Clean up error messages

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

15 files changed, 217 insertions, 113 deletions

diff --git a/app/src/main/java/com/wireguard/android/QuickTileService.java b/app/src/main/java/com/wireguard/android/QuickTileService.java
index 2463896e..198684c1 100644
--- a/app/src/main/java/com/wireguard/android/QuickTileService.java
+++ b/app/src/main/java/com/wireguard/android/QuickTileService.java
@@ -23,7 +23,7 @@ import android.widget.Toast;
 import com.wireguard.android.activity.MainActivity;
 import com.wireguard.android.model.Tunnel;
 import com.wireguard.android.model.Tunnel.State;
-import com.wireguard.android.util.ExceptionLoggers;
+import com.wireguard.android.util.ErrorMessages;
 import com.wireguard.android.widget.SlashDrawable;
 
 import java.util.Objects;
@@ -114,7 +114,7 @@ public class QuickTileService extends TileService {
                                   @Nullable final Throwable throwable) {
         if (throwable == null)
             return;
-        final String error = ExceptionLoggers.unwrapMessage(throwable);
+        final String error = ErrorMessages.get(throwable);
         final String message = getString(R.string.toggle_error, error);
         Log.e(TAG, message, throwable);
         Toast.makeText(this, message, Toast.LENGTH_LONG).show();
diff --git a/app/src/main/java/com/wireguard/android/backend/GoBackend.java b/app/src/main/java/com/wireguard/android/backend/GoBackend.java
index b9cb573d..301bbd76 100644
--- a/app/src/main/java/com/wireguard/android/backend/GoBackend.java
+++ b/app/src/main/java/com/wireguard/android/backend/GoBackend.java
@@ -126,7 +126,7 @@ public final class GoBackend implements Backend {
             Objects.requireNonNull(config, context.getString(R.string.no_config_error));
 
             if (VpnService.prepare(context) != null)
-                throw new Exception(context.getString(R.string.vpn_not_authed_error));
+                throw new Exception(context.getString(R.string.vpn_not_authorized_error));
 
             final VpnService service;
             if (!vpnService.isDone())
diff --git a/app/src/main/java/com/wireguard/android/fragment/AppListDialogFragment.java b/app/src/main/java/com/wireguard/android/fragment/AppListDialogFragment.java
index 20633c3e..49cb51ee 100644
--- a/app/src/main/java/com/wireguard/android/fragment/AppListDialogFragment.java
+++ b/app/src/main/java/com/wireguard/android/fragment/AppListDialogFragment.java
@@ -22,7 +22,7 @@ import com.wireguard.android.Application;
 import com.wireguard.android.R;
 import com.wireguard.android.databinding.AppListDialogFragmentBinding;
 import com.wireguard.android.model.ApplicationData;
-import com.wireguard.android.util.ExceptionLoggers;
+import com.wireguard.android.util.ErrorMessages;
 import com.wireguard.android.util.ObservableKeyedArrayList;
 import com.wireguard.android.util.ObservableKeyedList;
 
@@ -73,7 +73,7 @@ public class AppListDialogFragment extends DialogFragment {
                 appData.clear();
                 appData.addAll(data);
             } else {
-                final String error = throwable != null ? ExceptionLoggers.unwrapMessage(throwable) : "Unknown";
+                final String error = ErrorMessages.get(throwable);
                 final String message = activity.getString(R.string.error_fetching_apps, error);
                 Toast.makeText(activity, message, Toast.LENGTH_LONG).show();
                 dismissAllowingStateLoss();
diff --git a/app/src/main/java/com/wireguard/android/fragment/BaseFragment.java b/app/src/main/java/com/wireguard/android/fragment/BaseFragment.java
index e3003f2e..3b2199aa 100644
--- a/app/src/main/java/com/wireguard/android/fragment/BaseFragment.java
+++ b/app/src/main/java/com/wireguard/android/fragment/BaseFragment.java
@@ -25,7 +25,7 @@ import com.wireguard.android.databinding.TunnelDetailFragmentBinding;
 import com.wireguard.android.databinding.TunnelListItemBinding;
 import com.wireguard.android.model.Tunnel;
 import com.wireguard.android.model.Tunnel.State;
-import com.wireguard.android.util.ExceptionLoggers;
+import com.wireguard.android.util.ErrorMessages;
 
