web/wp-includes/pomo/translations.php
changeset 136 bde1974c263b
child 194 32102edaa81b
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/web/wp-includes/pomo/translations.php	Wed Feb 03 15:37:20 2010 +0000
@@ -0,0 +1,251 @@
+<?php
+/**
+ * Class for a set of entries for translation and their associated headers
+ *
+ * @version $Id: translations.php 291 2009-10-21 05:46:08Z nbachiyski $
+ * @package pomo
+ * @subpackage translations
+ */
+
+require_once dirname(__FILE__) . '/entry.php';
+
+if ( !class_exists( 'Translations' ) ):
+class Translations {
+	var $entries = array();
+	var $headers = array();
+
+	/**
+	 * Add entry to the PO structure
+	 *
+	 * @param object &$entry
+	 * @return bool true on success, false if the entry doesn't have a key
+	 */
+	function add_entry($entry) {
+		if (is_array($entry)) {
+			$entry = new Translation_Entry($entry);
+		}
+		$key = $entry->key();
+		if (false === $key) return false;
+		$this->entries[$key] = &$entry;
+		return true;
+	}
+
+	/**
+	 * Sets $header PO header to $value
+	 *
+	 * If the header already exists, it will be overwritten
+	 *
+	 * TODO: this should be out of this class, it is gettext specific
+	 *
+	 * @param string $header header name, without trailing :
+	 * @param string $value header value, without trailing \n
+	 */
+	function set_header($header, $value) {
+		$this->headers[$header] = $value;
+	}
+
+	function set_headers(&$headers) {
+		foreach($headers as $header => $value) {
+			$this->set_header($header, $value);
+		}
+	}
+
+	function get_header($header) {
+		return isset($this->headers[$header])? $this->headers[$header] : false;
+	}
+
+	function translate_entry(&$entry) {
+		$key = $entry->key();
+		return isset($this->entries[$key])? $this->entries[$key] : false;
+	}
+
+	function translate($singular, $context=null) {
+		$entry = new Translation_Entry(array('singular' => $singular, 'context' => $context));
+		$translated = $this->translate_entry($entry);
+		return ($translated && !empty($translated->translations))? $translated->translations[0] : $singular;
+	}
+
+	/**
+	 * Given the number of items, returns the 0-based index of the plural form to use
+	 *
+	 * Here, in the base Translations class, the commong logic for English is implmented:
+	 * 	0 if there is one element, 1 otherwise
+	 *
+	 * This function should be overrided by the sub-classes. For example MO/PO can derive the logic
+	 * from their headers.
+	 *
+	 * @param integer $count number of items
+	 */
+	function select_plural_form($count) {
+		return 1 == $count? 0 : 1;
+	}
+
+	function get_plural_forms_count() {
+		return 2;
+	}
+
+	function translate_plural($singular, $plural, $count, $context = null) {
+		$entry = new Translation_Entry(array('singular' => $singular, 'plural' => $plural, 'context' => $context));
+		$translated = $this->translate_entry($entry);
+		$index = $this->select_plural_form($count);
+		$total_plural_forms = $this->get_plural_forms_count();
+		if ($translated && 0 <= $index && $index < $total_plural_forms &&
+				is_array($translated->translations) &&
+				isset($translated->translations[$index]))
+			return $translated->translations[$index];
+		else
+			return 1 == $count? $singular : $plural;
+	}
+
+	/**
+	 * Merge $other in the current object.
+	 *
+	 * @param Object &$other Another Translation object, whose translations will be merged in this one
+	 * @return void
+	 **/
+	function merge_with(&$other) {
+		$this->entries = array_merge($this->entries, $other->entries);
+	}
+}
+
+class Gettext_Translations extends Translations {
+	/**
+	 * The gettext implmentation of select_plural_form.
+	 *
+	 * It lives in this class, because there are more than one descendand, which will use it and
+	 * they can't share it effectively.
