<?php
/**
 * patI18n Module
 *
 * $Id$
 *
 * Modular translation interface
 *
 * @package wombat
 * @author gERD Schaufelberger <gerd@php-tools.net>
 * @package wombat
 * @subpackage nls
 */

/**
 * patI18n Module Wombat
 *
 * Translations are stored in table, use Wombat framework for table access
 *
 * @version 1.1.0
 * @package wombat
 */
class patI18n_Module_Wombat extends patI18n_Module
{
    /**
     * corrent language
     * @var string
     */
    protected $lang =   'C';

    /**
     * table access
     * @var WBDatasource_Table
     */
    protected  $table;

    /**
     * cached translation table
     * @var array
     */
    static $cache   =   array();

   /**
    * current config
    *
    * Options:
    *  - "clang" language representing C (usually en_GB, sometimes en_US)
    *  - "domain" sets the default text domain - if any
    *  - "domains" allows to use additional text domains
    *  - "fuzzy": "hide" (default) or "show" outdated translations
    *
    * @var array
    */
    protected $conf    =   array(
                                'clang'     =>  'en_GB',
                                'domain'    =>  null,
                                'domains'   =>  array(),
                                'fuzzy'     =>  'hide'
                            );

   /**
    * Switch to language
    *
    * @param string $string
    * @return booll true on success
    */
    public function setLocale(&$locale)
    {
        // check text domains
        if (!$this->conf['domain']) {
            WBClass::load('WBException_Argument');
            throw new WBException_Argument('Default domain is required, set config parameter "domain"', 1, __CLASS__);
        }

        // allow just five letter language codes 'de_DE' or 'en_GB'
        if (5 != strlen($locale)) {
            WBClass::load('WBException_Argument');
            throw new WBException_Argument('Locale must be five letter code like "en_GB" or "de_DE".', 2, __CLASS__);
        }

        // clear cache
        self::$cache    =   array();
        $this->lang     =   $locale;
        return true;
    }

    /**
     * get acutal text domain string
     *
     * validate selected domain string against available text domains
     *
     * @param string $domain
     * @return string
     */
    protected function resolveDomain($domain = null)
    {
        if (!$domain || $domain == $this->conf['domain']) {
            return $this->conf['domain'];
        }

        if (!in_array($domain, $this->conf['domains'])) {
            WBClass::load('WBException_Argument');
            throw new WBException_Argument('Invalid text domain "'. $domain .'" selected', 2, __CLASS__);
        }
        return $domain;
    }

   /**
    * Gettext interface
    *
    * @param string $string
    * @param string $domain
    * @return bool false to continue, true if translation is done
    */
    public function gettext(&$string, $domain = null)
    {
        $string =   trim($string);
        if (empty($string)) {
            return true;
        }

        $domain =   $this->resolveDomain($domain);
        if (!isset(self::$cache[$domain])) {
            $this->load($domain);
        }

        $md5    =   md5($string);
        if (!isset(self::$cache[$domain][$md5])) {
            return false;
        }


        // find actual translation
        if (!empty(self::$cache[$domain][$md5]['trans_' . $this->lang])) {
            $string =   self::$cache[$domain][$md5]['trans_' . $this->lang];
            return true;
        }

        // in case there is no translation, the origin text may have changed.
        $string =   self::$cache[$domain][$md5]['msg'];
        return false;
    }

    /**
     * load messages and translations from database
     *
     * Load all strings from text domain.and store them in cache
     *
     * @param string $domain
     */
    private function load($domain)
    {
        WBClass::load('WBCache');
        $cacheId    =   __CLASS__ . ':' . $domain  . ':' . $this->lang;
        self::$cache[$domain]   =   WBCache::get($cacheId);
        if (!empty(self::$cache[$domain])) {
            return;
        }

        self::$cache[$domain]   =   array();

        $this->initTable();

        $clause     =   array();
        $clause[]   =   array(
                            'field' =>  'domain',
                            'value' =>  $domain
                        );

        $options    =   array(
                            'column'    =>  array(
                                    $this->table->getIdentifier('nlsmsg'),
                                    'md5',
                                    'msg',
                                    'msg_org'
                                )
                        );
        // translation column
        if ('C' != $this->lang && $this->conf['clang'] != $this->lang) {

            // show or hide outdated translations
            if ('show' != $this->conf['fuzzy']) {
                $c      =   array();
                $c[]    =   array(
                                    'field'     =>  'changed_' . $this->lang,
                                    'valuetype' =>  'foreign',
                                    'foreign'   =>  'nlsmsg',
                                    'value'     =>  'changed',
                                    'relation'  =>  'ge'
                                );
                $c[]    =   array(
                                    'field'     =>  'changed_' . $this->lang,
                                    'value'     =>  '0000-00-00 00:00:00'
                                );
                $clause[]   =   array(
                                    'type'      =>  'complex',
                                    'bond'      =>  'or',
                                    'clause'    =>  $c
                                );
            }

            $options['column'][]    =   'trans_' . $this->lang;
        }

        $list   =   $this->table->get('nlsmsg', null, null, $clause, $options);
        foreach ($list as $l) {
            self::$cache[$domain][$l['md5']]    =   $l;
        }

        WBCache::set($cacheId, self::$cache[$domain], array('ttl' => 300));
    }

   /**
    * Gettext interface for plural versions
    *
    * @todo implement this
    * @param string $string
    * @param string $stringPlural
    * @param int $count
    * @param string $domain
    * @return bool false to continue, true if translation is done
    */
    public function ngettext(&$string, $stringPlural, $count, $domain = null)
    {
        // shortcut to avoid useless database queries
        if ($count <= 1) {
            return $this->gettext($string, $domain);
        }

        $domain =   $this->resolveDomain($domain);
        return false;
    }

    /**
     * Initialize table access
     *
     */
    protected function initTable()
    {
        if ($this->table) {
            return;
        }
        // Start table access, translation does not make any sense here, because we are translation! :-)
        $this->table    =   WBClass::create('WBDatasource_Table');
        $this->table->switchTranslation(false);
        $this->table->switchEventTrigger(false);
    }
}