 /**
  * Base class for fragments that need to know the currently-selected tunnel. Only does anything when
@@ -111,7 +111,7 @@ public abstract class BaseFragment extends Fragment implements OnSelectedTunnelC
         tunnel.setState(State.of(checked)).whenComplete((state, throwable) -> {
             if (throwable == null)
                 return;
-            final String error = ExceptionLoggers.unwrapMessage(throwable);
+            final String error = ErrorMessages.get(throwable);
             final int messageResId = checked ? R.string.error_up : R.string.error_down;
             final String message = getContext().getString(messageResId, error);
             final View view = getView();
diff --git a/app/src/main/java/com/wireguard/android/fragment/ConfigNamingDialogFragment.java b/app/src/main/java/com/wireguard/android/fragment/ConfigNamingDialogFragment.java
index 2cdf79ae..e56b4286 100644
--- a/app/src/main/java/com/wireguard/android/fragment/ConfigNamingDialogFragment.java
+++ b/app/src/main/java/com/wireguard/android/fragment/ConfigNamingDialogFragment.java
@@ -27,8 +27,8 @@ import java.nio.charset.StandardCharsets;
 import java.util.Objects;
 
 public class ConfigNamingDialogFragment extends DialogFragment {
-
     private static final String KEY_CONFIG_TEXT = "config_text";
+
     @Nullable private ConfigNamingDialogFragmentBinding binding;
     @Nullable private Config config;
     @Nullable private InputMethodManager imm;
@@ -65,23 +65,26 @@ public class ConfigNamingDialogFragment extends DialogFragment {
     public void onCreate(@Nullable final Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
 
+        final Bundle arguments = getArguments();
+        final String configText = arguments.getString(KEY_CONFIG_TEXT);
+        final byte[] configBytes = configText.getBytes(StandardCharsets.UTF_8);
         try {
-            config = Config.parse(new ByteArrayInputStream(getArguments().getString(KEY_CONFIG_TEXT).getBytes(StandardCharsets.UTF_8)));
+            config = Config.parse(new ByteArrayInputStream(configBytes));
         } catch (final BadConfigException | IOException e) {
-            throw new RuntimeException(getResources().getString(R.string.invalid_config_error, getClass().getSimpleName()), e);
+            throw new IllegalArgumentException("Invalid config passed to " + getClass().getSimpleName(), e);
         }
     }
 
     @Override
     public Dialog onCreateDialog(final Bundle savedInstanceState) {
-        final Activity activity = getActivity();
+        final Activity activity = Objects.requireNonNull(getActivity());
 
-        imm = (InputMethodManager) getActivity().getSystemService(Context.INPUT_METHOD_SERVICE);
+        imm = (InputMethodManager) activity.getSystemService(Context.INPUT_METHOD_SERVICE);
 
         final AlertDialog.Builder alertDialogBuilder = new AlertDialog.Builder(activity);
-        alertDialogBuilder.setTitle(R.string.import_from_qrcode);
+        alertDialogBuilder.setTitle(R.string.import_from_qr_code);
 
-        binding = ConfigNamingDialogFragmentBinding.inflate(getActivity().getLayoutInflater(), null, false);
+        binding = ConfigNamingDialogFragmentBinding.inflate(activity.getLayoutInflater(), null, false);
         binding.executePendingBindings();
         alertDialogBuilder.setView(binding.getRoot());
 
diff --git a/app/src/main/java/com/wireguard/android/fragment/TunnelEditorFragment.java b/app/src/main/java/com/wireguard/android/fragment/TunnelEditorFragment.java
index f1250e64..7c4a162a 100644
--- a/app/src/main/java/com/wireguard/android/fragment/TunnelEditorFragment.java
+++ b/app/src/main/java/com/wireguard/android/fragment/TunnelEditorFragment.java
@@ -28,7 +28,7 @@ import com.wireguard.android.databinding.TunnelEditorFragmentBinding;
 import com.wireguard.android.fragment.AppListDialogFragment.AppExclusionListener;
 import com.wireguard.android.model.Tunnel;
 import com.wireguard.android.model.TunnelManager;
-import com.wireguard.android.util.ExceptionLoggers;
+import com.wireguard.android.util.ErrorMessages;
 import com.wireguard.android.viewmodel.ConfigProxy;
 import com.wireguard.config.Config;
 
