fixup! Bug 40028: Implement Tor Service controller

Define enum class for tor's status and define current state using
the enums.

app/src/main/java/org/mozilla/fenix/tor/TorController.kt

@@ -30,6 +30,31 @@ interface TorEvents {
     fun onTorStopped()
 }
 
+private enum class TorStatus {
+    OFF,
+    STARTING,
+    ON,
+    STOPPING,
+    UNKNOWN;
+
+    fun getStateFromString(status: String) : TorStatus{
+        return when (status) {
+            TorServiceConstants.STATUS_ON -> ON
+            TorServiceConstants.STATUS_STARTING -> STARTING
+            TorServiceConstants.STATUS_STOPPING -> STOPPING
+            TorServiceConstants.STATUS_OFF -> OFF
+            else -> UNKNOWN
+        }
+    }
+
+    fun isOff() = this == OFF
+    fun isOn() = this == ON
+    fun isStarting() = this == STARTING
+    fun isStarted() = ((this == TorStatus.STARTING) || (this == TorStatus.ON))
+    fun isStopping() = this == STOPPING
+    fun isUnknown() = this == UNKNOWN
+}
+
 class TorController(
     private val context: Context
 ) : TorEvents {
@@ -43,15 +68,23 @@ class TorController(
     private var pendingRegisterChangeList = mutableListOf<Pair<TorEvents, Boolean>>()
     private var lockTorListenersMutation = false
 
-    private var isTorStarted = false
+    private var lastKnownStatus = TorStatus.OFF
+    private var wasTorBootstrapped = false
+    private var isTorRestarting = false
+
+    // This may be a lie
     private var isTorBootstrapped = false
+        get() = ((lastKnownStatus == TorStatus.ON) && wasTorBootstrapped)
 
     val isDebugLoggingEnabled get() =
         context.
         getSharedPreferences("org.torproject.android_preferences", Context.MODE_PRIVATE).
         getBoolean("pref_enable_logging", false)
 
+    val isStarting get() = lastKnownStatus.isStarting()
+    val isRestarting get() = isTorRestarting
     val isBootstrapped get() = isTorBootstrapped
+    val isConnected get() = (lastKnownStatus.isStarted() && !isTorRestarting)
 
     fun start() {
         // Register receiver
@@ -93,22 +126,41 @@ class TorController(
                 return
             }
 
-            entries.add(Pair(logentry, status))
-
             onTorStatusUpdate(logentry, status)
-            if (status != null && status.startsWith("ON")) {
-                isTorStarted = true
+
+            if (status == null) {
+                return
             }
 
+            val newStatus = lastKnownStatus.getStateFromString(status)
+
+            if (newStatus.isUnknown()) {
+                if (wasTorBootstrapped) {
+                    stopTor()
+                }
+            }
+
+            entries.add(Pair(logentry, status))
+
             if (logentry != null && logentry.contains(TorServiceConstants.TOR_CONTROL_PORT_MSG_BOOTSTRAP_DONE)) {
-                isTorBootstrapped = true
+                wasTorBootstrapped = true
                 onTorConnected()
             }
 
-            if (isTorStarted && status != null && status.startsWith("OFF")) {
-                setTorStopped()
+            if (lastKnownStatus.isStopping() && newStatus.isOff()) {
+                if (isTorRestarting) {
+                    initiateTorBootstrap()
+                } else {
+                    onTorStopped()
                 }
             }
+
+            if (lastKnownStatus.isOff() && newStatus.isStarting()) {
+                isTorRestarting = false
+            }
+
+            lastKnownStatus = newStatus
+        }
     }
 
     override fun onTorConnecting() {
@@ -251,8 +303,7 @@ class TorController(
     }
 
     fun setTorStopped() {
-        isTorStarted = false
-        isTorBootstrapped = false
+        lastKnownStatus = TorStatus.OFF
         onTorStopped()
     }
 
@@ -265,12 +316,15 @@ class TorController(
             return
         }
 
-        isTorRestarting = true
         if (!lastKnownStatus.isStarted() && wasTorBootstrapped) {
             // If we aren't started, but we were previously bootstrapped,
             // then we handle a "restart" request as a "start" restart
             initiateTorBootstrap()
         } else {
+            // |isTorRestarting| tracks the state of restart. When we receive an |OFF| state
+            // from TorService in persistentBroadcastReceiver::onReceive we restart the Tor
+            // service.
+            isTorRestarting = true
             stopTor()
         }
     }