+	 *
+	 */
+	function gettext_select_plural_form($count) {
+		if (!isset($this->_gettext_select_plural_form) || is_null($this->_gettext_select_plural_form)) {
+			list( $nplurals, $expression ) = $this->nplurals_and_expression_from_header($this->get_header('Plural-Forms'));
+			$this->_nplurals = $nplurals;
+			$this->_gettext_select_plural_form = $this->make_plural_form_function($nplurals, $expression);
+		}
+		return call_user_func($this->_gettext_select_plural_form, $count);
+	}
+	
+	function nplurals_and_expression_from_header($header) {
+		if (preg_match('/^\s*nplurals\s*=\s*(\d+)\s*;\s+plural\s*=\s*(.+)$/', $header, $matches)) {
+			$nplurals = (int)$matches[1];
+			$expression = trim($this->parenthesize_plural_exression($matches[2]));
+			return array($nplurals, $expression);
+		} else {
+			return array(2, 'n != 1');
+		}
+	}
+
+	/**
+	 * Makes a function, which will return the right translation index, according to the
+	 * plural forms header
+	 */
+	function make_plural_form_function($nplurals, $expression) {
+		$expression = str_replace('n', '$n', $expression);
+		$func_body = "
+			\$index = (int)($expression);
+			return (\$index < $nplurals)? \$index : $nplurals - 1;";
+		return create_function('$n', $func_body);
+	}
+
+	/**
+	 * Adds parantheses to the inner parts of ternary operators in
+	 * plural expressions, because PHP evaluates ternary oerators from left to right
+	 * 
+	 * @param string $expression the expression without parentheses
+	 * @return string the expression with parentheses added
+	 */
+	function parenthesize_plural_exression($expression) {
+		$expression .= ';';
+		$res = '';
+		$depth = 0;
+		for ($i = 0; $i < strlen($expression); ++$i) {
+			$char = $expression[$i];
+			switch ($char) {
+				case '?':
+					$res .= ' ? (';
+					$depth++;
+					break;
+				case ':':
+					$res .= ') : (';
+					break;
+				case ';':
+					$res .= str_repeat(')', $depth) . ';';
+					$depth= 0;
+					break;
+				default:
+					$res .= $char;
+			}
+		}
+		return rtrim($res, ';');
+	}
+	
+	function make_headers($translation) {
+		$headers = array();
+		// sometimes \ns are used instead of real new lines
+		$translation = str_replace('\n', "\n", $translation);
+		$lines = explode("\n", $translation);
+		foreach($lines as $line) {
+			$parts = explode(':', $line, 2);
+			if (!isset($parts[1])) continue;
+			$headers[trim($parts[0])] = trim($parts[1]);
+		}
+		return $headers;
+	}
+	
+	function set_header($header, $value) {
+		parent::set_header($header, $value);
+		if ('Plural-Forms' == $header) {
+			list( $nplurals, $expression ) = $this->nplurals_and_expression_from_header($this->get_header('Plural-Forms'));
+			$this->_nplurals = $nplurals;
+			$this->_gettext_select_plural_form = $this->make_plural_form_function($nplurals, $expression);
+		}
+	}
+}
+endif;
+
+if ( !class_exists( 'NOOP_Translations' ) ):
+/**
+ * Provides the same interface as Translations, but doesn't do anything
+ */
+class NOOP_Translations {
+	var $entries = array();
+	var $headers = array();
+	
+	function add_entry($entry) {
+		return true;
+	}
+
+	function set_header($header, $value) {
+	}
+
+	function set_headers(&$headers) {
+	}
+
+	function get_header($header) {
+		return false;
+	}
+
+	function translate_entry(&$entry) {
+		return false;
+	}
+
+	function translate($singular, $context=null) {
+		return $singular;
+	}
+
+	function select_plural_form($count) {
+		return 1 == $count? 0 : 1;
+	}
+
+	function get_plural_forms_count() {
+		return 2;
+	}
+
+	function translate_plural($singular, $plural, $count, $context = null) {
+			return 1 == $count? $singular : $plural;
+	}
+
+	function merge_with(&$other) {
+	}
+}
+endif;