/* DE1: $Id: dd_api.h 3171 2006-05-17 18:13:44Z danij $
 * Copyright (C) 2003, 2004 Jaakko Keränen <jaakko.keranen@iki.fi>
 *
 * 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: http://www.opensource.org/
 */

/*
 * dd_api.h: Data Structures for the Engine/Game Interface
 */

#ifndef __DOOMSDAY_GAME_API_H__
#define __DOOMSDAY_GAME_API_H__

#include "dd_share.h"

/*
 * The routines/data exported out of the Doomsday engine:
 *
 * This structure contains pointers to routines that can have alternative
 * handlers in the engine. Also, some select global variables are exported
 * using this structure (most importantly the map data).
 */
typedef struct game_import_s {
    int             apiSize;       // sizeof(game_import_t)
    int             version;       // Doomsday Engine version.

    //
    // DATA
    //
    // Data arrays.
    mobjinfo_t    **mobjinfo;
    state_t       **states;
    sprname_t     **sprnames;
    ddtext_t      **text;

    // General information.
    int            *validcount;
    fixed_t        *topslope;
    fixed_t        *bottomslope;

    // Thinker data (DO NOT CHANGE).
    thinker_t      *thinkercap;    // The head and tail of the thinker list

    /*
    // Map data, pointers to the arrays.
    int            *numvertexes;
    int            *numsegs;
    int            *numsectors;
    int            *numsubsectors;
    int            *numnodes;
    int            *numlines;
    int            *numsides;
    int            *numthings;
    void          **vertexes;
    void          **segs;
    void          **sectors;
    void          **subsectors;
    void          **nodes;
    void          **lines;
    void          **sides;
    void          **things;
    short         **blockmaplump;
    short         **blockmap;
    int            *bmapwidth;
    int            *bmapheight;
    int            *bmaporgx;
    int            *bmaporgy;
    byte          **rejectmatrix;
    void         ***polyblockmap;
    void          **polyobjs;
    int            *numpolyobjs;
    */
} game_import_t;                   // game import == engine export

/*
 * The routines/data exported from the game DLL.
 */
typedef struct {
    int             apiSize;       // sizeof(game_export_t)

    // Base-level.
    void            (*PreInit) (void);
    void            (*PostInit) (void);
    void            (*Shutdown) (void);
    void            (*UpdateState) (int step);
    char           *(*Get) (int id);

    // Ticcmds.
    void            (*BuildTicCmd) (void *cmd, float elapsedTime);
    void            (*MergeTicCmd) (void *dest, void *src);

    // Networking.
    int             (*NetServerStart) (int before);
    int             (*NetServerStop) (int before);
    int             (*NetConnect) (int before);
    int             (*NetDisconnect) (int before);
    int             (*NetPlayerEvent) (int playernum, int type, void *data);
    int             (*NetWorldEvent) (int type, int parm, void *data);
    void            (*HandlePacket) (int fromplayer, int type, void *data,
                                     int length);

    // Tickers.
    void            (*Ticker) (void);

    // Responders.
    boolean         (*PrivilegedResponder) (event_t *event);
    boolean         (*G_Responder) (event_t *event);
    boolean         (*FallbackResponder) (event_t *event);

    // Refresh.
    void            (*BeginFrame) (void);
    void            (*EndFrame) (void);
    void            (*G_Drawer) (void);
    void            (*MN_Drawer) (void);
    void            (*ConsoleBackground) (int *width, int *height);
    void            (*R_Init) (void);

    // Miscellaneous.
    void            (*MobjThinker) ();
    fixed_t         (*MobjFriction) (void *mobj);   // Returns a friction factor.

    // Main structure sizes.
    int             ticcmd_size;   // sizeof(ticcmd_t)
/*
    int             vertex_size;   // etc.
    int             seg_size;
    int             sector_size;
    int             subsector_size;
    int             node_size;
    int             line_size;
    int             side_size;
    int             thing_size;
    int             polyobj_size;
*/

    // Map data setup
    // This routine is called before any data is read
    // (with the number of items to be read) to allow the
    // game do any initialization it needs (eg create an
    // array of its own private data structures).
    void            (*SetupForMapData)      (int type, int num);

    // The engine calls this when the map data element id does
    // not match any internal (engine side) map data property.
    // It is assumed that it is game specifc data and that
    // the game will handle what is done with it.
    int             (*HandleMapDataProperty) (int id, int dtype, int prop,
                                             int type, void *data);

    // This routine is called when trying to assign a value read
    // from the map data (to a property known to us) that we don't
    // know what to do with.

    // (eg the side->toptexture field contains a text string that
    // we don't understand but the game might).

    // The action code returned by the game depends on the context.
    int             (*HandleMapDataPropertyValue) (int id, int dtype, int prop,
                                                   int type, void *data);
    // Post map setup
    // The engine calls this to inform the game of any changes it is
    // making to map data object to which the game might want to
    // take further action.
    int             (*HandleMapObjectStatusReport) (int code, int id, int dtype,
                                                    void *data);
} game_export_t;

typedef game_export_t *(*GETGAMEAPI) (game_import_t *);

#endif