<?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_Service_WindowsAzure

 * @subpackage Storage

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

 * @version    $Id$

 */

/**

 * @see Zend_Log_Writer_Abstract

 */

require_once 'Zend/Log/Writer/Abstract.php';

/**

 * @category   Zend

 * @package    Zend_Service_WindowsAzure

 * @subpackage Log

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

 */

class Zend_Service_WindowsAzure_Log_Writer_WindowsAzure

    extends Zend_Log_Writer_Abstract

{

    /**

     * @var Zend_Service_Log_Formatter_Interface

     */

    protected $_formatter;

    /**

     * Connection to a windows Azure

     *

     * @var Zend_Service_Service_WindowsAzure_Storage_Table

     */

    protected $_tableStorageConnection = null;

    /**

     * Name of the table to use for logging purposes

     *

     * @var string

     */

    protected $_tableName = null;

    /**

     * Whether to keep all messages to be logged in an external buffer until the script ends and

     * only then to send the messages in batch to the logging component.

     *

     * @var bool

     */

    protected $_bufferMessages = false;

    /**

     * If message buffering is activated, it will store all the messages in this buffer and only

     * write them to table storage (in a batch transaction) when the script ends.

     *

     * @var array

     */

    protected $_messageBuffer = array();

    /**

     * @param Zend_Service_Service_WindowsAzure_Storage_Table|Zend_Service_WindowsAzure_Storage_Table $tableStorageConnection

     * @param string                                                                                  $tableName

     * @param bool                                                                                    $createTable create the Windows Azure table for logging if it does not exist

     * @param bool                                                                                    $bufferMessages

     * @throws Zend_Service_Log_Exception

     */

    public function __construct(

        Zend_Service_WindowsAzure_Storage_Table $tableStorageConnection,

        $tableName, $createTable = true, $bufferMessages = true

    )

    {

        if ($tableStorageConnection == null) {

            require_once 'Zend/Service/Log/Exception.php';

            throw new Zend_Service_Log_Exception(

                'No connection to the Windows Azure tables provided.'

            );

        }

        if (!is_string($tableName)) {

            require_once 'Zend/Service/Log/Exception.php';

            throw new Zend_Service_Log_Exception(

                'Provided Windows Azure table name must be a string.'

            );

        }

        $this->_tableStorageConnection = $tableStorageConnection;

        $this->_tableName              = $tableName;

        // create the logging table if it does not exist. It will add some overhead, so it's optional

        if ($createTable) {

            $this->_tableStorageConnection->createTableIfNotExists(

                $this->_tableName

            );

        }

        // keep messages to be logged in an internal buffer and only send them over the wire when

        // the script execution ends

        if ($bufferMessages) {

            $this->_bufferMessages = $bufferMessages;

        }

        $this->_formatter =

            new Zend_Service_WindowsAzure_Log_Formatter_WindowsAzure();

    }

    /**

     * If the log messages have been stored in the internal buffer, just send them

     * to table storage.

     */

    public function shutdown()

    {

        parent::shutdown();

        if ($this->_bufferMessages) {

            $this->_tableStorageConnection->startBatch();

            foreach ($this->_messageBuffer as $logEntity) {

                $this->_tableStorageConnection->insertEntity(

                    $this->_tableName, $logEntity

                );

            }

            $this->_tableStorageConnection->commit();

        }

    }

    /**

     * Create a new instance of Zend_Service_Log_Writer_WindowsAzure

     *

     * @param  array $config

     * @return Zend_Service_Log_Writer_WindowsAzure

     * @throws Zend_Service_Log_Exception

     */

    static public function factory($config)

    {

        $config = self::_parseConfig($config);

        $config = array_merge(

            array(

                 'connection' => null,

                 'tableName' => null,

                 'createTable' => true,

            ), $config

        );

        return new self(

            $config['connection'],

            $config['tableName'],

            $config['createTable']

        );

    }

    /**

     * The only formatter accepted is already  loaded in the constructor

     *

     * @todo enable custom formatters using the WindowsAzure_Storage_DynamicTableEntity class

     */

    public function setFormatter(

        Zend_Service_Log_Formatter_Interface $formatter

    )

    {

        require_once 'Zend/Service/Log/Exception.php';

        throw new Zend_Service_Log_Exception(

            get_class($this) . ' does not support formatting');

    }

    /**

     * Write a message to the table storage. If buffering is activated, then messages will just be

     * added to an internal buffer.

     *

     * @param  array $event

     * @return void

     * @todo   format the event using a formatted, not in this method

     */

    protected function _write($event)

    {

        $logEntity = $this->_formatter->format($event);

        if ($this->_bufferMessages) {

            $this->_messageBuffer[] = $logEntity;

        } else {

            $this->_tableStorageConnection->insertEntity(

                $this->_tableName, $logEntity

            );

        }

    }