30:38Z nbachiyski $
   6  * @package pomo
   7  * @subpackage translations
   8  */
   9
  10 require_once dirname(__FILE__) . '/entry.php';
  11
  12 class Translations {
  13         var $entries = array();
  14         var $headers = array();
  15
  16         /**
  17          * Add entry to the PO structure
  18          *
  19          * @param object &$entry
  20          * @return bool true on success, false if the entry doesn't have a key
  21          */
  22         function add_entry($entry) {
  23                 if (is_array($entry)) {
  24                         $entry = new Translation_Entry($entry);
  25                 }
  26                 $key = $entry->key();
  27                 if (false === $key) return false;
  28                 $this->entries[$key] = $entry;
  29                 return true;
  30         }
  31
  32         /**
  33          * Sets $header PO header to $value
  34          *
  35          * If the header already exists, it will be overwritten
  36          *
  37          * TODO: this should be out of this class, it is gettext specific
  38          *
  39          * @param string $header header name, without trailing :
  40          * @param string $value header value, without trailing \n
  41          */
  42         function set_header($header, $value) {
  43                 $this->headers[$header] = $value;
  44         }
  45
  46         function set_headers(&$headers) {
  47                 foreach($headers as $header => $value) {
  48                         $this->set_header($header, $value);
  49                 }
  50         }
  51
  52         function get_header($header) {
  53                 return isset($this->headers[$header])? $this->headers[$header] : false;
  54         }
  55
  56         function translate_entry(&$entry) {
  57                 $key = $entry->key();
  58                 return isset($this->entries[$key])? $this->entries[$key] : false;
  59         }
  60
  61         function translate($singular, $context=null) {
  62                 $entry = new Translation_Entry(array('singular' => $singular, 'context' => $context));
  63                 $translated = $this->translate_entry($entry);
  64                 return ($translated && !empty($translated->translations))? $translated->translations[0] : $singular;
  65         }
  66
  67         /**
  68          * Given the number of items, returns the 0-based index of the plural form to use
  69          *
  70          * Here, in the base Translations class, the commong logic for English is implmented:
  71          *      0 if there is one element, 1 otherwise
  72          *
  73          * This function should be overrided by the sub-classes. For example MO/PO can derive the logic
  74          * from their headers.
  75          *
  76          * @param integer $count number of items
  77          */
  78         function select_plural_form($count) {
  79                 return 1 == $count? 0 : 1;
  80         }
  81
  82         function get_plural_forms_count() {
  83                 return 2;
  84         }
  85
  86         function translate_plural($singular, $plural, $count, $context = null) {
  87                 $entry = new Translation_Entry(array('singular' => $singular, 'plural' => $plural, 'context' => $context));
  88                 $translated = $this->translate_entry($entry);
  89                 $index = $this->select_plural_form($count);
  90                 $total_plural_forms = $this->get_plural_forms_count();
  91                 if ($translated && 0 <= $index && $index < $total_plural_forms &&
  92                                 is_array($translated->translations) &&
  93                                 isset($translated->translations[$index]))
  94                         return $translated->translations[$index];
  95                 else
  96                         return 1 == $count? $singular : $plural;
  97         }
  98
  99         /**
 100          * Merge $other in the current object.
 101          *
 102          * @param Object &$other Another Translation object, whose translations will be merged in this one
 103          * @return void
 104          **/
 105         function merge_with(&$other) {
 106                 $this->entries = array_merge($this->entries, $other->entries);
 107         }
 108 }
 109
 110 class Gettext_Translations extends Translations {
 111         /**
 112          * The gettext implmentation of select_plural_form.
 113          *
 114          * It lives in this class, because there are more than one descendand, which will use it and
 115          * they can't share it effectively.
 116          *
 117          */
 118         function gettext_select_plural_form($count) {
 119                 if (!isset($this->_gettext_select_plural_form) || is_null($this->_gettext_select_plural_form)) {
 120                         $plural_header = $this->get_header('Plural-Forms');
 121                         $this->_gettext_select_plural_form = $this->_make_gettext_select_plural_form($plural_header);
 122                 }
 123                 return call_user_func($this->_gettext_select_plural_form, $count);
 124         }
 125
 126         /**
 127          * Makes a function, which will return the right translation index, according to the
 128          * plural forms header
 129          */
 130         function _make_gettext_select_plural_form($plural_header) {
 131                 $res = create_function('$count', 'return 1 == $count? 0 : 1;');
 132                 if ($plural_header && (preg_match('/^\s*nplurals\s*=\s*(\d+)\s*;\s+plural\s*=\s*(.+)$/', $plural_header, $matches))) {
 133                         $nplurals = (int)$matches[1];
 134                         $this->_nplurals = $nplurals;
 135                         $plural_expr = trim($this->_parenthesize_plural_exression($matches[2]));
 136                         $plural_expr = str_replace('n', '$n', $plural_expr);
 137                         $func_body = "
 138                                 \$index = (int)($plural_expr);
 139                                 return (\$index < $nplurals)? \$index : $nplurals - 1;";
 140                         $res = create_function('$n', $func_body);
 141                 }
 142                 return $res;
 143         }
 144
 145         /**
 146          * Adds parantheses to the inner parts of ternary operators in
 147          * plural expressions, because PHP evaluates ternary oerators from left to right
 148          *
 149          * @param string $expression the expression without parentheses
 150          * @return string the expression with parentheses added
 151          */
 152         function _parenthesize_plural_exression($expression) {
 153                 $expression .= ';';
 154                 $res = '';
 155                 $depth = 0;
 156                 for ($i = 0; $i < strlen($expression); ++$i) {
 157                         $char = $expression[$i];
 158                         switch ($char) {
 159                                 case '?':
 160                                         $res .= ' ? (';
 161                                         $depth++;
 162                                         break;
 163                                 case ':':
 164                                         $res .= ') : (';
 165                                         break;
 166                                 case ';':
 167                                         $res .= str_repeat(')', $depth) . ';';
 168                                         $depth= 0;
 169                                         break;
 170                                 default:
 171                                         $res .= $char;
 172                         }
 173                 }
 174                 return rtrim($res, ';');
 175         }
 176
 177         function make_headers($translation) {
 178                 $headers = array();
 179                 // sometimes \ns are used instead of real new lines
 180                 $translation = str_replace('\n', "\n", $translation);
 181                 $lines = explode("\n", $translation);
 182                 foreach($lines as $line) {
 183                         $parts = explode(':', $line, 2);
 184                         if (!isset($parts[1])) continue;
 185                         $headers[trim($parts[0])] = trim($parts[1]);
 186                 }
 187                 return $headers;
 188         }
 189
 190         function set_header($header, $value) {
 191                 parent::set_header($header, $value);
 192                 if ('Plural-Forms' == $header)
 193                         $this->_gettext_select_plural_form = $this->_make_gettext_select_plural_form($value);
 194         }
 195
 196
 197 }
 198
 199 ?>