/*
    Copyright (C) 2008 Andreas Baumann <abaumann@yahoo.com>

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#ifndef WOLF_SERVICE_H
#define WOLF_SERVICE_H

/**
 * @addtogroup wolf_win32 Windows-specific
 * @{
 */

/**
 * @addtogroup wolf_service Windows Service
 * @{
 */

/**
 * @file service.h
 * @brief helper to write a Windows service
 * @author Andreas Baumann <abaumann@yahoo.com>
 */

#define WIN32_MEAN_AND_LEAN
#include <windows.h>

#include "errors.h"

#ifdef __cplusplus
extern "C" {
#endif

/**
 * @brief structure to fill out when creating a Windows service.
 */
typedef struct wolf_service_params_t {
	LPCTSTR service_name;			/**< internal name of the service (for instance for
						     'net start "service_name"') */
	LPCTSTR service_display_name;		/**< the displayed name of the service (for instance
						     shown in the service control application) */
	LPCTSTR service_description;		/**< the description (as shown in the service control
						     application) */
} wolf_service_params_t;

/**
 * Installs the current binary as a Windows service.
 *
 * @param params   steers how the service should be created
 *
 * @return         WOLF_OK if the service was created, or an WOLF_ERR_INTERNAL
 *                 (which also gets logged with wolf_log)
 */
wolf_error_t wolf_service_install(	wolf_service_params_t params );

/**
 * Uninstalls the current binary as a Windows service.
 *
 * @param service_name the name of the service to remove from the service infrastructure
 *
 * @return         WOLF_OK if the service was removed, or an WOLF_ERR_INTERNAL
 *                 (which also gets logged with wolf_log)
 */
wolf_error_t wolf_service_remove(	LPCTSTR service_name );

/**
 * Start the service
 *
 * @param service_name the name of the service previously registered with
 *                     wolf_service_install
 * @param service_main the main function (which should implement startup/shutdown
 *                     and the main processing loop)
 *
 * @return             Doesn't return till the service terminates, then it
 *                     returns WOLF_OK.
 *                     On the other hand if we don't get called as service
 *                     we get a WOLF_ERR_INVALID_STATE indicating that the
 *                     service is run in the console, in this case you can
 *                     call wolf_service_start_console instead of this function.
 */
wolf_error_t wolf_service_start( 	LPTSTR service_name,
					LPSERVICE_MAIN_FUNCTION service_main );

wolf_error_t wolf_service_start_console( 	LPTSTR service_name,
						LPSERVICE_MAIN_FUNCTION service_main,
						DWORD argc,
						LPTSTR *argv );

/**
 * @brief events which can happen in a service
 */					
typedef enum wolf_service_event_t {
	WOLF_SERVICE_NO_EVENT,		/**< no event happened */
	WOLF_SERVICE_EVENT_TERMINATE	/**< terminate the service now */
} wolf_service_event_t;

/**
 * Suspend the current thread till an event happens. At the moment
 * we only get the SERVICE_EVENT_TERMINATE event.
 *
 * @param timeout   wait at most timeout seconds, then return also
 *                  without an event happening, error is set to
 *                  WOLF_ERR_TIMEOUT in this case
 * @param error     WOLF_OK if an event occured, WOLF_ERR_TIMEOUT if
 *                  no signal happened after timeout seconds
 *
 * @return          the event which happened
 */
typedef wolf_service_event_t (*LPWOLF_SERVICE_SUSPEND_FUNCTION)( int timeout, wolf_error_t *error );

/**
 * The current version of the suspend function, depends whether we started the service
 * in the console or really as service
 */
extern LPWOLF_SERVICE_SUSPEND_FUNCTION wolf_service_events_suspend;

#ifdef __cplusplus
}
#endif

/** @} */ /* @addtogroup wolf_service */

/** @} */ /* @addtogroup wolf_win32 */

#endif /* ifndef WOLF_SERVICE_H */