Use ApplicationSearch in Diffusion

Summary:
Ref T2625. Switches Diffusion to ApplicationSearch. Notes:

  - Rendering is a bit rough, I'll clean that up next.
  - Ordering is a bit arbitrary, also coming shortly.

Test Plan: Used `/diffusion/` to execute various searches.

Reviewers: btrahan

Reviewed By: btrahan

CC: aran

Maniphest Tasks: T2625

Differential Revision: https://secure.phabricator.com/D6917

src/applications/repository/query/PhabricatorRepositorySearchEngine.php

@@ -0,0 +1,66 @@
+<?php
+
+final class PhabricatorRepositorySearchEngine
+  extends PhabricatorApplicationSearchEngine {
+
+  public function buildSavedQueryFromRequest(AphrontRequest $request) {
+    $saved = new PhabricatorSavedQuery();
+
+    $saved->setParameter('callsigns', $request->getStrList('callsigns'));
+
+    return $saved;
+  }
+
+  public function buildQueryFromSavedQuery(PhabricatorSavedQuery $saved) {
+    $query = id(new PhabricatorRepositoryQuery())
+      ->needCommitCounts(true)
+      ->needMostRecentCommits(true);
+
+    $callsigns = $saved->getParameter('callsigns');
+    if ($callsigns) {
+      $query->withCallsigns($callsigns);
+    }
+
+    return $query;
+  }
+
+  public function buildSearchForm(
+    AphrontFormView $form,
+    PhabricatorSavedQuery $saved_query) {
+
+    $callsigns = $saved_query->getParameter('callsigns', array());
+
+    $form
+      ->appendChild(
+        id(new AphrontFormTextControl())
+          ->setName('callsigns')
+          ->setLabel(pht('Callsigns'))
+          ->setValue(implode(', ', $callsigns)));
+  }
+
+  protected function getURI($path) {
+    return '/diffusion/'.$path;
+  }
+
+  public function getBuiltinQueryNames() {
+    $names = array(
+      'all' => pht('All Repositories'),
+    );
+
+    return $names;
+  }
+
+  public function buildSavedQueryFromBuiltin($query_key) {
+
+    $query = $this->newSavedQuery();
+    $query->setQueryKey($query_key);
+
+    switch ($query_key) {
+      case 'all':
+        return $query;
+    }
+
+    return parent::buildSavedQueryFromBuiltin($query_key);
+  }
+
+}