Unified: Handle "showLineNumbers" preference

Make Unified respect the "showLineNumbers" preference. To make the UI
consistent with SideBySide, also show the same red bar on placeholder
gutters (those without line numbers) for diff gaps. Again for
consistency with SideBySide, show an extra pair of line numbers at the
end of the file representing the trailing newline.

Change-Id: I1eb56cb1d53e95adadc070b16f31caf16284f7a9

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

@@ -576,7 +576,15 @@ abstract class DiffScreen extends Screen {
     getChunkManager().render(diff);
   }
 
-  abstract void setShowLineNumbers(boolean b);
+  void setShowLineNumbers(boolean b) {
+    if (b) {
+      getDiffTable().addStyleName(
+          Resources.I.diffTableStyle().showLineNumbers());
+    } else {
+      getDiffTable().removeStyleName(
+          Resources.I.diffTableStyle().showLineNumbers());
+    }
+  }
 
   void setShowIntraline(boolean b) {
     if (b && getIntraLineStatus() == DiffInfo.IntraLineStatus.OFF) {
@@ -905,8 +913,8 @@ abstract class DiffScreen extends Screen {
   private GutterClickHandler onGutterClick(final CodeMirror cm) {
     return new GutterClickHandler() {
       @Override
-      public void handle(CodeMirror instance, final int line, final String gutterClass,
+      public void handle(CodeMirror instance, final int line,
-          NativeEvent clickEvent) {
+          final String gutterClass, NativeEvent clickEvent) {
         if (clickEvent.getButton() == NativeEvent.BUTTON_LEFT
             && !clickEvent.getMetaKey()
             && !clickEvent.getAltKey()
@@ -916,7 +924,8 @@ abstract class DiffScreen extends Screen {
           Scheduler.get().scheduleDeferred(new ScheduledCommand() {
             @Override
             public void execute() {
-              getCommentManager().newDraftOnGutterClick(cm, gutterClass, line + 1);
+              getCommentManager().newDraftOnGutterClick(
+                  cm, gutterClass, line + 1);
             }
           });
         }

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

@@ -35,6 +35,7 @@
   margin: 0 0 3px 0;
 }
 
-@external .dark, .noIntraline;
+@external .dark, .noIntraline, .showLineNumbers;
 .dark {}
 .noIntraline {}
+.showLineNumbers {}

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

@@ -46,6 +46,7 @@ abstract class DiffTable extends Composite {
     String range();
     String rangeHighlight();
     String diffHeader();
+    String showLineNumbers();
   }
 
   @UiField Element patchSetNavRow;

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

@@ -185,7 +185,7 @@ public class SideBySide extends DiffScreen {
     setThemeStyles(prefs.theme().isDark());
     setShowIntraline(prefs.intralineDifference());
     if (prefs.showLineNumbers()) {
-      diffTable.addStyleName(SideBySideTable.style.showLineNumbers());
+      diffTable.addStyleName(Resources.I.diffTableStyle().showLineNumbers());
     }
 
     cmA = newCm(diff.metaA(), diff.textA(), diffTable.cmA);
@@ -260,13 +260,10 @@ public class SideBySide extends DiffScreen {
 
   @Override
   void setShowLineNumbers(boolean b) {
+    super.setShowLineNumbers(b);
+
     cmA.setOption("lineNumbers", b);
     cmB.setOption("lineNumbers", b);
-    if (b) {
-      diffTable.addStyleName(SideBySideTable.style.showLineNumbers());
-    } else {
-      diffTable.removeStyleName(SideBySideTable.style.showLineNumbers());
-    }
   }
 
   @Override

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

@@ -34,7 +34,6 @@ class SideBySideTable extends DiffTable {
   interface DiffTableStyle extends CssResource {
     String intralineBg();
     String diff();
-    String showLineNumbers();
     String hideA();
     String hideB();
     String padding();

gerrit-gwtui/src/main/java/com/google/gerrit/client/diff/SideBySideTable.ui.xml

@@ -25,7 +25,7 @@ limitations under the License.
     @external .CodeMirror-dialog-bottom;
     @external .CodeMirror-cursor;
 
-    @external .dark, .noIntraline;
+    @external .dark, .noIntraline, .showLineNumbers;
 
     .difftable .patchSetNav,
     .difftable .CodeMirror {

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

@@ -41,7 +41,7 @@ import com.google.gwt.user.client.Window;
 import com.google.gwt.user.client.rpc.AsyncCallback;
 import com.google.gwt.user.client.ui.FlowPanel;
 import com.google.gwt.user.client.ui.ImageResourceRenderer;
-import com.google.gwt.user.client.ui.Label;
+import com.google.gwt.user.client.ui.InlineHTML;
 import com.google.gwtexpui.globalkey.client.GlobalKey;
 
 import net.codemirror.lib.CodeMirror;
@@ -174,7 +174,9 @@ public class Unified extends DiffScreen {
     final DiffInfo diff = getDiff();
     setThemeStyles(prefs.theme().isDark());
     setShowIntraline(prefs.intralineDifference());
-    // TODO: Handle showLineNumbers preference
+    if (prefs.showLineNumbers()) {
+      diffTable.addStyleName(Resources.I.diffTableStyle().showLineNumbers());
+    }
 
     cm = newCm(
         diff.metaA() == null ? diff.metaB() : diff.metaA(),
@@ -248,18 +250,31 @@ public class Unified extends DiffScreen {
 
