Add basic NUX support to SearchEngines

Summary:
This is just putting a hook in that pretty much works. Behavior:

  - If you visit `/maniphest/?nux=true`, it always shows NUX for testing.
  - Otherwise, it shows NUX if there are no objects in the application yet.

Test Plan: {F1031846}

Reviewers: chad

Reviewed By: chad

Differential Revision: https://secure.phabricator.com/D14828

src/applications/search/controller/PhabricatorApplicationSearchController.php

@@ -107,13 +107,21 @@ final class PhabricatorApplicationSearchController
         // URIs like "/query/?users=a,b".
         $pt_data = $request->getPassthroughRequestData();
 
+        $exempt = array(
+          'before' => true,
+          'after' => true,
+          'nux' => true,
+        );
+
         foreach ($pt_data as $pt_key => $pt_value) {
-          if ($pt_key != 'before' && $pt_key != 'after') {
+          if (isset($exempt[$pt_key])) {
+            continue;
+          }
+
           $found_query_data = true;
           break;
         }
       }
-      }
 
       if (!$found_query_data) {
         // Otherwise, there's no query data so just run the user's default
@@ -203,12 +211,15 @@ final class PhabricatorApplicationSearchController
 
     $body[] = $box;
 
+
     if ($run_query) {
       $box->setAnchor(
         id(new PhabricatorAnchorView())
           ->setAnchorName('R'));
 
       try {
+        $engine->setRequest($request);
+
         $query = $engine->buildQueryFromSavedQuery($saved_query);
 
         $pager = $engine->newPagerForSavedQuery($saved_query);
@@ -216,7 +227,16 @@ final class PhabricatorApplicationSearchController
 
         $objects = $engine->executeQuery($query, $pager);
 
-        $engine->setRequest($request);
+        $force_nux = $request->getBool('nux');
+        if (!$objects || $force_nux) {
+          $nux_view = $this->renderNewUserView($engine, $force_nux);
+        } else {
+          $nux_view = null;
+        }
+
+        if ($nux_view) {
+          $box->appendChild($nux_view);
+        } else {
           $list = $engine->renderResults($objects, $saved_query);
 
           if (!($list instanceof PhabricatorApplicationSearchResultView)) {
@@ -258,7 +278,7 @@ final class PhabricatorApplicationSearchController
               ->appendChild($pager);
             $body[] = $pager_box;
           }
-
+        }
       } catch (PhabricatorTypeaheadInvalidTokenException $ex) {
         $errors[] = pht(
           'This query specifies an invalid parameter. Review the '.
@@ -396,4 +416,47 @@ final class PhabricatorApplicationSearchController
     return $nav;
   }
 
+  private function renderNewUserView(
+    PhabricatorApplicationSearchEngine $engine,
+    $force_nux) {
+
+    // Don't render NUX if the user has clicked away from the default page.
+    if (strlen($this->getQueryKey())) {
+      return null;
+    }
+
+    // Don't put NUX in panels because it would be weird.
+    if ($engine->isPanelContext()) {
+      return null;
+    }
+
+    // Try to render the view itself first, since this should be very cheap
+    // (just returning some text).
+    $nux_view = $engine->renderNewUserView();
+
+    if (!$nux_view) {
+      return null;
+    }
+
+    $query = $engine->newQuery();
+    if (!$query) {
+      return null;
+    }
+
+    // Try to load any object at all. If we can, the application has seen some
+    // use so we just render the normal view.
+    if (!$force_nux) {
+      $object = $query
+        ->setViewer(PhabricatorUser::getOmnipotentUser())
+        ->setLimit(1)
+        ->execute();
+      if ($object) {
+        return null;
+      }
+    }
+
+    return $nux_view;
+  }
+
+
 }

src/applications/search/engine/PhabricatorApplicationSearchEngine.php

@@ -1354,4 +1354,28 @@ abstract class PhabricatorApplicationSearchEngine extends Phobject {
     return $attachments;
   }
 
+  final public function renderNewUserView() {
+    $head = $this->getNewUserHeader();
+    $body = $this->getNewUserBody();
+
+    if (!strlen($head) && !strlen($body)) {
+      return null;
+    }
+
+    $viewer = $this->requireViewer();
+
+    return id(new PHUIBoxView())
+      ->addMargin(PHUI::MARGIN_LARGE)
+      ->appendChild($head)
+      ->appendChild(new PHUIRemarkupView($viewer, $body));
+  }
+
+  protected function getNewUserHeader() {
+    return null;
+  }
+
+  protected function getNewUserBody() {
+    return null;
+  }
+
 }