@@ -63,7 +63,7 @@ public class TunnelEditorFragment extends BaseFragment implements AppExclusionLi
             Toast.makeText(getContext(), message, Toast.LENGTH_SHORT).show();
             onFinished();
         } else {
-            final String error = ExceptionLoggers.unwrapMessage(throwable);
+            final String error = ErrorMessages.get(throwable);
             message = getString(R.string.config_save_error, savedTunnel.getName(), error);
             Log.e(TAG, message, throwable);
             if (binding != null) {
@@ -140,7 +140,7 @@ public class TunnelEditorFragment extends BaseFragment implements AppExclusionLi
                 try {
                     newConfig = binding.getConfig().resolve();
                 } catch (final Exception e) {
-                    final String error = ExceptionLoggers.unwrapMessage(e);
+                    final String error = ErrorMessages.get(e);
                     final String tunnelName = tunnel == null ? binding.getName() : tunnel.getName();
                     final String message = getString(R.string.config_save_error, tunnelName, error);
                     Log.e(TAG, message, e);
@@ -208,7 +208,7 @@ public class TunnelEditorFragment extends BaseFragment implements AppExclusionLi
             Toast.makeText(getContext(), message, Toast.LENGTH_SHORT).show();
             onFinished();
         } else {
-            final String error = ExceptionLoggers.unwrapMessage(throwable);
+            final String error = ErrorMessages.get(throwable);
             message = getString(R.string.tunnel_create_error, error);
             Log.e(TAG, message, throwable);
             if (binding != null) {
@@ -227,7 +227,7 @@ public class TunnelEditorFragment extends BaseFragment implements AppExclusionLi
             Log.d(TAG, "Attempting to save config of renamed tunnel " + tunnel.getName());
             renamedTunnel.setConfig(newConfig).whenComplete((a, b) -> onConfigSaved(renamedTunnel, b));
         } else {
-            final String error = ExceptionLoggers.unwrapMessage(throwable);
+            final String error = ErrorMessages.get(throwable);
             message = getString(R.string.tunnel_rename_error, error);
             Log.e(TAG, message, throwable);
             if (binding != null) {
diff --git a/app/src/main/java/com/wireguard/android/fragment/TunnelListFragment.java b/app/src/main/java/com/wireguard/android/fragment/TunnelListFragment.java
index 4a6103ba..5871f262 100644
--- a/app/src/main/java/com/wireguard/android/fragment/TunnelListFragment.java
+++ b/app/src/main/java/com/wireguard/android/fragment/TunnelListFragment.java
@@ -37,7 +37,7 @@ import com.wireguard.android.databinding.ObservableKeyedRecyclerViewAdapter;
 import com.wireguard.android.databinding.TunnelListFragmentBinding;
 import com.wireguard.android.databinding.TunnelListItemBinding;
 import com.wireguard.android.model.Tunnel;
-import com.wireguard.android.util.ExceptionLoggers;
+import com.wireguard.android.util.ErrorMessages;
 import com.wireguard.android.widget.MultiselectableRelativeLayout;
 import com.wireguard.android.widget.fab.FloatingActionsMenuRecyclerViewScrollListener;
 import com.wireguard.config.BadConfigException;
@@ -270,7 +270,7 @@ public class TunnelListFragment extends BaseFragment {
         final IntentIntegrator intentIntegrator = IntentIntegrator.forSupportFragment(this);
         intentIntegrator.setOrientationLocked(false);
         intentIntegrator.setBeepEnabled(false);
-        intentIntegrator.setPrompt(getString(R.string.qrcode_hint));
+        intentIntegrator.setPrompt(getString(R.string.qr_code_hint));
         intentIntegrator.initiateScan(Collections.singletonList(IntentIntegrator.QR_CODE));
 
         if (binding != null)
@@ -301,7 +301,7 @@ public class TunnelListFragment extends BaseFragment {
         if (throwable == null) {
             message = getResources().getQuantityString(R.plurals.delete_success, count, count);
         } else {
-            final String error = ExceptionLoggers.unwrapMessage(throwable);
+            final String error = ErrorMessages.get(throwable);
             message = getResources().getQuantityString(R.plurals.delete_error, count, count, error);
             Log.e(TAG, message, throwable);
         }
@@ -314,7 +314,7 @@ public class TunnelListFragment extends BaseFragment {
         String message = null;
 
         for (final Throwable throwable : throwables) {
-            final String error = ExceptionLoggers.unwrapMessage(throwable);
+            final String error = ErrorMessages.get(throwable);
             message = getString(R.string.import_error, error);
             Log.e(TAG, message, throwable);
         }
diff --git a/app/src/main/java/com/wireguard/android/preference/LogExporterPreference.java b/app/src/main/java/com/wireguard/android/preference/LogExporterPreference.java
index 3836f9ac..3f59c7f8 100644
--- a/app/src/main/java/com/wireguard/android/preference/LogExporterPreference.java
+++ b/app/src/main/java/com/wireguard/android/preference/LogExporterPreference.java
@@ -17,7 +17,7 @@ import android.util.Log;
 
 import com.wireguard.android.Application;
 import com.wireguard.android.R;
-import com.wireguard.android.util.ExceptionLoggers;
+import com.wireguard.android.util.ErrorMessages;
 import com.wireguard.android.util.FragmentUtils;
 
 import java.io.BufferedReader;
@@ -76,7 +76,7 @@ public class LogExporterPreference extends Preference {
 
     private void exportLogComplete(final String filePath, @Nullable final Throwable throwable) {
         if (throwable != null) {
-            final String error = ExceptionLoggers.unwrapMessage(throwable);
+            final String error = ErrorMessages.get(throwable);
             final String message = getContext().getString(R.string.log_export_error, error);
             Log.e(TAG, message, throwable);
             Snackbar.make(
@@ -98,7 +98,7 @@ public class LogExporterPreference extends Preference {
 
