Implement ConstantLookup

mobile/src/main/java/be/mygod/vpnhotspot/manage/TetherManager.kt

@@ -88,7 +88,7 @@ sealed class TetherManager(protected val parent: TetheringFragment) : Manager(),
     override fun onTetheringStarted() = data.notifyChange()
     override fun onTetheringFailed(error: Int?) {
         Timber.d("onTetheringFailed: $error")
-        error?.let { SmartSnackbar.make("$tetherType: ${TetheringManager.tetherErrorMessage(it)}").show() }
+        error?.let { SmartSnackbar.make("$tetherType: ${TetheringManager.tetherErrorLookup(it)}").show() }
         data.notifyChange()
     }
     override fun onException(e: Exception) {
@@ -108,7 +108,7 @@ sealed class TetherManager(protected val parent: TetheringFragment) : Manager(),
         val interested = errored.filter { TetherType.ofInterface(it) == tetherType }
         baseError = if (interested.isEmpty()) null else interested.joinToString("\n") { iface ->
             "$iface: " + try {
-                TetheringManager.tetherErrorMessage(TetheringManager.getLastTetherError(iface))
+                TetheringManager.tetherErrorLookup(TetheringManager.getLastTetherError(iface))
             } catch (e: InvocationTargetException) {
                 if (Build.VERSION.SDK_INT !in 24..25 || e.cause !is SecurityException) Timber.w(e) else Timber.d(e)
                 e.readableMessage
@@ -149,7 +149,7 @@ sealed class TetherManager(protected val parent: TetheringFragment) : Manager(),
         override val title get() = parent.getString(R.string.tethering_manage_wifi)
         override val tetherType get() = TetherType.WIFI
         override val type get() = VIEW_TYPE_WIFI
-        override val text get() = listOfNotNull(failureReason?.let { WifiApManager.failureReason(it) },
+        override val text get() = listOfNotNull(failureReason?.let { WifiApManager.failureReasonLookup(it) },
                 baseError).joinToString("\n")
 
         override fun start() = TetheringManager.startTethering(TetheringManager.TETHERING_WIFI, true, this)

mobile/src/main/java/be/mygod/vpnhotspot/manage/TetheringTileService.kt

@@ -118,7 +118,7 @@ sealed class TetheringTileService : IpNeighbourMonitoringTileService(), Tetherin
     override fun onTetheringStarted() = updateTile()
     override fun onTetheringFailed(error: Int?) {
         Timber.d("onTetheringFailed: $error")
-        error?.let { Toast.makeText(this, TetheringManager.tetherErrorMessage(it), Toast.LENGTH_LONG).show() }
+        error?.let { Toast.makeText(this, TetheringManager.tetherErrorLookup(it), Toast.LENGTH_LONG).show() }
         updateTile()
     }
     override fun onException(e: Exception) {

mobile/src/main/java/be/mygod/vpnhotspot/net/TetheringManager.kt

@@ -12,9 +12,7 @@ import android.net.Network
 import android.os.Build
 import android.os.Handler
 import androidx.annotation.RequiresApi
-import androidx.collection.SparseArrayCompat
 import be.mygod.vpnhotspot.App.Companion.app
-import be.mygod.vpnhotspot.R
 import be.mygod.vpnhotspot.root.RootManager
 import be.mygod.vpnhotspot.root.StartTethering
 import be.mygod.vpnhotspot.root.StopTethering
@@ -607,31 +605,12 @@ object TetheringManager {
      */
     fun getLastTetherError(iface: String): Int = getLastTetherError(Services.connectivity, iface) as Int
 
-    // tether errors defined in ConnectivityManager up to Android 10
+    val tetherErrorLookup = ConstantLookup(clazz, "TETHER_ERROR_",
-    private val tetherErrors29 = arrayOf("TETHER_ERROR_NO_ERROR", "TETHER_ERROR_UNKNOWN_IFACE",
+            "TETHER_ERROR_NO_ERROR", "TETHER_ERROR_UNKNOWN_IFACE", "TETHER_ERROR_SERVICE_UNAVAIL",
-            "TETHER_ERROR_SERVICE_UNAVAIL", "TETHER_ERROR_UNSUPPORTED", "TETHER_ERROR_UNAVAIL_IFACE",
+            "TETHER_ERROR_UNSUPPORTED", "TETHER_ERROR_UNAVAIL_IFACE", "TETHER_ERROR_MASTER_ERROR",
-            "TETHER_ERROR_MASTER_ERROR", "TETHER_ERROR_TETHER_IFACE_ERROR", "TETHER_ERROR_UNTETHER_IFACE_ERROR",
+            "TETHER_ERROR_TETHER_IFACE_ERROR", "TETHER_ERROR_UNTETHER_IFACE_ERROR", "TETHER_ERROR_ENABLE_NAT_ERROR",
-            "TETHER_ERROR_ENABLE_NAT_ERROR", "TETHER_ERROR_DISABLE_NAT_ERROR", "TETHER_ERROR_IFACE_CFG_ERROR",
+            "TETHER_ERROR_DISABLE_NAT_ERROR", "TETHER_ERROR_IFACE_CFG_ERROR", "TETHER_ERROR_PROVISION_FAILED",
-            "TETHER_ERROR_PROVISION_FAILED", "TETHER_ERROR_DHCPSERVER_ERROR", "TETHER_ERROR_ENTITLEMENT_UNKNOWN")
+            "TETHER_ERROR_DHCPSERVER_ERROR", "TETHER_ERROR_ENTITLEMENT_UNKNOWN")
-    @get:RequiresApi(30)
-    private val tetherErrors by lazy {
-        SparseArrayCompat<String>().apply {
-            for (field in clazz.declaredFields) try {
-                // all TETHER_ERROR_* are system-api since API 30
-                if (field.name.startsWith("TETHER_ERROR_")) put(field.get(null) as Int, field.name)
-            } catch (e: Exception) {
-                Timber.w(e)
-            }
-        }
-    }
-    fun tetherErrorMessage(error: Int): String {
-        if (Build.VERSION.SDK_INT >= 30) try {
-            tetherErrors.get(error)?.let { return it }
-        } catch (e: ReflectiveOperationException) {
-            Timber.w(e)
-        }
-        return tetherErrors29.getOrNull(error) ?: app.getString(R.string.failure_reason_unknown, error)
-    }
 
