Render image diffs as abstract blocks diffs via DocumentEngine

Summary:
Depends on D20830. Ref T13425. Have the image engine elect into block rendering, then emit blocks.

This is rough (the blocks aren't actually diffed yet) but image diffs were already pretty rough so this is approximately a net improvement.

Test Plan: Viewed image diffs, saw nothing worse than before.

Maniphest Tasks: T13425

Differential Revision: https://secure.phabricator.com/D20831

resources/celerity/map.php

@@ -11,7 +11,7 @@ return array(
     'conpherence.pkg.js' => '020aebcf',
     'core.pkg.css' => 'c69171e6',
     'core.pkg.js' => '6e5c894f',
-    'differential.pkg.css' => '8d8360fb',
+    'differential.pkg.css' => 'eef74643',
     'differential.pkg.js' => '0b037a4f',
     'diffusion.pkg.css' => '42c75c37',
     'diffusion.pkg.js' => 'a98c0bf7',
@@ -61,7 +61,7 @@ return array(
     'rsrc/css/application/dashboard/dashboard.css' => '5a205b9d',
     'rsrc/css/application/diff/inline-comment-summary.css' => '81eb368d',
     'rsrc/css/application/differential/add-comment.css' => '7e5900d9',
-    'rsrc/css/application/differential/changeset-view.css' => 'bde53589',
+    'rsrc/css/application/differential/changeset-view.css' => '215129ef',
     'rsrc/css/application/differential/core.css' => '7300a73e',
     'rsrc/css/application/differential/phui-inline-comment.css' => '48acce5b',
     'rsrc/css/application/differential/revision-comment.css' => '7dbc8d1d',
@@ -554,7 +554,7 @@ return array(
     'conpherence-thread-manager' => 'aec8e38c',
     'conpherence-transaction-css' => '3a3f5e7e',
     'd3' => '9d068042',
-    'differential-changeset-view-css' => 'bde53589',
+    'differential-changeset-view-css' => '215129ef',
     'differential-core-view-css' => '7300a73e',
     'differential-revision-add-comment-css' => '7e5900d9',
     'differential-revision-comment-css' => '7dbc8d1d',
@@ -1069,6 +1069,9 @@ return array(
       'javelin-behavior',
       'javelin-request',
     ),
+    '215129ef' => array(
+      'phui-inline-comment-view-css',
+    ),
     '225bbb98' => array(
       'javelin-install',
       'javelin-reactor',
@@ -1960,9 +1963,6 @@ return array(
       'phabricator-drag-and-drop-file-upload',
       'javelin-workboard-board',
     ),
-    'bde53589' => array(
-      'phui-inline-comment-view-css',
-    ),
     'c03f2fb4' => array(
       'javelin-install',
     ),

src/__phutil_library_map__.php

@@ -3138,6 +3138,8 @@ phutil_register_library_map(array(
     'PhabricatorDividerProfileMenuItem' => 'applications/search/menuitem/PhabricatorDividerProfileMenuItem.php',
     'PhabricatorDivinerApplication' => 'applications/diviner/application/PhabricatorDivinerApplication.php',
     'PhabricatorDocumentEngine' => 'applications/files/document/PhabricatorDocumentEngine.php',
+    'PhabricatorDocumentEngineBlock' => 'applications/files/diff/PhabricatorDocumentEngineBlock.php',
+    'PhabricatorDocumentEngineBlocks' => 'applications/files/diff/PhabricatorDocumentEngineBlocks.php',
     'PhabricatorDocumentRef' => 'applications/files/document/PhabricatorDocumentRef.php',
     'PhabricatorDocumentRenderingEngine' => 'applications/files/document/render/PhabricatorDocumentRenderingEngine.php',
     'PhabricatorDoorkeeperApplication' => 'applications/doorkeeper/application/PhabricatorDoorkeeperApplication.php',
@@ -9471,6 +9473,8 @@ phutil_register_library_map(array(
     'PhabricatorDividerProfileMenuItem' => 'PhabricatorProfileMenuItem',
     'PhabricatorDivinerApplication' => 'PhabricatorApplication',
     'PhabricatorDocumentEngine' => 'Phobject',
+    'PhabricatorDocumentEngineBlock' => 'Phobject',
+    'PhabricatorDocumentEngineBlocks' => 'Phobject',
     'PhabricatorDocumentRef' => 'Phobject',
     'PhabricatorDocumentRenderingEngine' => 'Phobject',
     'PhabricatorDoorkeeperApplication' => 'PhabricatorApplication',

src/applications/differential/parser/DifferentialChangesetParser.php

@@ -1013,17 +1013,8 @@ final class DifferentialChangesetParser extends Phobject {
       ->setOldComments($old_comments)
       ->setNewComments($new_comments);
 
