Pholio - add concept of replacing images and primitive history view

Summary:
Now you can actually replace an image! Ref T3572. This ended up needing a wee bit of infrastructure to work...

 - add replace image transaction to pholio
 - add replacesImagePHID to PholioImage
 - tweaks to editor to properly update images with respect to replacement
   - add edges to track replacement
 - expose getNodes on graph query infrastructure to query the entire graph of who replaced who
 - move pholio image to new phid infrastructure

Still TODO - the history view should get chopped out a bit from the current view - no more inline comments / generally less functionality plus maybe a tweak or two to make this more sensical.

Test Plan: replaced images and played with history controller a little. works okay.

Reviewers: epriestley

Reviewed By: epriestley

CC: aran, Korvin

Maniphest Tasks: T3572

Differential Revision: https://secure.phabricator.com/D6560

src/applications/pholio/controller/PholioMockViewController.php

@@ -76,6 +76,8 @@ final class PholioMockViewController extends PholioController {
     require_celerity_resource('pholio-css');
     require_celerity_resource('pholio-inline-comments-css');
 
+    $image_status = $this->getImageStatus($mock, $this->imageID);
+
     $comment_form_id = celerity_generate_unique_node_id();
     $output = id(new PholioMockImagesView())
       ->setRequestURI($request->getRequestURI())
@@ -100,6 +102,7 @@ final class PholioMockViewController extends PholioController {
 
     $content = array(
       $crumbs,
+      $image_status,
       $header,
       $actions,
       $properties,
@@ -117,6 +120,43 @@ final class PholioMockViewController extends PholioController {
       ));
   }
 
+  private function getImageStatus(PholioMock $mock, $image_id) {
+    $status = null;
+    $images = $mock->getImages();
+    foreach ($images as $image) {
+      if ($image->getID() == $image_id) {
+        return $status;
+      }
+    }
+
+    $images = $mock->getAllImages();
+    $images = mpull($images, null, 'getID');
+    $image = idx($images, $image_id);
+
+    if ($image) {
+      $history = $mock->getImageUpdateSet($image_id);
+      $latest_image = last($history);
+      $href = $this->getApplicationURI(
+        'image/history/'.$latest_image->getID().'/');
+      $status = id(new AphrontErrorView())
+        ->setSeverity(AphrontErrorView::SEVERITY_NOTICE)
+        ->setTitle(pht('The requested image is obsolete.'))
+        ->appendChild(phutil_tag(
+          'p',
+          array(),
+          array(
+            pht('You are viewing this mock with the latest image set.'),
+            ' ',
+            phutil_tag(
+              'a',
+              array('href' => $href),
+              pht(
+                'Click here to see the history of the now obsolete image.')))));
+    }
+
+    return $status;
+  }
+
   private function buildActionView(PholioMock $mock) {
     $user = $this->getRequest()->getUser();