   @Override
   void setShowLineNumbers(boolean b) {
-    // TODO: Implement this
+    super.setShowLineNumbers(b);
+
+    cm.refresh();
   }
 
-  LineHandle setLineNumber(DisplaySide side, final int cmLine, int line) {
+  private void setLineNumber(DisplaySide side, int cmLine, String html,
-    Label gutter = new Label(String.valueOf(line));
+      String styleName) {
+    InlineHTML gutter = new InlineHTML(html);
     diffTable.add(gutter);
-    gutter.setStyleName(UnifiedTable.style.unifiedLineNumber());
+    gutter.setStyleName(styleName);
-    return cm.setGutterMarker(cmLine,
+    cm.setGutterMarker(cmLine, side == DisplaySide.A
-        side == DisplaySide.A ? UnifiedTable.style.lineNumbersLeft()
+        ? UnifiedTable.style.lineNumbersLeft()
         : UnifiedTable.style.lineNumbersRight(), gutter.getElement());
   }
 
+  void setLineNumber(DisplaySide side, int cmLine, int line) {
+    setLineNumber(side, cmLine, String.valueOf(line),
+        UnifiedTable.style.unifiedLineNumber());
+  }
+
+  void setLineNumberEmpty(DisplaySide side, int cmLine) {
+    setLineNumber(side, cmLine, " ",
+        UnifiedTable.style.unifiedLineNumberEmpty());
+  }
+
   @Override
   void setSyntaxHighlighting(boolean b) {
     final DiffInfo diff = getDiff();

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

@@ -109,6 +109,8 @@ class UnifiedChunkManager extends ChunkManager {
         cmLine += render(current, cmLine, useIntralineBg);
       }
     }
+    host.setLineNumber(DisplaySide.A, cmLine, lineMapper.getLineA() + 1);
+    host.setLineNumber(DisplaySide.B, cmLine, lineMapper.getLineB() + 1);
   }
 
   private int render(Region region, int cmLine, boolean useIntralineBg) {
@@ -141,11 +143,13 @@ class UnifiedChunkManager extends ChunkManager {
       addDiffChunk(DisplaySide.A, endA, endB, aLen, cmLine, bLen > 0);
       for (int j = 0; j < aLen; j++) {
         host.setLineNumber(DisplaySide.A, cmLine + j, startA + j + 1);
+        host.setLineNumberEmpty(DisplaySide.B, cmLine + j);
       }
     }
     if (bLen > 0) {
       addDiffChunk(DisplaySide.B, endB, endA, bLen, cmLine + aLen, aLen > 0);
       for (int j = 0; j < bLen; j++) {
+        host.setLineNumberEmpty(DisplaySide.A, cmLine + aLen + j);
         host.setLineNumber(DisplaySide.B, cmLine + aLen + j, startB + j + 1);
       }
     }

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

@@ -36,6 +36,7 @@ class UnifiedTable extends DiffTable {
     String diffInsert();
     String diffDelete();
     String unifiedLineNumber();
+    String unifiedLineNumberEmpty();
     String lineNumbersLeft();
     String lineNumbersRight();
   }

gerrit-gwtui/src/main/java/com/google/gerrit/client/diff/UnifiedTable.ui.xml

@@ -24,7 +24,7 @@ limitations under the License.
     @external .CodeMirror-dialog-bottom;
     @external .CodeMirror-cursor;
 
-    @external .dark, .unifiedLineNumber, .noIntraline;
+    @external .dark, .unifiedLineNumber, .noIntraline, .showLineNumbers;
 
     .difftable .patchSetNav,
     .difftable .CodeMirror {
@@ -94,21 +94,33 @@ limitations under the License.
       bottom: auto;
       left: auto;
     }
-
+    .showLineNumbers .lineNumbersLeft, .showLineNumbers .lineNumbersRight {
-    .lineNumbersLeft, .lineNumbersRight {
       min-width: 20px;
       width: 3em; /* TODO: This needs to be set based on number of lines */
     }
-    .lineNumbersLeft {
+    .showLineNumbers .lineNumbersLeft {
       border-right: 1px solid #ddd;
     }
     .unifiedLineNumber {
+      display: none;
+    }
+    .showLineNumbers .unifiedLineNumber {
+      display: block;
       cursor: pointer;
       padding: 0 3px 0 5px;
       min-width: 20px;
       text-align: right;
       color: #999;
     }
+    .unifiedLineNumberEmpty {
+      display: none;
+    }
+    .showLineNumbers .unifiedLineNumberEmpty {
+      display: block;
+      margin-left: 28px;
+      border-left: 2px solid #d64040;
+      padding-bottom: 1px;
+    }
   </ui:style>
   <g:HTMLPanel styleName='{style.difftable}'>
     <table class='{style.table}'>