     @Override
     public CharSequence getTitle() {
-        return getContext().getString(R.string.log_exporter_title);
+        return getContext().getString(R.string.log_export_title);
     }
 
     @Override
diff --git a/app/src/main/java/com/wireguard/android/preference/ZipExporterPreference.java b/app/src/main/java/com/wireguard/android/preference/ZipExporterPreference.java
index f5385a2b..a2646053 100644
--- a/app/src/main/java/com/wireguard/android/preference/ZipExporterPreference.java
+++ b/app/src/main/java/com/wireguard/android/preference/ZipExporterPreference.java
@@ -18,7 +18,7 @@ import android.util.Log;
 import com.wireguard.android.Application;
 import com.wireguard.android.R;
 import com.wireguard.android.model.Tunnel;
-import com.wireguard.android.util.ExceptionLoggers;
+import com.wireguard.android.util.ErrorMessages;
 import com.wireguard.android.util.FragmentUtils;
 import com.wireguard.config.Config;
 
@@ -86,7 +86,7 @@ public class ZipExporterPreference extends Preference {
 
     private void exportZipComplete(@Nullable final String filePath, @Nullable final Throwable throwable) {
         if (throwable != null) {
-            final String error = ExceptionLoggers.unwrapMessage(throwable);
+            final String error = ErrorMessages.get(throwable);
             final String message = getContext().getString(R.string.zip_export_error, error);
             Log.e(TAG, message, throwable);
             Snackbar.make(
@@ -108,7 +108,7 @@ public class ZipExporterPreference extends Preference {
 
     @Override
     public CharSequence getTitle() {
-        return getContext().getString(R.string.zip_exporter_title);
+        return getContext().getString(R.string.zip_export_title);
     }
 
