<?php
/* vim: set expandtab tabstop=4 shiftwidth=4 softtabstop=4: */

/**
 * Contains the Translation2_Container_mdb2 class
 *
 * PHP versions 4 and 5
 *
 * LICENSE: Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR "AS IS" AND ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE FREEBSD PROJECT OR CONTRIBUTORS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * @category  Internationalization
 * @package   Translation2
 * @author    Lorenzo Alberton <l.alberton@quipo.it>
 * @copyright 2004-2007 Lorenzo Alberton
 * @license   http://www.debian.org/misc/bsd.license  BSD License (3 Clause)
 * @version   CVS: $Id$
 * @link      http://pear.php.net/package/Translation2
 */

/**
 * require Translation2_Container class
 */
require_once 'Translation2/Container.php';

/**
 * Storage driver for fetching data from a database
 *
 * This storage driver can use all databases which are supported
 * by the PEAR::MDB2 abstraction layer to fetch data.
 *
 * @category  Internationalization
 * @package   Translation2
 * @author    Lorenzo Alberton <l.alberton@quipo.it>
 * @copyright 2004-2007 Lorenzo Alberton
 * @license   http://www.debian.org/misc/bsd.license  BSD License (3 Clause)
 * @version   CVS: $Id$
 * @link      http://pear.php.net/package/Translation2
 */
class Translation2_Container_mdb2 extends Translation2_Container
{
    // {{{ class vars

    /**
     * MDB2 object
     * @var object
     */
    var $db = null;

    /**
     * query counter
     * @var integer
     * @access private
     */
    var $_queries = 0;

    // }}}
    // {{{ init

    /**
     * Initialize the container
     *
     * @param string &$db Connection data or MDB2 object
     *
     * @return boolean|PEAR_Error object if something went wrong
     */
    function init(&$db)
    {
        $this->_setDefaultOptions();
        if (PEAR::isError($err = $this->_connect($db))) {
            return $err;
        }
        return true;
    }

    // }}}
    // {{{ _connect()

    /**
     * Connect to database by using the given DSN string
     *
     * @param mixed &$db DSN string | array | MDB2 object
     *
     * @return boolean|PEAR_Error on error
     * @access private
     */
    function _connect(&$db)
    {
        if (is_object($db) && is_a($db, 'MDB2_Driver_Common')) {
            $this->db = &$db;
        } elseif (is_string($db) || is_array($db)) {
            include_once 'MDB2.php';
            $this->db =& MDB2::connect($db);
        } elseif (is_object($db) && MDB2::isError($db)) {
            return PEAR::raiseError($db->getMessage(), $db->code);
        } else {
            return PEAR::raiseError('The given dsn was not valid in file '
                                    . __FILE__ . ' at line ' . __LINE__,
                                    TRANSLATION2_ERROR_CANNOT_CONNECT,
                                    PEAR_ERROR_RETURN);
        }

        if (PEAR::isError($this->db)) {
            return $this->db;
        }
        return true;
    }

    // }}}
    // {{{ _setDefaultOptions()

    /**
     * Set some default options
     *
     * @return void
     * @access private
     */
    function _setDefaultOptions()
    {
        $this->options['langs_avail_table'] = 'langs';
        $this->options['lang_id_col']       = 'id';
        $this->options['lang_name_col']     = 'name';
        $this->options['lang_meta_col']     = 'meta';
        $this->options['lang_errmsg_col']   = 'error_text';
        $this->options['lang_encoding_col'] = 'encoding';

        $this->options['strings_default_table'] = 'i18n';
        $this->options['strings_tables']        = array(); // 'lang_id' => 'table_name'
        $this->options['string_id_col']         = 'id';
        $this->options['string_page_id_col']    = 'page_id';
        $this->options['string_text_col']       = '%s'; // col_name if one table per lang is used,
                                                        // or a pattern (i.e. "tr_%s" => "tr_EN_US")
    }

    // }}}
    // {{{ setCharset()

    /**
     * Set charset used to read/store the translations
     *
     * @param string $charset character set (encoding)
     *
     * @return PEAR_Error on error
     */
    function setCharset($charset)
    {
        return $this->db->setCharset($charset);
    }

    // }}}
    // {{{ fetchLangs()

    /**
     * Fetch the available langs if they're not cached yet.
     *
     * @return PEAR_Error on error
     */
    function fetchLangs()
    {
        $query = sprintf('SELECT %s AS id, %s AS name, %s AS meta, %s AS error_text, %s AS encoding FROM %s',
            $this->db->quoteIdentifier($this->options['lang_id_col'], true),
            $this->db->quoteIdentifier($this->options['lang_name_col'], true),
            $this->db->quoteIdentifier($this->options['lang_meta_col'], true),
            $this->db->quoteIdentifier($this->options['lang_errmsg_col'], true),
            $this->db->quoteIdentifier($this->options['lang_encoding_col'], true),
            $this->db->quoteIdentifier($this->options['langs_avail_table'], true)
        );

