<?php
/**
 * EGroupware API - Storage history logging
 *
 * @link http://www.egroupware.org
 * @author Joseph Engo <jengo@phpgroupware.org>
 * @copyright 2001 by Joseph Engo <jengo@phpgroupware.org>
 * @author Ralf Becker <RalfBecker-AT-outdoor-training.de> new DB-methods and search
 *
 * @license http://opensource.org/licenses/gpl-license.php GPL - GNU General Public License
 * @package api
 * @subpackage storage
 * @access public
 * @version $Id$
 */

namespace EGroupware\Api\Storage;

use EGroupware\Api;

/**
 * Record history logging service
 *
 * This class need to be instanciated for EACH app, which wishes to use it!
 */
class History
{
	/**
	 * Reference to the global db object
	 *
	 * @var Api\Db
	 */
	var $db;
	const TABLE = 'egw_history_log';
	/**
	 * App.name this class is instanciated for / working on
	 *
	 * @var string
	 */
	var $appname;
	var $user;
	var $types = array(
		'C' => 'Created',
		'D' => 'Deleted',
		'E' => 'Edited'
	);

	/**
	 * Constructor
	 *
	 * @param string $appname app name this instance operates on
	 * @return historylog
	 */
	function __construct($appname='',$user=null)
	{
		$this->appname = $appname ? $appname : $GLOBALS['egw_info']['flags']['currentapp'];
		$this->user = !is_null($user) ? $user : $GLOBALS['egw_info']['user']['account_id'];

		if (is_object($GLOBALS['egw_setup']->db))
		{
			$this->db = $GLOBALS['egw_setup']->db;
		}
		else
		{
			$this->db = $GLOBALS['egw']->db;
		}
	}

	/**
	 * Delete the history-log of one or multiple records of $this->appname
	 *
	 * @param int|array $record_id one or more id's of $this->appname, or null to delete ALL records of $this->appname
	 * @return int number of deleted records/rows (0 is not necessaryly an error, it can just mean there's no record!)
	 */
	function delete($record_id)
	{
		$where = array('history_appname' => $this->appname);

		if (is_array($record_id) || is_numeric($record_id))
		{
			$where['history_record_id'] = $record_id;
		}
		$this->db->delete(self::TABLE,$where,__LINE__,__FILE__);

		return $this->db->affected_rows();
	}

	/**
	 * Add a history record, if $new_value != $old_value
	 *
	 * @param string $status 2 letter code: eg. $this->types: C=Created, D=Deleted, E=Edited
	 * @param int $record_id it of the record in $this->appname (set by the constructor)
	 * @param string $new_value new value
	 * @param string $old_value old value
	 */
	function add($status,$record_id,$new_value,$old_value)
	{
		if ($new_value != $old_value)
		{
			$this->db->insert(self::TABLE,array(
				'history_record_id' => $record_id,
				'history_appname'   => $this->appname,
				'history_owner'     => $this->user,
				'history_status'    => $status,
				'history_new_value' => $new_value,
				'history_old_value' => $old_value,
				'history_timestamp' => time(),
				'sessionid' => $GLOBALS['egw']->session->sessionid_access_log,
			),false,__LINE__,__FILE__);
		}
	}

	/**
	 * Static function to add a history record
	 */
	public static function static_add($appname, $id, $user, $field_code, $new_value, $old_value = '')
	{
		if ($new_value != $old_value)
		{
			$GLOBALS['egw']->db->insert(self::TABLE,array(
				'history_record_id' => $id,
				'history_appname'   => $appname,
				'history_owner'     => (int)$user,
				'history_status'    => $field_code,
				'history_new_value' => $new_value,
				'history_old_value' => $old_value,
				'history_timestamp' => time(),
				'sessionid' => $GLOBALS['egw']->session->sessionid_access_log,
			),false,__LINE__,__FILE__);
		}
	}

	/**
	 * Search history-log
	 *
	 * @param array|int $filter array with filters, or int record_id
	 * @param string $order ='history_id' sorting after history_id is identical to history_timestamp
	 * @param string $sort ='DESC'
	 * @param int $limit =null only return this many entries
	 * @return array of arrays with keys id, record_id, appname, owner (account_id), status, new_value, old_value,
	 * 	timestamp (Y-m-d H:i:s in servertime), user_ts (timestamp in user-time)
	 */
	function search($filter,$order='history_id',$sort='DESC',$limit=null)
	{
		if (!is_array($filter)) $filter = is_numeric($filter) ? array('history_record_id' => $filter) : array();

		if (!$order || !preg_match('/^[a-z0-9_]+$/i',$order) || !preg_match('/^(asc|desc)?$/i',$sort))
		{
			$orderby = 'ORDER BY history_id DESC';
		}
		else
		{
			$orderby = "ORDER BY $order $sort";
		}
		foreach($filter as $col => $value)
		{
			if (!is_numeric($col) && substr($col,0,8) != 'history_')
			{
				$filter['history_'.$col] = $value;
				unset($filter[$col]);
			}
		}
		if (!isset($filter['history_appname'])) $filter['history_appname'] = $this->appname;

