class CRedirector {

	public static $url_id;

	public static function jump( $surl ) {
		FREE_TRIAL_VERSION($surl);
	}

	public static function getJumpUrl( $surl ) {
		$vurl = self::getVirtualUrl( $surl );
		if ( !$vurl ) {
			$vurl = self::get404Url();
		}
		self::log($surl,$vurl);

		return $vurl;
	}

	public static function getVirtualUrl( $surl, $id=-1 ) {
		if ( is_array($surl) ) {
			$rs = $surl;
		} else if (!( $rs = self::getRec( $surl, $id ) )) {
			return null;
		}
		self::$url_id = $rs["url_id"];

		$vurl = self::applyModi( $rs );
		return $vurl;
	}

	public static function getVirtualUrlById( $id ) {
		return self::getVirtualUrl( "", $id );
	}

	public static function get404Url() {
		$rs = CCfgDb::get("cfgapp");
		return $rs["url-404page"];
	}

	public static function log( $surl, $vurl ) {
	}

	private static function setupRec( &$rs ) {
		if ( $rs["idata"] ) {
			$idata = CJson::decode($rs["idata"]);
			unset($idata["notes"]);
			$rs = array_merge($rs,$idata);
		} else {
			$rs["modi_id"] = 0;
		}
	}

	private static function getRec( $surl, $id=-1 ) {
		
		//-- open database
		CDb::open();

		//-- build clauses
		$clx = array();

		//-- select clause
		$sx = array(
			"url.url_id",
			"url.group_id",
			"url.durl",
			"url.modi_id",
			"modi.idata",
			"user.time_zone",
		);
		$clx[] = CSql::clSelect($sx);

		//-- from clause
		$fromx = array();
		$fromx[] = CSql::clFrom("url");
		$fromx[] = CSql::clLeftJoin("modi","modi_id",
			"url","modi_id");
		$fromx[] = CSql::clLeftJoin("user","group_id",
			"url","group_id");
		$clx[] = implode("\n",$fromx);

		//-- where clause
		$cond = array();
		if ( $id != -1 ) {
			$cond[] = CSql::clCond("url_id","=",$id);
		} else {
			$cond[] = CSql::clCond("surl","=",$surl);
		}
		if ( count($cond) > 0  ) {
			$clx[] = CSql::clWhere("AND",$cond);
		}

		//-- limit clause
		$clx[] = "LIMIT 1";

		//-- run query
		$result = CSql::query($clx);
		if ( CDb::getRowCount( $result ) == 0 ) {
			CDb::freeResult($result);
			return null;
		}

		$rs = CDb::getRowA( $result );
		self::setupRec( $rs );

		return $rs;
	}

	public static function incCounter( $url_id ) {

		CDb::open();
		CTable::updateByID( "url", "url_id", $url_id, array(
			"`cnt`=`cnt`+1"
		));
	}

	private static function applyModi( $rs ) {
		$durl = $rs["durl"];

		if ( !$rs["modi_id"] ) {
			return $durl;
		}

		if ( !self::inValidTimeRange( $rs ) ) {
			return $durl;
		}

		if ( $rs["b_get_params"] ) {
			$durl = self::appendParam($durl,$rs["get_params"]);
		}

		$vurl = ( $rs["b_rurl"] ) ? $rs["rurl"] : $durl;

		if ( $rs["b_rurl"] ) {
			if ( $rs["b_send_durl"] ) {
				if ( $rs["b_base64"] ) {
					$val = base64_encode($durl);
				} else {
					$val = $durl;
				}
				$param = $rs["durlkey"] . "=" . urlencode($val);
				$vurl = self::appendParam($vurl,$param);
			}
		}

		return $vurl;
	}

	private static function inValidTimeRange( $rs ) {

		if ( !$rs["b_period"] ) {
			return true;
		}

		CAppUTC::setup( $rs["time_zone"] );
		$utc_now = CAppUTC::utcTStrNow();

		if ( !empty($rs["dt_start"]) && 
			( $utc_now < CAppUTC::toUTC($rs["dt_start"]) ) ) {
			return false;
		}

		if ( !empty($rs["dt_end"]) && 
			( $utc_now > CAppUTC::toUTC($rs["dt_end"]) ) ) {
			return false;
		}

		return true;
	}

	private static function appendParam( $url, $param ) {
		if ( empty($param) ) {
			return $url;
		}

		//-- fragment
		$fragment = null;
		$ux = explode("#",$url);
		if ( count($ux) > 1 ) {
			$url = array_shift($ux);
			$fragment = implode("#",$ux);
		}

		//-- query string
		if ( strpos($url,"?") !== false ) {
			$ch = substr($url, -1);
			if (( $ch != "?" ) && ( $ch != "&" )) {
				$url .= "&";
			}
		} else {
			$url .= "?";
		}

		//-- normalize GET parameters
		$ch = substr($param,0,1);
		if (( $ch == "?" ) || ( $ch == "&" )) {
			$param = substr($param,1);
		}

		//-- add GET parameters
		$url .= $param;

		//-- restore fragment
		if ( !is_null($fragment) ) {
			$url .= ( "#" . $fragment );
		}

		return $url;
	}
}