libakgl/src/game.c

#include <SDL3/SDL.h>
#include <SDL3_image/SDL_image.h>
#include <SDL3_mixer/SDL_mixer.h>
#include <SDL3_ttf/SDL_ttf.h>
#include <stdio.h>
#include <akerror.h>
#include <semver.h>

#include <akstdlib.h>
#include <akgl/game.h>
#include <akgl/controller.h>
#include <akgl/tilemap.h>
#include <akgl/sprite.h>
#include <akgl/heap.h>
#include <akgl/registry.h>
#include <akgl/staticstring.h>
#include <akgl/iterator.h>
#include <akgl/SDL_GameControllerDB.h>

SDL_Window *window = NULL;
SDL_Renderer *renderer = NULL;
akgl_Frame ball;
akgl_Frame paddle1;
akgl_Frame paddle2;
akgl_Frame table;
akgl_Tilemap gamemap;
MIX_Audio *bgm = NULL;
MIX_Mixer *akgl_mixer = NULL;
MIX_Track *akgl_tracks[AKGL_GAME_AUDIO_MAX_TRACKS];
SDL_FRect camera;
akgl_Game game;

akerr_ErrorContext AKERR_NOIGNORE *akgl_game_init()
{
    int i = 0;
    PREPARE_ERROR(errctx);
    ATTEMPT {
	strncpy((char *)&game.libversion, AKGL_VERSION, 32);
	game.gameStartTime = SDL_GetTicksNS();
	game.lastIterTime = game.gameStartTime;
	game.lastFPSTime = game.gameStartTime;
	FAIL_ZERO_BREAK(errctx, strlen((char *)&game.name), AKERR_NULLPOINTER, "Must provide game name");
	FAIL_ZERO_BREAK(errctx, strlen((char *)&game.version), AKERR_NULLPOINTER, "Must provide game version");
	FAIL_ZERO_BREAK(errctx, strlen((char *)&game.uri), AKERR_NULLPOINTER, "Must provide game uri");
	CATCH(errctx, akgl_heap_init());
	CATCH(errctx, akgl_registry_init_actor());
	CATCH(errctx, akgl_registry_init_sprite());
	CATCH(errctx, akgl_registry_init_spritesheet());
	CATCH(errctx, akgl_registry_init_character());
	CATCH(errctx, akgl_registry_init_font());
	CATCH(errctx, akgl_registry_init_music());
	CATCH(errctx, akgl_registry_init_properties());
	CATCH(errctx, akgl_registry_init_actor_state_strings());
    } CLEANUP {
    } PROCESS(errctx) {
    } FINISH(errctx, true)
	  
    SDL_SetAppMetadata(game.name, game.version, game.uri);

    for ( i = 0 ; i < AKGL_MAX_CONTROL_MAPS; i++ ) {
	memset(&GAME_ControlMaps[i], 0x00, sizeof(akgl_ControlMap));
    }
    
    FAIL_ZERO_RETURN(
	errctx,
	SDL_Init(SDL_INIT_VIDEO | SDL_INIT_GAMEPAD | SDL_INIT_AUDIO),
	AKGL_ERR_SDL,
	"Couldn't initialize SDL: %s",
	SDL_GetError());

    // Load the Game Controller DB

    for ( i = 0; i < AKGL_SDL_GAMECONTROLLER_DB_LEN ; i++ ) {
	if ( SDL_AddGamepadMapping(SDL_GAMECONTROLLER_DB[i]) == -1 ) {
	    FAIL_ZERO_RETURN(errctx, 0, AKGL_ERR_SDL, "%s", SDL_GetError());
	}
    }
    
    FAIL_ZERO_RETURN(
	errctx,
	SDL_CreateWindowAndRenderer(game.uri, game.screenwidth, game.screenheight, 0, &window, &renderer),
	AKGL_ERR_SDL,
	"Couldn't create window/renderer: %s",
	SDL_GetError());
    
    FAIL_ZERO_RETURN(
	errctx,
	MIX_Init(),
	AKGL_ERR_SDL,
	"Couldn't initialize audio: %s",
	SDL_GetError());
    akgl_mixer = MIX_CreateMixerDevice(SDL_AUDIO_DEVICE_DEFAULT_PLAYBACK, 0);
    FAIL_ZERO_RETURN(
	errctx,
	akgl_mixer,
	AKGL_ERR_SDL,
	"Unable to create mixer device: %s",
	SDL_GetError());

