/**
 * dvbcfg_source configuration file support.
 *
 * Copyright (c) 2005 by Andrew de Quincey <adq_dvb@lidskialf.net>
 *
 * Credits go to Klaus Schmidinger's VDR for coming up with this really
 * great idea.
 *
 * This library is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 */

#ifndef DVBCFG_SOURCE_BACKEND_H
#define DVBCFG_SOURCE_BACKEND_H

#include <dvbcfg_common.h>
#include <dvbcfg_source.h>

/**
 * Backend parser API.
 */
struct dvbcfg_source_backend {
        /**
         * Loads a single source from the backend and add to the supplied list.
         *
         * @param backend Pointer to the backend structure concerned.
         * @param sources Pointer to the list of sources.
         * @return 0 on success, <0 on error, or 1 on end of file.
         */
        int get_source(struct dvbcfg_source_backend* backend, struct dvbcfg_source** sources);

        /**
         * Stores a single source to the backend.
         *
         * @param backend Pointer to the backend structure concerned.
         * @param source Source to store.
         * @return 0 on success, <0 on error.
         */
        int put_source(struct dvbcfg_source_backend* backend, struct dvbcfg_source* source);
};

/**
 * Convenience method to load all sources from a backend.
 *
 * @param config_file Config filename to load.
 * @param sources Where to put the pointer to the start of the loaded sources.
 * If NULL, a new list will be created, if it points to an already initialised
 * list, the loaded sources will be appended to it.
 * @return 0 on success, or nonzero error code on failure.
 */
extern int dvbcfg_source_load(struct dvbcfg_source_backend *backend,
                              struct dvbcfg_source **sources);

/**
 * Convenience method to store all sources to a backend.
 *
 * @param config_file Config filename to save.
 * @param sources Pointer to the list of sources to save.
 * @return 0 on success, or nonzero error code on failure.
 */
extern int dvbcfg_source_save(struct dvbcfg_source_backend *backend,
                              struct dvbcfg_source *sources);


/******************************* DEFAULT BACKEND ******************************/

/**
 * The default backend stores sources in a file on disk as follows:
 *
 * <source_id> <human readable description>
 *
 * Comments begin with '#' - any characters after this will be ignored to the
 * end of the line.
 *
 * Examples:
 * S5E     Sirius 2/3
 * S13E    Hotbird 1-(5)-6
 * Tau-au-Adelaide A DVB-T transmitter in Australia serving the Adelaide area.
 * Tuk-scottish-BlackHill A DVB-T transmitter in the UK serving the central belt of scotland.
 */

/**
 * Create an instance of the default backend. This stores the source in a file
 * on disk.
 *
 * @param filename Pathname to store as. Pass NULL to use the default pathname
 * @param backend Pointer to the backend structure to initialise.
 * @return 0 on success, nonzero on error.
 */
extern int dvbcfg_source_backend_default_create(char* filename, struct dvbcfg_source_backend* backend);

/**
 * Tidy up a default backend.
 *
 * @param backend Pointer to the backend structure to destroy.
 */
extern void dvbcfg_source_backend_default_destroy(struct dvbcfg_source_backend* backend);

#endif