Add encryption option to PPTP UI.

Also add new error dialogs for L2TP challenge error and remote server
hanging up error.
diff --git a/res/values/strings.xml b/res/values/strings.xml
index 108bd5f..5d89800 100644
--- a/res/values/strings.xml
+++ b/res/values/strings.xml
@@ -1848,8 +1848,10 @@
     <string name="vpn_confirm_edit_profile_cancellation">Are you sure you want to discard the changes made to this profile?</string>
     <string name="vpn_confirm_reconnect">Unable to connect to the network. Do you want to try again?</string>
     <string name="vpn_unknown_server_dialog_msg">Server name cannot be resolved. Do you want to check your server name setting?</string>
+    <string name="vpn_challenge_error_dialog_msg">Challenge error. Do you want to check your secret setting?</string>
     <string name="vpn_secret_not_set_dialog_msg">One or more secrets are missing in this VPN configuration. Do you want to check your secret setting?</string>
     <string name="vpn_auth_error_dialog_msg">The username or password you entered is incorrect. Do you want to try again?</string>
+    <string name="vpn_remote_hung_up_error_dialog_msg">Server hung up. The username or password you entered could be incorrect. Do you want to try again?</string>
 
     <!-- VPN type selection activity title -->
     <string name="vpn_type_title">Add VPN</string>
@@ -1895,6 +1897,8 @@
     <!-- Complete term -->
     <string name="vpn_l2tp_secret">L2TP secret</string>
     <string name="vpn_a_l2tp_secret">an L2TP secret</string>
+    <string name="vpn_pptp_encryption_title">encryption</string>
+    <string name="vpn_pptp_encryption">PPTP encryption</string>
 
     <!-- Preference title -->
     <string name="vpn_ipsec_presharedkey_title">Set IPSec pre-shared key</string>
diff --git a/src/com/android/settings/vpn/PptpEditor.java b/src/com/android/settings/vpn/PptpEditor.java
new file mode 100644
index 0000000..fafe6a7
--- /dev/null
+++ b/src/com/android/settings/vpn/PptpEditor.java
@@ -0,0 +1,75 @@
+/* * Copyright (C) 2009 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.settings.vpn;
+
+import com.android.settings.R;
+
+import android.content.Context;
+import android.net.vpn.PptpProfile;
+import android.preference.CheckBoxPreference;
+import android.preference.Preference;
+import android.preference.PreferenceGroup;
+
+/**
+ * The class for editing {@link PptpProfile}.
+ */
+class PptpEditor extends VpnProfileEditor {
+    private CheckBoxPreference mEncryption;
+
+    public PptpEditor(PptpProfile p) {
+        super(p);
+    }
+
+    @Override
+    protected void loadExtraPreferencesTo(PreferenceGroup subpanel) {
+        Context c = subpanel.getContext();
+        subpanel.addPreference(createEncryptionPreference(c));
+
+        PptpProfile profile = (PptpProfile) getProfile();
+    }
+
+    private Preference createEncryptionPreference(Context c) {
+        final PptpProfile profile = (PptpProfile) getProfile();
+        CheckBoxPreference encryption = mEncryption = new CheckBoxPreference(c);
+        boolean enabled = profile.isEncryptionEnabled();
+        setSecretTitle(encryption, R.string.vpn_pptp_encryption_title, enabled);
+        encryption.setChecked(enabled);
+        setEncryptionSummary(encryption, enabled);
+        encryption.setOnPreferenceChangeListener(
+                new Preference.OnPreferenceChangeListener() {
+                    public boolean onPreferenceChange(
+                            Preference pref, Object newValue) {
+                        boolean enabled = (Boolean) newValue;
+                        profile.setEncryptionEnabled(enabled);
+                        setSecretTitle(mEncryption,
+                                R.string.vpn_pptp_encryption_title, enabled);
+                        setEncryptionSummary(mEncryption, enabled);
+                        return true;
+                    }
+                });
+        return encryption;
+    }
+
+    private void setEncryptionSummary(CheckBoxPreference encryption,
+            boolean enabled) {
+        Context c = encryption.getContext();
+        String formatString = c.getString(enabled
+                ? R.string.vpn_is_enabled
+                : R.string.vpn_is_disabled);
+        encryption.setSummary(String.format(
+                formatString, c.getString(R.string.vpn_pptp_encryption)));
+    }
+}
diff --git a/src/com/android/settings/vpn/VpnEditor.java b/src/com/android/settings/vpn/VpnEditor.java
index 162c129..497f4bf 100644
--- a/src/com/android/settings/vpn/VpnEditor.java
+++ b/src/com/android/settings/vpn/VpnEditor.java
@@ -24,6 +24,7 @@
 import android.net.vpn.L2tpIpsecProfile;
 import android.net.vpn.L2tpIpsecPskProfile;
 import android.net.vpn.L2tpProfile;
+import android.net.vpn.PptpProfile;
 import android.net.vpn.VpnProfile;
 import android.net.vpn.VpnType;
 import android.os.Bundle;
@@ -162,6 +163,9 @@
             case L2TP:
                 return new L2tpEditor((L2tpProfile) p);
 