    FAIL_ZERO_RETURN(
	errctx,
	TTF_Init(),
	AKGL_ERR_SDL,
	"Couldn't initialize front engine: %s",
	SDL_GetError());

    camera.x = 0;
    camera.y = 0;
    camera.w = game.screenwidth;
    camera.h = game.screenheight;
    SUCCEED(errctx);
}

void akgl_game_updateFPS()
{
    SDL_Time curTime;
    curTime = SDL_GetTicksNS();
    if ( (curTime - game.lastFPSTime) > AKGL_TIME_ONESEC_NS ) {
	game.fps = game.framesSinceUpdate;
	game.framesSinceUpdate = 0;
	game.lastFPSTime = curTime;
    }
    game.framesSinceUpdate += 1;
    game.lastIterTime = curTime;
}

/*
 * entity name -> pointer map tables
 */

void akgl_game_save_actorname_iterator(void *userdata, SDL_PropertiesID props, const char *name)
{
    FILE *fp = (FILE *)userdata;
    akgl_Actor *actor = NULL;
    PREPARE_ERROR(errctx);
    ATTEMPT {
	FAIL_ZERO_BREAK(errctx, fp, AKERR_NULLPOINTER, "NULL file pointer");
	fwrite((char *)name, 1, AKGL_ACTOR_MAX_NAME_LENGTH, fp);
	actor = SDL_GetPointerProperty(props, name, NULL);
	fwrite(&actor, 1, sizeof(akgl_Actor *), fp);
    } CLEANUP {
    } PROCESS(errctx) {
    } FINISH_NORETURN(errctx);
}

void akgl_game_save_spritename_iterator(void *userdata, SDL_PropertiesID props, const char *name)
{
    FILE *fp = (FILE *)userdata;
    akgl_Sprite *sprite = NULL;
    PREPARE_ERROR(errctx);
    ATTEMPT {
	FAIL_ZERO_BREAK(errctx, fp, AKERR_NULLPOINTER, "NULL file pointer");
	sprite = SDL_GetPointerProperty(props, name, NULL);
	fwrite((char *)name, 1, AKGL_SPRITE_MAX_NAME_LENGTH, fp);
	fwrite(&sprite, 1, sizeof(akgl_Sprite *), fp);
    } CLEANUP {
    } PROCESS(errctx) {
    } FINISH_NORETURN(errctx);
}

void akgl_game_save_spritesheetname_iterator(void *userdata, SDL_PropertiesID props, const char *name)
{
    FILE *fp = (FILE *)userdata;
    akgl_SpriteSheet *spritesheet = NULL;
    PREPARE_ERROR(errctx);
    ATTEMPT {
	FAIL_ZERO_BREAK(errctx, fp, AKERR_NULLPOINTER, "NULL file pointer");
	spritesheet = SDL_GetPointerProperty(props, name, NULL);
	fwrite((char *)name, 1, AKGL_SPRITE_SHEET_MAX_FILENAME_LENGTH, fp);
	fwrite(&spritesheet, 1, sizeof(akgl_SpriteSheet *), fp);
    } CLEANUP {
    } PROCESS(errctx) {
    } FINISH_NORETURN(errctx);
}

void akgl_game_save_charactername_iterator(void *userdata, SDL_PropertiesID props, const char *name)
{
    FILE *fp = (FILE *)userdata;
    PREPARE_ERROR(errctx);
    akgl_Character *character = NULL;
    ATTEMPT {
	FAIL_ZERO_BREAK(errctx, fp, AKERR_NULLPOINTER, "NULL file pointer");
	character = SDL_GetPointerProperty(props, name, NULL);
	fwrite((char *)name, 1, AKGL_SPRITE_MAX_CHARACTER_NAME_LENGTH, fp);
	fwrite(&character, 1, sizeof(akgl_Character *), fp);
    } CLEANUP {
    } PROCESS(errctx) {
    } FINISH_NORETURN(errctx);
}

akerr_ErrorContext AKERR_NOIGNORE *akgl_game_save_actors(FILE *fp)
{
    PREPARE_ERROR(errctx);
    char nullval = 0x00;
    
