4 files changed, 88 insertions, 0 deletions
diff --git a/android/src/main/kotlin/net/mullvad/mullvadvpn/MullvadDaemon.kt b/android/src/main/kotlin/net/mullvad/mullvadvpn/MullvadDaemon.kt
index 9de3dc12d7..751334ea61 100644
--- a/android/src/main/kotlin/net/mullvad/mullvadvpn/MullvadDaemon.kt
+++ b/android/src/main/kotlin/net/mullvad/mullvadvpn/MullvadDaemon.kt
@@ -1,6 +1,7 @@
 package net.mullvad.mullvadvpn
 
 import net.mullvad.mullvadvpn.model.AccountData
+import net.mullvad.mullvadvpn.model.AppVersionInfo
 import net.mullvad.mullvadvpn.model.GeoIpLocation
 import net.mullvad.mullvadvpn.model.KeygenEvent
 import net.mullvad.mullvadvpn.model.PublicKey
@@ -29,6 +30,7 @@ class MullvadDaemon(val vpnService: MullvadVpnService) {
     external fun getRelayLocations(): RelayList
     external fun getSettings(): Settings
     external fun getState(): TunnelState
+    external fun getVersionInfo(): AppVersionInfo?
     external fun getWireguardKey(): PublicKey?
     external fun setAccount(accountToken: String?)
     external fun updateRelaySettings(update: RelaySettingsUpdate)
diff --git a/android/src/main/kotlin/net/mullvad/mullvadvpn/MullvadVpnService.kt b/android/src/main/kotlin/net/mullvad/mullvadvpn/MullvadVpnService.kt
index bc0c317cf2..6cb45329ff 100644
--- a/android/src/main/kotlin/net/mullvad/mullvadvpn/MullvadVpnService.kt
+++ b/android/src/main/kotlin/net/mullvad/mullvadvpn/MullvadVpnService.kt
@@ -15,15 +15,19 @@ import android.net.VpnService
 import android.os.Binder
 import android.os.IBinder
 
+import net.mullvad.mullvadvpn.dataproxy.AppVersionInfoFetcher
 import net.mullvad.mullvadvpn.model.TunConfig
 
 class MullvadVpnService : VpnService() {
     private val created = CompletableDeferred<Unit>()
     private val binder = LocalBinder()
 
+    private lateinit var versionInfoFetcher: AppVersionInfoFetcher
+
     val daemon = startDaemon()
 
     override fun onCreate() {
+        versionInfoFetcher = AppVersionInfoFetcher(daemon, this)
         created.complete(Unit)
     }
 
@@ -32,6 +36,7 @@ class MullvadVpnService : VpnService() {
     }
 
     override fun onDestroy() {
+        versionInfoFetcher.stop()
         daemon.cancel()
         created.cancel()
     }
diff --git a/android/src/main/kotlin/net/mullvad/mullvadvpn/dataproxy/AppVersionInfoFetcher.kt b/android/src/main/kotlin/net/mullvad/mullvadvpn/dataproxy/AppVersionInfoFetcher.kt
new file mode 100644
index 0000000000..2b066c934b
--- /dev/null
+++ b/android/src/main/kotlin/net/mullvad/mullvadvpn/dataproxy/AppVersionInfoFetcher.kt
@@ -0,0 +1,74 @@
+package net.mullvad.mullvadvpn.dataproxy
+
+import java.util.Calendar
+
+import kotlinx.coroutines.delay
+import kotlinx.coroutines.launch
+import kotlinx.coroutines.Deferred
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.GlobalScope
+
+import android.content.Context
+
+import net.mullvad.mullvadvpn.MullvadDaemon
+
+val ONE_DAY_IN_MILLISECONDS = 24L * 60L * 60L * 1000L
+val ONE_MINUTE_IN_MILLISECONDS = 60L * 1000L
+
+val KEY_CURRENT_IS_SUPPORTED = "current_is_supported"
+val KEY_LAST_UPDATED = "last_updated"
+val KEY_LATEST_STABLE = "latest_stable"
+val KEY_LATEST = "latest"
+val SHARED_PREFERENCES = "app_version_info_cache"
+
+class AppVersionInfoFetcher(val daemon: Deferred<MullvadDaemon>, val context: Context) {
+    private val preferences = context.getSharedPreferences(SHARED_PREFERENCES, Context.MODE_PRIVATE)
+
+    private val mainLoop = run()
+
+    fun stop() {
+        mainLoop.cancel()
+    }
+
+    private fun run() = GlobalScope.launch(Dispatchers.Default) {
+        while (true) {
+            delay(calculateDelay())
+            fetch()
+        }
+    }
+
+    private fun calculateDelay(): Long {
+        val now = Calendar.getInstance().timeInMillis
+        val lastUpdated = preferences.getLong(KEY_LAST_UPDATED, 0)
+        val delta = now - lastUpdated
+
+        if (delta < 0 || delta >= ONE_DAY_IN_MILLISECONDS) {
+            return 0
+        } else {
+            return ONE_DAY_IN_MILLISECONDS - delta
+        }
+    }
+
+    private suspend fun fetch() {
+        var now = Calendar.getInstance().timeInMillis
+        var versionInfo = daemon.await().getVersionInfo()
+        var attempt = 0
+
+        while (attempt < 5 && versionInfo == null) {
+            delay(ONE_MINUTE_IN_MILLISECONDS)
+            now = Calendar.getInstance().timeInMillis
+            versionInfo = daemon.await().getVersionInfo()
+            attempt += 1
+        }
+
+        if (versionInfo != null) {
+            preferences.edit().apply {
+                putLong(KEY_LAST_UPDATED, now)
+                putBoolean(KEY_CURRENT_IS_SUPPORTED, versionInfo.currentIsSupported)
+                putString(KEY_LATEST_STABLE, versionInfo.latestStable)
+                putString(KEY_LATEST, versionInfo.latest)
+                commit()
+            }
+        }
+    }
+}
diff --git a/android/src/main/kotlin/net/mullvad/mullvadvpn/model/AppVersionInfo.kt b/android/src/main/kotlin/net/mullvad/mullvadvpn/model/AppVersionInfo.kt
new file mode 100644
index 0000000000..0c41090f3f
--- /dev/null
+++ b/android/src/main/kotlin/net/mullvad/mullvadvpn/model/AppVersionInfo.kt
@@ -0,0 +1,7 @@
+package net.mullvad.mullvadvpn.model
+
+data class AppVersionInfo(
+    val currentIsSupported: Boolean,
+    val latestStable: String,
+    val latest: String
+)