Allow listening for `TunnelState` persistence

2 files changed, 52 insertions, 0 deletions

diff --git a/android/src/main/kotlin/net/mullvad/mullvadvpn/service/tunnelstate/Persistence.kt b/android/src/main/kotlin/net/mullvad/mullvadvpn/service/tunnelstate/Persistence.kt
index c3d3be36c0..f1366abc66 100644
--- a/android/src/main/kotlin/net/mullvad/mullvadvpn/service/tunnelstate/Persistence.kt
+++ b/android/src/main/kotlin/net/mullvad/mullvadvpn/service/tunnelstate/Persistence.kt
@@ -1,6 +1,7 @@
 package net.mullvad.mullvadvpn.service.tunnelstate
 
 import android.content.Context
+import android.content.SharedPreferences.OnSharedPreferenceChangeListener
 import java.net.InetSocketAddress
 import net.mullvad.mullvadvpn.model.TunnelState
 import net.mullvad.talpid.net.Endpoint
@@ -26,6 +27,21 @@ internal class Persistence(context: Context) {
             persistState(value)
         }
 
+    var listener: OnSharedPreferenceChangeListener? = null
+        set(value) {
+            if (value != field) {
+                if (field != null) {
+                    sharedPreferences.unregisterOnSharedPreferenceChangeListener(field)
+                }
+
+                if (value != null) {
+                    sharedPreferences.registerOnSharedPreferenceChangeListener(value)
+                }
+
+                field = value
+            }
+        }
+
     private fun loadState(): TunnelState {
         val description = sharedPreferences.getString(KEY_TUNNEL_STATE, TunnelState.DISCONNECTED)!!
 
diff --git a/android/src/main/kotlin/net/mullvad/mullvadvpn/service/tunnelstate/TunnelStateListener.kt b/android/src/main/kotlin/net/mullvad/mullvadvpn/service/tunnelstate/TunnelStateListener.kt
new file mode 100644
index 0000000000..7f7832d3e4
--- /dev/null
+++ b/android/src/main/kotlin/net/mullvad/mullvadvpn/service/tunnelstate/TunnelStateListener.kt
@@ -0,0 +1,36 @@
+package net.mullvad.mullvadvpn.service.tunnelstate
+
+import android.content.Context
+import android.content.SharedPreferences
+import android.content.SharedPreferences.OnSharedPreferenceChangeListener
+import net.mullvad.mullvadvpn.model.TunnelState
+
+class TunnelStateListener(context: Context) {
+    private val persistence = Persistence(context)
+
+    private val listener = object : OnSharedPreferenceChangeListener {
+        override fun onSharedPreferenceChanged(preferences: SharedPreferences, key: String) {
+            state = persistence.state
+        }
+    }
+
+    var state = persistence.state
+        private set(value) {
+            if (field != value) {
+                field = value
+                onStateChange?.invoke(value)
+            }
+        }
+
+    var onStateChange: ((TunnelState) -> Unit)? = null
+        set(value) {
+            field = value
+
+            if (value == null) {
+                persistence.listener = null
+            } else {
+                persistence.listener = listener
+                state = persistence.state
+            }
+        }
+}