+            case PPTP:
+                return new PptpEditor((PptpProfile) p);
+
             default:
                 return new VpnProfileEditor(p);
         }
diff --git a/src/com/android/settings/vpn/VpnSettings.java b/src/com/android/settings/vpn/VpnSettings.java
index 0dc1719..4dda152 100644
--- a/src/com/android/settings/vpn/VpnSettings.java
+++ b/src/com/android/settings/vpn/VpnSettings.java
@@ -109,6 +109,8 @@
     private static final int DIALOG_AUTH_ERROR = 3;
     private static final int DIALOG_UNKNOWN_SERVER = 4;
     private static final int DIALOG_SECRET_NOT_SET = 5;
+    private static final int DIALOG_CHALLENGE_ERROR = 6;
+    private static final int DIALOG_REMOTE_HUNG_UP_ERROR = 7;
 
     private static final int NO_ERROR = 0;
 
@@ -204,6 +206,12 @@
             case DIALOG_AUTH_ERROR:
                 return createAuthErrorDialog();
 
+            case DIALOG_REMOTE_HUNG_UP_ERROR:
+                return createRemoteHungUpErrorDialog();
+
+            case DIALOG_CHALLENGE_ERROR:
+                return createChallengeErrorDialog();
+
             case DIALOG_UNKNOWN_SERVER:
                 return createUnknownServerDialog();
 
@@ -244,17 +252,22 @@
                 .setMessage(R.string.vpn_auth_error_dialog_msg)
                 .create();
     }
-    private Dialog createUnknownServerDialog() {
+
+    private Dialog createRemoteHungUpErrorDialog() {
         return createCommonDialogBuilder()
+                .setMessage(R.string.vpn_remote_hung_up_error_dialog_msg)
+                .create();
+    }
+
+    private Dialog createChallengeErrorDialog() {
+        return createCommonEditDialogBuilder()
+                .setMessage(R.string.vpn_challenge_error_dialog_msg)
+                .create();
+    }
+
+    private Dialog createUnknownServerDialog() {
+        return createCommonEditDialogBuilder()
                 .setMessage(R.string.vpn_unknown_server_dialog_msg)
-                .setPositiveButton(R.string.vpn_yes_button,
-                        new DialogInterface.OnClickListener() {
-                            public void onClick(DialogInterface dialog, int w) {
-                                VpnProfile p = mConnectingActor.getProfile();
-                                onIdle();
-                                startVpnEditor(p);
-                            }
-                        })
                 .create();
     }
 
@@ -271,6 +284,18 @@
                 .create();
     }
 
+    private AlertDialog.Builder createCommonEditDialogBuilder() {
+        return createCommonDialogBuilder()
+                .setPositiveButton(R.string.vpn_yes_button,
+                        new DialogInterface.OnClickListener() {
+                            public void onClick(DialogInterface dialog, int w) {
+                                VpnProfile p = mConnectingActor.getProfile();
+                                onIdle();
+                                startVpnEditor(p);
+                            }
+                        });
+    }
+
     private AlertDialog.Builder createCommonDialogBuilder() {
         return new AlertDialog.Builder(this)
                 .setTitle(android.R.string.dialog_alert_title)
@@ -723,6 +748,14 @@
                     showDialog(DIALOG_AUTH_ERROR);
                     break;
 
+                case VpnManager.VPN_ERROR_REMOTE_HUNG_UP:
+                    showDialog(DIALOG_REMOTE_HUNG_UP_ERROR);
+                    break;
+
+                case VpnManager.VPN_ERROR_CHALLENGE:
+                    showDialog(DIALOG_CHALLENGE_ERROR);
+                    break;
+
                 case VpnManager.VPN_ERROR_UNKNOWN_SERVER:
                     showDialog(DIALOG_UNKNOWN_SERVER);
                     break;