Simplified decryption of inline encrypted messages

FAQ.md

@@ -517,9 +517,10 @@ So, unless your provider can enable this extension, you cannot use FairEmail for
 **(12) How does encryption/decryption work?**
 
 First of all you need to install and configure [OpenKeychain](https://f-droid.org/en/packages/org.sufficientlysecure.keychain/).
+
 To encrypt and send a message just check the menu *Encrypt* and the message will be encrypted on sending.
-To decrypt a received message, open the message and tap the padlock icon just below the grey message action bar.
+
-If the message is inline encrypted (not advised), select the menu *Decrypt* in the message 'more' three dots menu.
+To decrypt a received message, open the message and just tap the padlock icon just below the grey message action bar.
 
 The first time you send an encrypted message you might be asked for a sign key.
 FairEmail will automatically store the sign key ID in the selected identity for the next time.

app/src/main/java/eu/faircode/email/AdapterMessage.java

@@ -1210,6 +1210,7 @@ public class AdapterMessage extends RecyclerView.Adapter<AdapterMessage.ViewHold
                 attachments = new ArrayList<>();
             properties.setAttachments(message.id, attachments);
 
+            boolean iencrypted = properties.getValue("iencrypted", message.id);
             boolean show_inline = properties.getValue("inline", message.id);
             Log.i("Show inline=" + show_inline);
 
@@ -1260,7 +1261,7 @@ public class AdapterMessage extends RecyclerView.Adapter<AdapterMessage.ViewHold
             btnDownloadAttachments.setVisibility(download && suitable ? View.VISIBLE : View.GONE);
             tvNoInternetAttachments.setVisibility(downloading && !suitable ? View.VISIBLE : View.GONE);
 
-            ibDecrypt.setVisibility(is_encrypted ? View.VISIBLE : View.GONE);
+            ibDecrypt.setVisibility(iencrypted || is_encrypted ? View.VISIBLE : View.GONE);
 
             cbInline.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
                 @Override
@@ -2432,9 +2433,6 @@ public class AdapterMessage extends RecyclerView.Adapter<AdapterMessage.ViewHold
 
             popupMenu.getMenu().findItem(R.id.menu_manage_keywords).setEnabled(message.uid != null && !message.folderReadOnly);
 
-            popupMenu.getMenu().findItem(R.id.menu_decrypt).setEnabled(
-                    message.content && message.to != null && message.to.length > 0);
-
             popupMenu.getMenu().findItem(R.id.menu_resync).setEnabled(message.uid != null);
 
             popupMenu.getMenu().findItem(R.id.menu_create_rule).setEnabled(!message.accountPop);
@@ -2461,9 +2459,6 @@ public class AdapterMessage extends RecyclerView.Adapter<AdapterMessage.ViewHold
                         case R.id.menu_junk:
                             onMenuJunk(message);
                             return true;
-                        case R.id.menu_decrypt:
-                            onActionDecrypt(message);
-                            return true;
                         case R.id.menu_resync:
                             onMenuResync(message);
                             return true;
@@ -2545,6 +2540,12 @@ public class AdapterMessage extends RecyclerView.Adapter<AdapterMessage.ViewHold
                 String body = Helper.readText(file);
                 Document document = Jsoup.parse(body);
 
+                // Check for inline encryption
+                int begin = body.indexOf(Helper.PGP_BEGIN_MESSAGE);
+                int end = body.indexOf(Helper.PGP_END_MESSAGE);
+                args.putBoolean("iencrypted", begin >= 0 && begin < end);
+
+                // Check for images
                 boolean has_images = false;
                 for (Element img : document.select("img")) {
                     if (inline) {
@@ -2560,12 +2561,14 @@ public class AdapterMessage extends RecyclerView.Adapter<AdapterMessage.ViewHold
                 }
                 args.putBoolean("has_images", has_images);
 
+                // Collapse quotes
                 if (!show_quotes) {
                     for (Element quote : document.select("blockquote"))
                         quote.html("&#8230;");
                     body = document.html();
                 }
 
