Quote in right direction

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

@@ -649,7 +649,7 @@ public class EntityRule {
         Element e = answering.body();
         if (quote) {
             String style = e.attr("style");
-            style = HtmlHelper.mergeStyles(style, HtmlHelper.QUOTE_STYLE);
+            style = HtmlHelper.mergeStyles(style, HtmlHelper.getQuoteStyle(e));
             e.tagName("blockquote").attr("style", style);
         } else
             e.tagName("p");

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

@@ -4362,7 +4362,7 @@ public class FragmentCompose extends FragmentBase {
 
                             if (quote) {
                                 String style = e.attr("style");
-                                style = HtmlHelper.mergeStyles(style, HtmlHelper.QUOTE_STYLE);
+                                style = HtmlHelper.mergeStyles(style, HtmlHelper.getQuoteStyle(e));
                                 e.tagName("blockquote").attr("style", style);
                             } else
                                 e.tagName("p");

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

@@ -144,7 +144,8 @@ public class HtmlEx {
 
             for (Object quote : quotes) {
                 if (quote instanceof QuoteSpan)
-                    out.append("<blockquote style=\"" + eu.faircode.email.HtmlHelper.QUOTE_STYLE +"\">");
+                    out.append("<blockquote style=\"" +
+                            eu.faircode.email.HtmlHelper.getQuoteStyle(text, next, end) + "\">");
                 else
                     out.append("<blockquote>");
             }

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

@@ -126,7 +126,6 @@ public class HtmlHelper {
 
     static final float FONT_SMALL = 0.8f;
     static final float FONT_LARGE = 1.25f;
-    static final String QUOTE_STYLE = "border-left:3px solid #ccc; padding-left:3px;";
 
     private static final int DEFAULT_FONT_SIZE = 16; // pixels
     private static final int DEFAULT_FONT_SIZE_PT = 12; // points
@@ -2013,6 +2012,22 @@ public class HtmlHelper {
         return d.text();
     }
 
+    static String getQuoteStyle(Element e) {
+        CharSequence text = e.text();
+        return getQuoteStyle(text, 0, text.length());
+    }
+
+    static String getQuoteStyle(CharSequence quoted, int start, int end) {
+        try {
+            if (TextDirectionHeuristics.FIRSTSTRONG_LTR.isRtl(quoted, start, end))
+                return "border-right:3px solid #ccc; padding-left:3px;";
+        } catch (Throwable ex) {
+            Log.e(ex);
+        }
+
+        return "border-left:3px solid #ccc; padding-left:3px;";
+    }
+
     static boolean hasBorder(Element e) {
         return "true".equals(e.attr("x-border"));
     }