Convert ErrorMessages to Kotlin

Signed-off-by: Harsh Shandilya <me@msfjarvis.dev>

2 files changed, 138 insertions, 160 deletions

diff --git a/ui/src/main/java/com/wireguard/android/util/ErrorMessages.java b/ui/src/main/java/com/wireguard/android/util/ErrorMessages.java
deleted file mode 100644
index 98eac3e6..00000000
--- a/ui/src/main/java/com/wireguard/android/util/ErrorMessages.java
+++ /dev/null
@@ -1,160 +0,0 @@
-/*
- * Copyright © 2018-2019 WireGuard LLC. All Rights Reserved.
- * SPDX-License-Identifier: Apache-2.0
- */
-
-package com.wireguard.android.util;
-
-import android.content.res.Resources;
-import android.os.RemoteException;
-
-import com.wireguard.android.Application;
-import com.wireguard.android.R;
-import com.wireguard.android.backend.BackendException;
-import com.wireguard.android.util.RootShell.RootShellException;
-import com.wireguard.config.BadConfigException;
-import com.wireguard.config.BadConfigException.Location;
-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 com.wireguard.util.NonNullForAll;
-
-import java.net.InetAddress;
-import java.util.EnumMap;
-import java.util.Map;
-
-import androidx.annotation.Nullable;
-import java9.util.Maps;
-
-@NonNullForAll
-public final class ErrorMessages {
-    private static final Map<BadConfigException.Reason, Integer> BCE_REASON_MAP = new EnumMap<>(Maps.of(
-            BadConfigException.Reason.INVALID_KEY, R.string.bad_config_reason_invalid_key,
-            BadConfigException.Reason.INVALID_NUMBER, R.string.bad_config_reason_invalid_number,
-            BadConfigException.Reason.INVALID_VALUE, R.string.bad_config_reason_invalid_value,
-            BadConfigException.Reason.MISSING_ATTRIBUTE, R.string.bad_config_reason_missing_attribute,
-            BadConfigException.Reason.MISSING_SECTION, R.string.bad_config_reason_missing_section,
-            BadConfigException.Reason.SYNTAX_ERROR, R.string.bad_config_reason_syntax_error,
-            BadConfigException.Reason.UNKNOWN_ATTRIBUTE, R.string.bad_config_reason_unknown_attribute,
-            BadConfigException.Reason.UNKNOWN_SECTION, R.string.bad_config_reason_unknown_section
-    ));
-    private static final Map<BackendException.Reason, Integer> BE_REASON_MAP = new EnumMap<>(Maps.of(
-            BackendException.Reason.UNKNOWN_KERNEL_MODULE_NAME, R.string.module_version_error,
-            BackendException.Reason.WG_QUICK_CONFIG_ERROR_CODE, R.string.tunnel_config_error,
-            BackendException.Reason.TUNNEL_MISSING_CONFIG, R.string.no_config_error,
-            BackendException.Reason.VPN_NOT_AUTHORIZED, R.string.vpn_not_authorized_error,
-            BackendException.Reason.UNABLE_TO_START_VPN, R.string.vpn_start_error,
-            BackendException.Reason.TUN_CREATION_ERROR, R.string.tun_create_error,
-            BackendException.Reason.GO_ACTIVATION_ERROR_CODE, R.string.tunnel_on_error
-    ));
-    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 static final Map<RootShellException.Reason, Integer> RSE_REASON_MAP = new EnumMap<>(Maps.of(
-            RootShellException.Reason.NO_ROOT_ACCESS, R.string.error_root,
-            RootShellException.Reason.SHELL_MARKER_COUNT_ERROR, R.string.shell_marker_count_error,
-            RootShellException.Reason.SHELL_EXIT_STATUS_READ_ERROR, R.string.shell_exit_status_read_error,
-            RootShellException.Reason.SHELL_START_ERROR, R.string.shell_start_error,
-            RootShellException.Reason.CREATE_BIN_DIR_ERROR, R.string.create_bin_dir_error,
-            RootShellException.Reason.CREATE_TEMP_DIR_ERROR, R.string.create_temp_dir_error
-    ));
-
-    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 instanceof BackendException) {
-            final BackendException be = (BackendException) rootCause;
-            message = resources.getString(BE_REASON_MAP.get(be.getReason()), be.getFormat());
-        } else if (rootCause instanceof RootShellException) {
-            final RootShellException rse = (RootShellException) rootCause;
-            message = resources.getString(RSE_REASON_MAP.get(rse.getReason()), rse.getFormat());