     @Override
diff --git a/app/src/main/java/com/wireguard/android/util/ErrorMessages.java b/app/src/main/java/com/wireguard/android/util/ErrorMessages.java
new file mode 100644
index 00000000..0f49448c
--- /dev/null
+++ b/app/src/main/java/com/wireguard/android/util/ErrorMessages.java
@@ -0,0 +1,130 @@
+/*
+ * Copyright © 2018 WireGuard LLC. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package com.wireguard.android.util;
+
+import android.content.res.Resources;
+import android.support.annotation.Nullable;
+
+import com.wireguard.android.Application;
+import com.wireguard.android.R;
+import com.wireguard.config.BadConfigException;
+import com.wireguard.config.BadConfigException.Location;
+import com.wireguard.config.BadConfigException.Reason;
+import com.wireguard.config.InetEndpoint;
+import com.wireguard.config.InetNetwork;
+import com.wireguard.config.ParseException;
+import com.wireguard.crypto.Key.Format;
+import com.wireguard.crypto.KeyFormatException;
+import com.wireguard.crypto.KeyFormatException.Type;
+
+import java.net.InetAddress;
+import java.util.EnumMap;
+import java.util.Map;
+
+import java9.util.Maps;
+
+public final class ErrorMessages {
+    private static final Map<Reason, Integer> BCE_REASON_MAP = new EnumMap<>(Maps.of(
+            Reason.INVALID_KEY, R.string.bad_config_reason_invalid_key,
+            Reason.INVALID_NUMBER, R.string.bad_config_reason_invalid_number,
+            Reason.INVALID_VALUE, R.string.bad_config_reason_invalid_value,
+            Reason.MISSING_ATTRIBUTE, R.string.bad_config_reason_missing_attribute,
+            Reason.MISSING_SECTION, R.string.bad_config_reason_missing_section,
+            Reason.MISSING_VALUE, R.string.bad_config_reason_missing_value,
+            Reason.SYNTAX_ERROR, R.string.bad_config_reason_syntax_error,
+            Reason.UNKNOWN_ATTRIBUTE, R.string.bad_config_reason_unknown_attribute,
+            Reason.UNKNOWN_SECTION, R.string.bad_config_reason_unknown_section
+    ));
+    private static final Map<Format, Integer> KFE_FORMAT_MAP = new EnumMap<>(Maps.of(
+            Format.BASE64, R.string.key_length_explanation_base64,
+            Format.BINARY, R.string.key_length_explanation_binary,
+            Format.HEX, R.string.key_length_explanation_hex
+    ));
+    private static final Map<Type, Integer> KFE_TYPE_MAP = new EnumMap<>(Maps.of(
+            Type.CONTENTS, R.string.key_contents_error,
+            Type.LENGTH, R.string.key_length_error
+    ));
+    private static final Map<Class, Integer> PE_CLASS_MAP = Maps.of(
+            InetAddress.class, R.string.parse_error_inet_address,
+            InetEndpoint.class, R.string.parse_error_inet_endpoint,
+            InetNetwork.class, R.string.parse_error_inet_network,
+            Integer.class, R.string.parse_error_integer
+    );
+
+    private ErrorMessages() {
+        // Prevent instantiation
+    }
+
+    public static String get(@Nullable final Throwable throwable) {
+        final Resources resources = Application.get().getResources();
+        if (throwable == null)
+            return resources.getString(R.string.unknown_error);
+        final Throwable rootCause = rootCause(throwable);
+        final String message;
+        if (rootCause instanceof BadConfigException) {
+            final BadConfigException bce = (BadConfigException) rootCause;
+            final String reason = getBadConfigExceptionReason(resources, bce);
+            final String context = bce.getLocation() == Location.TOP_LEVEL ?
+                    resources.getString(R.string.bad_config_context_top_level,
+                            bce.getSection().getName()) :
+                    resources.getString(R.string.bad_config_context,
+                            bce.getSection().getName(),
+                            bce.getLocation().getName());
+            final String explanation = getBadConfigExceptionExplanation(resources, bce);
+            message = resources.getString(R.string.bad_config_error, reason, context) + explanation;
+        } else if (rootCause.getMessage() != null) {
+            message = rootCause.getMessage();
+        } else {
+            final String errorType = rootCause.getClass().getSimpleName();
+            message = resources.getString(R.string.generic_error, errorType);
+        }
+        return message;
+    }
+
+    private static String getBadConfigExceptionExplanation(final Resources resources,
+                                                           final BadConfigException bce) {
+        if (bce.getCause() instanceof KeyFormatException) {
+            final KeyFormatException kfe = (KeyFormatException) bce.getCause();
+            if (kfe.getType() == Type.LENGTH)
+                return resources.getString(KFE_FORMAT_MAP.get(kfe.getFormat()));
+        } else if (bce.getCause() instanceof ParseException) {
+            final ParseException pe = (ParseException) bce.getCause();
+            if (pe.getMessage() != null)
+                return ": " + pe.getMessage();
+        } else if (bce.getLocation() == Location.LISTEN_PORT) {
+            return resources.getString(R.string.bad_config_explanation_udp_port);
+        } else if (bce.getLocation() == Location.MTU) {
+            return resources.getString(R.string.bad_config_explanation_positive_number);
+        } else if (bce.getLocation() == Location.PERSISTENT_KEEPALIVE) {
+            return resources.getString(R.string.bad_config_explanation_pka);
+        }
+        return "";
+    }
+
+    private static String getBadConfigExceptionReason(final Resources resources,
+                                                      final BadConfigException bce) {
+        if (bce.getCause() instanceof KeyFormatException) {
+            final KeyFormatException kfe = (KeyFormatException) bce.getCause();
+            return resources.getString(KFE_TYPE_MAP.get(kfe.getType()));
+        } else if (bce.getCause() instanceof ParseException) {
+            final ParseException pe = (ParseException) bce.getCause();
+            final String type = resources.getString(PE_CLASS_MAP.containsKey(pe.getParsingClass()) ?
+                    PE_CLASS_MAP.get(pe.getParsingClass()) : R.string.parse_error_generic);
+            return resources.getString(R.string.parse_error_reason, type, pe.getText());
+        }
+        return resources.getString(BCE_REASON_MAP.get(bce.getReason()), bce.getText());
+    }
+
+    private static Throwable rootCause(final Throwable throwable) {
+        Throwable cause = throwable;
+        while (cause.getCause() != null) {
+            if (cause instanceof BadConfigException)
+                break;
+            cause = cause.getCause();
+        }
+        return cause;
+    }
+}
diff --git a/app/src/main/java/com/wireguard/android/util/ExceptionLoggers.java b/app/src/main/java/com/wireguard/android/util/ExceptionLoggers.java
index 3cb5ca9f..5188112c 100644
--- a/app/src/main/java/com/wireguard/android/util/ExceptionLoggers.java
+++ b/app/src/main/java/com/wireguard/android/util/ExceptionLoggers.java
@@ -5,17 +5,9 @@
 
 package com.wireguard.android.util;
 
-import android.content.res.Resources;
 import android.support.annotation.Nullable;
 import android.util.Log;
 
-import com.wireguard.android.Application;
-import com.wireguard.android.R;
-import com.wireguard.config.BadConfigException;
-import com.wireguard.config.ParseException;
-import com.wireguard.crypto.KeyFormatException;
-
-import java9.util.concurrent.CompletionException;
 import java9.util.function.BiConsumer;
 
 /**
@@ -28,53 +20,12 @@ public enum ExceptionLoggers implements BiConsumer<Object, Throwable> {
     E(Log.ERROR);
 
     private static final String TAG = "WireGuard/" + ExceptionLoggers.class.getSimpleName();
-
     private final int priority;
 
