Style quoted text with a bar on the left

Update wikify() to understand the quoted text format now used on
ChangeScreen2 when replying to a comment. Hide the " > " prefix
markers and instead display a horizontal bar down the left margin.
This style of presentation is commonly used in modern email clients
for quoted text.

Change-Id: Ib7cb309a17dedfb00af7fb82c776b07055f8d47d

gerrit-gwtexpui/src/main/java/com/google/gwtexpui/safehtml/client/SafeHtml.java

@@ -52,6 +52,10 @@ public abstract class SafeHtml
               return "wikiPreFormat";
             }
 
+            public String wikiQuote() {
+              return "wikiQuote";
+            }
+
             public boolean ensureInjected() {
               return false;
             }
@@ -139,7 +143,10 @@ public abstract class SafeHtml
   public SafeHtml wikify() {
     final SafeHtmlBuilder r = new SafeHtmlBuilder();
     for (final String p : linkify().asString().split("\n\n")) {
-      if (isPreFormat(p)) {
+      if (isQuote(p)) {
+        wikifyQuote(r, p);
+
+      } else if (isPreFormat(p)) {
         r.openElement("p");
         for (final String line : p.split("\n")) {
           r.openSpan();
@@ -202,6 +209,31 @@ public abstract class SafeHtml
     }
   }
 
+  private void wikifyQuote(SafeHtmlBuilder r, String p) {
+    r.openElement("blockquote");
+    r.setStyleName(RESOURCES.css().wikiQuote());
+    if (p.startsWith("> ")) {
+      p = p.substring(5);
+    } else if (p.startsWith(" > ")) {
+      p = p.substring(6);
+    }
+    p = p.replaceAll("\\n ?> ", "\n");
+    for (String e : p.split("\n\n")) {
+      if (isQuote(e)) {
+        SafeHtmlBuilder b = new SafeHtmlBuilder();
+        wikifyQuote(b, e);
+        r.append(b);
+      } else {
+        r.append(asis(e));
+      }
+    }
+    r.closeElement("blockquote");
+  }
+
+  private static boolean isQuote(String p) {
+    return p.startsWith("> ") || p.startsWith(" > ");
+  }
+
   private static boolean isPreFormat(final String p) {
     return p.contains("\n ") || p.contains("\n\t") || p.startsWith(" ")
         || p.startsWith("\t");

gerrit-gwtexpui/src/main/java/com/google/gwtexpui/safehtml/client/SafeHtmlCss.java

@@ -17,6 +17,7 @@ package com.google.gwtexpui.safehtml.client;
 import com.google.gwt.resources.client.CssResource;
 
 public interface SafeHtmlCss extends CssResource {
-  String wikiPreFormat();
   String wikiList();
+  String wikiPreFormat();
+  String wikiQuote();
 }

gerrit-gwtexpui/src/main/java/com/google/gwtexpui/safehtml/client/safehtml.css

@@ -13,11 +13,17 @@
  * limitations under the License.
  */
 
+.wikiList {
+}
+
 .wikiPreFormat {
   white-space: pre;
   font-family: 'Lucida Console', 'Lucida Sans Typewriter', Monaco, monospace;
   font-size: small;
 }
 
-.wikiList {
+.wikiQuote {
+  margin-left: 0;
+  border-left: 1px solid #888;
+  padding-left: 5px;
 }

gerrit-gwtui/src/main/java/com/google/gerrit/client/change/Message.ui.xml

@@ -48,7 +48,8 @@ limitations under the License.
       position: relative;
     }
 
-    .contents p {
+    .contents p,
+    .contents blockquote {
       -webkit-margin-before: 0;
       -webkit-margin-after: 0.3em;
     }

gerrit-gwtui/src/main/java/com/google/gerrit/client/diff/CommentBoxUi.css

@@ -54,7 +54,8 @@
   position: relative;
 }
 .contents p,
-.contents ul {
+.contents ul,
+.contents blockquote {
   -webkit-margin-before: 0;
   -webkit-margin-after: 0.3em;
 }