Convert "preview" image transforms to new pathway

Summary: Ref T7707. Move the 220px (file uploads) and 100px (Pholio thumbgrid) previews over to the new stuff.

Test Plan: Uploaded a bunch of images to remarkup and Pholio; they generated reasonable results in the web UI.

Reviewers: btrahan

Reviewed By: btrahan

Subscribers: epriestley

Maniphest Tasks: T7707

Differential Revision: https://secure.phabricator.com/D12814

src/applications/files/PhabricatorImageTransformer.php

@@ -51,20 +51,6 @@ final class PhabricatorImageTransformer {
       ));
   }
 
-  public function executePreviewTransform(
-    PhabricatorFile $file,
-    $size) {
-
-    $image = $this->generatePreview($file, $size);
-
-    return PhabricatorFile::newFromFileData(
-      $image,
-      array(
-        'name' => 'preview-'.$file->getName(),
-        'canCDN' => true,
-      ));
-  }
-
   public function executeConpherenceTransform(
     PhabricatorFile $file,
     $top,
@@ -188,37 +174,6 @@ final class PhabricatorImageTransformer {
 
   }
 
-  public static function getPreviewDimensions(PhabricatorFile $file, $size) {
-    $metadata = $file->getMetadata();
-    $x = idx($metadata, PhabricatorFile::METADATA_IMAGE_WIDTH);
-    $y = idx($metadata, PhabricatorFile::METADATA_IMAGE_HEIGHT);
-
-    if (!$x || !$y) {
-      $data = $file->loadFileData();
-      $src = imagecreatefromstring($data);
-
-      $x = imagesx($src);
-      $y = imagesy($src);
-    }
-
-    $scale = min($size / $x, $size / $y, 1);
-
-    $dx = max($size / 4, $scale * $x);
-    $dy = max($size / 4, $scale * $y);
-
-    $sdx = $scale * $x;
-    $sdy = $scale * $y;
-
-    return array(
-      'x' => $x,
-      'y' => $y,
-      'dx' => $dx,
-      'dy' => $dy,
-      'sdx' => $sdx,
-      'sdy' => $sdy,
-    );
-  }
-
   public static function getScaleForCrop(
     PhabricatorFile $file,
     $des_width,
@@ -241,31 +196,6 @@ final class PhabricatorImageTransformer {
     return $scale;
   }
 
-  private function generatePreview(PhabricatorFile $file, $size) {
-    $data = $file->loadFileData();
-    $src = imagecreatefromstring($data);
-
-    $dimensions = self::getPreviewDimensions($file, $size);
-    $x = $dimensions['x'];
-    $y = $dimensions['y'];
-    $dx = $dimensions['dx'];
-    $dy = $dimensions['dy'];
-    $sdx = $dimensions['sdx'];
-    $sdy = $dimensions['sdy'];
-
-    $dst = $this->getBlankDestinationFile($dx, $dy);
-
-    imagecopyresampled(
-      $dst,
-      $src,
-      ($dx - $sdx) / 2, ($dy - $sdy) / 2,
-      0, 0,
-      $sdx, $sdy,
-      $x, $y);
-
-    return self::saveImageDataInAnyFormat($dst, $file->getMimeType());
-  }
-
   private function applyMemeToFile(
     PhabricatorFile $file,
     $upper_text,

src/applications/files/controller/PhabricatorFileTransformController.php

@@ -85,12 +85,6 @@ final class PhabricatorFileTransformController
         case 'thumb-280x210':
           $xformed_file = $this->executeThumbTransform($file, 280, 210);
           break;
-        case 'preview-100':
-          $xformed_file = $this->executePreviewTransform($file, 100);
-          break;
-        case 'preview-220':
-          $xformed_file = $this->executePreviewTransform($file, 220);
-          break;
         default:
           return new Aphront400Response();
       }
@@ -132,9 +126,6 @@ final class PhabricatorFileTransformController
       case 'thumb-280x210':
         $suffix = '280x210';
         break;
-      case 'preview-100':
-        $suffix = '.p100';
-        break;
       default:
         throw new Exception('Unsupported transformation type!');
     }
@@ -163,11 +154,6 @@ final class PhabricatorFileTransformController
     return $file->getRedirectResponse();
   }
 