     ExceptionLoggers(final int priority) {
         this.priority = priority;
     }
 
-    public static Throwable unwrap(final Throwable throwable) {
-        if (throwable instanceof CompletionException && throwable.getCause() != null)
-            return throwable.getCause();
-        if (throwable instanceof ParseException && throwable.getCause() != null)
-            return throwable.getCause();
-        return throwable;
-    }
-
-    public static String unwrapMessage(final Throwable throwable) {
-        final Throwable innerThrowable = unwrap(throwable);
-        final Resources resources = Application.get().getResources();
-        String message;
-        if (innerThrowable instanceof BadConfigException) {
-            final BadConfigException configException = (BadConfigException) innerThrowable;
-            message = resources.getString(R.string.parse_error, configException.getText(), configException.getLocation());
-            final Throwable cause = unwrap(configException);
-            if (cause.getMessage() != null)
-                message += ": " + cause.getMessage();
-        } else if (innerThrowable instanceof KeyFormatException) {
-            final KeyFormatException keyFormatException = (KeyFormatException) innerThrowable;
-            switch (keyFormatException.getFormat()) {
-                case BASE64:
-                    message = resources.getString(R.string.key_length_base64_exception_message);
-                    break;
-                case BINARY:
-                    message = resources.getString(R.string.key_length_exception_message);
-                    break;
-                case HEX:
-                    message = resources.getString(R.string.key_length_hex_exception_message);
-                    break;
-                default:
-                    // Will never happen, as getFormat is not nullable.
-                    message = null;
-            }
-        } else {
-            message = innerThrowable.getMessage();
-        }
-        return message != null ? message : innerThrowable.getClass().getSimpleName();
-    }
-
     @Override
     public void accept(final Object result, @Nullable final Throwable throwable) {
         if (throwable != null)
diff --git a/app/src/main/java/com/wireguard/android/util/RootShell.java b/app/src/main/java/com/wireguard/android/util/RootShell.java
index e48e3564..2dc02b56 100644
--- a/app/src/main/java/com/wireguard/android/util/RootShell.java
+++ b/app/src/main/java/com/wireguard/android/util/RootShell.java
@@ -123,9 +123,9 @@ public class RootShell {
                 }
             }
             if (markersSeen != 4)
-                throw new IOException(context.getString(R.string.marker_count_error, markersSeen));
+                throw new IOException(context.getString(R.string.shell_marker_count_error, markersSeen));
             if (errnoStdout != errnoStderr)
-                throw new IOException(context.getString(R.string.exit_status_read_error));
+                throw new IOException(context.getString(R.string.shell_exit_status_read_error));
             Log.v(TAG, "exit: " + errnoStdout);
             return errnoStdout;
         }
diff --git a/app/src/main/java/com/wireguard/android/widget/fab/FloatingActionsMenu.java b/app/src/main/java/com/wireguard/android/widget/fab/FloatingActionsMenu.java
index ee99c980..8b69ce35 100644
--- a/app/src/main/java/com/wireguard/android/widget/fab/FloatingActionsMenu.java
+++ b/app/src/main/java/com/wireguard/android/widget/fab/FloatingActionsMenu.java
@@ -218,7 +218,7 @@ public class FloatingActionsMenu extends ViewGroup {
         attr.recycle();
 
         if (mLabelsStyle != 0 && expandsHorizontally()) {
-            throw new IllegalStateException(getResources().getString(R.string.horizontal_expand_error));
+            throw new IllegalStateException("Action labels in horizontal expand orientation are not supported");
         }
 
         createAddButton(context);
diff --git a/app/src/main/res/layout/tunnel_list_fragment.xml b/app/src/main/res/layout/tunnel_list_fragment.xml
index d255005a..38d0dcbd 100644
--- a/app/src/main/res/layout/tunnel_list_fragment.xml
+++ b/app/src/main/res/layout/tunnel_list_fragment.xml
@@ -89,7 +89,7 @@
                 android:layout_height="wrap_content"
                 android:onClick="@{fragment::onRequestScanQRCode}"
                 app:fabSize="mini"
-                app:fab_title="@string/create_from_qrcode"
+                app:fab_title="@string/create_from_qr_code"
                 app:srcCompat="@drawable/ic_action_scan_qr_code_white" />
 
