Refactor

src/main/kotlin/eventDemo/libs/event/EventStreamInMemory.kt

@@ -0,0 +1,43 @@
+package eventDemo.libs.event
+
+import io.github.oshai.kotlinlogging.KotlinLogging
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.flow
+import kotlin.reflect.KClass
+
+abstract class EventStreamInMemory<E : Event<ID>, ID : AggregateId>(
+    private val eventType: Class<E>,
+) : EventStream<E, ID> {
+    private val logger = KotlinLogging.logger {}
+    private val eventBus: MutableList<E> = mutableListOf()
+
+    override fun publish(event: E) {
+        eventBus.add(event)
+        logger.atInfo {
+            message = "Event published: $event"
+            payload = mapOf("event" to event)
+        }
+    }
+
+    override fun publish(vararg events: E) {
+        events.forEach { publish(it) }
+    }
+
+    override fun readLast(aggregateId: ID): E? = eventBus.lastOrNull()
+
+    override fun <R : E> readLastOf(
+        aggregateId: ID,
+        eventType: KClass<out R>,
+    ): R? =
+        eventBus
+            .filterIsInstance(eventType.java)
+            .lastOrNull { it.id == aggregateId }
+
+    override fun readAll(aggregateId: ID): Flow<E> =
+        flow {
+            eventBus.forEach { emit(it) }
+        }
+}
+
+inline fun <reified R : E, E : Event<ID>, ID : AggregateId> EventStreamInMemory<E, ID>.readLastOf(aggregateId: ID): R? =
+    readLastOf(aggregateId, R::class)