Create `AppVersionInfoFetcher`

1 files changed, 74 insertions, 0 deletions

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()
+            }
+        }
+    }
+}