		// do not try to read all history entries of an app
		if (!$filter['history_record_id']) return array();

		$rows = array();
		foreach($this->db->select(self::TABLE, '*', $filter, __LINE__, __FILE__,
			isset($limit) ? 0 : false, $orderby, 'phpgwapi', $limit) as $row)
		{
			$row['user_ts'] = $this->db->from_timestamp($row['history_timestamp']) + 3600 * $GLOBALS['egw_info']['user']['preferences']['common']['tz_offset'];
			$rows[] = Api\Db::strip_array_keys($row,'history_');
		}
		return $rows;
	}

	/**
	 * Get a slice of history records
	 *
	 * Similar to search(), except this one can take a start and a number of records
	 *
	 * @see Base::get_rows()
	 */
	public static function get_rows(&$query, &$rows)
	{
		$filter = array();
		$rows = array();
		$filter['history_appname'] = $query['appname'];
		$filter['history_record_id'] = $query['record_id'];
		if(is_array($query['colfilter'])) {
			foreach($query['colfilter'] as $column => $value) {
				$filter[$column] = $value;
			}
		}
		if ($GLOBALS['egw']->db->Type == 'mysql' && $GLOBALS['egw']->db->ServerInfo['version'] >= 4.0)
		{
			$mysql_calc_rows = 'SQL_CALC_FOUND_ROWS ';
		}
		else
		{
			$total = $GLOBALS['egw']->db->select(self::TABLE,'COUNT(*)',$filter,__LINE__,__FILE__,false,'','phpgwapi',0)->fetchColumn();
		}
		// filter out private (or no longer defined) custom fields
		if ($filter['history_appname'])
		{
			$to_or[] = "history_status NOT LIKE '#%'";
			// explicitly allow "##" used to store iCal/vCard X-attributes
			if (in_array($filter['history_appname'], array('calendar','infolog','addressbook')))
			{
				$to_or[] = "history_status LIKE '##%'";
			}
			if (($cfs = Customfields::get($filter['history_appname'])))
			{
				$to_or[] =  'history_status IN ('.implode(',', array_map(function($str)
				{
					return $GLOBALS['egw']->db->quote('#'.$str);
				}, array_keys($cfs))).')';
			}
			$filter[] = '('.implode(' OR ', $to_or).')';
		}
		$_query = array(array(
			'table' => self::TABLE,
			'cols' => array('history_id', 'history_record_id','history_appname','history_owner','history_status','history_new_value', 'history_timestamp','history_old_value'),
			'where' => $filter,
		));

		// Add in files, if possible
		if($GLOBALS['egw_info']['user']['apps']['filemanager'] &&
			$file = Api\Vfs\Sqlfs\StreamWrapper::url_stat("/apps/{$query['appname']}/{$query['record_id']}",STREAM_URL_STAT_LINK))
		{
			$_query[] = array(
				'table' => Api\Vfs\Sqlfs\StreamWrapper::TABLE,
				'cols' =>array('fs_id', 'fs_dir', "'filemanager'",'COALESCE(fs_modifier,fs_creator)',"'~file~'",'fs_name','fs_modified', 'fs_mime'),
				'where' => array('fs_dir' => $file['ino'])
			);
		}
		$new_file_id = array();
		foreach($GLOBALS['egw']->db->union(
			$_query,
			__LINE__, __FILE__,
			' ORDER BY ' . ($query['order'] ? $query['order'] : 'history_timestamp') . ' ' . ($query['sort'] ? $query['sort'] : 'DESC'),
			$query['start'],
			$query['num_rows']
		) as $row)
		{
			$row['user_ts'] = $GLOBALS['egw']->db->from_timestamp($row['history_timestamp']) + 3600 * $GLOBALS['egw_info']['user']['preferences']['common']['tz_offset'];

			// Explode multi-part values
			foreach(array('history_new_value','history_old_value') as $field)
			{
				if(strpos($row[$field],Tracking::ONE2N_SEPERATOR) !== false)
				{
					$row[$field] = explode(Tracking::ONE2N_SEPERATOR,$row[$field]);
				}
			}
			// Get information needed for proper display
			if($row['history_appname'] == 'filemanager')
			{
				$new_version = $new_file_id[$row['history_new_value']];
				$new_file_id[$row['history_new_value']] = count($rows);
				$path = Api\Vfs\Sqlfs\StreamWrapper::id2path($row['history_id']);

				// Apparently we don't have to do anything with it, just ask...
				// without this, previous versions are not handled properly
				Api\Vfs::getExtraInfo($path);

				$row['history_new_value'] = array(
					'path' => $path,
					'name' => Api\Vfs::basename($path),
					'mime' => $row['history_old_value']
				);
				$row['history_old_value'] = '';
				if($new_version !== null)
				{
					$rows[$new_version]['old_value'] = $row['history_new_value'];
				}
			}
			$rows[] = Api\Db::strip_array_keys($row,'history_');
		}
		if ($mysql_calc_rows)
		{
			$total = $GLOBALS['egw']->db->query('SELECT FOUND_ROWS()')->fetchColumn();
		}

		return $total;
	}
}