     val Intent.tetheredIfaces get() = getStringArrayListExtra(
             if (Build.VERSION.SDK_INT >= 26) EXTRA_ACTIVE_TETHER else EXTRA_ACTIVE_TETHER_LEGACY)

mobile/src/main/java/be/mygod/vpnhotspot/net/wifi/WifiApManager.kt

@@ -8,15 +8,12 @@ import android.net.wifi.SoftApConfiguration
 import android.net.wifi.WifiManager
 import android.os.Build
 import android.os.Handler
-import android.os.Looper
 import androidx.annotation.RequiresApi
-import androidx.collection.SparseArrayCompat
 import be.mygod.vpnhotspot.App.Companion.app
-import be.mygod.vpnhotspot.R
 import be.mygod.vpnhotspot.net.wifi.SoftApConfigurationCompat.Companion.toCompat
+import be.mygod.vpnhotspot.util.ConstantLookup
 import be.mygod.vpnhotspot.util.Services
 import be.mygod.vpnhotspot.util.callSuper
-import be.mygod.vpnhotspot.util.makeExecutor
 import timber.log.Timber
 import java.lang.reflect.InvocationHandler
 import java.lang.reflect.Method
@@ -96,25 +93,8 @@ object WifiApManager {
         @RequiresApi(30)
         fun onBlockedClientConnecting(client: MacAddress, blockedReason: Int) { }
     }
-    private val startFailures29 = arrayOf("SAP_START_FAILURE_GENERAL", "SAP_START_FAILURE_NO_CHANNEL")
+    val failureReasonLookup = ConstantLookup<WifiManager>("SAP_START_FAILURE_",
-    private val startFailures by lazy {
+            "SAP_START_FAILURE_GENERAL", "SAP_START_FAILURE_NO_CHANNEL")
-        SparseArrayCompat<String>().apply {
-            for (field in WifiManager::class.java.declaredFields) try {
-                // all SAP_START_FAILURE_* are system-api since API 30
-                if (field.name.startsWith("SAP_START_FAILURE_")) put(field.get(null) as Int, field.name)
-            } catch (e: Exception) {
-                Timber.w(e)
-            }
-        }
-    }
-    fun failureReason(reason: Int): String {
-        if (Build.VERSION.SDK_INT >= 30) try {
-            startFailures.get(reason)?.let { return it }
-        } catch (e: ReflectiveOperationException) {
-            Timber.w(e)
-        }
-        return startFailures29.getOrNull(reason) ?: app.getString(R.string.failure_reason_unknown, reason)
-    }
 
     private val interfaceSoftApCallback by lazy { Class.forName("android.net.wifi.WifiManager\$SoftApCallback") }
     private val registerSoftApCallback by lazy {

mobile/src/main/java/be/mygod/vpnhotspot/util/ConstantLookup.kt

@@ -0,0 +1,33 @@
+package be.mygod.vpnhotspot.util
+
+import android.os.Build
+import androidx.collection.SparseArrayCompat
+import be.mygod.vpnhotspot.App.Companion.app
+import be.mygod.vpnhotspot.R
+import timber.log.Timber
+
+class ConstantLookup(private val clazz: Class<*>, private val prefix: String, private val lookup29: Array<out String>) {
+    private val lookup by lazy {
+        SparseArrayCompat<String>().apply {
+            for (field in clazz.declaredFields) try {
+                if (field.name.startsWith(prefix)) put(field.get(null) as Int, field.name)
+            } catch (e: Exception) {
+                Timber.w(e)
+            }
+        }
+    }
+    operator fun invoke(reason: Int): String {
+        if (Build.VERSION.SDK_INT >= 30) try {
+            lookup.get(reason)?.let { return it }
+        } catch (e: ReflectiveOperationException) {
+            Timber.w(e)
+        }
+        return lookup29.getOrNull(reason) ?: app.getString(R.string.failure_reason_unknown, reason)
+    }
+}
+
+@Suppress("FunctionName")
+fun ConstantLookup(clazz: Class<*>, prefix: String, vararg lookup29: String) = ConstantLookup(clazz, prefix, lookup29)
+@Suppress("FunctionName")
+inline fun <reified T> ConstantLookup(prefix: String, vararg lookup29: String) =
+        ConstantLookup(T::class.java, prefix, lookup29)