-        } 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 || cause instanceof BackendException ||
-                    cause instanceof RootShellException)
-                break;
-            final Throwable nextCause = cause.getCause();
-            if (nextCause instanceof RemoteException)
-                break;
-            cause = nextCause;
-        }
-        return cause;
-    }
-}
diff --git a/ui/src/main/java/com/wireguard/android/util/ErrorMessages.kt b/ui/src/main/java/com/wireguard/android/util/ErrorMessages.kt
new file mode 100644
index 00000000..d8ac94d9
--- /dev/null
+++ b/ui/src/main/java/com/wireguard/android/util/ErrorMessages.kt
@@ -0,0 +1,138 @@
+/*
+ * Copyright © 2018-2019 WireGuard LLC. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+package com.wireguard.android.util
+
+import android.content.res.Resources
+import android.os.RemoteException
+import com.wireguard.android.Application.Companion.get
+import com.wireguard.android.R
+import com.wireguard.android.backend.BackendException
+import com.wireguard.android.util.RootShell.RootShellException
+import com.wireguard.config.BadConfigException
+import com.wireguard.config.InetEndpoint
+import com.wireguard.config.InetNetwork
+import com.wireguard.config.ParseException
+import com.wireguard.crypto.Key
+import com.wireguard.crypto.KeyFormatException
+import java.net.InetAddress
+
+object ErrorMessages {
+    private val BCE_REASON_MAP = mapOf(
+            BadConfigException.Reason.INVALID_KEY to R.string.bad_config_reason_invalid_key,
+            BadConfigException.Reason.INVALID_NUMBER to R.string.bad_config_reason_invalid_number,
+            BadConfigException.Reason.INVALID_VALUE to R.string.bad_config_reason_invalid_value,
+            BadConfigException.Reason.MISSING_ATTRIBUTE to R.string.bad_config_reason_missing_attribute,
+            BadConfigException.Reason.MISSING_SECTION to R.string.bad_config_reason_missing_section,
+            BadConfigException.Reason.SYNTAX_ERROR to R.string.bad_config_reason_syntax_error,
+            BadConfigException.Reason.UNKNOWN_ATTRIBUTE to R.string.bad_config_reason_unknown_attribute,
+            BadConfigException.Reason.UNKNOWN_SECTION to R.string.bad_config_reason_unknown_section
+    )
+    private val BE_REASON_MAP = mapOf(
+            BackendException.Reason.UNKNOWN_KERNEL_MODULE_NAME to R.string.module_version_error,
+            BackendException.Reason.WG_QUICK_CONFIG_ERROR_CODE to R.string.tunnel_config_error,
+            BackendException.Reason.TUNNEL_MISSING_CONFIG to R.string.no_config_error,
+            BackendException.Reason.VPN_NOT_AUTHORIZED to R.string.vpn_not_authorized_error,
+            BackendException.Reason.UNABLE_TO_START_VPN to R.string.vpn_start_error,
+            BackendException.Reason.TUN_CREATION_ERROR to R.string.tun_create_error,
+            BackendException.Reason.GO_ACTIVATION_ERROR_CODE to R.string.tunnel_on_error
+    )
+    private val KFE_FORMAT_MAP = mapOf(
+            Key.Format.BASE64 to R.string.key_length_explanation_base64,
+            Key.Format.BINARY to R.string.key_length_explanation_binary,
+            Key.Format.HEX to R.string.key_length_explanation_hex
+    )
+    private val KFE_TYPE_MAP = mapOf(
+            KeyFormatException.Type.CONTENTS to R.string.key_contents_error,
+            KeyFormatException.Type.LENGTH to R.string.key_length_error
+    )
+    private val PE_CLASS_MAP = mapOf(
+            InetAddress::class.java to R.string.parse_error_inet_address,
+            InetEndpoint::class.java to R.string.parse_error_inet_endpoint,
+            InetNetwork::class.java to R.string.parse_error_inet_network,
+            Int::class.java to R.string.parse_error_integer
+    )
+    private val RSE_REASON_MAP = mapOf(
+            RootShellException.Reason.NO_ROOT_ACCESS to R.string.error_root,
+            RootShellException.Reason.SHELL_MARKER_COUNT_ERROR to R.string.shell_marker_count_error,
+            RootShellException.Reason.SHELL_EXIT_STATUS_READ_ERROR to R.string.shell_exit_status_read_error,