-  private function executePreviewTransform(PhabricatorFile $file, $size) {
-    $xformer = new PhabricatorImageTransformer();
-    return $xformer->executePreviewTransform($file, $size);
-  }
-
   private function executeThumbTransform(PhabricatorFile $file, $x, $y) {
     $xformer = new PhabricatorImageTransformer();
     return $xformer->executeThumbTransform($file, $x, $y);

src/applications/files/markup/PhabricatorEmbedFileRemarkupRule.php

@@ -107,11 +107,17 @@ final class PhabricatorEmbedFileRemarkupRule
           break;
         case 'thumb':
         default:
-          $attrs['src'] = $file->getPreview220URI();
-          $dimensions =
-            PhabricatorImageTransformer::getPreviewDimensions($file, 220);
-          $attrs['width'] = $dimensions['dx'];
-          $attrs['height'] = $dimensions['dy'];
+          $preview_key = PhabricatorFileThumbnailTransform::TRANSFORM_PREVIEW;
+          $xform = PhabricatorFileTransform::getTransformByKey($preview_key);
+          $attrs['src'] = $file->getURIForTransform($xform);
+
+          $dimensions = $xform->getTransformedDimensions($file);
+          if ($dimensions) {
+            list($x, $y) = $dimensions;
+            $attrs['width'] = $x;
+            $attrs['height'] = $y;
+          }
+
           $image_class = 'phabricator-remarkup-embed-image';
           break;
       }

src/applications/files/storage/PhabricatorFile.php

@@ -788,14 +788,6 @@ final class PhabricatorFile extends PhabricatorFileDAO
     return $this->getTransformedURI('thumb-profile');
   }
 
-  public function getPreview100URI() {
-    return $this->getTransformedURI('preview-100');
-  }
-
-  public function getPreview220URI() {
-    return $this->getTransformedURI('preview-220');
-  }
-
   public function getThumb280x210URI() {
     return $this->getTransformedURI('thumb-280x210');
   }

src/applications/files/transform/PhabricatorFileImageTransform.php

@@ -8,6 +8,16 @@ abstract class PhabricatorFileImageTransform extends PhabricatorFileTransform {
   private $imageX;
   private $imageY;
 
+  /**
+   * Get an estimate of the transformed dimensions of a file.
+   *
+   * @param PhabricatorFile File to transform.
+   * @return list<int, int>|null Width and height, if available.
+   */
+  public function getTransformedDimensions(PhabricatorFile $file) {
+    return null;
+  }
+
   public function canApplyTransform(PhabricatorFile $file) {
     if (!$file->isViewableImage()) {
       return false;

src/applications/files/transform/PhabricatorFileThumbnailTransform.php

@@ -65,6 +65,59 @@ final class PhabricatorFileThumbnailTransform
     $dst_x = $this->dstX;
     $dst_y = $this->dstY;
 
+    $dimensions = $this->computeDimensions(
+      $src_x,
+      $src_y,
+      $dst_x,
+      $dst_y);
+
+    $copy_x = $dimensions['copy_x'];
+    $copy_y = $dimensions['copy_y'];
+    $use_x = $dimensions['use_x'];
+    $use_y = $dimensions['use_y'];
+    $dst_x = $dimensions['dst_x'];
+    $dst_y = $dimensions['dst_y'];
+
+    return $this->applyCropAndScale(
+      $dst_x,
+      $dst_y,
+      ($src_x - $copy_x) / 2,
+      ($src_y - $copy_y) / 2,
+      $copy_x,
+      $copy_y,
+      $use_x,
+      $use_y);
+  }
+
+
+  public function getTransformedDimensions(PhabricatorFile $file) {
+    $dst_x = $this->dstX;
+    $dst_y = $this->dstY;
+
+    // If this is transform has fixed dimensions, we can trivially predict
+    // the dimensions of the transformed file.
+    if ($dst_y !== null) {
+      return array($dst_x, $dst_y);
+    }
+
+    $src_x = $file->getImageWidth();
+    $src_y = $file->getImageHeight();
+
+    if (!$src_x || !$src_y) {
+      return null;
+    }
+
+    $dimensions = $this->computeDimensions(
+      $src_x,
+      $src_y,
+      $dst_x,
+      $dst_y);
+
+    return array($dimensions['dst_x'], $dimensions['dst_y']);
+  }
+
+
+  private function computeDimensions($src_x, $src_y, $dst_x, $dst_y) {
     if ($dst_y === null) {
       // If we only have one dimension, it represents a maximum dimension.
       // The other dimension of the transform is scaled appropriately, except
@@ -115,17 +168,17 @@ final class PhabricatorFileThumbnailTransform
       $use_y = $dst_y;
     }
 