    ATTEMPT {
	FAIL_ZERO_BREAK(errctx, fp, AKERR_NULLPOINTER, "NULL file pointer");
	// write the actor name pointer table
	SDL_EnumerateProperties(
	    AKGL_REGISTRY_ACTOR,
	    &akgl_game_save_actorname_iterator,
	    (void *)fp);
	fwrite((void *)&nullval, 1, AKGL_ACTOR_MAX_NAME_LENGTH, fp);
	fwrite((void *)&nullval, 1, sizeof(akgl_Actor *), fp);
	// write the sprite name pointer table
	SDL_EnumerateProperties(
	    AKGL_REGISTRY_SPRITE,
	    &akgl_game_save_spritename_iterator,
	    (void *)fp);
	fwrite((void *)&nullval, 1, AKGL_SPRITE_MAX_NAME_LENGTH, fp);
	fwrite((void *)&nullval, 1, sizeof(akgl_Sprite *), fp);
	// write the spritesheet name pointer table
	SDL_EnumerateProperties(
	    AKGL_REGISTRY_SPRITESHEET,
	    &akgl_game_save_spritesheetname_iterator,
	    (void *)fp);
	fwrite((void *)&nullval, 1, AKGL_SPRITE_SHEET_MAX_FILENAME_LENGTH, fp);
	fwrite((void *)&nullval, 1, sizeof(akgl_SpriteSheet *), fp);
	// write the character name pointer table
	SDL_EnumerateProperties(
	    AKGL_REGISTRY_CHARACTER,
	    &akgl_game_save_charactername_iterator,
	    (void *)fp);
	fwrite((void *)&nullval, 1, AKGL_SPRITE_MAX_CHARACTER_NAME_LENGTH, fp);
	fwrite((void *)&nullval, 1, sizeof(akgl_Character *), fp);
    } CLEANUP {
    } PROCESS(errctx) {
    } FINISH(errctx, true);
    SUCCEED_RETURN(errctx);
}

akerr_ErrorContext AKERR_NOIGNORE *akgl_game_save(char *fpath)
{
    FILE *fp = NULL;
    PREPARE_ERROR(errctx);

    ATTEMPT {
	FAIL_ZERO_BREAK(errctx, fpath, AKERR_NULLPOINTER, "NULL file path");
	CATCH(errctx, aksl_fopen(fpath, "wb", &fp));
	CATCH(errctx, aksl_fwrite(&game, 1, sizeof(akgl_Game), fp));
	CATCH(errctx, akgl_game_save_actors(fp));
    } PROCESS(errctx) {
    } CLEANUP {
	if ( fp != NULL )
	    fclose(fp);
    } FINISH(errctx, true);
    SUCCEED_RETURN(errctx); // SUCCEED_NORETURN if in main().
}

akerr_ErrorContext AKERR_NOIGNORE *akgl_game_load_objectnamemap(FILE *fp, SDL_PropertiesID map, int namelength, int ptrlength, SDL_PropertiesID registry)
{
    void *ptr = NULL;
    char ptrstring[32];
    char objname[namelength];
    int retval = 0;
    
    PREPARE_ERROR(errctx);
    while ( 1 ) {
	CATCH(errctx, aksl_fread((void *)&objname, 1, namelength, fp));
	CATCH(errctx, aksl_fread((void *)&ptr, 1, ptrlength, fp));
	// End of the map
	if ( ptr == 0x00 && objname[0] == 0x00 ) {
	    break;
	}
	// The map allows us to say "Object X has a reference to object Y at
	// address Z. The object they had at address Z was named A. Our current
	// instance of object named A is at address B. So we map address Z to
	// address B, so that we can reconnect function pointers on objects loaded
	// from the save game state."
	
	// SDL_Properties objects can only use string keys, so we can't use the
	// old pointer as a key without first converting it to a string.
	CATCH(errctx, aksl_memset((void *)&ptrstring, 0x00, 32));
	snprintf((char *)&ptrstring, 32, "%p", ptr);
	SDL_SetPointerProperty(
	    map,
	    ptrstring,
	    SDL_GetPointerProperty(registry, objname, NULL));
    };
    SUCCEED_RETURN(errctx);
}

akerr_ErrorContext AKERR_NOIGNORE *akgl_game_load_versioncmp(char *versiontype, char *newversion, char *curversion)
{
    semver_t current_version = {};
    semver_t compare_version = {};
    PREPARE_ERROR(errctx);
    FAIL_ZERO_RETURN(errctx, versiontype, AKERR_NULLPOINTER, "NULL argument");
    FAIL_ZERO_RETURN(errctx, curversion, AKERR_NULLPOINTER, "NULL argument");
    FAIL_ZERO_RETURN(errctx, newversion, AKERR_NULLPOINTER, "NULL argument");
    
