/*

 * Hedgewars, a free turn based strategy game

 * Copyright (C) 2012 Simeon Maxein <smaxein@googlemail.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 2

 * 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, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.

 */

/**

 * Functions for querying a map preview from the engine, which includes both a two-color image

 * and the number of hogs this map is suitable for.

 *

 * The general usage is to first create a mapconn object by calling flib_mapconn_create.

 * That will cause the frontlib to listen on a random port which can be queried using

 * flib_mapconn_getport(). You should also register your callback functions right at the start

 * to ensure you don't miss any callbacks.

 *

 * Next, start the engine (that part is up to you) with the appropriate command line arguments

 * for a map preview request.

 *

 * In order to allow the mapconn to run, you should regularly call flib_mapconn_tick(), which

 * performs network I/O and calls your callbacks if the map has been generated or an error

 * has occurred. Once either the onSuccess or onFailure callback is called, you should destroy

 * the mapconn and stop calling tick().

 */

#ifndef IPC_MAPCONN_H_

#define IPC_MAPCONN_H_

#include "../model/map.h"

#include <stdint.h>

#define MAPIMAGE_WIDTH 256

#define MAPIMAGE_HEIGHT 128

#define MAPIMAGE_BYTES (MAPIMAGE_WIDTH/8*MAPIMAGE_HEIGHT)

typedef struct _flib_mapconn flib_mapconn;

/**

 * Start a new map rendering connection (mapconn). This means a listening socket

 * will be started on a random unused port, waiting for a connection from the

 * engine process. Once this connection is established, the required information

 * will be sent to the engine, and the reply is read.

 *

 * The map must be a regular, maze or drawn map - for a preview of a named map,

 * use the preview images in the map's directory, and for the hog count read the

 * map information (e.g. using flib_mapcfg_read).

 *

 * No NULL parameters allowed, returns NULL on failure.

 * Use flib_mapconn_destroy to free the returned object.

 */

flib_mapconn *flib_mapconn_create(const flib_map *mapdesc);

/**

 * Destroy the mapconn object. Passing NULL is allowed and does nothing.

 * flib_mapconn_destroy may be called from inside a callback function.

 */

void flib_mapconn_destroy(flib_mapconn *conn);

/**

 * Returns the port on which the mapconn is listening. Only fails if you

 * pass NULL (not allowed), in that case 0 is returned.

 */

int flib_mapconn_getport(flib_mapconn *conn);

/**

 * Set a callback which will receive the rendered map if the rendering succeeds.

 *

 * Expected callback signature:

 * void handleSuccess(void *context, const uint8_t *bitmap, int numHedgehogs)

 *

 * The context passed to the callback is the same pointer you provided when

 * registering the callback. bitmap is a pointer to a buffer of size MAPIMAGE_BYTES

 * containing a bit-packed image of size MAPIMAGE_WIDTH * MAPIMAGE_HEIGHT.

 * numHedgehogs is the number of hogs that fit on this map.

 *

 * The bitmap pointer passed to the callback belongs to the caller,

 * so it should not be stored elsewhere. Note that it remains valid

 * inside the callback method even if flib_mapconn_destroy is called.

 */

void flib_mapconn_onSuccess(flib_mapconn *conn, void (*callback)(void* context, const uint8_t *bitmap, int numHedgehogs), void *context);

/**

 * Set a callback which will receive an error message if rendering fails.

 *

 * Expected callback signature:

 * void handleFailure(void *context, const char *errormessage)

 *

 * The context passed to the callback is the same pointer you provided when

 * registering the callback.

 *

 * The error message passed to the callback belongs to the caller,

 * so it should not be stored elsewhere. Note that it remains valid

 * inside the callback method even if flib_mapconn_destroy is called.

 */

void flib_mapconn_onFailure(flib_mapconn *conn, void (*callback)(void* context, const char *errormessage), void *context);

/**

 * Perform I/O operations and call callbacks if something interesting happens.

 * Should be called regularly.

 */

void flib_mapconn_tick(flib_mapconn *conn);

#endif