+                // Cleanup message
                 String html = HtmlHelper.sanitize(context, body, text_color, show_images);
                 if (debug) {
                     Document format = Jsoup.parse(html);
@@ -2590,6 +2593,7 @@ public class AdapterMessage extends RecyclerView.Adapter<AdapterMessage.ViewHold
                     }
                 }, null);
 
+                // Replace quote spans
                 SpannableStringBuilder builder = new SpannableStringBuilder(spanned);
                 QuoteSpan[] quoteSpans = builder.getSpans(0, builder.length(), QuoteSpan.class);
                 for (QuoteSpan quoteSpan : quoteSpans) {
@@ -2601,6 +2605,7 @@ public class AdapterMessage extends RecyclerView.Adapter<AdapterMessage.ViewHold
                     builder.removeSpan(quoteSpan);
                 }
 
+                // Make collapsed quotes clickable
                 if (!show_quotes) {
                     final int px = Helper.dp2pixels(context, 24 + (zoom) * 8);
 
@@ -2627,6 +2632,7 @@ public class AdapterMessage extends RecyclerView.Adapter<AdapterMessage.ViewHold
             protected void onExecuted(Bundle args, SpannableStringBuilder body) {
                 TupleMessageEx message = (TupleMessageEx) args.getSerializable("message");
                 properties.setBody(message.id, body);
+                properties.setValue("iencrypted", message.id, args.getBoolean("iencrypted"));
 
                 TupleMessageEx amessage = getMessage();
                 if (amessage == null || !amessage.id.equals(message.id))

app/src/main/java/eu/faircode/email/FragmentMessages.java

@@ -266,10 +266,6 @@ public class FragmentMessages extends FragmentBase implements SharedPreferences.
     static final String ACTION_STORE_RAW = BuildConfig.APPLICATION_ID + ".STORE_RAW";
     static final String ACTION_DECRYPT = BuildConfig.APPLICATION_ID + ".DECRYPT";
 
-    private static final String PGP_BEGIN_MESSAGE = "-----BEGIN PGP MESSAGE-----";
-    private static final String PGP_END_MESSAGE = "-----END PGP MESSAGE-----";
-
-
     private static final List<String> DUPLICATE_ORDER = Collections.unmodifiableList(Arrays.asList(
             EntityFolder.INBOX,
             EntityFolder.OUTBOX,
@@ -3803,10 +3799,10 @@ public class FragmentMessages extends FragmentBase implements SharedPreferences.
                         if (file.exists()) {
                             // https://tools.ietf.org/html/rfc4880#section-6.2
                             String body = Helper.readText(file);
-                            int begin = body.indexOf(PGP_BEGIN_MESSAGE);
+                            int begin = body.indexOf(Helper.PGP_BEGIN_MESSAGE);
-                            int end = body.indexOf(PGP_END_MESSAGE);
+                            int end = body.indexOf(Helper.PGP_END_MESSAGE);
                             if (begin >= 0 && begin < end) {
-                                String section = body.substring(begin, end + PGP_END_MESSAGE.length());
+                                String section = body.substring(begin, end + Helper.PGP_END_MESSAGE.length());
                                 String[] lines = section.split("<br>");
                                 List<String> disarmored = new ArrayList<>();
                                 for (String line : lines)

app/src/main/java/eu/faircode/email/Helper.java

@@ -114,6 +114,9 @@ public class Helper {
 
     static final int BUFFER_SIZE = 8192; // Same as in Files class
 
+    static final String PGP_BEGIN_MESSAGE = "-----BEGIN PGP MESSAGE-----";
+    static final String PGP_END_MESSAGE = "-----END PGP MESSAGE-----";
+
     static final String FAQ_URI = "https://github.com/M66B/FairEmail/blob/master/FAQ.md";
     static final String XDA_URI = "https://forum.xda-developers.com/showthread.php?t=3824168";
     static final String SUPPORT_URI = "https://contact.faircode.eu/?product=fairemailsupport";

app/src/main/res/menu/popup_message_more.xml

@@ -24,10 +24,6 @@
         android:id="@+id/menu_junk"
         android:title="@string/title_spam" />
 
-    <item
-        android:id="@+id/menu_decrypt"
-        android:title="@string/title_decrypt" />
-
     <item
         android:id="@+id/menu_resync"
         android:title="@string/title_resync" />