#include "../chapter/chapter_0.c"
#include "../chapter/chapter_1.c"
#include "../chapter/chapter_2.c"

static int  entity_define (char * name, int character, int colour, int effect, int value, int logic, void (* trigger) (void));
static void entity_create (int entity, int amount);
static void entity_render (int entity);

static void entity_clean_up     (void);
static void entity_update_logic (void);

static int player_x     = 0;
static int player_y     = 0;
static int player_coins = 0;

static int      entity_count     = 0;
static char * * entity_name      = NULL;
static char   * entity_character = '\0';
static int    * entity_colour    = 0;
static int    * entity_effect    = 0;
static int    * entity_value     = 0;
static int    * entity_logic     = 0;

static void (* * entity_trigger) (void) = NULL;

static int   entity_usage     = 0;
static int * entity_index     = 0;
static int * entity_x         = 0;
static int * entity_y         = 0;

static void player_move_up    (void) { player_y -= 1; limit (& player_y, 0, curses_screen_height - 1); }
static void player_move_down  (void) { player_y += 1; limit (& player_y, 0, curses_screen_height - 1); }
static void player_move_left  (void) { player_x -= 1; limit (& player_x, 0, curses_screen_width  - 1); }
static void player_move_right (void) { player_x += 1; limit (& player_x, 0, curses_screen_width  - 1); }
static void player_take_coin  (void) { ++player_coins;                                                 }
static void player_died       (void) { curses_active = 0;                                              }

int main (void) {
	terminal_show_cursor (FALSE);

	curses_configure ();

	curses_bind (SIGNAL_W, player_move_up);
	curses_bind (SIGNAL_S, player_move_down);
	curses_bind (SIGNAL_A, player_move_left);
	curses_bind (SIGNAL_D, player_move_right);

	int coin       = entity_define ("Coin",       '+', COLOUR_YELLOW, EFFECT_BOLD,   1, FALSE, player_take_coin);
	int goblin     = entity_define ("Goblin",     'g', COLOUR_RED,    EFFECT_NORMAL, 3, TRUE,  player_died);
	int hob_goblin = entity_define ("Hob Goblin", 'G', COLOUR_RED,    EFFECT_BOLD,   7, TRUE,  player_died);

	entity_create (coin,       11);
	entity_create (goblin,      7);
	entity_create (hob_goblin,  3);

	while (curses_active) {
		curses_render_background ('.', COLOUR_GREY, EFFECT_BOLD);

		curses_render_rectangle_fill (',', COLOUR_GREEN, EFFECT_NORMAL, 10, 10, 80, 24);
		curses_render_rectangle_line ('#', COLOUR_WHITE, EFFECT_NORMAL, 10, 10, 80, 24);

		for (int entity = 0; entity < entity_usage; ++entity) {
			entity_render (entity);
		}

		curses_render_character ('@', COLOUR_CYAN, EFFECT_BOLD, player_x, player_y);

		curses_render_number (player_coins, COLOUR_YELLOW, EFFECT_BOLD, 0, 0);

		entity_update_logic ();

		curses_synchronize ();
	}

	entity_clean_up ();

	terminal_show_cursor (TRUE);

	return (EXIT_SUCCESS);
}

static int entity_define (char * name, int character, int colour, int effect, int value, int logic, void (* trigger) (void)) {
	int entity = entity_count;

	++entity_count;

	entity_name      = reallocate (entity_name,      entity_count * (int) sizeof (* entity_name));
	entity_character = reallocate (entity_character, entity_count * (int) sizeof (* entity_character));
	entity_colour    = reallocate (entity_colour,    entity_count * (int) sizeof (* entity_colour));
	entity_effect    = reallocate (entity_effect,    entity_count * (int) sizeof (* entity_effect));
	entity_value     = reallocate (entity_value,     entity_count * (int) sizeof (* entity_value));
	entity_logic     = reallocate (entity_logic,     entity_count * (int) sizeof (* entity_logic));
	entity_trigger   = reallocate (entity_trigger,   entity_count * (int) sizeof (* entity_trigger));

	string_copy ((entity_name [entity] = allocate (string_length (name) + 1)), name);

	entity_character [entity] = character;
	entity_colour    [entity] = colour;
	entity_effect    [entity] = effect;
	entity_value     [entity] = value;
	entity_logic     [entity] = logic;
	entity_trigger   [entity] = trigger;

	return (entity);
}

static void entity_create (int entity, int amount) {
	int index;

	for (index = 0; index < amount; ++index) {
		++entity_usage;

		entity_index = reallocate (entity_index, entity_usage * (int) sizeof (* entity_index));
		entity_x     = reallocate (entity_x,     entity_usage * (int) sizeof (* entity_x));
		entity_y     = reallocate (entity_y,     entity_usage * (int) sizeof (* entity_y));

		entity_index [entity_usage - 1] = entity;
		entity_x     [entity_usage - 1] = randomize (0, curses_screen_width  - 1);
		entity_y     [entity_usage - 1] = randomize (0, curses_screen_height - 1);
	}
}

static void entity_render (int entity) {
	if (entity_index [entity] == -1) {
		return;
	}

	curses_render_character (entity_character [entity_index [entity]],
	                         entity_colour    [entity_index [entity]],
	                         entity_effect    [entity_index [entity]],
	                         entity_x         [entity],
	                         entity_y         [entity]);
}

void entity_clean_up (void) {
	for (int entity = 0; entity < entity_count; ++entity) {
		entity_name [entity] = deallocate (entity_name [entity]);
	}

	entity_name      = deallocate (entity_name);
	entity_character = deallocate (entity_character);
	entity_colour    = deallocate (entity_colour);
	entity_effect    = deallocate (entity_effect);
	entity_value     = deallocate (entity_value);
	entity_logic     = deallocate (entity_logic);
	entity_trigger   = deallocate (entity_trigger);
	entity_index     = deallocate (entity_index);
	entity_x         = deallocate (entity_x);
	entity_y         = deallocate (entity_y);

	entity_count = 0;
	entity_usage = 0;
}

void entity_update_logic (void) {
	for (int entity = 0; entity < entity_usage; ++entity) {
		if (entity_index [entity] == -1) {
			continue;
		}

		if (entity_logic [entity_index [entity]] == TRUE) {
			entity_x [entity] += randomize (0, 1) * ((randomize (0, 1) == 0) ? +1 : -1);
			entity_y [entity] += randomize (0, 1) * ((randomize (0, 1) == 0) ? +1 : -1);

			limit (& entity_x [entity], 0, curses_screen_width  - 1);
			limit (& entity_y [entity], 0, curses_screen_height - 1);
		}

		if ((player_x == entity_x [entity]) && (player_y == entity_y [entity])) {
			if (entity_trigger [entity_index [entity]] != NULL) {
				entity_trigger [entity_index [entity]] ();
			}

			entity_index [entity] = -1;
		}
	}
}