Revert changes in SessionManager

Author: tejasd

firebase-perf/src/main/java/com/google/firebase/perf/session/SessionManager.java

@@ -19,10 +19,11 @@
 import androidx.annotation.Keep;
 import androidx.annotation.VisibleForTesting;
 import com.google.firebase.perf.application.AppStateMonitor;
-import com.google.firebase.perf.application.AppStateUpdateHandler;
 import com.google.firebase.perf.logging.FirebaseSessionsEnforcementCheck;
 import com.google.firebase.perf.session.gauges.GaugeManager;
 import com.google.firebase.perf.v1.ApplicationProcessState;
+import com.google.firebase.perf.v1.GaugeMetadata;
+import com.google.firebase.perf.v1.GaugeMetric;
 import java.lang.ref.WeakReference;
 import java.util.HashSet;
 import java.util.Iterator;
@@ -31,7 +32,7 @@
 
 /** Session manager to generate sessionIDs and broadcast to the application. */
 @Keep // Needed because of b/117526359.
-public class SessionManager extends AppStateUpdateHandler {
+public class SessionManager {
   @SuppressLint("StaticFieldLeak")
   private static final SessionManager instance = new SessionManager();
 
@@ -65,7 +66,6 @@ public SessionManager(
     this.gaugeManager = gaugeManager;
     this.perfSession = perfSession;
     this.appStateMonitor = appStateMonitor;
-    registerForAppState();
   }
 
   /**
@@ -76,21 +76,6 @@ public void setApplicationContext(final Context appContext) {
     gaugeManager.initializeGaugeMetadataManager(appContext);
   }
 
-  @Override
-  public void onUpdateAppState(ApplicationProcessState newAppState) {
-    super.onUpdateAppState(newAppState);
-    if (appStateMonitor.isColdStart()) {
-      // Ignore the app state change if it's a cold start.
-      return;
-    }
-
-    // TODO(b/394127311): Verify if this is called after a new session.
-    if (this.perfSession.isVerbose()) {
-      long collectionFrequency = updateGaugeCollection(newAppState);
-      updateGaugeLogging(perfSession.sessionId(), newAppState, collectionFrequency);
-    }
-  }
-
   /**
    * Checks if the current {@link PerfSession} is expired/timed out. If so, stop collecting gauges.
    *
@@ -107,10 +92,12 @@ public void stopGaugeCollectionIfSessionRunningTooLong() {
   }
 
   /**
-   * Updates the currently associated {@link #perfSession} and broadcast the change to relevant
-   * traces.
+   * Updates the currently associated {@link #perfSession} and broadcast the change.
+   *
+   * <p>Uses the provided PerfSession {@link PerfSession}, log the {@link GaugeMetadata} and
+   * start/stop the collection of {@link GaugeMetric} depending upon Session verbosity.
    *
-   * <p>Uses the provided PerfSession {@link PerfSession}.
+   * @see PerfSession#isVerbose()
    */
   public void updatePerfSession(PerfSession perfSession) {
     // Do not update the perf session if it is the exact same sessionId.
@@ -119,6 +106,9 @@ public void updatePerfSession(PerfSession perfSession) {
     }
 
     this.perfSession = perfSession;
+
+    // TODO(b/394127311): Update/verify behavior for Firebase Sessions.
+
     synchronized (clients) {
       for (Iterator<WeakReference<SessionAwareObject>> i = clients.iterator(); i.hasNext(); ) {
         SessionAwareObject callback = i.next().get();
@@ -131,6 +121,9 @@ public void updatePerfSession(PerfSession perfSession) {
         }
       }
     }
+
+    // Start of stop the gauge data collection.
+    startOrStopCollectingGauges(appStateMonitor.getAppState());
   }
 
   /**
@@ -140,16 +133,7 @@ public void updatePerfSession(PerfSession perfSession) {
    * this does not reset the perfSession.
    */
   public void initializeGaugeCollection() {
-    if (perfSession.isVerbose()) {
-      updateGaugeCollection(ApplicationProcessState.FOREGROUND);
-    }
-  }
-
-  public void updateGaugeCollectionOnNewSession() {
-    if (perfSession.isVerbose()) {
-      long frequency = updateGaugeCollection(ApplicationProcessState.FOREGROUND);
-      updateGaugeLogging(perfSession.sessionId(), ApplicationProcessState.FOREGROUND, frequency);
-    }
+    startOrStopCollectingGauges(ApplicationProcessState.FOREGROUND);
   }
 
   /**
@@ -176,13 +160,15 @@ public void unregisterForSessionUpdates(WeakReference<SessionAwareObject> client
     }
   }
 
-  private long updateGaugeCollection(ApplicationProcessState applicationProcessState) {
-    return gaugeManager.updateGaugeCollection(applicationProcessState, perfSession.getTimer());
-  }
+  private void startOrStopCollectingGauges(ApplicationProcessState appState) {
+    FirebaseSessionsEnforcementCheck.checkSession(
+        perfSession, "Session is not ready while trying to startOrStopCollectingGauges");
 
-  private void updateGaugeLogging(
-      String sessionId, ApplicationProcessState applicationProcessState, long collectionFrequency) {
-    gaugeManager.updateGaugeLogging(sessionId, applicationProcessState, collectionFrequency);
+    if (perfSession.isGaugeAndEventCollectionEnabled()) {
+      gaugeManager.startCollectingGauges(perfSession, appState);
+    } else {
+      gaugeManager.stopCollectingGauges();
+    }
   }
 
   @VisibleForTesting