Support install link

Closes #2001
Fixes #1722

res/menu/conversation_insecure.xml

@@ -1,13 +1,7 @@
 <?xml version="1.0" encoding="utf-8"?>
-<menu xmlns:android="http://schemas.android.com/apk/res/android" xmlns:app="http://schemas.android.com/apk/res-auto">
-    <item android:title="Security"
-          android:id="@+id/menu_security"
-          android:icon="?menu_unlock_icon"
-          app:showAsAction="ifRoom">
-          <menu>
-              <item android:title="@string/conversation_insecure__menu_start_secure_session"
-                    android:id="@+id/menu_start_secure_session" />
+<menu xmlns:android="http://schemas.android.com/apk/res/android">
+
+    <item android:title="Invite"
+          android:id="@+id/menu_invite"/>
 
-          </menu>
-    </item>
 </menu>

res/menu/conversation_insecure_no_push.xml

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="utf-8"?>
+<menu xmlns:android="http://schemas.android.com/apk/res/android" xmlns:app="http://schemas.android.com/apk/res-auto">
+    <item android:title="Security"
+          android:id="@+id/menu_security"
+          android:icon="?menu_unlock_icon"
+          app:showAsAction="ifRoom">
+          <menu>
+              <item android:title="@string/conversation_insecure__menu_start_secure_session"
+                    android:id="@+id/menu_start_secure_session" />
+
+          </menu>
+    </item>
+</menu>

res/values/strings.xml

@@ -109,6 +109,8 @@
     <string name="ConversationActivity_transport_secure_sms">Secure SMS</string>
     <string name="ConversationActivity_transport_secure_mms">Secure MMS</string>
     <string name="ConversationActivity_transport_textsecure">TextSecure</string>
+    <string name="ConversationActivity_get_with_it">Get with it: %s</string>
+    <string name="ConversationActivity_install_textsecure">Install TextSecure: %s</string>
 
     <!-- ConversationFragment -->
     <string name="ConversationFragment_message_details">Message details</string>
@@ -750,7 +752,7 @@
     <!-- conversation_context_image -->
     <string name="conversation_context_image__save_attachment">Save attachment</string>
 
-    <!-- conversation_insecure -->
+    <!-- conversation_insecure_no_push -->
     <string name="conversation_insecure__menu_start_secure_session">Start secure session</string>
 
     <!-- conversation_list_batch -->

src/org/thoughtcrime/securesms/ConversationActivity.java

@@ -41,7 +41,6 @@ import android.view.KeyEvent;
 import android.view.Menu;
 import android.view.MenuInflater;
 import android.view.MenuItem;
-import android.view.LayoutInflater;
 import android.view.View;
 import android.view.View.OnClickListener;
 import android.view.View.OnFocusChangeListener;
@@ -109,7 +108,8 @@ import org.whispersystems.libaxolotl.state.SessionStore;
 import org.whispersystems.textsecure.api.push.PushAddress;
 
 import java.io.IOException;
-import java.util.LinkedList;
+import java.security.NoSuchAlgorithmException;
+import java.security.SecureRandom;
 import java.util.List;
 
 import static org.thoughtcrime.securesms.database.GroupDatabase.GroupRecord;
@@ -257,7 +257,8 @@ public class ConversationActivity extends PassphraseRequiredActionBarActivity
     if (isSingleConversation() && isEncryptedConversation) {
       inflater.inflate(R.menu.conversation_secure_identity, menu);
       inflater.inflate(R.menu.conversation_secure_sms, menu.findItem(R.id.menu_security).getSubMenu());
-    } else if (isSingleConversation() && !pushRegistered) {
+    } else if (isSingleConversation()) {
+      if (!pushRegistered) inflater.inflate(R.menu.conversation_insecure_no_push, menu);
       inflater.inflate(R.menu.conversation_insecure, menu);
     }
 
@@ -304,6 +305,7 @@ public class ConversationActivity extends PassphraseRequiredActionBarActivity
     case R.id.menu_distribution_conversation: handleDistributionConversationEnabled(item);       return true;
     case R.id.menu_edit_group:                handleEditPushGroup();                             return true;
     case R.id.menu_leave:                     handleLeavePushGroup();                            return true;
+    case R.id.menu_invite:                    handleInviteLink();                                return true;
     case android.R.id.home:                   handleReturnToConversationList();                  return true;
     }
 
@@ -330,6 +332,16 @@ public class ConversationActivity extends PassphraseRequiredActionBarActivity
     finish();
   }
 
+  private void handleInviteLink() {
+    try {
+      boolean a = SecureRandom.getInstance("SHA1PRNG").nextBoolean();
+      if (a) composeText.setText(getString(R.string.ConversationActivity_get_with_it, "http://sgnl.link/zhrzvk6"));
+      else   composeText.setText(getString(R.string.ConversationActivity_install_textsecure, "http://sgnl.link/1yKYqoN"));
+    } catch (NoSuchAlgorithmException e) {
+      throw new AssertionError(e);
+    }
+  }
+
   private void handleVerifyIdentity() {
     Intent verifyIdentityIntent = new Intent(this, VerifyIdentityActivity.class);
     verifyIdentityIntent.putExtra("recipient", getRecipients().getPrimaryRecipient());
@@ -846,10 +858,11 @@ public class ConversationActivity extends PassphraseRequiredActionBarActivity
   }
 
   private void selectContactInfo(ContactData contactData) {
-    final CharSequence[] numbers = new CharSequence[contactData.numbers.size()];
+    final CharSequence[] numbers     = new CharSequence[contactData.numbers.size()];
     final CharSequence[] numberItems = new CharSequence[contactData.numbers.size()];
+
     for (int i = 0; i < contactData.numbers.size(); i++) {
-      numbers[i] = contactData.numbers.get(i).number;
+      numbers[i]     = contactData.numbers.get(i).number;
       numberItems[i] = contactData.numbers.get(i).type + ": " + contactData.numbers.get(i).number;
     }