package coffee.liz.ecs

import kotlin.jvm.JvmName
import kotlin.reflect.KClass

/**
 * The World manages entities and systems.
 */
interface World {
    /**
     * Create a new entity with a unique ID.
     */
    fun createEntity(): Entity

    /**
     * Destroy an entity and remove it from all caches.
     */
    fun destroyEntity(entity: Entity)

    /**
     * Get all entities that have all the specified component types.
     */
    fun query(vararg componentTypes: KClass<out Component>): Set<Entity>

    /**
     * Update all systems in dependency order.
     * @param deltaTime Time elapsed since last update in seconds
     */
    fun update(deltaTime: Float)
}

// Convenience extension for queries
@JvmName("query1")
inline fun <reified T : Component> World.query(): Set<Entity> = query(T::class)

@JvmName("query2")
inline fun <reified T1 : Component, reified T2 : Component> World.query(): Set<Entity> =
    query(T1::class, T2::class)

@JvmName("query3")
inline fun <reified T1 : Component, reified T2 : Component, reified T3 : Component> World.query(): Set<Entity> =
    query(T1::class, T2::class, T3::class)