-    return $this->applyCropAndScale(
-      $dst_x,
-      $dst_y,
-      ($src_x - $copy_x) / 2,
-      ($src_y - $copy_y) / 2,
-      $copy_x,
-      $copy_y,
-      $use_x,
-      $use_y);
+    return array(
+      'copy_x' => $copy_x,
+      'copy_y' => $copy_y,
+      'use_x' => $use_x,
+      'use_y' => $use_y,
+      'dst_x' => $dst_x,
+      'dst_y' => $dst_y,
+    );
   }
 
+
   public function getDefaultTransform(PhabricatorFile $file) {
     $x = (int)$this->dstX;
     $y = (int)$this->dstY;

src/applications/files/transform/PhabricatorFileTransform.php

@@ -45,4 +45,18 @@ abstract class PhabricatorFileTransform extends Phobject {
     return $map;
   }
 
+  public static function getTransformByKey($key) {
+    $all = self::getAllTransforms();
+
+    $xform = idx($all, $key);
+    if (!$xform) {
+      throw new Exception(
+        pht(
+          'No file transform with key "%s" exists.',
+          $key));
+    }
+
+    return $xform;
+  }
+
 }

src/applications/pholio/view/PholioMockThumbGridView.php

@@ -114,28 +114,34 @@ final class PholioMockThumbGridView extends AphrontView {
   private function renderThumbnail(PholioImage $image) {
     $thumbfile = $image->getFile();
 
+    $preview_key = PhabricatorFileThumbnailTransform::TRANSFORM_THUMBGRID;
+    $xform = PhabricatorFileTransform::getTransformByKey($preview_key);
+
+    $attributes = array(
+      'class' => 'pholio-mock-thumb-grid-image',
+      'src' => $thumbfile->getURIForTransform($xform),
+    );
+
     if ($image->getFile()->isViewableImage()) {
-      $dimensions = PhabricatorImageTransformer::getPreviewDimensions(
-        $thumbfile,
-        100);
+      $dimensions = $xform->getTransformedDimensions($thumbfile);
+      if ($dimensions) {
+        list($x, $y) = $dimensions;
+        $attributes += array(
+          'width' => $x,
+          'height' => $y,
+          'style' => 'top: '.floor((100 - $y) / 2).'px',
+        );
+      }
     } else {
       // If this is a PDF or a text file or something, we'll end up using a
       // generic thumbnail which is always sized correctly.
-      $dimensions = array(
-        'sdx' => 100,
-        'sdy' => 100,
+      $attributes += array(
+        'width' => 100,
+        'height' => 100,
       );
     }
 
-    $tag = phutil_tag(
-      'img',
-      array(
-        'width' => $dimensions['sdx'],
-        'height' => $dimensions['sdy'],
-        'src' => $thumbfile->getPreview100URI(),
-        'class' => 'pholio-mock-thumb-grid-image',
-        'style' => 'top: '.floor((100 - $dimensions['sdy'] ) / 2).'px',
-    ));
+    $tag = phutil_tag('img', $attributes);
 
     $classes = array('pholio-mock-thumb-grid-item');
     if ($image->getIsObsolete()) {