-    $engine_view = $this->newDocumentEngineChangesetView();
-    if ($engine_view !== null) {
-      return $engine_view;
-    }
-
-    switch ($this->changeset->getFileType()) {
-      case DifferentialChangeType::FILE_IMAGE:
-        $old = null;
-        $new = null;
-        // TODO: Improve the architectural issue as discussed in D955
-        // https://secure.phabricator.com/D955
+    $engine_blocks = $this->newDocumentEngineChangesetView();
+    if ($engine_blocks !== null) {
       $reference = $this->getRenderingReference();
       $parts = explode('/', $reference);
       if (count($parts) == 2) {
@@ -1032,65 +1023,26 @@ final class DifferentialChangesetParser extends Phobject {
         $id = $parts[0];
         $vs = 0;
       }
-        $id = (int)$id;
-        $vs = (int)$vs;
 
+      // If we don't have an explicit "vs" changeset, it's the left side of
+      // the "id" changeset.
       if (!$vs) {
-          $metadata = $this->changeset->getMetadata();
-          $data = idx($metadata, 'attachment-data');
-
-          $old_phid = idx($metadata, 'old:binary-phid');
-          $new_phid = idx($metadata, 'new:binary-phid');
-        } else {
-          $vs_changeset = id(new DifferentialChangeset())->load($vs);
-          $old_phid = null;
-          $new_phid = null;
-
-          // TODO: This is spooky, see D6851
-          if ($vs_changeset) {
-            $vs_metadata = $vs_changeset->getMetadata();
-            $old_phid = idx($vs_metadata, 'new:binary-phid');
+        $vs = $id;
       }
 
-          $changeset = id(new DifferentialChangeset())->load($id);
-          if ($changeset) {
-            $metadata = $changeset->getMetadata();
-            $new_phid = idx($metadata, 'new:binary-phid');
-          }
+      return $renderer->renderDocumentEngineBlocks(
+        $engine_blocks,
+        (string)$id,
+        (string)$vs);
     }
 
-        if ($old_phid || $new_phid) {
-          // grab the files, (micro) optimization for 1 query not 2
-          $file_phids = array();
-          if ($old_phid) {
-            $file_phids[] = $old_phid;
-          }
-          if ($new_phid) {
-            $file_phids[] = $new_phid;
-          }
-
-          $files = id(new PhabricatorFileQuery())
-            ->setViewer($this->getUser())
-            ->withPHIDs($file_phids)
-            ->execute();
-          foreach ($files as $file) {
-            if (empty($file)) {
-              continue;
-            }
-            if ($file->getPHID() == $old_phid) {
-              $old = $file;
-            } else if ($file->getPHID() == $new_phid) {
-              $new = $file;
-            }
-          }
-        }
-
-        $renderer->attachOldFile($old);
-        $renderer->attachNewFile($new);
-
-        return $renderer->renderFileChange($old, $new, $id, $vs);
+    // If we've made it here with a type of file we don't know how to render,
+    // bail out with a default empty rendering. Normally, we'd expect a
+    // document engine to catch these changes before we make it this far.
+    switch ($this->changeset->getFileType()) {
       case DifferentialChangeType::FILE_DIRECTORY:
       case DifferentialChangeType::FILE_BINARY:
+      case DifferentialChangeType::FILE_IMAGE:
         $output = $renderer->renderChangesetTable(null);
         return $output;
     }
@@ -1699,21 +1651,39 @@ final class DifferentialChangesetParser extends Phobject {
       return null;
     }
 
+    $old_file = null;
+    $new_file = null;
+
+    switch ($changeset->getFileType()) {
+      case DifferentialChangeType::FILE_IMAGE:
+      case DifferentialChangeType::FILE_BINARY:
+        list($old_file, $new_file) = $this->loadFileObjectsForChangeset();
+        break;
+    }
+
+    $old_ref = id(new PhabricatorDocumentRef())
+      ->setName($changeset->getOldFile());
+    if ($old_file) {
+      $old_ref->setFile($old_file);
+    } else {
       $old_data = $this->old;
       $old_data = ipull($old_data, 'text');
       $old_data = implode('', $old_data);
 
+      $old_ref->setData($old_data);
+    }
+
+    $new_ref = id(new PhabricatorDocumentRef())
+      ->setName($changeset->getFilename());
+    if ($new_file) {
+      $new_ref->setFile($new_file);
+    } else {
       $new_data = $this->new;
       $new_data = ipull($new_data, 'text');
       $new_data = implode('', $new_data);
 