        ++$this->_queries;
        $res = $this->db->queryAll($query, null, MDB2_FETCHMODE_ASSOC);
        if (PEAR::isError($res)) {
            return $res;
        }
        foreach ($res as $row) {
            $row = array_change_key_case($row, CASE_LOWER);
            $this->langs[$row['id']] = $row;
        }
    }

    // }}}
    // {{{ getPage()

    /**
     * Returns an array of the strings in the selected page
     *
     * @param string $pageID page/group ID
     * @param string $langID language ID
     *
     * @return array
     */
    function &getPage($pageID = null, $langID = null)
    {
        $langID   = $this->_getLangID($langID);
        if (PEAR::isError($langID)) {
            return $langID;
        }
        $lang_col = $this->_getLangCol($langID);
        $table    = $this->_getLangTable($langID);
        
        $query = sprintf('SELECT %s, %s FROM %s WHERE %s ',
             $this->db->quoteIdentifier($this->options['string_id_col'], true),
             $this->db->quoteIdentifier($lang_col, true),
             $this->db->quoteIdentifier($table, true),
             $this->db->quoteIdentifier($this->options['string_page_id_col'], true)
        );

        if (is_null($pageID)) {
            $query .= 'IS NULL';
        } else {
            $query .= ' = ' . $this->db->quote($pageID, 'text');
        }

        ++$this->_queries;
        $res = $this->db->query($query);
        if (PEAR::isError($res)) {
            return $res;
        }

        $strings = array();
        while (list($key, $value) = $res->fetchRow(MDB2_FETCHMODE_ORDERED)) {
            $strings[$key] = $value;
        }
        $res->free();
        return $strings;
    }

    // }}}
    // {{{ getOne()

    /**
     * Get a single item from the container
     *
     * @param string $stringID string ID
     * @param string $pageID   page/group ID
     * @param string $langID   language ID
     *
     * @return string
     */
    function getOne($stringID, $pageID = null, $langID = null)
    {
        $langID   = $this->_getLangID($langID);
        if (PEAR::isError($langID)) {
            return $langID;
        }
        $lang_col = $this->_getLangCol($langID);
        $table    = $this->_getLangTable($langID);

        $query = sprintf('SELECT %s FROM %s WHERE %s = %s AND %s',
             $this->db->quoteIdentifier($lang_col, true),
             $this->db->quoteIdentifier($table, true),
             $this->db->quoteIdentifier($this->options['string_id_col'], true),
             $this->db->quote($stringID, 'text'),
             $this->db->quoteIdentifier($this->options['string_page_id_col'], true)
        );

        if (is_null($pageID)) {
            $query .= ' IS NULL';
        } else {
            $query .= ' = ' . $this->db->quote($pageID, 'text');
        }
        
        ++$this->_queries;
        return $this->db->queryOne($query);
    }

    // }}}
    // {{{ getStringID()

    /**
     * Get the stringID for the given string
     *
     * @param string $stringID string ID
     * @param string $pageID   page/group ID
     *
     * @return string
     */
    function getStringID($stringID, $pageID = null)
    {
        $lang_col = $this->_getLangCol($this->currentLang['id']);
        $table = $this->_getLangTable($this->currentLang['id']);
        $query = sprintf('SELECT %s FROM %s WHERE %s = %s AND %s',
             $this->db->quoteIdentifier($this->options['string_id_col'], true),
             $this->db->quoteIdentifier($table, true),
             $this->db->quoteIdentifier($lang_col, true),
             $this->db->quote($string, 'text'),
             $this->db->quoteIdentifier($this->options['string_page_id_col'], true)
        );
        if (is_null($pageID)) {
            $query .= ' IS NULL';
        } else {
            $query .= ' = ' . $this->db->quote($pageID, 'text');
        }
        ++$this->_queries;
        return $this->db->queryOne($query);
    }

    // }}}
    // {{{ _getLangTable()

    /**
     * Get the table a language is stored in
     *
     * @param string $langID language ID
     *
     * @return string table $langID is stored in
     * @access private
     */
    function _getLangTable($langID)
    {
        if (isset($this->options['strings_tables'][$langID])) {
            return $this->options['strings_tables'][$langID];
        }
        return str_replace('%s', $langID, $this->options['strings_default_table']);
    }

    // }}}
    // {{{ _getLangCol()

    /**
     * Get the column a language's string is stored in
     *
     * @param string $langID language ID
     *
     * @return string column $langID is stored in
     * @access private
     */
    function _getLangCol($langID)
    {
        static $cols;
        if (!isset($cols[$langID])) {
            if (isset($this->options['string_text_col']) &&
                !empty($this->options['string_text_col'])) {
                $cols[$langID] = str_replace('%s', $langID, $this->options['string_text_col']);
            } else {
                $cols[$langID] = $langID;
            }
        }
        return $cols[$langID];
    }

    // }}}
}
?>