<?php

/**

 * Zend Framework

 *

 * LICENSE

 *

 * This source file is subject to the new BSD license that is bundled

 * with this package in the file LICENSE.txt.

 * It is also available through the world-wide-web at this URL:

 * http://framework.zend.com/license/new-bsd

 * If you did not receive a copy of the license and are unable to

 * obtain it through the world-wide-web, please send an email

 * to license@zend.com so we can send you a copy immediately.

 *

 * @category   Zend

 * @package    Zend_Application

 * @subpackage Resource

 * @copyright  Copyright (c) 2005-2010 Zend Technologies USA Inc. (http://www.zend.com)

 * @license    http://framework.zend.com/license/new-bsd     New BSD License

 * @version    $Id: Multidb.php 22546 2010-07-10 15:18:12Z freak $

 */

require_once 'Zend/Application/Resource/ResourceAbstract.php';

require_once 'Zend/Db/Table.php';

/**

 */

/**

 * Cache Manager resource

 *

 * Example configuration:

 * <pre>

 *   resources.multidb.defaultMetadataCache = "database"

 *

 *   resources.multidb.db1.adapter = "pdo_mysql"

 *   resources.multidb.db1.host = "localhost"

 *   resources.multidb.db1.username = "webuser"

 *   resources.multidb.db1.password = "XXXX"

 *   resources.multidb.db1.dbname = "db1"

 *   resources.multidb.db1.default = true

 *

 *   resources.multidb.db2.adapter = "pdo_pgsql"

 *   resources.multidb.db2.host = "example.com"

 *   resources.multidb.db2.username = "dba"

 *   resources.multidb.db2.password = "notthatpublic"

 *   resources.multidb.db2.dbname = "db2"

 * </pre>

 *

 * @category   Zend

 * @package    Zend_Application

 * @subpackage Resource

 * @copyright  Copyright (c) 2005-2010 Zend Technologies USA Inc. (http://www.zend.com)

 * @license    http://framework.zend.com/license/new-bsd     New BSD License

 */

class Zend_Application_Resource_Multidb extends Zend_Application_Resource_ResourceAbstract

{

    /**

     * Associative array containing all configured db's

     *

     * @var array

     */

    protected $_dbs = array();

    /**

     * An instance of the default db, if set

     *

     * @var null|Zend_Db_Adapter_Abstract

     */

    protected $_defaultDb;

    /**

     * Initialize the Database Connections (instances of Zend_Db_Table_Abstract)

     *

     * @return Zend_Application_Resource_Multidb

     */

    public function init()

    {

        $options = $this->getOptions();

        if (isset($options['defaultMetadataCache'])) {

            $this->_setDefaultMetadataCache($options['defaultMetadataCache']);

            unset($options['defaultMetadataCache']);

        }

        foreach ($options as $id => $params) {

        	$adapter = $params['adapter'];

            $default = (int) (

                isset($params['isDefaultTableAdapter']) && $params['isDefaultTableAdapter']

                || isset($params['default']) && $params['default']

            );

            unset(

                $params['adapter'],

                $params['default'],

                $params['isDefaultTableAdapter']

            );

            $this->_dbs[$id] = Zend_Db::factory($adapter, $params);

            if ($default) {

                $this->_setDefault($this->_dbs[$id]);

            }

        }

        return $this;

    }

    /**

     * Determine if the given db(identifier) is the default db.

     *

     * @param  string|Zend_Db_Adapter_Abstract $db The db to determine whether it's set as default

     * @return boolean True if the given parameter is configured as default. False otherwise

     */

    public function isDefault($db)

    {

        if(!$db instanceof Zend_Db_Adapter_Abstract) {

            $db = $this->getDb($db);

        }

        return $db === $this->_defaultDb;

    }

    /**

     * Retrieve the specified database connection

     *

     * @param  null|string|Zend_Db_Adapter_Abstract $db The adapter to retrieve.

     *                                               Null to retrieve the default connection

     * @return Zend_Db_Adapter_Abstract

     * @throws Zend_Application_Resource_Exception if the given parameter could not be found

     */

    public function getDb($db = null)

    {

        if ($db === null) {

            return $this->getDefaultDb();

        }

        if (isset($this->_dbs[$db])) {

            return $this->_dbs[$db];

        }

        throw new Zend_Application_Resource_Exception(

            'A DB adapter was tried to retrieve, but was not configured'

        );

    }

    /**

     * Get the default db connection

     *

     * @param  boolean $justPickOne If true, a random (the first one in the stack)

     *                           connection is returned if no default was set.

     *                           If false, null is returned if no default was set.

     * @return null|Zend_Db_Adapter_Abstract

     */

    public function getDefaultDb($justPickOne = true)

    {

        if ($this->_defaultDb !== null) {

            return $this->_defaultDb;

        }

        if ($justPickOne) {

            return reset($this->_dbs); // Return first db in db pool

        }

        return null;

    }

    /**

     * Set the default db adapter

     *

     * @var Zend_Db_Adapter_Abstract $adapter Adapter to set as default

     */

    protected function _setDefault(Zend_Db_Adapter_Abstract $adapter)

    {

        Zend_Db_Table::setDefaultAdapter($adapter);

        $this->_defaultDb = $adapter;

    }

   /**

     * Set the default metadata cache

     * 

     * @param string|Zend_Cache_Core $cache

     * @return Zend_Application_Resource_Multidb

     */

    protected function _setDefaultMetadataCache($cache)

    {

        $metadataCache = null;

        if (is_string($cache)) {

            $bootstrap = $this->getBootstrap();

            if ($bootstrap instanceof Zend_Application_Bootstrap_ResourceBootstrapper &&

                $bootstrap->hasPluginResource('CacheManager')

            ) {

                $cacheManager = $bootstrap->bootstrap('CacheManager')

                    ->getResource('CacheManager');

                if (null !== $cacheManager && $cacheManager->hasCache($cache)) {

                    $metadataCache = $cacheManager->getCache($cache);

                }

            }

        } else if ($cache instanceof Zend_Cache_Core) {

            $metadataCache = $cache;

        }

        if ($metadataCache instanceof Zend_Cache_Core) {

            Zend_Db_Table::setDefaultMetadataCache($metadataCache);

        }

        return $this;

    }

}