             <com.wireguard.android.widget.fab.LabeledFloatingActionButton
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index 7c9864bb..3ae499da 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -28,25 +28,41 @@
     <string name="addresses">Addresses</string>
     <string name="allowed_ips">Allowed IPs</string>
     <string name="app_name">WireGuard</string>
+    <string name="bad_config_context">%s\'s %s</string>
+    <string name="bad_config_context_top_level">%s</string>
+    <string name="bad_config_error">%s in %s</string>
+    <string name="bad_config_explanation_pka">: Must be positive and no more than 65535</string>
+    <string name="bad_config_explanation_positive_number">: Must be positive</string>
+    <string name="bad_config_explanation_udp_port">: Must be a valid UDP port number</string>
+    <string name="bad_config_reason_invalid_key">Invalid key</string>
+    <string name="bad_config_reason_invalid_number">Invalid number</string>
+    <string name="bad_config_reason_invalid_value">Invalid value</string>
+    <string name="bad_config_reason_missing_attribute">Missing attribute</string>
+    <string name="bad_config_reason_missing_section">Missing section</string>
+    <string name="bad_config_reason_missing_value">Missing value</string>
+    <string name="bad_config_reason_syntax_error">Syntax error</string>
+    <string name="bad_config_reason_unknown_attribute">Unknown attribute</string>
+    <string name="bad_config_reason_unknown_section">Unknown section</string>
+    <string name="bad_config_reason_value_out_of_range">Value out of range</string>
     <string name="bad_extension_error">File must be .conf or .zip</string>
     <string name="cancel">Cancel</string>
     <string name="config_delete_error">Cannot delete configuration file %s</string>
-    <string name="config_exists_error">Configuration for %s already exists</string>
-    <string name="config_file_exists_error">Configuration file %s already exists</string>
-    <string name="config_not_found_error">Configuration file %s not found</string>
-    <string name="config_rename_error">Cannot rename configuration file %s</string>
-    <string name="config_save_error">Unable to save configuration for “%1$s”: %2$s</string>
+    <string name="config_exists_error">Configuration for “%s” already exists</string>
+    <string name="config_file_exists_error">Configuration file “%s” already exists</string>
+    <string name="config_not_found_error">Configuration file “%s” not found</string>
+    <string name="config_rename_error">Cannot rename configuration file “%s”</string>
+    <string name="config_save_error">Cannot save configuration for “%1$s”: %2$s</string>
     <string name="config_save_success">Successfully saved configuration for “%s”</string>
     <string name="create_activity_title">Create WireGuard Tunnel</string>
-    <string name="create_bin_dir_error">Could not create local binary directory</string>
+    <string name="create_bin_dir_error">Cannot create local binary directory</string>
     <string name="create_empty">Create from scratch</string>
     <string name="create_from_file">Create from file or archive</string>
-    <string name="create_from_qrcode">Create from QR code</string>
+    <string name="create_from_qr_code">Create from QR code</string>
     <string name="create_output_dir_error">Cannot create output directory</string>
-    <string name="create_temp_dir_error">Could not create local temporary directory</string>
+    <string name="create_temp_dir_error">Cannot create local temporary directory</string>
     <string name="create_tunnel">Create Tunnel</string>
-    <string name="dark_theme_summary_off">Currently using light day theme</string>
-    <string name="dark_theme_summary_on">Currently using dark night theme</string>
+    <string name="dark_theme_summary_off">Currently using light (day) theme</string>
+    <string name="dark_theme_summary_on">Currently using dark (night) theme</string>
     <string name="dark_theme_title">Use dark theme</string>
     <string name="delete">Delete</string>
     <string name="deselect_all">Deselect All</string>
@@ -59,28 +75,25 @@
     <string name="error_up">Error bringing up tunnel: %s</string>
     <string name="exclude_private_ips">Exclude private IPs</string>
     <string name="excluded_applications">Excluded Applications</string>
-    <string name="exit_status_read_error">Unable to read exit status</string>
     <string name="generate">Generate</string>
+    <string name="generic_error">Unknown “%s” error</string>
     <string name="hint_automatic">(auto)</string>
     <string name="hint_generated">(generated)</string>
     <string name="hint_optional">(optional)</string>
     <string name="hint_random">(random)</string>
-    <string name="horizontal_expand_error">Action labels in horizontal expand orientation is not supported.</string>
-    <string name="illegal_filename_error">Illegal file name %s</string>
+    <string name="illegal_filename_error">Illegal file name “%s”</string>
     <string name="import_error">Unable to import tunnel: %s</string>
-    <string name="import_from_qrcode">Import Tunnel from QR Code</string>
+    <string name="import_from_qr_code">Import Tunnel from QR Code</string>
     <string name="import_success">Imported “%s”</string>
     <string name="interface_title">Interface</string>
-    <string name="invalid_config_error">Invalid config passed to %s</string>
-    <string name="key_length_base64_exception_message">WireGuard base64 keys must be 44 characters encoding 32 bytes</string>
-    <string name="key_length_exception_message">WireGuard keys must be 32 bytes</string>
-    <string name="key_length_hex_exception_message">WireGuard hex keys must be 64 characters encoding 32 bytes</string>