    ATTEMPT {
	// Check save game library version	
	FAIL_NONZERO_BREAK(
	    errctx,
	    semver_parse((const char *)curversion, &current_version),
	    AKERR_VALUE,
	    "Invalid semantic %s version in current game: %s",
	    versiontype,
	    (char *)curversion);
	FAIL_NONZERO_BREAK(
	    errctx,
	    semver_parse((const char *)newversion, &compare_version),
	    AKERR_VALUE,
	    "Invalid semantic %s version in save game: %s",
	    versiontype,
	    (char *)&newversion);
	FAIL_ZERO_BREAK(
	    errctx,
	    semver_satisfies(compare_version, current_version, "="),
	    AKERR_API,
	    "Incompatible save game %s version (%s != %s)",
	    versiontype,
	    curversion,
	    (char *)&newversion);
    } CLEANUP {
	semver_free(&current_version);
	semver_free(&compare_version);
    } PROCESS(errctx) {
    } FINISH(errctx, true);
    SUCCEED_RETURN(errctx);
}

akerr_ErrorContext AKERR_NOIGNORE *akgl_game_load(char *fpath)
{
    akgl_Game savegame;
    SDL_PropertiesID actormap;
    SDL_PropertiesID spritemap;
    SDL_PropertiesID spritesheetmap;
    SDL_PropertiesID charactermap;
    FILE *fp = NULL;
    
    PREPARE_ERROR(errctx);
    FAIL_ZERO_RETURN(errctx, fpath, AKERR_NULLPOINTER, "NULL file path");
    
    ATTEMPT {
	CATCH(errctx, aksl_fopen(fpath, "rb", &fp));
	CATCH(errctx, aksl_fread((void *)&savegame, 1, sizeof(akgl_Game), fp));
	CATCH(errctx, akgl_game_load_versioncmp("library", (char *)&savegame.libversion, (char *)AKGL_VERSION));
	CATCH(errctx, akgl_game_load_versioncmp("game", (char *)&savegame.version, (char *)&game.version));
	FAIL_NONZERO_RETURN(
	    errctx,
	    strncmp((char *)&savegame.name, (char *)&game.name, 256),
	    AKERR_API,
	    "Savegame is not compatible with this game");
	FAIL_NONZERO_RETURN(
	    errctx,
	    strncmp((char *)&savegame.uri, (char *)&game.uri, 256),
	    AKERR_API,
	    "Savegame is not compatible with this game");
	
	memcpy((void *)&game, (void *)&savegame, sizeof(akgl_Game));
	// Load actor name map
	actormap = SDL_CreateProperties();
	CATCH(errctx, akgl_game_load_objectnamemap(fp, actormap, AKGL_ACTOR_MAX_NAME_LENGTH, sizeof(akgl_Actor *), AKGL_REGISTRY_ACTOR)); 
	// Load sprite name map
	spritemap = SDL_CreateProperties();
	CATCH(errctx, akgl_game_load_objectnamemap(fp, spritemap, AKGL_ACTOR_MAX_NAME_LENGTH, sizeof(akgl_Sprite *), AKGL_REGISTRY_SPRITE)); 
	// Load spritesheet name map
	spritesheetmap = SDL_CreateProperties();
	CATCH(errctx, akgl_game_load_objectnamemap(fp, spritesheetmap, AKGL_ACTOR_MAX_NAME_LENGTH, sizeof(akgl_SpriteSheet *), AKGL_REGISTRY_SPRITESHEET)); 
	// Load character name map
	charactermap = SDL_CreateProperties();
	CATCH(errctx, akgl_game_load_objectnamemap(fp, charactermap, AKGL_ACTOR_MAX_NAME_LENGTH, sizeof(akgl_Character *), AKGL_REGISTRY_CHARACTER)); 
        // Now that we have all of our pointer maps built, we can load the actual binary objects and reset their pointers	
    } CLEANUP {
	if ( fp != NULL ) {
	    fclose(fp);
	}
    } PROCESS(errctx) {
    } FINISH(errctx, true);
    
    SUCCEED_RETURN(errctx);
}