Minimizes costs of keeping track of the number of events received per subscription

app/src/main/java/com/vitorpamplona/amethyst/service/NostrDataSource.kt

@@ -43,9 +43,9 @@ abstract class NostrDataSource(val debugName: String) {
 
     private var subscriptions = mapOf<String, Subscription>()
 
-    data class Counter(var counter: Int)
+    data class Counter(val subscriptionId: String, val eventKind: Int, var counter: Int)
 
-    private var eventCounter = mapOf<String, Counter>()
+    private var eventCounter = mapOf<Int, Counter>()
     var changingFilters = AtomicBoolean()
 
     private var active: Boolean = false
@@ -54,11 +54,18 @@ abstract class NostrDataSource(val debugName: String) {
         eventCounter.forEach {
             Log.d(
                 "STATE DUMP ${this.javaClass.simpleName}",
-                "Received Events ${it.key}: ${it.value.counter}",
+                "Received Events $debugName ${it.value.subscriptionId} ${it.value.eventKind}: ${it.value.counter}",
             )
         }
     }
 
+    fun hashCodeFields(
+        str1: String,
+        str2: Int,
+    ): Int {
+        return 31 * str1.hashCode() + str2.hashCode()
+    }
+
     private val clientListener =
         object : Client.Listener() {
             override fun onEvent(
@@ -68,12 +75,12 @@ abstract class NostrDataSource(val debugName: String) {
                 afterEOSE: Boolean,
             ) {
                 if (subscriptions.containsKey(subscriptionId)) {
-                    val key = "$debugName $subscriptionId ${event.kind}"
-                    val keyValue = eventCounter.get(key)
+                    val key = hashCodeFields(subscriptionId, event.kind)
+                    val keyValue = eventCounter[key]
                     if (keyValue != null) {
                         keyValue.counter++
                     } else {
-                        eventCounter = eventCounter + Pair(key, Counter(1))
+                        eventCounter = eventCounter + Pair(key, Counter(subscriptionId, event.kind, 1))
                     }
 
                     // Log.d(this@NostrDataSource.javaClass.simpleName, "Relay ${relay.url}: ${event.kind}")