+            RootShellException.Reason.SHELL_START_ERROR to R.string.shell_start_error,
+            RootShellException.Reason.CREATE_BIN_DIR_ERROR to R.string.create_bin_dir_error,
+            RootShellException.Reason.CREATE_TEMP_DIR_ERROR to R.string.create_temp_dir_error
+    )
+
+    operator fun get(throwable: Throwable?): String {
+        val resources = get().resources
+        if (throwable == null) return resources.getString(R.string.unknown_error)
+        val rootCause = rootCause(throwable)
+        return when {
+            rootCause is BadConfigException -> {
+                val reason = getBadConfigExceptionReason(resources, rootCause)
+                val context = if (rootCause.location == BadConfigException.Location.TOP_LEVEL) {
+                    resources.getString(R.string.bad_config_context_top_level, rootCause.section.getName())
+                } else {
+                    resources.getString(R.string.bad_config_context, rootCause.section.getName(), rootCause.location.getName())
+                }
+                val explanation = getBadConfigExceptionExplanation(resources, rootCause)
+                resources.getString(R.string.bad_config_error, reason, context) + explanation
+            }
+            rootCause is BackendException -> {
+                resources.getString(BE_REASON_MAP.getValue(rootCause.reason), *rootCause.format)
+            }
+            rootCause is RootShellException -> {
+                resources.getString(RSE_REASON_MAP.getValue(rootCause.reason), *rootCause.format)
+            }
+            rootCause.message != null -> {
+                rootCause.message!!
+            }
+            else -> {
+                val errorType = rootCause.javaClass.simpleName
+                resources.getString(R.string.generic_error, errorType)
+            }
+        }
+    }
+
+    private fun getBadConfigExceptionExplanation(resources: Resources,
+                                                 bce: BadConfigException): String {
+        if (bce.cause is KeyFormatException) {
+            val kfe = bce.cause as KeyFormatException?
+            if (kfe!!.type == KeyFormatException.Type.LENGTH) return resources.getString(KFE_FORMAT_MAP.getValue(kfe.format))
+        } else if (bce.cause is ParseException) {
+            val pe = bce.cause as ParseException?
+            if (pe!!.message != null) return ": ${pe.message}"
+        } else if (bce.location == BadConfigException.Location.LISTEN_PORT) {
+            return resources.getString(R.string.bad_config_explanation_udp_port)
+        } else if (bce.location == BadConfigException.Location.MTU) {
+            return resources.getString(R.string.bad_config_explanation_positive_number)
+        } else if (bce.location == BadConfigException.Location.PERSISTENT_KEEPALIVE) {
+            return resources.getString(R.string.bad_config_explanation_pka)
+        }
+        return ""
+    }
+
+    private fun getBadConfigExceptionReason(resources: Resources,
+                                            bce: BadConfigException): String {
+        if (bce.cause is KeyFormatException) {
+            val kfe = bce.cause as KeyFormatException?
+            return resources.getString(KFE_TYPE_MAP.getValue(kfe!!.type))
+        } else if (bce.cause is ParseException) {
+            val pe = bce.cause as ParseException?
+            val type = resources.getString((if (PE_CLASS_MAP.containsKey(pe!!.parsingClass)) PE_CLASS_MAP[pe.parsingClass] else R.string.parse_error_generic)!!)
+            return resources.getString(R.string.parse_error_reason, type, pe.text)
+        }
+        return resources.getString(BCE_REASON_MAP.getValue(bce.reason), bce.text)
+    }
+
+    private fun rootCause(throwable: Throwable): Throwable {
+        var cause = throwable
+        while (cause.cause != null) {
+            if (cause is BadConfigException || cause is BackendException ||
+                    cause is RootShellException) break
+            val nextCause = cause.cause!!
+            if (nextCause is RemoteException) break
+            cause = nextCause
+        }
+        return cause
+    }
+}