symfony · clemens-tolboom · May 10, 2012 · stloyd · May 20, 2012
diff --git a/src/Symfony/Component/Translation/Dumper/PoFileDumper.php b/src/Symfony/Component/Translation/Dumper/PoFileDumper.php
@@ -12,6 +12,7 @@
 namespace Symfony\Component\Translation\Dumper;
 
 use Symfony\Component\Translation\MessageCatalogue;
+use Symfony\Component\Translation\Gettext;
 
 /**
  * PoFileDumper generates a gettext formatted string representation of a message catalogue.
@@ -23,18 +24,43 @@ class PoFileDumper extends FileDumper
     /**
      * {@inheritDoc}
      */
-    public function format(MessageCatalogue $messages, $domain = 'messages')
+    public function format(MessageCatalogue $catalogue, $domain = 'messages')
     {
         $output = '';
+        $messages = $catalogue->all();
+        $header = Gettext::getHeader($messages['messages']);
         $newLine = false;
-        foreach ($messages->all($domain) as $source => $target) {
+        if (!empty($header)) {
+            $output .= Gettext::headerToString($header);
+            $newLine = true;
+        }
+        Gettext::deleteHeader($messages['messages']);
+        $messages = $messages[$domain];
+        // Make plural form translations arrays
+        $this->extractSingulars($messages);
+        foreach ($messages as $source => $target) {
             if ($newLine) {
-              $output .= "\n";
+                $output .= "\n\n";
+            } else {
+                $newLine = true;
+            }
+            // Gettext PO files only understand non indexed rules or 'standard'
+            if (!is_array($target)) {
+                $output .= sprintf("msgid \"%s\"\n", $this->escape($source));
+                $output .= sprintf("msgstr \"%s\"", $this->escape($target));
             } else {
-              $newLine = true;
+                // ExtractSingular return 3 items so extract these.
+                list( $singularKey, $plural_key, $targets) = $target;
+                $output .= sprintf("msgid \"%s\"\n", $this->escape($source));
+                $output .= sprintf("msgid_plural \"%s\"\n", $this->escape($plural_key));
+                $targets = explode("|", $targets);
+                foreach ($targets as $index => $target) {
+                    if ($index>0) {
+                        $output .= "\n";
+                    }
+                    $output .= sprintf('msgstr[%d] "%s"', $index, $this->escape($target));
+                }
             }
-            $output .= sprintf('msgid "%s"'."\n", $this->escape($source));
-            $output .= sprintf('msgstr "%s"', $this->escape($target));
         }
 