-    $old_ref = id(new PhabricatorDocumentRef())
-      ->setName($changeset->getOldFile())
-      ->setData($old_data);
-
-    $new_ref = id(new PhabricatorDocumentRef())
-      ->setName($changeset->getFilename())
-      ->setData($new_data);
+      $new_ref->setData($old_data);
+    }
 
     $old_engines = PhabricatorDocumentEngine::getEnginesForRef(
       $viewer,
@@ -1743,4 +1713,74 @@ final class DifferentialChangesetParser extends Phobject {
     return null;
   }
 
+  private function loadFileObjectsForChangeset() {
+    $changeset = $this->changeset;
+    $viewer = $this->getViewer();
+
+    $old_file = null;
+    $new_file = null;
+
+    // TODO: Improve the architectural issue as discussed in D955
+    // https://secure.phabricator.com/D955
+    $reference = $this->getRenderingReference();
+    $parts = explode('/', $reference);
+    if (count($parts) == 2) {
+      list($id, $vs) = $parts;
+    } else {
+      $id = $parts[0];
+      $vs = 0;
+    }
+    $id = (int)$id;
+    $vs = (int)$vs;
+
+    if (!$vs) {
+      $metadata = $this->changeset->getMetadata();
+      $data = idx($metadata, 'attachment-data');
+
+      $old_phid = idx($metadata, 'old:binary-phid');
+      $new_phid = idx($metadata, 'new:binary-phid');
+    } else {
+      $vs_changeset = id(new DifferentialChangeset())->load($vs);
+      $old_phid = null;
+      $new_phid = null;
+
+      // TODO: This is spooky, see D6851
+      if ($vs_changeset) {
+        $vs_metadata = $vs_changeset->getMetadata();
+        $old_phid = idx($vs_metadata, 'new:binary-phid');
+      }
+
+      $changeset = id(new DifferentialChangeset())->load($id);
+      if ($changeset) {
+        $metadata = $changeset->getMetadata();
+        $new_phid = idx($metadata, 'new:binary-phid');
+      }
+    }
+
+    if ($old_phid || $new_phid) {
+      $file_phids = array();
+      if ($old_phid) {
+        $file_phids[] = $old_phid;
+      }
+      if ($new_phid) {
+        $file_phids[] = $new_phid;
+      }
+
+      $files = id(new PhabricatorFileQuery())
+        ->setViewer($viewer)
+        ->withPHIDs($file_phids)
+        ->execute();
+
+      foreach ($files as $file) {
+        if ($file->getPHID() == $old_phid) {
+          $old_file = $file;
+        } else if ($file->getPHID() == $new_phid) {
+          $new_file = $file;
+        }
+      }
+    }
+
+    return array($old_file, $new_file);
+  }
+
 }

src/applications/differential/render/DifferentialChangesetHTMLRenderer.php

@@ -608,17 +608,4 @@ abstract class DifferentialChangesetHTMLRenderer
     return array($left_prefix, $right_prefix);
   }
 
-  protected function renderImageStage(PhabricatorFile $file) {
-    return phutil_tag(
-      'div',
-      array(
-        'class' => 'differential-image-stage',
-      ),
-      phutil_tag(
-        'img',
-        array(
-          'src' => $file->getBestURI(),
-        )));
-  }
-
 }

src/applications/differential/render/DifferentialChangesetOneUpMailRenderer.php

@@ -31,14 +31,6 @@ final class DifferentialChangesetOneUpMailRenderer
     return null;
   }
 
-  public function renderFileChange(
-    $old_file = null,
-    $new_file = null,
-    $id = 0,
-    $vs = 0) {
-    return null;
-  }
-
   public function renderTextChange(
     $range_start,
     $range_len,

src/applications/differential/render/DifferentialChangesetOneUpRenderer.php

@@ -228,34 +228,21 @@ final class DifferentialChangesetOneUpRenderer
     return null;
   }
 
-  public function renderFileChange(
-    $old_file = null,
-    $new_file = null,
-    $id = 0,
-    $vs = 0) {
+  public function renderDocumentEngineBlocks(
+    PhabricatorDocumentEngineBlocks $block_list,
+    $old_changeset_key,
+    $new_changeset_key) {
 
     // TODO: This should eventually merge into the normal primitives pathway,
     // but fake it for now and just share as much code as possible.
 