+    <string name="key_length_explanation_base64">: WireGuard base64 keys must be 44 characters (32 bytes)</string>
+    <string name="key_length_explanation_binary">: WireGuard keys must be 32 bytes</string>
+    <string name="key_length_explanation_hex">: WireGuard hex keys must be 64 characters (32 bytes)</string>
     <string name="listen_port">Listen port</string>
     <string name="log_export_error">Unable to export log: %s</string>
-    <string name="log_export_success">Saved to %s</string>
+    <string name="log_export_success">Saved to “%s”</string>
     <string name="log_export_summary">Log file will be saved to downloads folder</string>
-    <string name="log_exporter_title">Export log file</string>
-    <string name="marker_count_error">Expected 4 markers, received %i</string>
+    <string name="log_export_title">Export log file</string>
     <string name="module_version_error">Unable to determine kernel module version</string>
     <string name="mtu">MTU</string>
     <string name="multiple_tunnels_error">Only one userspace tunnel can run at a time</string>
@@ -88,7 +101,12 @@
     <string name="no_config_error">Trying to bring up a tunnel with no config</string>
     <string name="no_configs_error">No configurations found</string>
     <string name="no_tunnels_error">No tunnels exist</string>
-    <string name="parse_error">Cannot parse “%1$s” at %2$s</string>
+    <string name="parse_error_generic">string</string>
+    <string name="parse_error_inet_address">IP address</string>
+    <string name="parse_error_inet_endpoint">endpoint</string>
+    <string name="parse_error_inet_network">IP network</string>
+    <string name="parse_error_integer">number</string>
+    <string name="parse_error_reason">Cannot parse %1$s “%2$s”</string>
     <string name="peer">Peer</string>
     <string name="permission_description">Allows an app to control WireGuard tunnels. Apps with this permission may enable and disable WireGuard tunnels at will, potentially misdirecting Internet traffic.</string>
     <string name="permission_label">control WireGuard tunnels</string>
@@ -97,13 +115,15 @@
     <string name="private_key">Private key</string>
     <string name="public_key">Public key</string>
     <string name="public_key_description">Public key</string>
-    <string name="qrcode_hint">Tip: generate with `qrencode -t ansiutf8 &lt; tunnel.conf`.</string>
+    <string name="qr_code_hint">Tip: generate with `qrencode -t ansiutf8 &lt; tunnel.conf`.</string>
     <string name="restore_on_boot_summary">Bring up previously-enabled tunnels on boot</string>
     <string name="restore_on_boot_title">Restore on boot</string>
     <string name="save">Save</string>
     <string name="select_all">Select all</string>
     <string name="set_exclusions">Set Exclusions</string>
     <string name="settings">Settings</string>
+    <string name="shell_exit_status_read_error">Shell cannot read exit status</string>
+    <string name="shell_marker_count_error">Shell expected 4 markers, received %i</string>
     <string name="shell_start_error">Shell failed to start: %i</string>
     <string name="toggle_error">Error toggling WireGuard tunnel: %s</string>
     <string name="tools_installer_already">wg and wg-quick are already installed</string>
@@ -120,10 +140,7 @@
     <string name="tunnel_config_error">Unable to configure tunnel (wg-quick returned %i)</string>
     <string name="tunnel_create_error">Unable to create tunnel: %s</string>
     <string name="tunnel_create_success">Successfully created tunnel “%s”</string>
-    <string name="tunnel_error_already_exists">Tunnel %s already exists</string>
-    <string name="tunnel_error_empty_interface_address">Address is empty</string>
-    <string name="tunnel_error_empty_peer_public_key">Peer public key may not be empty</string>
-    <string name="tunnel_error_forbidden_endpoint_chars">Forbidden characters in endpoint</string>
+    <string name="tunnel_error_already_exists">Tunnel “%s” already exists</string>
     <string name="tunnel_error_invalid_name">Invalid name</string>
     <string name="tunnel_list_placeholder">Add a tunnel using the blue button</string>
     <string name="tunnel_name">Tunnel Name</string>
@@ -132,14 +149,17 @@
     <string name="tunnel_rename_success">Successfully renamed tunnel to “%s”</string>
     <string name="type_name_go_userspace">Go userspace</string>
     <string name="type_name_kernel_module">Kernel module</string>
+    <string name="unknown_error">Unknown error</string>
     <string name="version_summary">%1$s backend v%2$s</string>
     <string name="version_summary_checking">Checking %s backend version</string>
     <string name="version_summary_unknown">Unknown %s version</string>
-    <string name="version_title">WireGuard for Android v%s"</string>
-    <string name="vpn_not_authed_error">VPN service not authorized by user</string>
+    <string name="version_title">WireGuard for Android v%s</string>
+    <string name="vpn_not_authorized_error">VPN service not authorized by user</string>
     <string name="vpn_start_error">Unable to start Android VPN service</string>
     <string name="zip_export_error">Unable to export tunnels: %s</string>
-    <string name="zip_export_success">Saved to %s</string>
+    <string name="zip_export_success">Saved to “%s”</string>
     <string name="zip_export_summary">Zip file will be saved to downloads folder</string>
-    <string name="zip_exporter_title">Export tunnels to zip file</string>
+    <string name="zip_export_title">Export tunnels to zip file</string>
+    <string name="key_length_error">Incorrect key length</string>
+    <string name="key_contents_error">Bad characters in key</string>
 </resources>