<?php
/**
 * TLogRouter, TLogRoute, TFileLogRoute, TEmailLogRoute class file
 *
 * @author Qiang Xue <qiang.xue@gmail.com>
 * @link http://www.pradosoft.com/
 * @copyright Copyright &copy; 2005-2014 PradoSoft
 * @license http://www.pradosoft.com/license/
 * @package System.Util
 */

/**
 * TDbLogRoute class
 *
 * TDbLogRoute stores log messages in a database table.
 * To specify the database table, set {@link setConnectionID ConnectionID} to be
 * the ID of a {@link TDataSourceConfig} module and {@link setLogTableName LogTableName}.
 * If they are not setting, an SQLite3 database named 'sqlite3.log' will be created and used
 * under the runtime directory.
 *
 * By default, the database table name is 'pradolog'. It has the following structure:
 * <code>
 *	CREATE TABLE pradolog
 *  (
 *		log_id INTEGER NOT NULL PRIMARY KEY,
 *		level INTEGER,
 *		category VARCHAR(128),
 *		logtime VARCHAR(20),
 *		message VARCHAR(255)
 *   );
 * </code>
 *
 * @author Qiang Xue <qiang.xue@gmail.com>
 * @package System.Util
 * @since 3.1.2
 */
class TDbLogRoute extends TLogRoute
{
	/**
	 * @var string the ID of TDataSourceConfig module
	 */
	private $_connID='';
	/**
	 * @var TDbConnection the DB connection instance
	 */
	private $_db;
	/**
	 * @var string name of the DB log table
	 */
	private $_logTable='pradolog';
	/**
	 * @var boolean whether the log DB table should be created automatically
	 */
	private $_autoCreate=true;

	/**
	 * Destructor.
	 * Disconnect the db connection.
	 */
	public function __destruct()
	{
		if($this->_db!==null)
			$this->_db->setActive(false);
	}

	/**
	 * Initializes this module.
	 * This method is required by the IModule interface.
	 * It initializes the database for logging purpose.
	 * @param TXmlElement configuration for this module, can be null
	 * @throws TConfigurationException if the DB table does not exist.
	 */
	public function init($config)
	{
		$db=$this->getDbConnection();
		$db->setActive(true);

		$sql='SELECT * FROM '.$this->_logTable.' WHERE 0=1';
		try
		{
			$db->createCommand($sql)->query()->close();
		}
		catch(Exception $e)
		{
			// DB table not exists
			if($this->_autoCreate)
				$this->createDbTable();
			else
				throw new TConfigurationException('db_logtable_inexistent',$this->_logTable);
		}

		parent::init($config);
	}

	/**
	 * Stores log messages into database.
	 * @param array list of log messages
	 */
	protected function processLogs($logs)
	{
		$sql='INSERT INTO '.$this->_logTable.'(level, category, logtime, message) VALUES (:level, :category, :logtime, :message)';
		$command=$this->getDbConnection()->createCommand($sql);
		foreach($logs as $log)
		{
			$command->bindValue(':message',$log[0]);
			$command->bindValue(':level',$log[1]);
			$command->bindValue(':category',$log[2]);
			$command->bindValue(':logtime',$log[3]);
			$command->execute();
		}
	}

	/**
	 * Creates the DB table for storing log messages.
	 * @todo create sequence for PostgreSQL
	 */
	protected function createDbTable()
	{
		$db = $this->getDbConnection();
		$driver=$db->getDriverName();
		$autoidAttributes = '';
		if($driver==='mysql')
			$autoidAttributes = 'AUTO_INCREMENT';

		$sql='CREATE TABLE '.$this->_logTable.' (
			log_id INTEGER NOT NULL PRIMARY KEY ' . $autoidAttributes . ',
			level INTEGER,
			category VARCHAR(128),
			logtime VARCHAR(20),
			message VARCHAR(255))';
		$db->createCommand($sql)->execute();
	}

	/**
	 * Creates the DB connection.
	 * @param string the module ID for TDataSourceConfig
	 * @return TDbConnection the created DB connection
	 * @throws TConfigurationException if module ID is invalid or empty
	 */
	protected function createDbConnection()
	{
		if($this->_connID!=='')
		{
			$config=$this->getApplication()->getModule($this->_connID);
			if($config instanceof TDataSourceConfig)
				return $config->getDbConnection();
			else
				throw new TConfigurationException('dblogroute_connectionid_invalid',$this->_connID);
		}
		else
		{
			$db=new TDbConnection;
			// default to SQLite3 database
			$dbFile=$this->getApplication()->getRuntimePath().'/sqlite3.log';
			$db->setConnectionString('sqlite:'.$dbFile);
			return $db;
		}
	}

	/**
	 * @return TDbConnection the DB connection instance
	 */
	public function getDbConnection()
	{
		if($this->_db===null)
			$this->_db=$this->createDbConnection();
		return $this->_db;
	}

	/**
	 * @return string the ID of a {@link TDataSourceConfig} module. Defaults to empty string, meaning not set.
	 */
	public function getConnectionID()
	{
		return $this->_connID;
	}

	/**
	 * Sets the ID of a TDataSourceConfig module.
	 * The datasource module will be used to establish the DB connection for this log route.
	 * @param string ID of the {@link TDataSourceConfig} module
	 */
	public function setConnectionID($value)
	{
		$this->_connID=$value;
	}

	/**
	 * @return string the name of the DB table to store log content. Defaults to 'pradolog'.
	 * @see setAutoCreateLogTable
	 */
	public function getLogTableName()
	{
		return $this->_logTable;
	}

	/**
	 * Sets the name of the DB table to store log content.
	 * Note, if {@link setAutoCreateLogTable AutoCreateLogTable} is false
	 * and you want to create the DB table manually by yourself,
	 * you need to make sure the DB table is of the following structure:
	 * (key CHAR(128) PRIMARY KEY, value BLOB, expire INT)
	 * @param string the name of the DB table to store log content
	 * @see setAutoCreateLogTable
	 */
	public function setLogTableName($value)
	{
		$this->_logTable=$value;
	}

	/**
	 * @return boolean whether the log DB table should be automatically created if not exists. Defaults to true.
	 * @see setAutoCreateLogTable
	 */
	public function getAutoCreateLogTable()
	{
		return $this->_autoCreate;
	}

	/**
	 * @param boolean whether the log DB table should be automatically created if not exists.
	 * @see setLogTableName
	 */
	public function setAutoCreateLogTable($value)
	{
		$this->_autoCreate=TPropertyValue::ensureBoolean($value);
	}

}