     $primitives = array();
-    if ($old_file) {
+    foreach ($block_list->newOneUpLayout() as $block) {
       $primitives[] = array(
         'type' => 'old-file',
-        'htype' => ($new_file ? 'new-file' : null),
-        'file' => $old_file,
+        'htype' => '',
         'line' => 1,
-        'render' => $this->renderImageStage($old_file),
-      );
-    }
-
-    if ($new_file) {
-      $primitives[] = array(
-        'type' => 'new-file',
-        'htype' => ($old_file ? 'old-file' : null),
-        'file' => $new_file,
-        'line' => 1,
-        'oline' => ($old_file ? 1 : null),
-        'render' => $this->renderImageStage($new_file),
+        'render' => $block->newContentView(),
       );
     }
 

src/applications/differential/render/DifferentialChangesetRenderer.php

@@ -378,11 +378,13 @@ abstract class DifferentialChangesetRenderer extends Phobject {
     $range_start,
     $range_len,
     $rows);
-  abstract public function renderFileChange(
-    $old = null,
-    $new = null,
-    $id = 0,
-    $vs = 0);
+
+  public function renderDocumentEngineBlocks(
+    PhabricatorDocumentEngineBlocks $blocks,
+    $old_changeset_key,
+    $new_changeset_key) {
+    return null;
+  }
 
   abstract protected function renderChangeTypeHeader($force);
   abstract protected function renderUndershieldHeader();

src/applications/differential/render/DifferentialChangesetTestRenderer.php

@@ -134,14 +134,4 @@ abstract class DifferentialChangesetTestRenderer
     return phutil_safe_html($out);
   }
 
-
-  public function renderFileChange(
-    $old_file = null,
-    $new_file = null,
-    $id = 0,
-    $vs = 0) {
-
-    throw new PhutilMethodNotImplementedException();
-  }
-
 }

src/applications/differential/render/DifferentialChangesetTwoUpRenderer.php

@@ -364,26 +364,28 @@ final class DifferentialChangesetTwoUpRenderer
     return $this->wrapChangeInTable(phutil_implode_html('', $html));
   }
 
-  public function renderFileChange(
-    $old_file = null,
-    $new_file = null,
-    $id = 0,
-    $vs = 0) {
+  public function renderDocumentEngineBlocks(
+    PhabricatorDocumentEngineBlocks $block_list,
+    $old_changeset_key,
+    $new_changeset_key) {
 
-    $old = null;
-    if ($old_file) {
-      $old = $this->renderImageStage($old_file);
+    $old_view = null;
+    $new_view = null;
+
+    foreach ($block_list->newTwoUpLayout() as $row) {
+      list($old, $new) = $row;
+
+      if ($old) {
+        $old_view = $old->newContentView();
+      } else {
+        $old_view = null;
       }
 
-    $new = null;
-    if ($new_file) {
-      $new = $this->renderImageStage($new_file);
+      if ($new) {
+        $new_view = $new->newContentView();
+      } else {
+        $new_view = null;
       }
-
-    // If we don't have an explicit "vs" changeset, it's the left side of the
-    // "id" changeset.
-    if (!$vs) {
-      $vs = $id;
     }
 
     $html_old = array();
@@ -405,31 +407,52 @@ final class DifferentialChangesetTwoUpRenderer
       }
     }
 
-    if (!$old) {
-      $th_old = phutil_tag('th', array());
+    if ($old_view === null) {
+      $old_id = null;
+      $old_label = null;
     } else {
-      $th_old = phutil_tag('th', array('id' => "C{$vs}OL1"), 1);
+      $old_id = "C{$old_changeset_key}OL1";
+      $old_label = '1';
     }
 
-    if (!$new) {
-      $th_new = phutil_tag('th', array());
+    $old_cell = phutil_tag(
+      'td',
+      array(
+        'id' => $old_id,
+        'class' => 'n',
+      ),
+      $old_label);
+
+    if ($new_view === null) {
+      $new_id = null;
+      $new_label = null;
     } else {
-      $th_new = phutil_tag('th', array('id' => "C{$id}NL1"), 1);
+      $new_id = "C{$new_changeset_key}NL1";
+      $new_label = '1';
     }
 