         return $output;
@@ -52,4 +78,43 @@ private function escape($str)
     {
         return addcslashes($str, "\0..\37\42\134");
     }
+
+    /**
+     * Merges the singular and plurals back into 1 item.
+     *
+     * Gettext allows for a combination of messages being a singular and
+     * a plural form for the source.
+     *
+     * msgid "One sheep"
+     * msgid_plural "@count sheep"
+     * msgstr[0] "un mouton"
+     * msgstr[1] "@count moutons"
+     *
+     * By scanning $messages for "One sheep|@count sheep" we can recombine
+     * these string for Dumping.
+     *
+     * @param array $messages All plural forms are merged into the first occurence of a singular.
+     */
+    private function extractSingulars(array &$messages)
+    {
+        $messageBundles = array();
+        foreach ($messages as $key => $message) {
+            if (strpos($key, '|') !== FALSE) {
+                $messageBundles[] = $key;
+            }
+        }
+        foreach ($messageBundles as $bundle) {
+            list($singularKey, $pluralKey) = explode('|', $bundle, 2);
+            if (isset($messages[$singularKey])&&isset($messages[$pluralKey])) {
+                $messages[$singularKey] = array(
+                    $singularKey,
+                    $pluralKey,
+                    $messages[$pluralKey],
+                );
+                unset($messages[$pluralKey]);
+                unset($messages[$bundle]);
+            }
+        }
+    }
+
 }
diff --git a/src/Symfony/Component/Translation/Gettext.php b/src/Symfony/Component/Translation/Gettext.php
@@ -0,0 +1,205 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Translation;
+
+/**
+ * Provide for specific Gettext related helper functionality.
+ *
+ * @see http://www.gnu.org/software/gettext/manual/gettext.html#PO-Files
+ * @author Clemens Tolboom
+ * @copyright Clemens Tolboom clemens@build2be.com
+ */
+class Gettext
+{
+    /**
+     * Defines a key for managing a PO Header in our messages.
+     *
+     * Gettext files (.po .mo) can contain a header which needs to be managed.
+     * A Gettext file can have multiple domains into one file. This is called
+     * a message context or msgctxt.
+     *
+     * To provide for both header and context this class provides for
+     * some static functions to (help) process their values.
+     *
+     * @see GettextTest
+     * @see PoFileLoader
+     * @see PoFileLoaderTest
+     * @see PoFileDumper
+     * @see PoFileDumperTest
+     */
+    const HEADER_KEY = "__HEADER__";
+    const CONTEXT_KEY = "__CONTEXT__";
+
+    /**
+     * Merge key/value pair into Gettext compatible item.
+     *
+     * Each combination is into substring: "key: value \n".
+     *
+     * If any key found the values are preceded by empty msgid and msgstr
+     *
+     * @param array $header
+     * @return array|NULL A Gettext compatible string.
+     */
+    static public function headerToString(array $header)
+    {
+        $zipped = Gettext::zipHeader($header);
+        if (!empty($zipped)) {
+           $result = array(
+               'msgid ""',
+               'msgstr ""',
+               $zipped,
+           );
+
+           return implode("\n", $result);
+        }
+    }
+
+    /**
+     * Ordered list of Gettext header keys
+     *
+     * TODO: this list is probably incomplete
+     *
+     * @return array Ordered list of Gettext keys
+     */
+    static public function headerKeys() {
+        return array(
+            'Project-Id-Version',
+            'POT-Creation-Date',
+            'PO-Revision-Date',
+            'Last-Translator',
+            'Language-Team',
+            'MIME-Version',
+            'Content-Type',
+            'Content-Transfer-Encoding',
+            'Plural-Forms'
+        );
+    }
+
+    static public function emptyHeader() {
+        return array_fill_keys(Gettext::headerKeys(), "");
+    }
+
+    /**
+     * Retrieve PO Header from messages.
+     *
+     * @param array $messages
+     * @return array containing key/value pair|empty array.
+     */
+    static public function getHeader(array &$messages)
+    {
+        if (isset($messages[Gettext::HEADER_KEY])) {
+           return Gettext::unzipHeader($messages[Gettext::HEADER_KEY]);
+        }
+
+        return array();
+    }
+
+    /**
+     * Adds or overwrite a header to the messages.
+     *
+     * @param array $messages
+     * @param array $header
+     */
+    static public function addHeader(array &$messages, array $header)
+    {
+        $messages[Gettext::HEADER_KEY] = Gettext::zipHeader($header);
+    }
+
+    /**
+     * Deletes a header from the messages if exists.
+     *
+     * @param array $messages
+     */
+    static public function deleteHeader(array &$messages) {
+        if (isset($messages[Gettext::HEADER_KEY])) {
+            unset($messages[Gettext::HEADER_KEY]);
+        }
+    }
+
+    /**
+     * Add context to the messages.
+     *
+     * Gettext supports for multiple context (domains) in one PO|MO file.
+     * By injecting these into the translated messages we can post process.
+     *
+     * @param array $messages
+     * @param type  $context
+     */
+    static public function addContext(array &$messages, $context) {
+        if (!isset($messages[Gettext::CONTEXT_KEY])) {
+            $messages[Gettext::CONTEXT_KEY] = '';
+        }
+        $contexts = array_flip(explode('|', $messages[Gettext::CONTEXT_KEY]));
+        $contexts[$context] = $context;
+        unset($contexts['']);
+        $messages[Gettext::CONTEXT_KEY] = implode('|', array_keys($contexts));
+    }
+
+    static public function deleteContext(array &$messages) {
+        unset($messages[Gettext::CONTEXT_KEY]);
+    }
+
+    static public function getContext(array &$messages) {
+        if (isset($messages[Gettext::CONTEXT_KEY])) {
+            return explode('|', $messages[Gettext::CONTEXT_KEY]);
+        }
+
+        return array();
+    }
+
+    /**
+     * Parses a Gettext header string into a key/value pairs.
+     *
+     * @param $header
+     *   The Gettext header.
+     * @return array
+     *   Array with the key/value pair
+     */
+    static private function unzipHeader($header)
+    {
+        $result = array();
+        $lines = explode("\n", $header);
+        foreach ($lines as $line) {
+            $cleaned = trim($line);
+            $cleaned = preg_replace(array('/^\"/','/\\\n\"$/'), '', $cleaned);
+            if (strpos($cleaned, ':') > 0) {
+                list($key, $value) = explode(':', $cleaned, 2);
+                $result[trim($key)] = trim($value);
+            }
+        }
+
+        return $result;
+    }
+
+    /**
+     * Zips header into a Gettext formatted string.
+     *
+     * The returned value is what msgstr would contain when used by the header
+     * in a Gettext file.
+     *
+     * @param array $header
+     * @return string
+     *
+     * @see unzipHeader().
+     * @see fixtures/full.po
+     */
+    static private function zipHeader(array $header)
+    {
+        $lines = array();
+        foreach ($header as $key => $value) {
+            $lines[] = '"' . $key . ": " . $value . '\n"';
+        }
+
+        return implode("\n", $lines);
+    }
+
+}