/*
 * Game plugin.
 *
 * A game plugin exposes three functions:
 * - boot(): called once when the plugin is first loaded during the lifetime of
 * the game.
 * - init() -> state: creates and returns the plugin's state.
 * - update(state): takes and updates the state, possibly with side effects.
 * - render(): performs custom rendering.
 *
 * boot() is convenient for one-time initialization of the scene.
 *
 * init() is called every time the plugin is loaded. It is assumed that the
 * plugin's state is encapsulated in the object returned.
 *
 * update() updates the plugin state and has side effects on the scene. It is
 * assumed that update does not reference any global, mutable state outside of
 * the scene and the plugin state returned by init().
 */
#pragma once

#include "../game.h"

#include <gfx/gfx.h>
#include <gfx/scene.h>

#include <stdbool.h>

typedef struct State State;

/// Initialize the plugin's state.
State* init(Game*);

/// Function called the first time the plugin is loaded throughout the
/// application's lifetime. Allows the plugin to do one-time initialization of
/// the game state.
bool boot(State*, Game*);

/// Update the plugin's and the game's state.
void update(State*, Game*, double t, double dt);

/// Optional plugin rendering hook.
void render(State*, const Game*);

// Signatures for the plugin's exposed functions.
typedef void* (*plugin_init)(Game*);
typedef bool (*plugin_boot)(State*, Game*);
typedef void (*plugin_update)(State*, Game*, double t, double dt);
typedef void (*plugin_render)(State*, const Game*);