+    $new_cell = phutil_tag(
+      'td',
+      array(
+        'id' => $new_id,
+        'class' => 'n',
+      ),
+      $new_label);
+
     $output = hsprintf(
       '<tr class="differential-image-diff">'.
         '%s'.
-        '<td class="differential-old-image">%s</td>'.
+        '<td class="differential-old-image diff-image-cell">%s</td>'.
         '%s'.
-        '<td class="differential-new-image" colspan="3">%s</td>'.
+        '<td class="differential-new-image diff-image-cell" '.
+          'colspan="3">%s</td>'.
       '</tr>'.
       '%s'.
       '%s',
-      $th_old,
-      $old,
-      $th_new,
-      $new,
+      $old_cell,
+      $old_view,
+      $new_cell,
+      $new_view,
       phutil_implode_html('', $html_old),
       phutil_implode_html('', $html_new));
 

src/applications/files/diff/PhabricatorDocumentEngineBlock.php

@@ -0,0 +1,21 @@
+<?php
+
+final class PhabricatorDocumentEngineBlock
+  extends Phobject {
+
+  private $content;
+
+  public function setContent($content) {
+    $this->content = $content;
+    return $this;
+  }
+
+  public function getContent() {
+    return $this->content;
+  }
+
+  public function newContentView() {
+    return $this->getContent();
+  }
+
+}

src/applications/files/diff/PhabricatorDocumentEngineBlocks.php

@@ -0,0 +1,83 @@
+<?php
+
+final class PhabricatorDocumentEngineBlocks
+  extends Phobject {
+
+  private $lists = array();
+
+  public function addBlockList(PhabricatorDocumentRef $ref, array $blocks) {
+    assert_instances_of($blocks, 'PhabricatorDocumentEngineBlock');
+
+    $this->lists[] = array(
+      'ref' => $ref,
+      'blocks' => array_values($blocks),
+    );
+
+    return $this;
+  }
+
+  public function newTwoUpLayout() {
+    $rows = array();
+    $lists = $this->lists;
+
+    $idx = 0;
+    while (true) {
+      $found_any = false;
+
+      $row = array();
+      foreach ($lists as $list) {
+        $blocks = $list['blocks'];
+        $cell = idx($blocks, $idx);
+
+        if ($cell !== null) {
+          $found_any = true;
+        }
+
+        $row[] = $cell;
+      }
+
+      if (!$found_any) {
+        break;
+      }
+
+      $rows[] = $row;
+      $idx++;
+    }
+
+    return $rows;
+  }
+
+  public function newOneUpLayout() {
+    $rows = array();
+    $lists = $this->lists;
+
+    $idx = 0;
+    while (true) {
+      $found_any = false;
+
+      $row = array();
+      foreach ($lists as $list) {
+        $blocks = $list['blocks'];
+        $cell = idx($blocks, $idx);
+
+        if ($cell !== null) {
+          $found_any = true;
+        }
+
+        if ($cell) {
+          $rows[] = $cell;
+        }
+      }
+
+      if (!$found_any) {
+        break;
+      }
+
+      $idx++;
+    }
+
+    return $rows;
+  }
+
+
+}

src/applications/files/document/PhabricatorImageDocumentEngine.php

@@ -17,6 +17,50 @@ final class PhabricatorImageDocumentEngine
     return (1024 * 1024 * 64);
   }
 
+  public function canDiffDocuments(
+    PhabricatorDocumentRef $uref,
+    PhabricatorDocumentRef $vref) {
+
+    // For now, we can only render a rich image diff if both documents have
+    // their data stored in Files already.
+
+    return ($uref->getFile() && $vref->getFile());
+  }
+
+  public function newDiffView(
+    PhabricatorDocumentRef $uref,
+    PhabricatorDocumentRef $vref) {
+
+    $u_blocks = $this->newDiffBlocks($uref);
+    $v_blocks = $this->newDiffBlocks($vref);
+
+    return id(new PhabricatorDocumentEngineBlocks())
+      ->addBlockList($uref, $u_blocks)
+      ->addBlockList($vref, $v_blocks);
+  }
+
+  private function newDiffBlocks(PhabricatorDocumentRef $ref) {
+    $blocks = array();
+
+    $file = $ref->getFile();
+
+    $image_view = phutil_tag(
+      'div',
+      array(
+        'class' => 'differential-image-stage',
+      ),
+      phutil_tag(
+        'img',
+        array(
+          'src' => $file->getBestURI(),
+        )));
+
+    $blocks[] = id(new PhabricatorDocumentEngineBlock())
+      ->setContent($image_view);
+
+    return $blocks;
+  }
+
   protected function canRenderDocumentType(PhabricatorDocumentRef $ref) {
     $file = $ref->getFile();
     if ($file) {

webroot/rsrc/css/application/differential/changeset-view.css

@@ -282,11 +282,11 @@ td.cov-I {
   font-weight: bold;
 }
 
-.differential-diff .differential-image-diff {
+.differential-diff .diff-image-cell {
   background-image: url(/rsrc/image/checker_light.png);
 }
 
-.differential-diff .differential-image-diff:hover {
+.device-desktop .differential-diff .diff-image-cell:hover {
   background-image: url(/rsrc/image/checker_dark.png);
 }