1 files changed, 42 insertions, 0 deletions
diff --git a/composeApp/src/commonMain/kotlin/coffee/liz/ecs/World.kt b/composeApp/src/commonMain/kotlin/coffee/liz/ecs/World.kt
new file mode 100644
index 0000000..fd3b6df
--- /dev/null
+++ b/composeApp/src/commonMain/kotlin/coffee/liz/ecs/World.kt
@@ -0,0 +1,42 @@
+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)